California Super Ram Combo
Drifting
Joined: Oct 2006
Posts: 1,934
Likes: 3
From: Citrus Heights California
I ran your set-up for years when I lived in California. It smogged clean as a whistle, just have everything hooked up and a cat installed. They are right about the headers, none have carb #'s, you can get a few inspection shops to overlook it, its just a visual thing..... consider tipping. :o I always had an adjustable fuel regulator, but never had that questioned..... or even looked at.
Your set-up is very good for building exceptional midrange torque..... it took my 85 to mid to low 11's at close to 120 mph. Your throttle response will be extremely snappy.... You should be able to make around 450 HP @ 5700 rpm - 500 ftlbs @ 4000 rpm with that set-up, maybe even a bit more HP if you port your SR intake..... thats enough power for very deep 11's if you're able to optimize.
As a note, your 24lb injectors are fine, I ran the Ford SVO 24lb injectors.... didn't even turn up the pressure.... tried it a few times with up and around 50 psi, but it didn't go any faster so brought back down to around 42-44 psi.
good luck
Your set-up is very good for building exceptional midrange torque..... it took my 85 to mid to low 11's at close to 120 mph. Your throttle response will be extremely snappy.... You should be able to make around 450 HP @ 5700 rpm - 500 ftlbs @ 4000 rpm with that set-up, maybe even a bit more HP if you port your SR intake..... thats enough power for very deep 11's if you're able to optimize.
As a note, your 24lb injectors are fine, I ran the Ford SVO 24lb injectors.... didn't even turn up the pressure.... tried it a few times with up and around 50 psi, but it didn't go any faster so brought back down to around 42-44 psi.
good luck
Last year was different. The smog techs are getting hit with fines for overlooking things and are very paranoid.
Last year my 88 passed the emissions test and still failed the visual because of an adjustable fuel pressure regulator. They are getting very nit picky.
My L98 runs fine with a stock fuel pressure regulator, 24 lb. Trickflow injectors and a custom tune. I think the stock pressure is 44 lbs. The guy that tuned my 88 said he can size any combo and dial it in. I think 24 lb. injectors will be fine. Take the advice of the people that have already run this combo successfully.
Safety Car
Joined: Oct 2008
Posts: 4,022
Likes: 30
From: Los Angeles CA
What percent do you add to find crank HP? or the other way around?
Race Director
Joined: Nov 2003
Posts: 12,221
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From: Overland Park Kansas
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For manual cars that don't have "extra" restriction, I take 17% off crank #'s to estimate what gets to the ground.
Then, remove more for elements that aren't ideal and a bit for accessories. (Because of your exhaust, you might be another 5% off crank. Just a guess tho.)
Then, remove more for elements that aren't ideal and a bit for accessories. (Because of your exhaust, you might be another 5% off crank. Just a guess tho.)
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
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My L98 runs fine with a stock fuel pressure regulator, 24 lb. Trickflow injectors and a custom tune. I think the stock pressure is 44 lbs. The guy that tuned my 88 said he can size any combo and dial it in. I think 24 lb. injectors will be fine. Take the advice of the people that have already run this combo successfully.
My preference is to do like you did and pick an injector on the smaller side to insure good pressure and DC (e.g., Ford 24lbs units -- that shoot ~25.6lbs in our rails). While something like 36-42lb injectors could be made to work, I'm skeptical about that being a good option.
Safety Car
Joined: Oct 2008
Posts: 4,022
Likes: 30
From: Los Angeles CA
By the way Slick I just downloaded the E.O. for the TPiS adjustable fuel pressure regulator. It is definitely CA legal. Has been since 1991. With a 268XFI or LPE 219 cam and the AFPR, I should be able to use my 24# Bosche III's. Did you step up to the 1,000 CFM throttle body? It's legal too.
you can mimic that with a faster foot smaller hole.
this is my understanding, but let the real guru's comment.
Thread Starter
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
Interesting. I thought the 85 stock throttle body was 660 CFM. If it is 850, you're right. 850 is a pretty big carb. There's not a lot more to be gained by the 1000 CFM and it is costly.
Le Mans Master
Joined: Dec 2002
Posts: 5,270
Likes: 3
From: Seattle Area WA
Race Director
Joined: Nov 2003
Posts: 12,221
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
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Slick might be thinking of the 52mm -- thinking 850cfm.
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Safety Car
Joined: Oct 2008
Posts: 4,022
Likes: 30
From: Los Angeles CA
650-660cfm has been posted around here quite a bit too. But, after finding this test, 780cfm might be "the number". (Unless an '85 unit is lower than what was measured???) Seems like there's some minor differences in the TPI TB units for IAC. So, it's possible that earlier units could be lower.
Slick might be thinking of the 52mm -- thinking 850cfm.
