Critique my cam idea - Autocross/HPDE/Street car
#1
Racer
Thread Starter
Critique my cam idea - Autocross/HPDE/Street car
Currently my 1999 FRC makes 348/352 TQ with the following modifications for power (some more than others, haha):
XS Longtubes w/cats
Corsa Catback
Blackwing Intake
85MM Maf
Cleaned up TB and Dorman LS2 intake
Other stuff:
42lb GM injectors
McLeod RST and Flywheel
Suspension + brake goodies
For fun I also flipped it over to flex fuel using a 04 Tahoe PCM and it made 352/360 on a dyno running around E50. As I am moving to east Texas I don't expect to be able to run Ethanol fuel unless I ship it in by the barrel so will probably go back to the stock pcm next year.
Ideally I want to move the power curve up and be able to throw in a cam/spring/pushrod combo and leave it for a few years. Eventually I'll send my 853's off to be ported or throw on some 59-61cc setup 243 heads. I think with a proper cam and and underdrive pulley I can crack 380/380 maybe even 400/400 if I can find a happy dyno. I enjoy autocross and want to start HPDE work. The drag strip is fun, but I always end up bracket racing so it "runs what it runs".
What I've come up with so far would be a custom comp cam grind using the 3673/3757 lobe combo.
Should be put at a 225/236 .570, .544 and I would set it on a 111 LSA + 3.5 advance ground in so I can just toss it in and go (after measuring of course).
My theory is this should bump the torque curve up from around 2200+. With me still having stock rod bolts I am always out of it at 6400rpm and have the limiter usually set at 6200 actually.
Interested in hearing thoughts and experiences. Essentially this is my version of a "mid lift" GM ASA cam on steroids. I've moved around the valve timing events to target a DCR of 7.68 on the stock heads, 8.68 with future 243's on a 59cc chamber.
Thanks for stopping by!
-Josh
XS Longtubes w/cats
Corsa Catback
Blackwing Intake
85MM Maf
Cleaned up TB and Dorman LS2 intake
Other stuff:
42lb GM injectors
McLeod RST and Flywheel
Suspension + brake goodies
For fun I also flipped it over to flex fuel using a 04 Tahoe PCM and it made 352/360 on a dyno running around E50. As I am moving to east Texas I don't expect to be able to run Ethanol fuel unless I ship it in by the barrel so will probably go back to the stock pcm next year.
Ideally I want to move the power curve up and be able to throw in a cam/spring/pushrod combo and leave it for a few years. Eventually I'll send my 853's off to be ported or throw on some 59-61cc setup 243 heads. I think with a proper cam and and underdrive pulley I can crack 380/380 maybe even 400/400 if I can find a happy dyno. I enjoy autocross and want to start HPDE work. The drag strip is fun, but I always end up bracket racing so it "runs what it runs".
What I've come up with so far would be a custom comp cam grind using the 3673/3757 lobe combo.
Should be put at a 225/236 .570, .544 and I would set it on a 111 LSA + 3.5 advance ground in so I can just toss it in and go (after measuring of course).
My theory is this should bump the torque curve up from around 2200+. With me still having stock rod bolts I am always out of it at 6400rpm and have the limiter usually set at 6200 actually.
Interested in hearing thoughts and experiences. Essentially this is my version of a "mid lift" GM ASA cam on steroids. I've moved around the valve timing events to target a DCR of 7.68 on the stock heads, 8.68 with future 243's on a 59cc chamber.
Thanks for stopping by!
-Josh
Last edited by niterydr; 10-19-2018 at 05:17 PM.
#3
Racer
Thread Starter
3.42 still and 3300 with driver.
#4
Drifting
that's quite a lot of cam to be all in at 6200rpm...I know the asa cam says 2000rpm to 6000rpm but past testing shows that is doesn't drop off until 6800 .......but I get it with the rod bolts... I'm thinking the cam motion titan3 may be more in the wheelhouse. especially on a 5.7L with unported 853's and 3.42's...because you dident mention changing out lifters.. (Johnson ) It sounds like you don't want to pull the heads.....But if you can put in .040 head gaskets to tighten up the quelsh that would also help with pump gas..........with a "mid lift" the .010 should not affect piston to valve clearance..... with LS6 heads the rodbolts will need to be addressed.... then I think more cam is easier to justify...sorry if this seems all over the place.. I'm just thinking this thru.... anyways just my .02.... please post results of what you decide to do.
#5
Racer
Thread Starter
Good input for sure. You are correct that I really don't want to crack into the longblock and if I do it will be a head swap or cnc work for sure. Then I may as well pull the shortblock and do bolts, then may as well rebuild it....afraid I will open Pandora's box (I tend to keep rolling when I get into something so would rather leave well enough alone for now).
