L 83 performance
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The guys who haven't died while waiting to get their hands on one report good results.
http://forums.corvetteforum.com/1575335208-post29.html
The new intake changes the whole dynamics of the CFI so you would ultimately want to get rid altogether of the marginal stock L83 heads and cam to get the best out of the intake swap
http://forums.corvetteforum.com/1575335208-post29.html
The new intake changes the whole dynamics of the CFI so you would ultimately want to get rid altogether of the marginal stock L83 heads and cam to get the best out of the intake swap
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,460
Likes: 48
The guys who haven't died while waiting to get their hands on one report good results.
http://forums.corvetteforum.com/1575335208-post29.html
The new intake changes the whole dynamics of the CFI so you would ultimately want to get rid altogether of the marginal stock L83 heads and cam to get the best out of the intake swap
http://forums.corvetteforum.com/1575335208-post29.html
The new intake changes the whole dynamics of the CFI so you would ultimately want to get rid altogether of the marginal stock L83 heads and cam to get the best out of the intake swap
thank you
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,460
Likes: 48
Safety Car
Joined: Jan 2004
Posts: 3,556
Likes: 13
IIRC only a reg head version is being made
Google Chevy 462624 head
Can't find a direct link at present but this cut n paste from a CFI guru is typical of what you will find if you search L83/CFI.
"don't jump into ANY project without thinking thru your options and thinking thru your goals, if you want a mild increase in hp a simple cam swap
and a low restriction exhaust and headers will work fine.
if you want a more extensive upgrade it requires thinking thru your goals and selecting components that allow you to reach those goals,
at some point the stock components will be a huge restriction to further progress..... to sum it up, the stock heads SUCK,
in that those heads flow less than 200cfm in stock form, the stock cams restricting power to the 1000rpm-4500rpm power band,
and the x-fire intakes a total restrictive disaster, yes it can be improved, but not enough to make the work worth the results,
in my opinion.
Add to that the restrictive stock exhaust and your beating a dead horse,you can of course do that but after working on at least a
dozen cross fire projects and seeing the results of beating that dead horse vs swapping to other components its a total
no brainer in my opinion to upgrade the intake, heads and cam and exhaust, rather than be saddled with the
restrictive components, limitations."
Google Chevy 462624 head
Can't find a direct link at present but this cut n paste from a CFI guru is typical of what you will find if you search L83/CFI.
"don't jump into ANY project without thinking thru your options and thinking thru your goals, if you want a mild increase in hp a simple cam swap
and a low restriction exhaust and headers will work fine.
if you want a more extensive upgrade it requires thinking thru your goals and selecting components that allow you to reach those goals,
at some point the stock components will be a huge restriction to further progress..... to sum it up, the stock heads SUCK,
in that those heads flow less than 200cfm in stock form, the stock cams restricting power to the 1000rpm-4500rpm power band,
and the x-fire intakes a total restrictive disaster, yes it can be improved, but not enough to make the work worth the results,
in my opinion.
Add to that the restrictive stock exhaust and your beating a dead horse,you can of course do that but after working on at least a
dozen cross fire projects and seeing the results of beating that dead horse vs swapping to other components its a total
no brainer in my opinion to upgrade the intake, heads and cam and exhaust, rather than be saddled with the
restrictive components, limitations."
Last edited by vetteoz; Aug 15, 2013 at 12:38 AM.
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,460
Likes: 48
So I am a little confused. The renegade manifold only works with the stock heads, correct?
The vorterc heads can increase my HP by ?
The vortec heads do not work with the CFI manifold?
If I were to put on the vortec heads I would then have to change to a single TBI manifold?
Can I run the stock cam with the vortec heads?
My goal would not be running the car over 4500 rpm. I would like a little more acceleration for passing and road driving, not a quarter mile acceleration run. I want to keep a nice stock idle and driveable car.
Thanks for the help
The vorterc heads can increase my HP by ?
The vortec heads do not work with the CFI manifold?
If I were to put on the vortec heads I would then have to change to a single TBI manifold?
Can I run the stock cam with the vortec heads?
My goal would not be running the car over 4500 rpm. I would like a little more acceleration for passing and road driving, not a quarter mile acceleration run. I want to keep a nice stock idle and driveable car.
Thanks for the help
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Joined: Jan 2004
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the manifold does not work with Vortec heads.
You can use ANY std (better than yours ) SBC head you wish to install
http://www.summitracing.com/parts/su...make/chevrolet
You could but most would probably change it to get the best out of better heads.
