AFR 205s + big cam = 128mph
11-21-2005, 02:16 PM
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Melting Slicks
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AFR 205s + big cam = 128mph
Well, I've been meaning to make one of my rather lengthy posts, but I've been really busy over the last few weeks. We've been playing around with the idea of swapping heads on Tommy's car to see if we could pick up some power.
The current LS6 casting were originally done by Jay @ Absolute Speed. Last year the heads dropped a seat, so the heads were taken over to Greg Good here in Houston. Greg replaced all the seats in the heads. Greg also commented that the heads were "soft" on the exhaust side, so he touched up the exhaust side.
The car was put together last year, to be ready for Thunder. The car broke the rear on the first pass at Thunder with the Exedy clutch. After that, we made four passes in the car in Houston, and destroyed the Exedy clutch. The Exedy was replaced by a Textralia clutch. We made some passes in bad weather with the Textralia clutch and the car ran some 10.90's. Finally a few weeks ago, the car made a few laps at Motosports Ranch with Lou Sr. giving demo rides. In almost a year, thats all the time the car had on it....
So, we decided to make some changes to the car. In talking with Tony M. @ AFR, we had been planning to run a 225 head. Since we were in a time crunch to get the car ready for San Antonio, we decided to just run a 205 head since Lou had run them with pretty good success in his car last year.
Anyhow, Tony provided us witha set of milled 205's and a "Mamo-fied" FAST intake. The plan was to do a A-B swap on the car with no changes other than heads and observe the delta. Let me just say that Tony does a fantastic job on the FAST intake. He fixes some of the current issues with the manifold, and when you look up the port you can certainly see he's been busy up in there. When you compare the differneces to an out of the box FAST 90 the differences are glaring. Tony also has a nice hand, as the cosmetic side of his hand finished stuff really looks nice. While being pretty isn't always important, its certainly nice to see someone take real pride in their work.
The car was taken to MTI where all the work was performed. A baseline dyno was done of the car. As I said above, it had really no time on the motor a few passes and a few dyno pulls, and about 12 miles at the road course. Anyhow, a baseline dyno indicated that something was not right. The car had previously dyno'd 503RWHP at MTI. It was now showing about 460. A fresh set of plugs were installed along with an o2 sensor. Power dropped to 450. A cranking compression test showed about 178-182 psi on all cylinders. A leakdown test was the performed.
#1 - 15%
#2 - 6%
#3 - 7%
#4 - 12%
#5 - 11%
#6 - 8%
#7 - 9%
#8 - 8%
Hmmmmm.... Well, the tune was checked on the car, along with anything else that was readily visible. Nothing really looked off, except the power.
So it was decided since we we were running out of time to swap heads to see if we had an issue with the heads "going away". The heads and intake were swapped, and the combination was re-dynoed. The car made 487.4RWHP and 416.1 RWTQ with the belts on, and 492.9/425.2 with the belts off. The 503 RWHP graph has a small rev limiter bump in it, so the actual peak may not be 503. It may be around 500 or so. Also, MTI was only reving the car to 6800-6900. It'll make power to 7300, so there may be a bit of power up top not shown on the graph.
Anyhow, The fine folks at MTI buttoned up everything, and Jason tightened up the tune just a bit, and we were off to the races. I haven't seen the car in over 9 months, and haven't raced it competitively for almost 2 yrs. It's probably been 10 months since I made a full pass in the car. So, I was anxious to see what it was going to do.
My first impression of the car is that drivability was improved 1000%. The cam in the car is a BIG max effort cam from Ed Curtis. With the LS6 castings you had some low speed surge in first and second. This was not as big on a SD tune as you could load the car into 3rd or 4th and putt around. Once it was under load, it was fine. I noticed that with the 205s on the car all low speed surge is gone. Tip in and drivability was also greatly improved. I drove the car around in the pits creeping around in first with zero drama. I could have easily driven the car in traffic without having to do a lot of dancing on the clutch, etc...
We only had a couple of qualifying passes in the car before eliminations, so I didn't have a lot of time to sort out launch rpm, etc...But I have found that the Aussie clutch is probably the absolute best clutch we've ever had in the car, bar none. It grabs harder than the McLeod dual disc, and it lasted unlike the Exedy that was in the car. There was so much bite with the clutch, that the car was spinning. This may also be due to the fact that we have a set of ET Streets that were a year old.
Anyhow, our next order of business is to play with clutch slip and get the 60's back into the mid 1.4's We were cutting 1.5's all day in the car. I was simply launching the car as we always have, as like I said, I hadn't had time to do any testing to see wha the car might like. I also didn't have any time to test any real changes before eliminations.