I don't think "my" cam will carry out much past 6500 so it keeps me civil with reving for sure. To me under the curve is more important than peak power, I actually did look at the titan 3 but I think that the extra lift will only gain me address valvetrain stress for minimal gains? I've heard great things about cam motion, but not sure that's the one for me.
I do wonder how that cams powerband lines up versus my suggestion in the original post, I fear it is pretty far "right".
I'll post up whatever I do, makes it fun for all!
I don't think "my" cam will carry out much past 6500 so it keeps me civil with reving for sure. To me under the curve is more important than peak power, I actually did look at the titan 3 but I think that the extra lift will only gain me address valvetrain stress for minimal gains? I've heard great things about cam motion, but not sure that's the one for me.
I do wonder how that cams powerband lines up versus my suggestion in the original post, I fear it is pretty far "right".
I'll post up whatever I do, makes it fun for all!
Last edited by niterydr; 10-19-2018 at 08:36 PM. Reason: Extra words and generally getting beat by my phone's autocorrect
#6
Burning Brakes
Do the cam. These engines deserve a nice cam. A friend of mine did a cam in his 1999 frc and ran autocross and road courses all the time. His car did great. I'm currently doing a cam in my 2000 frc.
#7
Racer
Thread Starter
What did he run? What are you putting in?
Last edited by niterydr; 10-20-2018 at 06:24 AM.
#8
Racer
Thread Starter
I downloaded Engine Analyzer Pro v3.9 and started to run some of these through the program. After further analysis my above thought is being penciled out. New ideas:
219/225 .564/.570 (108 +4 3670/3673) Xtreme RPR
This one seemed to have the highest average TQ and HP but I struggle with the 108 + 4 lsa with those valve events. IVC is 33.5 (versus 36.5 on the stock cam) so I worry that curve will be to far to the left, peak power calculates to 6100 but I think it would be more around 5800 with a nose dive. I can't find anyone in the U.S running a 104 ICL and a 6 degree overlap to see if it would even idle on a MAF. I bet it would lope like hell though and have a lot of punch.
217/223 .563/.568 (110+2 3669/3672) Xtreme RPR
With my components into the calculator I give up -2 tq average, -3 tq peak (same rpm - 4340rpm), -1 hp average and gain +1 hp at calculated peak (same rpm - 6100rpm). ICL is a more tame 108, 0 degree overlap and IVC is same as factory 36.5. Pretty confident this would idle well and pull probably strong to about 6400 or so.
A cheap shelf cam available is Elgin 1839 P
220/224 .575/.575 (112 +4). This calculates out to have softer lobes versus either of the spec'd Xtreme RPR cams which should promote longer valve spring life. The higher lift means I'll have to run a PAC 1218 or similar and can't get away with the yellow LS6 springs, but the 1218 or the 1219 (or equivalent) should last awhile. This cam is down roughly -5 tq average (but still up +17 over my current car) and down -9 tq peak @ 4340rpm. Average HP is down -3hp from the "max effort torque monster" above with the same peak power calculated (and still calculating to be a +18 hp average increase). These cams are super cheap it appears, not sure on durability.
Any thoughts?
219/225 .564/.570 (108 +4 3670/3673) Xtreme RPR
This one seemed to have the highest average TQ and HP but I struggle with the 108 + 4 lsa with those valve events. IVC is 33.5 (versus 36.5 on the stock cam) so I worry that curve will be to far to the left, peak power calculates to 6100 but I think it would be more around 5800 with a nose dive. I can't find anyone in the U.S running a 104 ICL and a 6 degree overlap to see if it would even idle on a MAF. I bet it would lope like hell though and have a lot of punch.
217/223 .563/.568 (110+2 3669/3672) Xtreme RPR
With my components into the calculator I give up -2 tq average, -3 tq peak (same rpm - 4340rpm), -1 hp average and gain +1 hp at calculated peak (same rpm - 6100rpm). ICL is a more tame 108, 0 degree overlap and IVC is same as factory 36.5. Pretty confident this would idle well and pull probably strong to about 6400 or so.
A cheap shelf cam available is Elgin 1839 P
220/224 .575/.575 (112 +4). This calculates out to have softer lobes versus either of the spec'd Xtreme RPR cams which should promote longer valve spring life. The higher lift means I'll have to run a PAC 1218 or similar and can't get away with the yellow LS6 springs, but the 1218 or the 1219 (or equivalent) should last awhile. This cam is down roughly -5 tq average (but still up +17 over my current car) and down -9 tq peak @ 4340rpm. Average HP is down -3hp from the "max effort torque monster" above with the same peak power calculated (and still calculating to be a +18 hp average increase). These cams are super cheap it appears, not sure on durability.
Any thoughts?
