1985 corvette 383.
Thread Starter
Advanced
Joined: Nov 2008
Posts: 92
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From: Meridian Mississippi
1985 corvette 383.
I know you guys have probably seen this question a thousand times, but I am building a 383 for my 1985 corvette. I bought a late model block so that I can run a full roller set-up. I bought an eagle rotating assembly with flat-top pistons. I plan to use my stock TPI intake, stock throttle body, stock mass air flow sensor, stock injectors, computer and exhaust manifolds for now. (corvettes are expensive). I do have an adjustable fuel pressure regulator from T.P.I.S., smog pump delete kit, spec clutch, I bought a set of heads with 2.02 in and 1.60 ex valves that have been ported and polished.
1) I need help with what size cam I should run.
2) What I should buy next
3) What I shouldn't waste my money on.
and finally
4) Will this even work?
I'm not new to engine building but I am new to fuel injection so any suggestions at all for anything fuel injection related will help.
Thanks
1) I need help with what size cam I should run.
2) What I should buy next
3) What I shouldn't waste my money on.
and finally
4) Will this even work?
I'm not new to engine building but I am new to fuel injection so any suggestions at all for anything fuel injection related will help.
Thanks
Pro
Joined: Jan 2004
Posts: 503
Likes: 0
From: Forney Texas
You really don't want to use the L98 intake setup. Remember it was designed for a 305, limits a 350 to around 4800 rpm due to lack of airflow and will not allow your 383 to perform like you are thinking it will. My experience has been to hold off, gather the correct parts and then build your setup. Parts that are matched to work together will give you optimum performance and will be less likely to disappoint.
As far as your cam goes, you can give Comp Cams a call. Have all of your specs at hand and be able to give them your vision for the engine's performance and they should be able to help you out.
90Indy
As far as your cam goes, you can give Comp Cams a call. Have all of your specs at hand and be able to give them your vision for the engine's performance and they should be able to help you out.
90Indy
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
If you insist on using the TPI on a 383, which will be like an elephant breathing under water with a straw, then I'd choose an Accel 211 or 219 camshaft.
Preferably the 219, because it will respond to mods you do on the intake and exhaust later.
85 must have new heads, what is the intake port size on what youre going with?
Your stock injectors are adequate for now, but 1.6RR will be needed and a custom chip will be warranted after the cam change.
Preferably the 219, because it will respond to mods you do on the intake and exhaust later.
85 must have new heads, what is the intake port size on what youre going with?
Your stock injectors are adequate for now, but 1.6RR will be needed and a custom chip will be warranted after the cam change.
Thread Starter
Advanced
Joined: Nov 2008
Posts: 92
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From: Meridian Mississippi
I dont know what the port size is. I bought the heads from a friend of mine and he just said that they had been ported and polished. From the look of them they havent been ported much. Will the late model block bolt up to my trans? I have the 4+3 manual trans. What kind of intake do you reccomend and where can I get one?
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Well if you can get a casting # or something off the heads, someone would be able to find some info on the stock version, and we can guesstimate after the P&P. So please do that first.
I am one of (seemingly fewer) the proponents of the SuperRam intake, particularly on 383s with A4s. I think its also a good fit for the 4+3, but having the manual puts the miniram/LT1 intake on the table. The question is where you want your power, whether you want a street torque machine, etc. I elaborate on that point on my site if you want to read it.
Basically you can pick either you want, but that will dictate parts of your plan. E.g., 219 is built for the SR, and will work just great with MR, but with MR there are different cam choices that might make more peak HP (hotcam, cc306, etc.) and provide different powerband characteristics.
It will bolt to your tranny just fine, I dont see why there would be a problem.
PCMforless does the chips, and there are others, but do not buy a generic "Stage X" chip from one of these suppliers, get a custom chip tuned specifically for your mods.