Slick might be thinking of the 52mm -- thinking 850cfm.
and besides I have an airfoil, I guess that test busts that myth that airfoils don't do diddly...
what would be the symtoms if the TB was too small? inability to rev?
that's not a problem with my car, plausibly the huge plenum with the SR, is a big hopper and does not run out of air molecules as soon as someting with fewer cubic inches like a smaller plenum (stock) or miniram type.
Last edited by slickfx3; Jun 9, 2009 at 02:05 AM.
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
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No I was under the impression the 48 flowed 850, hence my not needing to spend more money
and besides I have an airfoil, I guess that test busts that myth that airfoils don't do diddly...
what would be the symtoms if the TB was too small? inability to rev?
that's not a problem with my car, plausibly the huge plenum with the SR, is a big hopper and does not run out of air molecules as soon as someting with fewer cubic inches like a smaller plenum (stock) or miniram type.
and besides I have an airfoil, I guess that test busts that myth that airfoils don't do diddly...
what would be the symtoms if the TB was too small? inability to rev?
that's not a problem with my car, plausibly the huge plenum with the SR, is a big hopper and does not run out of air molecules as soon as someting with fewer cubic inches like a smaller plenum (stock) or miniram type.
Symtoms are reaching a lower power level than possible. For your motor, having a larger than stock TB will provide a bit more power. I'd guess in the 10hp range. Your SR plenum won't keep it from running out of air.
Make sure you have a descreened MAF or larger MAF housing. If you're running a stock MAF, that's a bigger problem.
Remember the weakest link in a chain will limit your power.
Safety Car
Joined: Sep 2001
Posts: 4,157
Likes: 554
From: Glenbeulah Wi
No I was under the impression the 48 flowed 850, hence my not needing to spend more money
and besides I have an airfoil, I guess that test busts that myth that airfoils don't do diddly...
what would be the symtoms if the TB was too small? inability to rev?
that's not a problem with my car, plausibly the huge plenum with the SR, is a big hopper and does not run out of air molecules as soon as someting with fewer cubic inches like a smaller plenum (stock) or miniram type.
and besides I have an airfoil, I guess that test busts that myth that airfoils don't do diddly...
what would be the symtoms if the TB was too small? inability to rev?
that's not a problem with my car, plausibly the huge plenum with the SR, is a big hopper and does not run out of air molecules as soon as someting with fewer cubic inches like a smaller plenum (stock) or miniram type.
Drifting
Joined: Oct 2006
Posts: 1,934
Likes: 3
From: Citrus Heights California
Stock pressure may be a bit less (according to FIC). I've heard numbers as low as 39-40psi. So, plan accordingly. Your tuner's comment about dialing in any combo should be qualified. When I asked Jon about using larger injectors, I asked about min and max pressure. There was a (fairly high) minimum pressure -- especially on des 2/3 units. And, you want to stay reasonably high on DC as well. IOW, you can shorten pulse width but don't install something that forces it terribly short.
My preference is to do like you did and pick an injector on the smaller side to insure good pressure and DC (e.g., Ford 24lbs units -- that shoot ~25.6lbs in our rails). While something like 36-42lb injectors could be made to work, I'm skeptical about that being a good option.
My preference is to do like you did and pick an injector on the smaller side to insure good pressure and DC (e.g., Ford 24lbs units -- that shoot ~25.6lbs in our rails). While something like 36-42lb injectors could be made to work, I'm skeptical about that being a good option.
Race Director
Joined: Nov 2003
Posts: 12,221
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
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On behalf of people buying huge injectors, thanks for the clarification.
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
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Well, Brian, that's what I'd always heard before I found the "university" study linked (in post #48) above. Are you certain you're right and they're wrong (about their 780cfm measurement)? For example, is there at least one TPI/LTx TB that flows more? (That they might have measured.)
IOW, can you provide an guess/explanation regarding any error you see in their results?
Gregg
IOW, can you provide an guess/explanation regarding any error you see in their results?
Gregg
Safety Car
Joined: Oct 2008
Posts: 4,022
Likes: 30
From: Los Angeles CA
Air foils don't do diddly for a car that's sufficiently fed with a stock TB. But, they will improve flow. Stockers motors don't need extra TB flow. Also, as I posted in another thread, get rid of your plastic TB. It could easily ruin your motor. What do you think the results will be -- if it breaks off and gets sucked in?
Symtoms are reaching a lower power level than possible. For your motor, having a larger than stock TB will provide a bit more power. I'd guess in the 10hp range. Your SR plenum won't keep it from running out of air.
Make sure you have a descreened MAF or larger MAF housing. If you're running a stock MAF, that's a bigger problem.
Remember the weakest link in a chain will limit your power.
Symtoms are reaching a lower power level than possible. For your motor, having a larger than stock TB will provide a bit more power. I'd guess in the 10hp range. Your SR plenum won't keep it from running out of air.
Make sure you have a descreened MAF or larger MAF housing. If you're running a stock MAF, that's a bigger problem.
Remember the weakest link in a chain will limit your power.
stock MAF and papaer air filter with aftermarket cutout lid....