#9
Team Owner
106 ICL is about as aggressive as I've found on a LS
https://ls1tech.com/forums/dynamometer-results-comparisons/184018-224-224-561-561-110lsa-4-h-c-dyno-results-inside.html
https://ls1tech.com/forums/generation-iii-internal-engine/72972-224-224-110lsa-106icl-cam-dyno-results-very-happy.html
https://ls1tech.com/forums/dynamometer-results-comparisons/184018-224-224-561-561-110lsa-4-h-c-dyno-results-inside.html
https://ls1tech.com/forums/generation-iii-internal-engine/72972-224-224-110lsa-106icl-cam-dyno-results-very-happy.html
Last edited by 93Polo; 10-22-2018 at 12:43 PM.
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niterydr (10-22-2018)
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niterydr (10-23-2018)
#11
Team Owner
What are your concerns? Emissions, spring life, broad torque curve, idle/driveability?
If you are running track events most say to try to keep it to 6200rpm or less with the factory wet sump due to the pump design. I wouldn't be concerned about the rod bolts at your power level.
I am a CamMotion fan having made good torque and not killed springs with them. My old Futral (CamMotion) 228/230 went 30k miles and some track events between springs with the limiter set at 7k. A close friend has run 2 seasons or 6-8 events with a CamMotion Titan 4 (227/232). I would call CamMotion, and EPS (Engine Power Systems) and discuss your ideas. I would degree the cam in, especially if you go Comp.
I like the specs on the bottom 2 but have no experience with Elgin. However if emissions are not a concern IMO there is little trade off in going with a intake duration in the mid 220s. Also, lift isn't everything went it comes to valve spring life, ramp rates play a large part in it too.
If you are running track events most say to try to keep it to 6200rpm or less with the factory wet sump due to the pump design. I wouldn't be concerned about the rod bolts at your power level.
I am a CamMotion fan having made good torque and not killed springs with them. My old Futral (CamMotion) 228/230 went 30k miles and some track events between springs with the limiter set at 7k. A close friend has run 2 seasons or 6-8 events with a CamMotion Titan 4 (227/232). I would call CamMotion, and EPS (Engine Power Systems) and discuss your ideas. I would degree the cam in, especially if you go Comp.
I like the specs on the bottom 2 but have no experience with Elgin. However if emissions are not a concern IMO there is little trade off in going with a intake duration in the mid 220s. Also, lift isn't everything went it comes to valve spring life, ramp rates play a large part in it too.
Last edited by 93Polo; 10-23-2018 at 04:51 PM.
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niterydr (10-23-2018)
#12
Racer
Thread Starter
What are your concerns? Emissions, spring life, broad torque curve, idle/driveability?
If you are running track events most say to try to keep it to 6200rpm or less with the factory wet sump due to the pump design. I wouldn't be concerned about the rod bolts at your power level.
I am a CamMotion fan having made good torque and not killed springs with them. My old Futral (CamMotion) 228/230 went 30k miles and some track events between springs with the limiter set at 7k. A close friend has run 2 seasons or 6-8 events with a CamMotion Titan 4 (227/232). I would call CamMotion, and EPS (Engine Power Systems) and discuss your ideas. I would degree the cam in, especially if you go Comp.
I like the specs on the bottom 2 but have no experience with Elgin. However if emissions are not a concern IMO there is little trade off in going with a intake duration in the mid 220s. Also, lift isn't everything went it comes to valve spring life, ramp rates play a large part in it too.
If you are running track events most say to try to keep it to 6200rpm or less with the factory wet sump due to the pump design. I wouldn't be concerned about the rod bolts at your power level.
I am a CamMotion fan having made good torque and not killed springs with them. My old Futral (CamMotion) 228/230 went 30k miles and some track events between springs with the limiter set at 7k. A close friend has run 2 seasons or 6-8 events with a CamMotion Titan 4 (227/232). I would call CamMotion, and EPS (Engine Power Systems) and discuss your ideas. I would degree the cam in, especially if you go Comp.
I like the specs on the bottom 2 but have no experience with Elgin. However if emissions are not a concern IMO there is little trade off in going with a intake duration in the mid 220s. Also, lift isn't everything went it comes to valve spring life, ramp rates play a large part in it too.
I would say power under 6500 (6200) as I don't really want to open the motor and go down that path just yet, if I do I may go with a bigger cubic inch base to start.
Then next would be spring life as I'd like to get 20k out of a set (1-2 seasons) or better, ideally better than 30k miles but will make it happen if I get 10k out of a set and they are reasonably priced (I'll bucket the cost of springs into consumables).
I have a twin disc clutch and am comfortable tuning it, so drive ability around 1500+rpm is needed, I can "make due" if it is nasty to get it to idle. Granted I've never had to dial in a really nasty V8 but I've done my fare share of no idle controller,,280+ degree duration 4 cylinders with garden hoses for injectors over the years....
