383 stroker fuel problem help!
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Intermediate
Joined: Jun 2011
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383 stroker fuel problem help!
Hey guys. My mechanic just got my 383 stroker installed into my 1987 corvette. It is a mild 383 with a roller cam, ported iron heads etc. The intake i am running is an edlebrock tpi high flow intake with the stock everything else as far as tpi goes. Here is the problem. We cannot figure out why it is over loading on fuel, otherwise known as running rich. The fuel pressure and compression checked out good. Here is my thought, could it be that the stock tpi system is starving the engine of much needed air induction? i have the new edlebrock high flow intake, but like i said everything else is bone stock and i know those tpis were built for 305 in reality. Anyway, could it be starving the engine of air, therefore making the engine load up on gas? What are you guys's professional opinions? Should i buy a new throttle body and runners as well as injectors, fuel rail etc? whats your imput?
Melting Slicks
Joined: Jun 2010
Posts: 2,178
Likes: 1
You need to have the chip re tuned for your engine. Its getting way more air than factory and the engine management system is trying to compensate.
www.pcmforless.com , 100-150 bucks and you are good to go.
Also, what is your camshaft specs, injector size, exhaust (headers, factory, etc). SO many things. But basically your engine needs more fuel and air to handle the 33 more cubic inches of inches, let alone your larger better flowing heads.
www.pcmforless.com , 100-150 bucks and you are good to go.
Also, what is your camshaft specs, injector size, exhaust (headers, factory, etc). SO many things. But basically your engine needs more fuel and air to handle the 33 more cubic inches of inches, let alone your larger better flowing heads.
Last edited by Charleston2012; Sep 29, 2011 at 08:11 PM.
Thread Starter
Intermediate
Joined: Jun 2011
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[QUOTE=Charleston2012;1578833753]You need to have the chip re tuned for your engine. Its getting way more air than factory and the engine management system is trying to compensate.
www.pcmforless.com , 100-150 bucks and you are good to go.
Also, what is your camshaft specs, injector size, exhaust (headers, factory, etc). SO many things. But basically your engine needs more fuel and air to handle the 33 more cubic inches of inches, let alone your larger better flowing heads.[/QUOTE
Im totally spaced out on the camshaft size, i know it isnt big enough to need a stall converter, but i ll ask the mechanic tmmrw. and the injectors are the stock and i have a high flow exhaust system from the cat back and that comes from exhaust manifolds which are stock. U think thats why its overloading on fuel? The chip?
www.pcmforless.com , 100-150 bucks and you are good to go.
Also, what is your camshaft specs, injector size, exhaust (headers, factory, etc). SO many things. But basically your engine needs more fuel and air to handle the 33 more cubic inches of inches, let alone your larger better flowing heads.[/QUOTE
Im totally spaced out on the camshaft size, i know it isnt big enough to need a stall converter, but i ll ask the mechanic tmmrw. and the injectors are the stock and i have a high flow exhaust system from the cat back and that comes from exhaust manifolds which are stock. U think thats why its overloading on fuel? The chip?
Melting Slicks
Joined: Jun 2010
Posts: 2,178
Likes: 1
[QUOTE=raw vette;1578833992]
. Yes, the retune will fix the loading/richness.
You need to get specifics on cam, and any other modifications to your engine.
Call pcmforless and work witb them. You will fix your fueling issue. Then, you may need larger injectors, as your 21#s are probably too small for a 383.
You need to have the chip re tuned for your engine. Its getting way more air than factory and the engine management system is trying to compensate.
www.pcmforless.com , 100-150 bucks and you are good to go.
Also, what is your camshaft specs, injector size, exhaust (headers, factory, etc). SO many things. But basically your engine needs more fuel and air to handle the 33 more cubic inches of inches, let alone your larger better flowing heads.[/QUOTE
Im totally spaced out on the camshaft size, i know it isnt big enough to need a stall converter, but i ll ask the mechanic tmmrw. and the injectors are the stock and i have a high flow exhaust system from the cat back and that comes from exhaust manifolds which are stock. U think thats why its overloading on fuel? The chip?
www.pcmforless.com , 100-150 bucks and you are good to go.
Also, what is your camshaft specs, injector size, exhaust (headers, factory, etc). SO many things. But basically your engine needs more fuel and air to handle the 33 more cubic inches of inches, let alone your larger better flowing heads.[/QUOTE
Im totally spaced out on the camshaft size, i know it isnt big enough to need a stall converter, but i ll ask the mechanic tmmrw. and the injectors are the stock and i have a high flow exhaust system from the cat back and that comes from exhaust manifolds which are stock. U think thats why its overloading on fuel? The chip?
You need to get specifics on cam, and any other modifications to your engine.
Call pcmforless and work witb them. You will fix your fueling issue. Then, you may need larger injectors, as your 21#s are probably too small for a 383.
