Putting together a l98ish combo
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Joined: Aug 2010
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From: Kaneohe Hi
Putting together a l98ish combo
OK gang heres the plan
AFR 195 heads pn 1040
2.05/1.6
Summit 1.6 rr
Comp Cams 08-305-8 cam
220 in 230 ex .510/.510 114 lsa
Lingenfelter superram with accel base
B&M holeshot 2000 torque converter
new pistons to 10-10.5/1
How dose that combo sound? im still up in the are about injector size but ill cover that with the tuner!
The top end is going togather in the next month or so and at that time ill have a better idea if i want to order a stroker crank or just new slugs for phase 2.
Here are my reservations. The torque converter, should i go a step higher to 2400-2600?i got it for free so its no loss if i flip it and guy another. I have a 700R4 with stock gears but plan to go 3.3X or so in the summer.
All of this for a 87 that is currently driven daily and would like to keep drive-ability ready for long trips on the highway and in town. but my goal is to hang with a stock C6 or may be even embarrass him abit, but i dont think ill bet there till i get the gears.
AFR 195 heads pn 1040
2.05/1.6
Summit 1.6 rr
Comp Cams 08-305-8 cam
220 in 230 ex .510/.510 114 lsa
Lingenfelter superram with accel base
B&M holeshot 2000 torque converter
new pistons to 10-10.5/1
How dose that combo sound? im still up in the are about injector size but ill cover that with the tuner!
The top end is going togather in the next month or so and at that time ill have a better idea if i want to order a stroker crank or just new slugs for phase 2.
Here are my reservations. The torque converter, should i go a step higher to 2400-2600?i got it for free so its no loss if i flip it and guy another. I have a 700R4 with stock gears but plan to go 3.3X or so in the summer.
All of this for a 87 that is currently driven daily and would like to keep drive-ability ready for long trips on the highway and in town. but my goal is to hang with a stock C6 or may be even embarrass him abit, but i dont think ill bet there till i get the gears.
Racer
Joined: Jul 2010
Posts: 308
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From: Kansas City MO
With that cam and pump gas and not having run the DCR numbers I'd guess you'd probably want to stay closer to the 10:1 compression ratio - it'll make good cylinder pressure and torque and have a good idle to boot.
The stock stall on a corvette is 2150 RPM IIRC so no need to downgrade to a 2000 RPM converter - I'd probably step up to a 2800-3000 RPM converter and it'll launch hard - otherwise just stick with the stock converter as that cam should be OK with a stock corvette converter's stall speed. As long as you retain the lockup functionality then cruise RPM will not change as the converter locks up and eliminates slippage when in 4th gear.
The stock stall on a corvette is 2150 RPM IIRC so no need to downgrade to a 2000 RPM converter - I'd probably step up to a 2800-3000 RPM converter and it'll launch hard - otherwise just stick with the stock converter as that cam should be OK with a stock corvette converter's stall speed. As long as you retain the lockup functionality then cruise RPM will not change as the converter locks up and eliminates slippage when in 4th gear.
Melting Slicks
Joined: Sep 2010
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your going to keep a stock crank
I would suggest a ZZ4 must be balanced.. or similar
26# injectors.. the heads 64cc ?? I would go with 10:5 - 10:8
step up to the 306 cam it's awesome
you will see the aftermarket intakes will need much more timing
10 - 12 deg
I would suggest a ZZ4 must be balanced.. or similar
26# injectors.. the heads 64cc ?? I would go with 10:5 - 10:8
step up to the 306 cam it's awesome
you will see the aftermarket intakes will need much more timing
10 - 12 deg
Safety Car
Joined: Feb 1999
Posts: 4,724
Likes: 16
From: Little Elm TX
OK gang heres the plan
AFR 195 heads pn 1040
2.05/1.6
Summit 1.6 rr
Comp Cams 08-305-8 cam
220 in 230 ex .510/.510 114 lsa
Lingenfelter superram with accel base
B&M holeshot 2000 torque converter
new pistons to 10-10.5/1
How dose that combo sound? im still up in the are about injector size but ill cover that with the tuner!