DA was +2350 - +2400 on the weather station Even in those rather poor conditions, the car was making good power.
rev limiter @ 6900
60 - 1.5301
330 - 4.5809
1/8 - 7.0952
mph - 97.28
1000 - 9.2673
1/4 - 11.0798
mph - 127.01
60 - 1.5759
330 - 4.5487
1/8 - 7.0281
mph - 96.69
1000 - 9.1672
1/4 - 10.9675
mph - 127.70
Rev limiter @ 7400
60 - 1.5687
330 - 4.5548
1/8 - 7.0271
mph - 98.04
1000 - 9.4505
1/4 - 11.9251
mph - 85.62
(missed 4th on that pass)
60 - 1.5052
330 - 4.5164
1/8 - 7.0003
mph - 98.04
1000 - 9.1539
1/4 - 10.9575
mph - 127.44
60 - 1.5253
330 - 4.4827
1/8 - 6.9476
mph - 98.86
1000 - 9.0896
1/4 - 10.8822
mph - 128.28
60 - 1.5278
330 - 4.4979
1/8 - 6.9628
mph - 98.99
1000 - 9.1016
1/4 - 10.8925
mph - 128.39
So, this brings up several good points. The car is going faster in worse air with less indicated peak HP than it had previously. There are no huge midrange gains shown on the graphs. What I'd like to illustrate by this is that dyno's are a great tuning tool, but the track is what tells the story. Long story short is I can't wait till we get some time to make some runs in Houston in more favorable conditions, as I think we'll put down some impressive numbers in favorable air.
As part of this testing we sent the LS6 heads off the car to Tony to put on his bench so that we could see what the heads make in comparison to the AFR heads we replaced them with. Suprisingly enough, our heads weren't too shabby. In fact I'd say they were probably one of the better set of heads Tony's tested. But, and this is a big but. They were nowhere near the "claimed" numbers we had promised on the heads by Jay. We'd been promised 320-330 cfm heads. In reality they were good, but nowhere near that good. Two ports were tested so we didn't have a realy good or a really bad port skew the numbers. The heads were thoroughly cleaned, etc... to ensure a fair test also.
…........….200….300….400….500….550….600… ….
1 3.900....131...194....252...290...302... 308......2 35cc
2 3.900....135...196....254...293...306... 313......2 35cc
2 4.125....136...198....259...302...316... 309......2 35cc (head went turbulent@.600)
AFR 205….145….210….257….290….301….308………205 cc’s
AFR 225….151….221….270….306….315….322………229 cc’s
Our heads were about on par with a 205 head, but the intake runner was 235 ccs vs 205 cc. The exhaust sides (which were re-done) by Greg Good were the best flowing exhaust side Tony had seen in a ported LS6 but were about 89cc. So, Greg managed to fix Jay's issues, he added a bit of volume in doing so, but as I said he did a really nice exhaust side.
……........200….300….400….500….600....... .....Volum e
1 3.900..128....172...204...227...241..... ........89 cc
2 3.900..126....179...215...232...245..... ........89 cc
2 4.125..133....176...225...248...256..... ........89 cc
AFR205….118….171….206….226….240……………..84 cc’s
AFR225….120….180….220….241….250……………..85 cc’s
We had planned to test an A&A vaccum pump on the car, but the kit was missing a hose, so we'll test that sometime in the near future. I'm hoping we'll have even better results to report....
I'm still puzzled as to what killed all the power in the car, but at this point, I can't argue with the results of the AFR heads. They just flat worked, and the car is running hard.
I'd like to take moment to thank all the guys @ MTI (Jayson, David, and Chris) who went way above and byond the call of duty and stayed until after 8PM at night to ensure the car was as good as it possibly could be. MTI is a great operation, and I can't say enough good things about them.
I'd like to give huge props to Tony Mamo who moved heaven and earth to get us a set of castings, and cranked out a "Mamo special" FAST 90 in record time. Like I said, Tony takes great pride in his work, and it shows...
Anyway, this could be a good place to jump off to discuss how important flow vs velocity is, and how important it is vs just raw flow numbers. Also how better cylinder filling may not show on the dyno, but may show up on the track. Just a few points we might want to discuss....
The current LS6 casting were originally done by Jay @ Absolute Speed. Last year the heads dropped a seat, so the heads were taken over to Greg Good here in Houston. Greg replaced all the seats in the heads. Greg also commented that the heads were "soft" on the exhaust side, so he touched up the exhaust side.