I want torque. All of it.
Just sent a request to cam motion for their input.
Last edited by niterydr; 10-23-2018 at 06:49 PM.
#13
Team Owner
I am moving to east Texas so I don't give a rip about emissions (reason why I haven't cammed it yet, waiting to see where the wife ended up getting a job at).
I would say power under 6500 (6200) as I don't really want to open the motor and go down that path just yet, if I do I may go with a bigger cubic inch base to start.
Then next would be spring life as I'd like to get 20k out of a set (1-2 seasons) or better, ideally better than 30k miles but will make it happen if I get 10k out of a set and they are reasonably priced (I'll bucket the cost of springs into consumables).
I have a twin disc clutch and am comfortable tuning it, so drive ability around 1500+rpm is needed, I can "make due" if it is nasty to get it to idle. Granted I've never had to dial in a really nasty V8 but I've done my fare share of no idle controller,,280+ degree duration 4 cylinders with garden hoses for injectors over the years....
I want torque. All of it.
Just sent a request to cam motion for their input.
I would say power under 6500 (6200) as I don't really want to open the motor and go down that path just yet, if I do I may go with a bigger cubic inch base to start.
Then next would be spring life as I'd like to get 20k out of a set (1-2 seasons) or better, ideally better than 30k miles but will make it happen if I get 10k out of a set and they are reasonably priced (I'll bucket the cost of springs into consumables).
I have a twin disc clutch and am comfortable tuning it, so drive ability around 1500+rpm is needed, I can "make due" if it is nasty to get it to idle. Granted I've never had to dial in a really nasty V8 but I've done my fare share of no idle controller,,280+ degree duration 4 cylinders with garden hoses for injectors over the years....
I want torque. All of it.
Just sent a request to cam motion for their input.
Some reading
https://ls1tech.com/forums/generatio...-race-cam.html
I'd call Geoff at EPS
Last edited by 93Polo; 10-23-2018 at 09:21 PM.
#14
Racer
Thread Starter
I have one recommendation in from cam motion 224/230 112+3 .612/.595
With double valve springs it shoukd last a long time. Punching it into the simulator it doesn't seem to gain much which tells me maybe one of my parameters is off on the simulator as others have seemed to done well with this cam.
With double valve springs it shoukd last a long time. Punching it into the simulator it doesn't seem to gain much which tells me maybe one of my parameters is off on the simulator as others have seemed to done well with this cam.
#15
Drifting
I have one recommendation in from cam motion 224/230 112+3 .612/.595
With double valve springs it shoukd last a long time. Punching it into the simulator it doesn't seem to gain much which tells me maybe one of my parameters is off on the simulator as others have seemed to done well with this cam.
With double valve springs it shoukd last a long time. Punching it into the simulator it doesn't seem to gain much which tells me maybe one of my parameters is off on the simulator as others have seemed to done well with this cam.
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niterydr (11-02-2018)
#16
Melting Slicks
Since you are looking for a HPDE/autocross cam you should key on the torque specs in the 3500-5500 rpm range. This is where you will do most of your acceleration in both type of events. If you do more HPDE than AutoX then you want good pulling power to 6200 rpm.
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niterydr (11-02-2018)
#17
Team Owner
Some favor the 224/230 believing it provides the strong torque of the mid size 224 cams but the extra exhaust duration keeps the power carrying in the upper RPMs. LG and EPS also like longer exhaust duration on their cams. It wouldn't surprise me if EPS recommended their 226/234. The ASA cam also has 10 degrees more on the exhaust.
I like the 224/230 and the 227/232 but it also depends on Autox or HPDE
I like the 224/230 and the 227/232 but it also depends on Autox or HPDE
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niterydr (11-02-2018)
#18
Safety Car
I would call and talk to people like Brian Tooley, Lingenfelter, Comp Cams etc about a cam selection for your application.
#19
Racer
Thread Starter
Update for the search feature:
I ended up talking to Texas Speed and going with the PRC 225 as cast heads and a 228/232 on the 112 LSA (112+2). Excited to see how this moves.
With moving to East Texas my opportunity for autocross is greatly diminished, so pivoting the vehicle use more towards drag strip/large road course. If there isn't enough hit at 3500 I'll just put in 390 gears.
I ended up talking to Texas Speed and going with the PRC 225 as cast heads and a 228/232 on the 112 LSA (112+2). Excited to see how this moves.
With moving to East Texas my opportunity for autocross is greatly diminished, so pivoting the vehicle use more towards drag strip/large road course. If there isn't enough hit at 3500 I'll just put in 390 gears.
#20
Safety Car
Please get another suggestion aside from Texas Speed...