Thread Starter
Intermediate
Joined: Jun 2011
Posts: 32
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[QUOTE=Charleston2012;1578836351]
So i actually got to start it today. Sounded pretty rough at idle but strong at high revs. Of course only had it running like a minute so i didnt mess anything up internally. This engine is brand new.lol. It blew the black smoke..all sensors and injectors have been checked. So u think the computer needs tuned? if so..im just gonna pick it up from the shop monday..and send it in myself and install it myself. Im so pumped to drive this thing
. Yes, the retune will fix the loading/richness.
You need to get specifics on cam, and any other modifications to your engine.
Call pcmforless and work witb them. You will fix your fueling issue. Then, you may need larger injectors, as your 21#s are probably too small for a 383.
You need to get specifics on cam, and any other modifications to your engine.
Call pcmforless and work witb them. You will fix your fueling issue. Then, you may need larger injectors, as your 21#s are probably too small for a 383.
Melting Slicks
Joined: Jun 2010
Posts: 2,178
Likes: 1
Yes, get it tuned to at least have it, the ecm, working with all the knew components etc. PCMFORLESS will get you going in the right direction.. One side running rich can be attributed to poorly tuned ecm.
Get new plugs for the car before you run the new tune also.
Get new plugs for the car before you run the new tune also.
Burning Brakes
Joined: Feb 2010
Posts: 1,013
Likes: 2
From: California City Ca
My 383 ran but very poorly while I waiting for my new Chip from PCMforless showed up it made a world of difference.
Even I ram unning a LT4 hotcam it Idle smooth I waited a more noticeable idle but I live with it.
Even I ram unning a LT4 hotcam it Idle smooth I waited a more noticeable idle but I live with it.
Last edited by Marv02; Oct 2, 2011 at 09:20 AM.
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Team Owner
Joined: Oct 2004
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From: altered state
St. Jude Donor '05
If its rich enough to blow black smoke DO NOT DRIVE IT!
No starting nothing.
Get a tune and the right injectors.
Dont wanna glaze those cylinder walls, takes less than one would think.
No starting nothing.
Get a tune and the right injectors.
Dont wanna glaze those cylinder walls, takes less than one would think.
Burning Brakes
Joined: Feb 2010
Posts: 1,013
Likes: 2
From: California City Ca
2nd that.
If I was you before get a new chip get all the right part so you dont have to get anouther chip burned for that latter on down the road.
I running 24# injectors and what I read they are on the small size for a 383 but once agin my motor not going to see 5500 RPM's once in a blue moon it see 5000 RPM's, if it lucky.
It's a DD street car with some extra kick built into it just for the fun of it.
If I was you before get a new chip get all the right part so you dont have to get anouther chip burned for that latter on down the road.
I running 24# injectors and what I read they are on the small size for a 383 but once agin my motor not going to see 5500 RPM's once in a blue moon it see 5000 RPM's, if it lucky.
It's a DD street car with some extra kick built into it just for the fun of it.
Last edited by Marv02; Oct 1, 2011 at 06:13 PM.
Thread Starter
Intermediate
Joined: Jun 2011
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so here is my plan. Buy new bigger injectors, a 58 mm throttle body, and then go have the computer tuned to the engine. if later on down the road i wanted to put on high flow runners..would I have to re tune it? or should i do runners instead of the new throttle body? what do u guys think?
Burning Brakes
Joined: Feb 2010
Posts: 1,013
Likes: 2
From: California City Ca
What I read and told unles you have mega HP and a motor that turns sky high RPM's you dont need any thing more than the stock TB.
I would get a set of 30# Injectors First get the chip.
For me I already had my 24# injectors from my 355 motor i just reused them.
I have SPL runners on mine the price is good and they say you dont have to get the chip reburnt for just the runners same for the intake But you alway get the chip burnt for it then down the road get the runners.
Are you going to run headers Cat mufflers ect let the tunner know what you going to run if you run full lenght headers use a heated O2 senser trust me on this one you will not get to idel right.
Plan ahead will save your self alot headachs in the long run even you do plan ahead Murphies law will still reach up and bit you LOL.
Mr Murphy knows me very well.
QUOTE=raw vette;1578849235]so here is my plan. Buy new bigger injectors, a 58 mm throttle body, and then go have the computer tuned to the engine. if later on down the road i wanted to put on high flow runners..would I have to re tune it? or should i do runners instead of the new throttle body? what do u guys think?[/QUOTE]
I would get a set of 30# Injectors First get the chip.
For me I already had my 24# injectors from my 355 motor i just reused them.
I have SPL runners on mine the price is good and they say you dont have to get the chip reburnt for just the runners same for the intake But you alway get the chip burnt for it then down the road get the runners.
Are you going to run headers Cat mufflers ect let the tunner know what you going to run if you run full lenght headers use a heated O2 senser trust me on this one you will not get to idel right.
Plan ahead will save your self alot headachs in the long run even you do plan ahead Murphies law will still reach up and bit you LOL.