The car was put together last year, to be ready for Thunder. The car broke the rear on the first pass at Thunder with the Exedy clutch. After that, we made four passes in the car in Houston, and destroyed the Exedy clutch. The Exedy was replaced by a Textralia clutch. We made some passes in bad weather with the Textralia clutch and the car ran some 10.90's. Finally a few weeks ago, the car made a few laps at Motosports Ranch with Lou Sr. giving demo rides. In almost a year, thats all the time the car had on it....
So, we decided to make some changes to the car. In talking with Tony M. @ AFR, we had been planning to run a 225 head. Since we were in a time crunch to get the car ready for San Antonio, we decided to just run a 205 head since Lou had run them with pretty good success in his car last year.
Anyhow, Tony provided us witha set of milled 205's and a "Mamo-fied" FAST intake. The plan was to do a A-B swap on the car with no changes other than heads and observe the delta. Let me just say that Tony does a fantastic job on the FAST intake. He fixes some of the current issues with the manifold, and when you look up the port you can certainly see he's been busy up in there. When you compare the differneces to an out of the box FAST 90 the differences are glaring. Tony also has a nice hand, as the cosmetic side of his hand finished stuff really looks nice. While being pretty isn't always important, its certainly nice to see someone take real pride in their work.
The car was taken to MTI where all the work was performed. A baseline dyno was done of the car. As I said above, it had really no time on the motor a few passes and a few dyno pulls, and about 12 miles at the road course. Anyhow, a baseline dyno indicated that something was not right. The car had previously dyno'd 503RWHP at MTI. It was now showing about 460. A fresh set of plugs were installed along with an o2 sensor. Power dropped to 450. A cranking compression test showed about 178-182 psi on all cylinders. A leakdown test was the performed.
#1 - 15%
#2 - 6%
#3 - 7%
#4 - 12%
#5 - 11%
#6 - 8%
#7 - 9%
#8 - 8%
Hmmmmm.... Well, the tune was checked on the car, along with anything else that was readily visible. Nothing really looked off, except the power.
So it was decided since we we were running out of time to swap heads to see if we had an issue with the heads "going away". The heads and intake were swapped, and the combination was re-dynoed. The car made 487.4RWHP and 416.1 RWTQ with the belts on, and 492.9/425.2 with the belts off. The 503 RWHP graph has a small rev limiter bump in it, so the actual peak may not be 503. It may be around 500 or so. Also, MTI was only reving the car to 6800-6900. It'll make power to 7300, so there may be a bit of power up top not shown on the graph.
Anyhow, The fine folks at MTI buttoned up everything, and Jason tightened up the tune just a bit, and we were off to the races. I haven't seen the car in over 9 months, and haven't raced it competitively for almost 2 yrs. It's probably been 10 months since I made a full pass in the car. So, I was anxious to see what it was going to do.
My first impression of the car is that drivability was improved 1000%. The cam in the car is a BIG max effort cam from Ed Curtis. With the LS6 castings you had some low speed surge in first and second. This was not as big on a SD tune as you could load the car into 3rd or 4th and putt around. Once it was under load, it was fine. I noticed that with the 205s on the car all low speed surge is gone. Tip in and drivability was also greatly improved. I drove the car around in the pits creeping around in first with zero drama. I could have easily driven the car in traffic without having to do a lot of dancing on the clutch, etc...
We only had a couple of qualifying passes in the car before eliminations, so I didn't have a lot of time to sort out launch rpm, etc...But I have found that the Aussie clutch is probably the absolute best clutch we've ever had in the car, bar none. It grabs harder than the McLeod dual disc, and it lasted unlike the Exedy that was in the car. There was so much bite with the clutch, that the car was spinning. This may also be due to the fact that we have a set of ET Streets that were a year old.
Anyhow, our next order of business is to play with clutch slip and get the 60's back into the mid 1.4's We were cutting 1.5's all day in the car. I was simply launching the car as we always have, as like I said, I hadn't had time to do any testing to see wha the car might like. I also didn't have any time to test any real changes before eliminations.