The top end is going togather in the next month or so and at that time ill have a better idea if i want to order a stroker crank or just new slugs for phase 2.
Here are my reservations. The torque converter, should i go a step higher to 2400-2600?i got it for free so its no loss if i flip it and guy another. I have a 700R4 with stock gears but plan to go 3.3X or so in the summer.
All of this for a 87 that is currently driven daily and would like to keep drive-ability ready for long trips on the highway and in town. but my goal is to hang with a stock C6 or may be even embarrass him abit, but i dont think ill bet there till i get the gears.
AFR 195 heads pn 1040
2.05/1.6
Summit 1.6 rr
Comp Cams 08-305-8 cam
220 in 230 ex .510/.510 114 lsa
Lingenfelter superram with accel base
B&M holeshot 2000 torque converter
new pistons to 10-10.5/1
How dose that combo sound? im still up in the are about injector size but ill cover that with the tuner!
The top end is going togather in the next month or so and at that time ill have a better idea if i want to order a stroker crank or just new slugs for phase 2.
Here are my reservations. The torque converter, should i go a step higher to 2400-2600?i got it for free so its no loss if i flip it and guy another. I have a 700R4 with stock gears but plan to go 3.3X or so in the summer.
All of this for a 87 that is currently driven daily and would like to keep drive-ability ready for long trips on the highway and in town. but my goal is to hang with a stock C6 or may be even embarrass him abit, but i dont think ill bet there till i get the gears.
The best I have seen out of that set-up was 11.6 @ 117 mph, he was running a 2800 rpm converter, 3.45 gears and old style AFR 190 cylinder heads, 219, with a ported Superram in a high mileage original 350. I was short of that with my 350, but I didn't keep that particular set-up around long enough to whittle it down.
As a note, I swapped from 3.07 to 3.45 gears on a near identical set-up and was rewarded with no improvement.
My results were similar to another forum member or two who tried the same. good luck with whatever you decide on.
Last edited by Beach Bum; Jan 24, 2011 at 03:05 PM.
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Joined: Aug 2010
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From: Kaneohe Hi
this summer it will be stroked to a 383 and likely a step up to the 306 cam at the same time.
how streetable will a 2800-3000 converter be? i can stand to lose some mpg but i dont want total pig street manors.
how streetable will a 2800-3000 converter be? i can stand to lose some mpg but i dont want total pig street manors.
Racer
Joined: Jul 2010
Posts: 308
Likes: 2
From: Kansas City MO
I had built a 96 S10 with a 406 and 700R4 with a 2800 stall and the stall was perfectly streetable and helped tame the cam a little bit in the driveability - under really light throttle it was just barely noticeable that there was that 'big' of a stall in it.
If you're really going to stroke it this summer then I really wouldn't waste my time with the smaller cam or any bottom end work (you mentioned "new pistons" - was that now or with the 383?)
Also - I would really consider doing the entire thing at once if you're only a couple months away to getting into the bottom end - have it apart once and be done and not have to purchase gaskets, coolant, etc. twice... Plus everything can go together outside the car and be stabbed in easily after the engine is done.
If you're really going to stroke it this summer then I really wouldn't waste my time with the smaller cam or any bottom end work (you mentioned "new pistons" - was that now or with the 383?)
Also - I would really consider doing the entire thing at once if you're only a couple months away to getting into the bottom end - have it apart once and be done and not have to purchase gaskets, coolant, etc. twice... Plus everything can go together outside the car and be stabbed in easily after the engine is done.
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Racer
Joined: Nov 2010
Posts: 460
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From: Oliphant Ontario
I can't comment on an L98 with that much stall, but I had a carb'd car with a 2800/3000 (was called a 2800 but would brake stand to about 3000) in it and it was ignorant in stop and go and parallel parking. Just seemed the engine was always screaming. The car (78 Camaro) also had a "shift kit" in it that didn't help. Engine basically hit 4000rpm before shifting even at light throttle and that caused a slap and pull every time.