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,460
Likes: 48
No
the manifold does not work with Vortec heads.
You can use ANY std (better than yours ) SBC head you wish to install
Correct Most likely use a carb intake
http://www.summitracing.com/parts/su...make/chevrolet
You could but most would probably change it to get the best out of better heads.
the manifold does not work with Vortec heads.
You can use ANY std (better than yours ) SBC head you wish to install
Correct Most likely use a carb intake
http://www.summitracing.com/parts/su...make/chevrolet
You could but most would probably change it to get the best out of better heads.
Do other heads have EGR cross overs?
What is wrong with the stock heads?
Can they be milled down?
Ported?
Bigger valves?
and then run as good as other heads?
Just thinking out loud.
Thank you
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Safety Car
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Did you do as I suggested and research about them?????
A lackluster, low performance smog head ,prone to cracking with massive chambers that most suggest are better suited to use on a boat ;
and not on it's engine either.
http://67-72chevytrucks.com/vboard/s...ad.php?t=34583
http://www.elcaminocentral.com/showp...0&postcount=14
Yes you " could " spend large sums of money on them trying to make them better but most would say why bother when you can buy some other factory SBC head that is far better straight out of the junkyard.
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,460
Likes: 48
Did you do as I suggested and research about them?????
A lackluster, low performance smog head ,prone to cracking with massive chambers that most suggest are better suited to use on a boat ;
and not on it's engine either.
http://67-72chevytrucks.com/vboard/s...ad.php?t=34583
http://www.elcaminocentral.com/showp...0&postcount=14
Yes you " could " spend large sums of money on them trying to make them better but most would say why bother when you can buy some other factory SBC head that is far better straight out of the junkyard.
Are there any sBC heads that are a direct swap in that the CFI manifold will bolt up to it. Or do all of the options require going to a four barrel carb. I am really trying to keep it as stock as possible.
Le Mans Master
Joined: Nov 2009
Posts: 6,882
Likes: 234
From: Bangkok, Thailand
The Vortec heads would work HOWEVER, you would need to have them re-drilled (or do it yourself) for the standard bolt pattern to match your stock/Renegade intake. The Renegade has enough material to cover the taller Vortec ports.
Also, the Vortec's don't have an EGR crossover port so you would either need to eliminate the EGR system completely and recalibrate the computer for that change, or convert to an L-98 style EGR feed off the passenger side exhaust manifold. I looked into doing this when I had my 84 and put my Renegade on. You could probably do that pretty easily by converting to a set of L-98 stock headers - even though they suck for flow they are at least equal if not better than the stock L-83 stuff. That would give you the riser off the #8 runner to feed the ERG. You woul need to fabricate a tube to go from that riser to the side of the EGR pad on the Renegade. There is enough meat in the casting to drill and tap it.
The Vortec heads are cheap ($600 a pair from Summit) and make a nice power improvement (~30 hp) and the whole setup would benfit even more from a mild cam.
Also, the Vortec's don't have an EGR crossover port so you would either need to eliminate the EGR system completely and recalibrate the computer for that change, or convert to an L-98 style EGR feed off the passenger side exhaust manifold. I looked into doing this when I had my 84 and put my Renegade on. You could probably do that pretty easily by converting to a set of L-98 stock headers - even though they suck for flow they are at least equal if not better than the stock L-83 stuff. That would give you the riser off the #8 runner to feed the ERG. You woul need to fabricate a tube to go from that riser to the side of the EGR pad on the Renegade. There is enough meat in the casting to drill and tap it.
The Vortec heads are cheap ($600 a pair from Summit) and make a nice power improvement (~30 hp) and the whole setup would benfit even more from a mild cam.
Melting Slicks
Joined: Dec 2009
Posts: 2,230
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Another option that you might consider that does away with both the cfi throttle bodies & intake is switch over to a truck style tbi throttle body & performer style intake, use a tbi to 4 bbl. carb adaptor. All the electrical connections are the same (use an 87-89 truck 350 tbi unit).
Check my profile for pictures.
Check my profile for pictures.
Team Owner
Joined: Oct 2004
Posts: 81,241
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From: altered state
St. Jude Donor '05
the 624 heads just dont move any air and are too thin to even bother porting on. They are known to crack real easy too so not worth putting money into
As said lots of aftermarket heads that will be a nice improvement that will fit just fine. Check into Summit racing tell them what you have. Just dont buy the Chinese made stuff youll be Ok. You can sneak a small cam in there to compliment the heads/intake. Gotta let the techs know NOT to go big. A 25xish type cam should work Ok. If you got the heads stripped down its not much more to get the cam out and replace the timing chain while youre there. Should run real good and give stock manners
As said lots of aftermarket heads that will be a nice improvement that will fit just fine. Check into Summit racing tell them what you have. Just dont buy the Chinese made stuff youll be Ok. You can sneak a small cam in there to compliment the heads/intake. Gotta let the techs know NOT to go big. A 25xish type cam should work Ok. If you got the heads stripped down its not much more to get the cam out and replace the timing chain while youre there. Should run real good and give stock manners
Team Owner
Joined: Aug 2004
Posts: 21,543
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From: Park City Utah
Also, the Vortec's don't have an EGR crossover port so you would either need to eliminate the EGR system completely and recalibrate the computer for that change,
The Vortec heads are cheap ($600 a pair from Summit) and make a nice power improvement (~30 hp) and the whole setup would benfit even more from a mild cam.
The Vortec heads are cheap ($600 a pair from Summit) and make a nice power improvement (~30 hp) and the whole setup would benfit even more from a mild cam.
I agree that the Cortec heads CAN work w/some custom working on your part (drilling intake or drilling taping the heads and then port matching). I also agree w/others that there are a plethora of thoer heads out there that will direct bolt on to your motor and the Renegade intake. Any head for a Small block Chevy from 1955>1986 is a direct, bolt-on replacement.
Drifting
Joined: May 2013
Posts: 1,736
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From: Reno Nevada
This is not really true. It will set an SES light everytime EGR is called for, and the tables will not function properly in the programming until the temp for it's operation is maxed at 151 C in the programming. In other words, if the computer expects to see a lean condition of exhaust gases coming through and doesn't it is not operating as it should. While however minor it may be, it is fact.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
We are talking about the L83 in this thread...not the L98. The L83 has no such system in place and the ECM has "no idea" if the EGR is working or not, when commanded to. You can disconnect, render in operational, or completely remove the EGR system on an L83 and the ECM has no clue, and will not...can not set and SES light.
Ya don't need to reprogram the ECM on an L83/CFI car with regard to EGR usage. Not necessary.
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
ACTUALLY....what you're trying to "sell" is not really true. More accurately, it's not at all true.
We are talking about the L83 in this thread...not the L98. The L83 has no such system in place and the ECM has "no idea" if the EGR is working or not, when commanded to. You can disconnect, render in operational, or completely remove the EGR system on an L83 and the ECM has no clue, and will not...can not set and SES light.
Ya don't need to reprogram the ECM on an L83/CFI car with regard to EGR usage. Not necessary.
We are talking about the L83 in this thread...not the L98. The L83 has no such system in place and the ECM has "no idea" if the EGR is working or not, when commanded to. You can disconnect, render in operational, or completely remove the EGR system on an L83 and the ECM has no clue, and will not...can not set and SES light.
Ya don't need to reprogram the ECM on an L83/CFI car with regard to EGR usage. Not necessary.
When mine was a CFI I removed the EGR when I installed the Xram, SES light never came on nor did the ECM even know it was gone
Drifting
Joined: May 2013
Posts: 1,736
Likes: 31
From: Reno Nevada
ACTUALLY....what you're trying to "sell" is not really true. More accurately, it's not at all true.
We are talking about the L83 in this thread...not the L98. The L83 has no such system in place and the ECM has "no idea" if the EGR is working or not, when commanded to. You can disconnect, render in operational, or completely remove the EGR system on an L83 and the ECM has no clue, and will not...can not set and SES light.
Ya don't need to reprogram the ECM on an L83/CFI car with regard to EGR usage. Not necessary.
We are talking about the L83 in this thread...not the L98. The L83 has no such system in place and the ECM has "no idea" if the EGR is working or not, when commanded to. You can disconnect, render in operational, or completely remove the EGR system on an L83 and the ECM has no clue, and will not...can not set and SES light.
Ya don't need to reprogram the ECM on an L83/CFI car with regard to EGR usage. Not necessary.
Thread Starter
Drifting
Joined: Feb 2013
Posts: 1,460
Likes: 48
heads
I am assuming that the L98 heads do not work on the L83 engine, correct?
So in buying a set of heads do I go older or newer than the 84.
Thank you all.
Joe
How do I post a picture in my thread.