DA was +2350 - +2400 on the weather station Even in those rather poor conditions, the car was making good power.
rev limiter @ 6900
60 - 1.5301
330 - 4.5809
1/8 - 7.0952
mph - 97.28
1000 - 9.2673
1/4 - 11.0798
mph - 127.01
60 - 1.5759
330 - 4.5487
1/8 - 7.0281
mph - 96.69
1000 - 9.1672
1/4 - 10.9675
mph - 127.70
Rev limiter @ 7400
60 - 1.5687
330 - 4.5548
1/8 - 7.0271
mph - 98.04
1000 - 9.4505
1/4 - 11.9251
mph - 85.62
(missed 4th on that pass)
60 - 1.5052
330 - 4.5164
1/8 - 7.0003
mph - 98.04
1000 - 9.1539
1/4 - 10.9575
mph - 127.44
60 - 1.5253
330 - 4.4827
1/8 - 6.9476
mph - 98.86
1000 - 9.0896
1/4 - 10.8822
mph - 128.28
60 - 1.5278
330 - 4.4979
1/8 - 6.9628
mph - 98.99
1000 - 9.1016
1/4 - 10.8925
mph - 128.39
So, this brings up several good points. The car is going faster in worse air with less indicated peak HP than it had previously. There are no huge midrange gains shown on the graphs. What I'd like to illustrate by this is that dyno's are a great tuning tool, but the track is what tells the story. Long story short is I can't wait till we get some time to make some runs in Houston in more favorable conditions, as I think we'll put down some impressive numbers in favorable air.
As part of this testing we sent the LS6 heads off the car to Tony to put on his bench so that we could see what the heads make in comparison to the AFR heads we replaced them with. Suprisingly enough, our heads weren't too shabby. In fact I'd say they were probably one of the better set of heads Tony's tested. But, and this is a big but. They were nowhere near the "claimed" numbers we had promised on the heads by Jay. We'd been promised 320-330 cfm heads. In reality they were good, but nowhere near that good. Two ports were tested so we didn't have a realy good or a really bad port skew the numbers. The heads were thoroughly cleaned, etc... to ensure a fair test also.
…........….200….300….400….500….550….600… ….
1 3.900....131...194....252...290...302... 308......2 35cc
2 3.900....135...196....254...293...306... 313......2 35cc
2 4.125....136...198....259...302...316... 309......2 35cc (head went turbulent@.600)
AFR 205….145….210….257….290….301….308………205 cc’s
AFR 225….151….221….270….306….315….322………229 cc’s
Our heads were about on par with a 205 head, but the intake runner was 235 ccs vs 205 cc. The exhaust sides (which were re-done) by Greg Good were the best flowing exhaust side Tony had seen in a ported LS6 but were about 89cc. So, Greg managed to fix Jay's issues, he added a bit of volume in doing so, but as I said he did a really nice exhaust side.
……........200….300….400….500….600....... .....Volum e
1 3.900..128....172...204...227...241..... ........89 cc
2 3.900..126....179...215...232...245..... ........89 cc
2 4.125..133....176...225...248...256..... ........89 cc
AFR205….118….171….206….226….240……………..84 cc’s
AFR225….120….180….220….241….250……………..85 cc’s
We had planned to test an A&A vaccum pump on the car, but the kit was missing a hose, so we'll test that sometime in the near future. I'm hoping we'll have even better results to report....
I'm still puzzled as to what killed all the power in the car, but at this point, I can't argue with the results of the AFR heads. They just flat worked, and the car is running hard.
I'd like to take moment to thank all the guys @ MTI (Jayson, David, and Chris) who went way above and byond the call of duty and stayed until after 8PM at night to ensure the car was as good as it possibly could be. MTI is a great operation, and I can't say enough good things about them.
I'd like to give huge props to Tony Mamo who moved heaven and earth to get us a set of castings, and cranked out a "Mamo special" FAST 90 in record time. Like I said, Tony takes great pride in his work, and it shows...
Anyway, this could be a good place to jump off to discuss how important flow vs velocity is, and how important it is vs just raw flow numbers. Also how better cylinder filling may not show on the dyno, but may show up on the track. Just a few points we might want to discuss....
11-21-2005, 02:46 PM
#2
Team Owner
Member Since: Apr 2001
Location: Elmhurst, IL (West Suburb of Chicago) & Home of MEGA Horsepower
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St. Jude Donor '06
Nice long informative write up J-ROD and nothing like having a 10 second, n/a, heads and cam, street driven Z06 with a stock bottom end. Congrats, best of luck and keep up the great work!!!!!! 
Last edited by Mopar Jimmy; 11-22-2005 at 12:39 AM.
11-21-2005, 11:43 PM
#6
Melting Slicks
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St. Jude Donor '05-'06
Awesome inforamtion as allways JRod! Whay gears??? How big a cam or maybe who made it or is it a custom grind? 
I am hoping for 10.99 after my HC swap and i have to get the 1.5s coming every time. I too love the Aussie clutch! Thanks brother!
Dave
I am hoping for 10.99 after my HC swap and i have to get the 1.5s coming every time. I too love the Aussie clutch! Thanks brother! Dave
11-22-2005, 01:32 AM
#9
Former Vendor
Originally Posted by Phil97SVT
Thats pretty huge MPH for the conditions. Doesnt that correct to 131/132mph @ -1000'?