I am one of (seemingly fewer) the proponents of the SuperRam intake, particularly on 383s with A4s. I think its also a good fit for the 4+3, but having the manual puts the miniram/LT1 intake on the table. The question is where you want your power, whether you want a street torque machine, etc. I elaborate on that point on my site if you want to read it.
Basically you can pick either you want, but that will dictate parts of your plan. E.g., 219 is built for the SR, and will work just great with MR, but with MR there are different cam choices that might make more peak HP (hotcam, cc306, etc.) and provide different powerband characteristics.
It will bolt to your tranny just fine, I dont see why there would be a problem.
PCMforless does the chips, and there are others, but do not buy a generic "Stage X" chip from one of these suppliers, get a custom chip tuned specifically for your mods.
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
Well if you can get a casting # or something off the heads, someone would be able to find some info on the stock version, and we can guesstimate after the P&P. So please do that first.
I am one of (seemingly fewer) the proponents of the SuperRam intake, particularly on 383s with A4s. I think its also a good fit for the 4+3, but having the manual puts the miniram/LT1 intake on the table. The question is where you want your power, whether you want a street torque machine, etc. I elaborate on that point on my site if you want to read it.
Basically you can pick either you want, but that will dictate parts of your plan. E.g., 219 is built for the SR, and will work just great with MR, but with MR there are different cam choices that might make more peak HP (hotcam, cc306, etc.) and provide different powerband characteristics.
It will bolt to your tranny just fine, I dont see why there would be a problem.
PCMforless does the chips, and there are others, but do not buy a generic "Stage X" chip from one of these suppliers, get a custom chip tuned specifically for your mods.
I am one of (seemingly fewer) the proponents of the SuperRam intake, particularly on 383s with A4s. I think its also a good fit for the 4+3, but having the manual puts the miniram/LT1 intake on the table. The question is where you want your power, whether you want a street torque machine, etc. I elaborate on that point on my site if you want to read it.
Basically you can pick either you want, but that will dictate parts of your plan. E.g., 219 is built for the SR, and will work just great with MR, but with MR there are different cam choices that might make more peak HP (hotcam, cc306, etc.) and provide different powerband characteristics.
It will bolt to your tranny just fine, I dont see why there would be a problem.
PCMforless does the chips, and there are others, but do not buy a generic "Stage X" chip from one of these suppliers, get a custom chip tuned specifically for your mods.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Block will bolt up,
you need a new flywheel because the late 1 pce seal crank (roller engine ) has a different flange bolt pattern to your 2 pce seal '85 crank.
3.00" v 3.58" PCD
Factory late 4+3 Vette flywheel was GM # 14088646
You need to have your engine balanced with this flywheel as factory balance setup is different
1 v 2 pce seal engines.
you need a new flywheel because the late 1 pce seal crank (roller engine ) has a different flange bolt pattern to your 2 pce seal '85 crank.
3.00" v 3.58" PCD
Factory late 4+3 Vette flywheel was GM # 14088646
You need to have your engine balanced with this flywheel as factory balance setup is different
1 v 2 pce seal engines.
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Melting Slicks
Joined: Jan 2008
Posts: 2,054
Likes: 120
From: AZ
Won't those limit the power, unless he cranks up the fuel pressure? I know some tuners like that approach, but others prefer a stock FP. I wasted the $$ on a FPR as I run stock FP and my custom chip is designed for it.
I love the flat power curve of the SR, even if it is a PITA to work with on my 409.
Your 4+3 may have a lot of wear inside, depending on the mileage and how it was treated. In mine, second gear was worn through the case hardening and virtually all the gears had many micro cracks.. a disaster waiting to happen with the extra power.... Similar to the broken gears in my original D36 from all that torque.
I love the flat power curve of the SR, even if it is a PITA to work with on my 409.
Your 4+3 may have a lot of wear inside, depending on the mileage and how it was treated. In mine, second gear was worn through the case hardening and virtually all the gears had many micro cracks.. a disaster waiting to happen with the extra power.... Similar to the broken gears in my original D36 from all that torque.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia