84 Crossfire performance upgrades....
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Joined: Dec 2006
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From: Baltimore Maryland
84 Crossfire performance upgrades....
Hey there, my name is Chris. I've been on the forums here and there over the years. (Owned a C3 Corvette, multiple C5s, a C6, and now a C4) I am looking for some of the best bang for the buck performance upgrades for my 84 Corvette. Its an automatic by the way. I've tried searching for some things, but found very little information. I also have had a hard time finding vendors that carry many performance parts for the 84. I'm most likely going to go with straight pipes, and maybe 3.73 gears? Any suggestions on intake, any available nitrous kits, etc? Any help would be appreciated. Thanks!! -Chris
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Short answer: Port your intake manifold to match your heads, and reduce the length of the walls between the adjacent intake tubes in the manifold plenum. When you look into your plenum you'll see what I'm talking about.
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you can port the intake yourself, which can be done but is not easy and extremely time consuming, been down that road myself
you can buy an aftermarket intake such as http://www.eddiemotorsports.com/prod...old-msren-100/
or you can get a carbed intake and convert to a single TBI, 454 TBIs flow 670CFM which is almost as good as the dual TBIs you have now which make a combined 750CFM, which is restricted by the manifold which is only capable of flowing ~435CFM
or you can just get an aftermarket intake and stick a carb on it
you can buy an aftermarket intake such as http://www.eddiemotorsports.com/prod...old-msren-100/
or you can get a carbed intake and convert to a single TBI, 454 TBIs flow 670CFM which is almost as good as the dual TBIs you have now which make a combined 750CFM, which is restricted by the manifold which is only capable of flowing ~435CFM
or you can just get an aftermarket intake and stick a carb on it
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Yup. The intake manifold is the biggest limitation for the L83 crossfire engine. There are multiple threads and info on the internet about porting the manifold. The rest of the performance upgrades are the same as any other SBC: heads, cam, exhaust, etc.
Oh, and don't forget about tuning for the changes you make if you get wild with it. Personally, I really like the EBL Flash:
http://www.dynamicefi.com/EBL_Flash.php
Oh, and don't forget about tuning for the changes you make if you get wild with it. Personally, I really like the EBL Flash:
http://www.dynamicefi.com/EBL_Flash.php
Last edited by gwbutch; Feb 21, 2014 at 11:09 AM.
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Joined: Feb 2013
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From: norway
http://www.gmhightechperformance.com...e/viewall.html http://www.bangshift.com/forum/showt...e-SBC-Manifold http://www.oldcarmemories.com/content/view/132/1/ http://www.eddiemotorsports.com/prod...am-1982-84.htm
http://forums.corvetteforum.com/c3-g...re-intake.html http://forums.corvetteforum.com/c3-g...f-and-f-p.html http://www.crossfireinjection.net/news.htm http://www.joby.se/corvette/ http://www.corvetteactioncenter.com/...njection-mine/
Last edited by corvettenorway; Feb 21, 2014 at 11:39 AM.
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FULLY porting the runners (not just port-matching the ends), optimizing fuel & timing, exhaust and a converter will put you right into the mid 13's. Pretty fantastic gains for <$1000.00
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you can port the intake yourself, which can be done but is not easy and extremely time consuming, been down that road myself
you can buy an aftermarket intake such as http://www.eddiemotorsports.com/prod...old-msren-100/
or you can get a carbed intake and convert to a single TBI, 454 TBIs flow 670CFM which is almost as good as the dual TBIs you have now which make a combined 750CFM, which is restricted by the manifold which is only capable of flowing ~435CFM
or you can just get an aftermarket intake and stick a carb on it
you can buy an aftermarket intake such as http://www.eddiemotorsports.com/prod...old-msren-100/
or you can get a carbed intake and convert to a single TBI, 454 TBIs flow 670CFM which is almost as good as the dual TBIs you have now which make a combined 750CFM, which is restricted by the manifold which is only capable of flowing ~435CFM
or you can just get an aftermarket intake and stick a carb on it
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