Phil
Phil
A drop of 3000 feet in D/A is worth around 3.5 MPH. When I run at Famoso (versus LACR which is high desert), my car is consistently 4 MPH quicker and I usually see a net change in D/A of around 3500 feet typically (1500 vs. 5000 ish).
I cant wait to see what J-Rod can put down in the next few months with good weather and a tail wind!
Excellent results...great write-up
11-22-2005, 10:43 AM
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Originally Posted by chiefDave
How big a cam or maybe who made it or is it a custom grind?
Thanks brother!
Dave
Thanks brother!
Dave
Fairly good sized "Max-Effort" series grind.
Ed
11-22-2005, 10:46 AM
#14
Melting Slicks
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Ok, here is all the info on the car.
2002 Z06
M12
Textralia (Aussie) Clutch
Tunnel plate
DTE brace
DTE short shaft
DTE long shaft
DTE clutch pack
4.10 gears
LGM Headers/exhaust/stock Ti mufflers
LGM cage
LGM CF driveshaft
AFR 205s
AFR modified FAST 90
Morel lifters
Manton pushrods
Jesel Mohawk rockers
30# SVO injectors
stock fuel pump
GM90MM TB
Tuning by MTI
As for the cam. Its an Ed Curtis custom grind. It was worth about 10HP over the X3 it replaced.
The LS6 heads had been milled to 55cc's so, we milled the AFRs to match that. With as much overlap as we have we need some compression to keep DCR up. I really wouldn't recommend milling a head that much normally as I think in some cases it compromises the chamber design (thus flow). We'd have milled the AFR's less, but we didn't want to abnomally skew the test results by giving the LS6 heads 4% more based on the gains for compression.
The shortblock in the car right now is a forged one. When the seat fell out of the head it hit a piston and split a liner. We were in a bind for time, so we did a real quick forged motor. I tried to find a set of rods and pistons which would be close to the stock hypereutectic setup. With the help of Ed Curtis and Mark Oneal (the owner of Probe) we went with Probe who had the rods and pistons on the shelf and overnighted them to us (this happened just before the last Thunder shootout).
We lost some power going with a forged setup, but probably gained a bit of reliability. The pistons and rods are a bit heavier than the stockers, but about the lightest setup I could reasonalby find for an LS motor. We're running a flatop with a 2 eyebrow valve relief. The reliefs are a bit bigger than the flycut pistons we had so we lost a bit of CR there also.
The engine was done by Erik Koenig at HK Enterprises. It was assembled by Cameron who is now a machinist at MTI. Both of them are just top notch guys in my book.
I have an LS6 shortblock now, so if it comes into dispute that we have uber compression in the car, or whatever, because we have a forged bottom end right now, we'll simply put an LS6 shortblock in the car, and go duplicate our results... Heck we might even go faster with the lighter reciprocating mass...
Do I think the car will go faster? Yes, It think it'll go much faster. We were in 29.9 baro and almost 80 degree heat. Last Friday in Houston we had 30.4 and low 50's to mid 40's...
I raced Ls1joe in SA, he went 10.90 to our 10.88. Last Friday in decent air night he went 10.301 (with some suspension tuning, this was his new personal best). I think his best pass in SA was a 10.65. Anyhow, what I'm trying to say is that yes, if we get the car to the track in some decent air I think its going to fly.
As for the 225's yes, I'm hoping to try some at some point. We may also look at doing some other fun tests with the car.... I think the other thing we may look at doing soon enough is to swap in an aluminum flywheel from Textralia to pick up some gains there.
2002 Z06
M12
Textralia (Aussie) Clutch
Tunnel plate
DTE brace
DTE short shaft
DTE long shaft
DTE clutch pack
4.10 gears
LGM Headers/exhaust/stock Ti mufflers
LGM cage
LGM CF driveshaft
AFR 205s
AFR modified FAST 90
Morel lifters
Manton pushrods
Jesel Mohawk rockers
30# SVO injectors
stock fuel pump
GM90MM TB
Tuning by MTI
As for the cam. Its an Ed Curtis custom grind. It was worth about 10HP over the X3 it replaced.
The LS6 heads had been milled to 55cc's so, we milled the AFRs to match that. With as much overlap as we have we need some compression to keep DCR up. I really wouldn't recommend milling a head that much normally as I think in some cases it compromises the chamber design (thus flow). We'd have milled the AFR's less, but we didn't want to abnomally skew the test results by giving the LS6 heads 4% more based on the gains for compression.