Mr Murphy knows me very well.
QUOTE=raw vette;1578849235]so here is my plan. Buy new bigger injectors, a 58 mm throttle body, and then go have the computer tuned to the engine. if later on down the road i wanted to put on high flow runners..would I have to re tune it? or should i do runners instead of the new throttle body? what do u guys think?[/QUOTE]
Last edited by Marv02; Oct 2, 2011 at 09:22 AM.
Thread Starter
Intermediate
Joined: Jun 2011
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[QUOTE=Charleston2012;1578849315]RUNNERS and port the base.....[/QUOTu
well since i have the eldelbrock high flow intake, i might as well put the high flow runners on from edelbrock, and the 30 lb injectors and then get it tuned.
and i am running stock exhaust manifolds, but the catback exhaust system is aftermarket.
well since i have the eldelbrock high flow intake, i might as well put the high flow runners on from edelbrock, and the 30 lb injectors and then get it tuned.
and i am running stock exhaust manifolds, but the catback exhaust system is aftermarket.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
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From: WV
30# injectors are overkill if your going to run TPI intake..If your running a Super ram 30# injectors are ok , but not for TPI.. Jon at FIC told me the 24# injectors are what I needed for my 383 up to about 375 hp and your motor will have no more HP then that, our motors are very close to the same build . Im running an Edelbrook base, Accel high flow runners and a Mega ported plenum, all ported and port matched. Im also running Hooker LT headers with air and egr delete...I would suggest calling Jon to verify what Im telling you, he will sell you the right injectors...WW
Last edited by WW7; Oct 2, 2011 at 09:08 AM.
Burning Brakes
Joined: Feb 2010
Posts: 1,013
Likes: 2
From: California City Ca
Jon from FIC told me my 24 will work but 30 would been better I also running full lenght headers, Eldelbrock high flow intake, SLP runners I think the slp were a bit cheeper and I just like the looks of them better my self.
30# injectors are overkill if your going to run TPI intake..If your running a Super ram 30# injectors are ok , but not for TPI.. Jon at FIC told me the 24# injectors are what I needed for my 383 up to about 375 hp and your motor will have no more HP then that, our motors are very close to the same build . Im running an Edelbrook base, Accel high flow runners and a Mega ported plenum, all ported and port matched. Im also running Hooker LT headers with air and egr delete...I would suggest calling Jon to verify what Im telling you, he will sell you the right injectors...WW
Drifting
Joined: Apr 2007
Posts: 1,339
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From: port charlotte fl
30# injectors are overkill if your going to run TPI intake..If your running a Super ram 30# injectors are ok , but not for TPI.. Jon at FIC told me the 24# injectors are what I needed for my 383 up to about 375 hp and your motor will have no more HP then that, our motors are very close to the same build . Im running an Edelbrook base, Accel high flow runners and a Mega ported plenum, all ported and port matched. Im also running Hooker LT headers with air and egr delete...I would suggest calling Jon to verify what Im telling you, he will sell you the right injectors...WW
Mines about as good as it gets and runs#24 injectors. Superam fitted and pulls strong through 6000. You don't need bigger. Incidentally,you say yours is an '87.Why don't you have aluminum heads instead of cast iron?
Le Mans Master
Joined: Sep 2006
Posts: 6,050
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From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
If you are starting a cold, over rich, brand new engine and revving it high enough to say it runs good at high revs, just plan on consuming oil.
Engines that are new need to be driven briskly, but not revved with no load.
If your fuel metering system, is rich enough to blow black smoke, it's rich enough to wash off all the lubricating oil off of the rings on deceleration.
Normal deceleration processes in the computer lean out the mixture, but if the air measuring tables are off, it can't do that. Get that chip reprogrammed.
Engines that are new need to be driven briskly, but not revved with no load.
If your fuel metering system, is rich enough to blow black smoke, it's rich enough to wash off all the lubricating oil off of the rings on deceleration.
Normal deceleration processes in the computer lean out the mixture, but if the air measuring tables are off, it can't do that. Get that chip reprogrammed.
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Intermediate
Joined: Jun 2011
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my previous engine in the car had the stock aluminum heads but became severely damaged by the last owner. he lived in miami and put water in the radiator..came up to kansas and cracked the engine block during the winter, incidentally the heads also got warped and the company that built the new engine for me put on the ported cast iron heads, but the company also guarenteed an easy engine swap, we had to change size of harmonic balancer, oil pan, and now computer because they put to strong of a cam in. We SPECIFICALLY told them to match the engine up for a 87 corvette, and make it so we didnt have to mess with the computer. but since its a 383, i guess there has to be tuning, especially since its 33 more cubes and has a high lifted cam. ima go with the #24 injectors, and eldbrock fast flow runners and then hopefully the tune fixes the problem. My mechanic has been through the entire engine three times, so this must fix the problem.