I dropped to a 2400 stall which was much more streetable. The car being carb'd and well north of 400hp on a 350 was pretty flat down at the 2400 but I found doing a brake stand first that it would work up to about 2600/2700 and worked ok. If I were to drag the car only I would have kept the 3K but for spirited street driving I found the slight lag off the line to be more than made up by good drivability. Another side benefit that certainly wouldn't have helped 1/4 mile times but sure felt cool was doing a normal launch. Slight bog for 1rst 10 feet, then 15-20ft into it, the rear end lit up and smoked
Greg
I dropped to a 2400 stall which was much more streetable. The car being carb'd and well north of 400hp on a 350 was pretty flat down at the 2400 but I found doing a brake stand first that it would work up to about 2600/2700 and worked ok. If I were to drag the car only I would have kept the 3K but for spirited street driving I found the slight lag off the line to be more than made up by good drivability. Another side benefit that certainly wouldn't have helped 1/4 mile times but sure felt cool was doing a normal launch. Slight bog for 1rst 10 feet, then 15-20ft into it, the rear end lit up and smoked
Greg
Safety Car
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From: Little Elm TX
I recommend a transmission cooler regardless of what converter you choose. They're cheap at under $ 100 and quick n easy to install. If you're doing significant street & highway driving, I do recommend a lock-up converter as well.
Racer
Joined: Nov 2010
Posts: 460
Likes: 1
From: Oliphant Ontario
Agree on the lock up, if the Camaro had one it might have made enough difference. Of course in the long run, a TH350 didn't last behind the motor and I swapped in a stick and couldn't have liked it better.
Thread Starter
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Joined: Aug 2010
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From: Kaneohe Hi
thanks gang, i knew that the vette converter was higher than many other applications but dident know it was that high glad i got it for free and dident get into a rush to install it. 2800 here i come. im just going to suck it up and get the stroker kit and do it all at once and ill return the 305 cam back to summit as they have a 30 day exchange window is is the 08-306-8 a "small base" cam? or will i need a custom grind?
Pro
Joined: Jun 2005
Posts: 583
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From: USA
are you going to order the heads from AFR? if so, are you going to get them angle-milled by AFR so you don't lose too much on the compression?
since the C4 cyl hds have a 58cc combustion chamber and most aftermarket heads start with 64cc...
my understanding is that the factory head gasket was 0.051" thick (pretty thick), but even if you went with a 0.038" head gasket, you still wouldn't make up the difference with a 64cc head (everything else being the same").
if you have your local machine shop do the head milling to make up that much difference, i think then that the intake manifold bolt holes and intake manifold face get weird.
I'm contemplating the same damn thing myself right now.
Summit has a pretty easy-to-use compression ratio calculator that you can play around with this scenario.
http://www.summitracing.com/expertad...=calcsandtools
since the C4 cyl hds have a 58cc combustion chamber and most aftermarket heads start with 64cc...
my understanding is that the factory head gasket was 0.051" thick (pretty thick), but even if you went with a 0.038" head gasket, you still wouldn't make up the difference with a 64cc head (everything else being the same").
if you have your local machine shop do the head milling to make up that much difference, i think then that the intake manifold bolt holes and intake manifold face get weird.
I'm contemplating the same damn thing myself right now.
Summit has a pretty easy-to-use compression ratio calculator that you can play around with this scenario.
http://www.summitracing.com/expertad...=calcsandtools
Thread Starter
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Joined: Aug 2010
Posts: 74
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From: Kaneohe Hi
are you going to order the heads from AFR? if so, are you going to get them angle-milled by AFR so you don't lose too much on the compression?
since the C4 cyl hds have a 58cc combustion chamber and most aftermarket heads start with 64cc...
my understanding is that the factory head gasket was 0.051" thick (pretty thick), but even if you went with a 0.038" head gasket, you still wouldn't make up the difference with a 64cc head (everything else being the same").
if you have your local machine shop do the head milling to make up that much difference, i think then that the intake manifold bolt holes and intake manifold face get weird.