The shortblock in the car right now is a forged one. When the seat fell out of the head it hit a piston and split a liner. We were in a bind for time, so we did a real quick forged motor. I tried to find a set of rods and pistons which would be close to the stock hypereutectic setup. With the help of Ed Curtis and Mark Oneal (the owner of Probe) we went with Probe who had the rods and pistons on the shelf and overnighted them to us (this happened just before the last Thunder shootout).
We lost some power going with a forged setup, but probably gained a bit of reliability. The pistons and rods are a bit heavier than the stockers, but about the lightest setup I could reasonalby find for an LS motor. We're running a flatop with a 2 eyebrow valve relief. The reliefs are a bit bigger than the flycut pistons we had so we lost a bit of CR there also.
The engine was done by Erik Koenig at HK Enterprises. It was assembled by Cameron who is now a machinist at MTI. Both of them are just top notch guys in my book.
I have an LS6 shortblock now, so if it comes into dispute that we have uber compression in the car, or whatever, because we have a forged bottom end right now, we'll simply put an LS6 shortblock in the car, and go duplicate our results... Heck we might even go faster with the lighter reciprocating mass...
Do I think the car will go faster? Yes, It think it'll go much faster. We were in 29.9 baro and almost 80 degree heat. Last Friday in Houston we had 30.4 and low 50's to mid 40's...
I raced Ls1joe in SA, he went 10.90 to our 10.88. Last Friday in decent air night he went 10.301 (with some suspension tuning, this was his new personal best). I think his best pass in SA was a 10.65. Anyhow, what I'm trying to say is that yes, if we get the car to the track in some decent air I think its going to fly.
As for the 225's yes, I'm hoping to try some at some point. We may also look at doing some other fun tests with the car.... I think the other thing we may look at doing soon enough is to swap in an aluminum flywheel from Textralia to pick up some gains there.
Last edited by J-Rod; 11-22-2005 at 10:49 AM.
11-22-2005, 11:00 AM
#15
Melting Slicks
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The valvetrain is pretty stable even at 7400.
Jesel of course makes the best rockers bar none...
Manton pushrods rock, they are strong and provide minimal deflection which to me is important.
Tony set us up with AFR's super spring which controlled the valvetrain nicely.
The lobe we are using isn't as agressive as an XE-R lobe, but is more agressive than an XE.
7400 is probably about the limit for this without having to do a lot more maintenance on the valvetrian. Erik and the guys at SAM were going much higher with a hyd. roller setup in Judson's car, but it required really keeping up with what you were doing.
Jesel of course makes the best rockers bar none...
Manton pushrods rock, they are strong and provide minimal deflection which to me is important.
Tony set us up with AFR's super spring which controlled the valvetrain nicely.
The lobe we are using isn't as agressive as an XE-R lobe, but is more agressive than an XE.
7400 is probably about the limit for this without having to do a lot more maintenance on the valvetrian. Erik and the guys at SAM were going much higher with a hyd. roller setup in Judson's car, but it required really keeping up with what you were doing.
11-22-2005, 11:03 AM
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Nice detailed post, JRod. Here is a link to a run by someone last week who has the X3 cam, AFR 205's, and the FAST 90/90 combo. He trapped 128+ as well. Granted, the DA was around -800, but it shows these heads make the power...which overcomes some of the comments by those who said they were strictly "dyno" heads. 
http://forums.corvetteforum.com/show...94&forum_id=90
http://forums.corvetteforum.com/show...94&forum_id=90
11-22-2005, 06:14 PM
#18
Former Vendor
"Dyno Queen"....
How I love that entire concept....just another excuse so the guys not putting down the numbers (on a chassis dyno) can sleep at night. An inertia style dyno represents a fixed mass that your driveline is forced to accelerate....no different concept than the fixed mass your engine is accelerating down the race track (your vehicle). My contention has been and always will be that a car capable of laying down a good number on an inertia style chassis dyno will be able to lay down a good number at the track with the right weather conditions, traction, launch technique and shifting abilities (assuming a manual equipped vehicle), and lets not forget raceweight which is obviously a huge factor to take into account
Is a car that makes less power capable of laying down impressive numbers (like close to stock Z's dipping in the 11's)...of course....because they have alot of the factors mentioned above working for them (air quality, traction, driver, weight, etc.).
Assuming the chassis dyno's that have produced "dyno queens" were all properly calibrated, every one of those car are capable of laying down a number in the right conditions....of course assuming no broken driveline components which is another topic all together.
Sorry this is off topic a bit....just felt like stirring the pot a little.
Tony M.
PS...
One last thing....Corrected numbers from a chassis dyno are of course all "relative" which I failed to mention. Meaning we all know an A4 with the same engine power at the flywheel will dyno less at the wheels....one with a race converter even less....lower gears (higher numerically) also less. My point is, however, that when comparing similar vehicles (driveline related) the "dyno queen" gets the nod every time to perform better if in fact it puts down more power to the tire when "corrected" on the chassis dyno. Again, assuming all the exact same "track parameters" mentioned above. There is ALOT more to putting up a low ET with a fat MPH then shear power alone....there are alot of variables and quite a few of them are out of our control (weather, traction, etc.)
How I love that entire concept....just another excuse so the guys not putting down the numbers (on a chassis dyno) can sleep at night. An inertia style dyno represents a fixed mass that your driveline is forced to accelerate....no different concept than the fixed mass your engine is accelerating down the race track (your vehicle). My contention has been and always will be that a car capable of laying down a good number on an inertia style chassis dyno will be able to lay down a good number at the track with the right weather conditions, traction, launch technique and shifting abilities (assuming a manual equipped vehicle), and lets not forget raceweight which is obviously a huge factor to take into account
Is a car that makes less power capable of laying down impressive numbers (like close to stock Z's dipping in the 11's)...of course....because they have alot of the factors mentioned above working for them (air quality, traction, driver, weight, etc.).
Assuming the chassis dyno's that have produced "dyno queens" were all properly calibrated, every one of those car are capable of laying down a number in the right conditions....of course assuming no broken driveline components which is another topic all together.
Sorry this is off topic a bit....just felt like stirring the pot a little.
Tony M.
PS...
One last thing....Corrected numbers from a chassis dyno are of course all "relative" which I failed to mention. Meaning we all know an A4 with the same engine power at the flywheel will dyno less at the wheels....one with a race converter even less....lower gears (higher numerically) also less. My point is, however, that when comparing similar vehicles (driveline related) the "dyno queen" gets the nod every time to perform better if in fact it puts down more power to the tire when "corrected" on the chassis dyno. Again, assuming all the exact same "track parameters" mentioned above. There is ALOT more to putting up a low ET with a fat MPH then shear power alone....there are alot of variables and quite a few of them are out of our control (weather, traction, etc.)
11-22-2005, 07:14 PM
#19
Le Mans Master
Originally Posted by J-Rod
Ok, here is all the info on the car.
2002 Z06
M12
Textralia (Aussie) Clutch
Tunnel plate
DTE brace
DTE short shaft
DTE long shaft
DTE clutch pack
4.10 gears
LGM Headers/exhaust/stock Ti mufflers
LGM cage
LGM CF driveshaft
AFR 205s
AFR modified FAST 90
Morel lifters
Manton pushrods
Jesel Mohawk rockers
30# SVO injectors
stock fuel pump
GM90MM TB
Tuning by MTI
As for the cam. Its an Ed Curtis custom grind. It was worth about 10HP over the X3 it replaced.
The LS6 heads had been milled to 55cc's so, we milled the AFRs to match that. With as much overlap as we have we need some compression to keep DCR up. I really wouldn't recommend milling a head that much normally as I think in some cases it compromises the chamber design (thus flow). We'd have milled the AFR's less, but we didn't want to abnomally skew the test results by giving the LS6 heads 4% more based on the gains for compression.
The shortblock in the car right now is a forged one. When the seat fell out of the head it hit a piston and split a liner. We were in a bind for time, so we did a real quick forged motor. I tried to find a set of rods and pistons which would be close to the stock hypereutectic setup. With the help of Ed Curtis and Mark Oneal (the owner of Probe) we went with Probe who had the rods and pistons on the shelf and overnighted them to us (this happened just before the last Thunder shootout).
We lost some power going with a forged setup, but probably gained a bit of reliability. The pistons and rods are a bit heavier than the stockers, but about the lightest setup I could reasonalby find for an LS motor. We're running a flatop with a 2 eyebrow valve relief. The reliefs are a bit bigger than the flycut pistons we had so we lost a bit of CR there also.
The engine was done by Erik Koenig at HK Enterprises. It was assembled by Cameron who is now a machinist at MTI. Both of them are just top notch guys in my book.
I have an LS6 shortblock now, so if it comes into dispute that we have uber compression in the car, or whatever, because we have a forged bottom end right now, we'll simply put an LS6 shortblock in the car, and go duplicate our results... Heck we might even go faster with the lighter reciprocating mass...
Do I think the car will go faster? Yes, It think it'll go much faster. We were in 29.9 baro and almost 80 degree heat. Last Friday in Houston we had 30.4 and low 50's to mid 40's...