I'm contemplating the same damn thing myself right now.
Summit has a pretty easy-to-use compression ratio calculator that you can play around with this scenario.
http://www.summitracing.com/expertad...=calcsandtools
since the C4 cyl hds have a 58cc combustion chamber and most aftermarket heads start with 64cc...
my understanding is that the factory head gasket was 0.051" thick (pretty thick), but even if you went with a 0.038" head gasket, you still wouldn't make up the difference with a 64cc head (everything else being the same").
if you have your local machine shop do the head milling to make up that much difference, i think then that the intake manifold bolt holes and intake manifold face get weird.
I'm contemplating the same damn thing myself right now.
Summit has a pretty easy-to-use compression ratio calculator that you can play around with this scenario.
http://www.summitracing.com/expertad...=calcsandtools
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i had the same concerns about loss of CR going from a 58cc to a 65cc chanber. but from what i have read is that the loss of compression is more that made up from the increased flow of the newer heads. Chevy High Perforce ran a series The Goodwrench Quest. In part 4 they ran "ported corvette aluminum heads" and then with bog stock 609 vortec castings. again 58cc to 64cc as you and i are doing, a loss in compression ratio but better flowing heads. they lost 4 hp under 3900rpm but gained nearly 40 over the ported 113's in the top end. i will leave them as they are and go with the flow that will make more power i think the AFR's flow around 240 @.500 but he stock 113' castings are around 200 at the same lift
Same with me although I decided on the Victor Reinz .026" gaskets to claw back a bit of that lost compression. Of course, I then decided to stroke and go with forged flat tops so will now need to go with something the thickness of the stock gasket to keep the SCR within reason.
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From: Kaneohe Hi
Same with me although I decided on the Victor Reinz .026" gaskets to claw back a bit of that lost compression. Of course, I then decided to stroke and go with forged flat tops so will now need to go with something the thickness of the stock gasket to keep the SCR within reason.
Team Owner
Joined: Oct 2004
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From: altered state
St. Jude Donor '05
I built a sbc with similar logic, the head and compression/flow thing.
If I had the $ Id rip it apart and give it the CR it wants would be a totally different animal. You CAN do it like those articles say but not always a good idea. One thing to do a dyno pull, another to have to live with it on a daily basis
Add the compression to it, the motor is going to want it let me say that.
Your car is apart, easy to take 150 or whatever have them milled now.
Your motor will act much better so it gives you what youd hope for.
If, with those pistons at 0 deck your CR falls around 10.5 you should be Ok.
Check with the mfr, some figure compression ratio with a given head CC and figure the piston is down in the hole so far (say 25 thou or stock?) for arguements sake, others with it at 0 deck. If your compression falls down in the 9s somewhere your car wont like it with that cam.
So check into that part, many "10 or 11 to 1"motors out there that really only have 9-9/5 to 1 and dont run
If I had the $ Id rip it apart and give it the CR it wants would be a totally different animal. You CAN do it like those articles say but not always a good idea. One thing to do a dyno pull, another to have to live with it on a daily basis
Add the compression to it, the motor is going to want it let me say that.
Your car is apart, easy to take 150 or whatever have them milled now.
Your motor will act much better so it gives you what youd hope for.
If, with those pistons at 0 deck your CR falls around 10.5 you should be Ok.
Check with the mfr, some figure compression ratio with a given head CC and figure the piston is down in the hole so far (say 25 thou or stock?) for arguements sake, others with it at 0 deck. If your compression falls down in the 9s somewhere your car wont like it with that cam.
So check into that part, many "10 or 11 to 1"motors out there that really only have 9-9/5 to 1 and dont run
Last edited by cv67; Jan 25, 2011 at 08:28 PM.
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From: Overland Park Kansas
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Not sure why you wouldn't put a 383 crank in right away. With the need for new pistons anyway, you're already crackin' into the block.