I raced Ls1joe in SA, he went 10.90 to our 10.88. Last Friday in decent air night he went 10.301 (with some suspension tuning, this was his new personal best). I think his best pass in SA was a 10.65. Anyhow, what I'm trying to say is that yes, if we get the car to the track in some decent air I think its going to fly.
As for the 225's yes, I'm hoping to try some at some point. We may also look at doing some other fun tests with the car.... I think the other thing we may look at doing soon enough is to swap in an aluminum flywheel from Textralia to pick up some gains there.
2002 Z06
M12
Textralia (Aussie) Clutch
Tunnel plate
DTE brace
DTE short shaft
DTE long shaft
DTE clutch pack
4.10 gears
LGM Headers/exhaust/stock Ti mufflers
LGM cage
LGM CF driveshaft
AFR 205s
AFR modified FAST 90
Morel lifters
Manton pushrods
Jesel Mohawk rockers
30# SVO injectors
stock fuel pump
GM90MM TB
Tuning by MTI
As for the cam. Its an Ed Curtis custom grind. It was worth about 10HP over the X3 it replaced.
The LS6 heads had been milled to 55cc's so, we milled the AFRs to match that. With as much overlap as we have we need some compression to keep DCR up. I really wouldn't recommend milling a head that much normally as I think in some cases it compromises the chamber design (thus flow). We'd have milled the AFR's less, but we didn't want to abnomally skew the test results by giving the LS6 heads 4% more based on the gains for compression.
The shortblock in the car right now is a forged one. When the seat fell out of the head it hit a piston and split a liner. We were in a bind for time, so we did a real quick forged motor. I tried to find a set of rods and pistons which would be close to the stock hypereutectic setup. With the help of Ed Curtis and Mark Oneal (the owner of Probe) we went with Probe who had the rods and pistons on the shelf and overnighted them to us (this happened just before the last Thunder shootout).
We lost some power going with a forged setup, but probably gained a bit of reliability. The pistons and rods are a bit heavier than the stockers, but about the lightest setup I could reasonalby find for an LS motor. We're running a flatop with a 2 eyebrow valve relief. The reliefs are a bit bigger than the flycut pistons we had so we lost a bit of CR there also.
The engine was done by Erik Koenig at HK Enterprises. It was assembled by Cameron who is now a machinist at MTI. Both of them are just top notch guys in my book.
I have an LS6 shortblock now, so if it comes into dispute that we have uber compression in the car, or whatever, because we have a forged bottom end right now, we'll simply put an LS6 shortblock in the car, and go duplicate our results... Heck we might even go faster with the lighter reciprocating mass...
Do I think the car will go faster? Yes, It think it'll go much faster. We were in 29.9 baro and almost 80 degree heat. Last Friday in Houston we had 30.4 and low 50's to mid 40's...
I raced Ls1joe in SA, he went 10.90 to our 10.88. Last Friday in decent air night he went 10.301 (with some suspension tuning, this was his new personal best). I think his best pass in SA was a 10.65. Anyhow, what I'm trying to say is that yes, if we get the car to the track in some decent air I think its going to fly.
As for the 225's yes, I'm hoping to try some at some point. We may also look at doing some other fun tests with the car.... I think the other thing we may look at doing soon enough is to swap in an aluminum flywheel from Textralia to pick up some gains there.
11-23-2005, 10:46 AM
#20
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Member Since: Jul 2004
Location: Working in the shop 24/7 HI
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Originally Posted by Tony Mamo
One last thing....Corrected numbers from a chassis dyno are of course all "relative" which I failed to mention. Meaning we all know an A4 with the same engine power at the flywheel will dyno less at the wheels....one with a race converter even less....lower gears (higher numerically) also less. My point is, however, that when comparing similar vehicles (driveline related) the "dyno queen" gets the nod every time to perform better if in fact it puts down more power to the tire when "corrected" on the chassis dyno. Again, assuming all the exact same "track parameters" mentioned above. There is A LOT more to putting up a low ET with a fat MPH then shear power alone....there are a lot of variables and quite a few of them are out of our control (weather, traction, etc.)
When I'm going down the track, the car is accelerating. A faster accelerating combination should be faster than a lazy one with similar HP.. err.. I mean "dyno numbers". Don't you think?
Also... just like the "butcher's scale" at the meat market ... don't you think some dynos "can" lie if the operator has his finger on the scale too hard... or is that called the correction factor? Like comparing flow bench numbers in California and New York?
BTW... Where are you taking me and the wife for dinner at PRI? Better be a high priced restaurant so I can get "somewhat" even with you for all your abuse...
Ed