1981 corvette carburetor help and opinion
Thread Starter
Instructor
Joined: Mar 2009
Posts: 190
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From: Langhorne PA
1981 corvette carburetor help and opinion
Any modifications you an do to the stock carb on a 81 Vett to bring out some more life in the car or power? Want to keep the car as original as possible. There's not muh you can do from what I understand but figured I would post up here and see if anyone recommends anything.....
Maybe change the secondaries to open all the way or different hanger and rods for the secondaries, have the primary side stock main jets but have the neddles raised all the way to the power tip, have the accle pump trimmed slightly for more pump shot, the secondary air ports enlarged, the idle jets enlarged, the idle mixture ports have enlarged and have the mc solenoid adjusted. All just ideas??? Opinions? Saw another guy on the forum who did these modifications so just posted them up as examples.
Thanks
Andrew
Maybe change the secondaries to open all the way or different hanger and rods for the secondaries, have the primary side stock main jets but have the neddles raised all the way to the power tip, have the accle pump trimmed slightly for more pump shot, the secondary air ports enlarged, the idle jets enlarged, the idle mixture ports have enlarged and have the mc solenoid adjusted. All just ideas??? Opinions? Saw another guy on the forum who did these modifications so just posted them up as examples.
Thanks
Andrew
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,112
From: Crossville TN
The design and calibration of your carb is NOT an issue with you getting more power from the engine. That carb has at least 25% more capacity left, once your stock engine is using all that it can. Your '81 carb is also the only Corvette carb to be able to regulate air/fuel ratio via electric mixture solenoid built into the carb.
For better power from your engine, you should focus more on getting it to "breathe" better (heads, cam, exhaust manifolds, dual exhausts) and leave the carb/distributor/ECM/O2 sensor system alone [assuming that it is still functional].
For better power from your engine, you should focus more on getting it to "breathe" better (heads, cam, exhaust manifolds, dual exhausts) and leave the carb/distributor/ECM/O2 sensor system alone [assuming that it is still functional].
Thread Starter
Instructor
Joined: Mar 2009
Posts: 190
Likes: 0
From: Langhorne PA
I ended up changing the cam to the 1968 350hp can with matching lifters push rods springs and valves. Also out 10.1:1 compression flat top pistons dart iron heads 180cc long tube headers and straight pipe back and advanced the timing 12 degrees. If you have any other suggestions please let me know. I don't want to change the intake or distributor or carburetor but if possible would like to modify the carb to put out more power. Also willing to work on other parts of the car and engine if you have any suggestions there. Let me know.
Thanks
Andrew
Thanks
Andrew
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,112
From: Crossville TN
Send an e-mail request to Lars Grimsrud [V8FastCars@msn.com], asking for information on how to set up the distributor system on your '81 for 'performance'. Inform him of all the stuff you have done to your engine, the tranny, differential, and tires you have.
He will likely send you a paper that instructs you how to set up the distributor, etc. so your engine will perform to its maximum potential....as it sits today.
Do what he recommends and try it out. I think you will be pleased with the FREE results.
He will likely send you a paper that instructs you how to set up the distributor, etc. so your engine will perform to its maximum potential....as it sits today.
Do what he recommends and try it out. I think you will be pleased with the FREE results.
Race Director
Joined: Jul 2004
Posts: 12,672
Likes: 329
From: Scottsdale Arizona
Send an e-mail request to Lars Grimsrud [V8FastCars@msn.com], asking for information on how to set up the distributor system on your '81 for 'performance'. Inform him of all the stuff you have done to your engine, the tranny, differential, and tires you have.
He will likely send you a paper that instructs you how to set up the distributor, etc. so your engine will perform to its maximum potential....as it sits today.
Do what he recommends and try it out. I think you will be pleased with the FREE results.
He will likely send you a paper that instructs you how to set up the distributor, etc. so your engine will perform to its maximum potential....as it sits today.
Do what he recommends and try it out. I think you will be pleased with the FREE results.
Assuming that your E4ME carb is working properly, you shouldn't have to touch it. Try tuning your distributor and replace the catalytic converter with a high flow replacement. That'll get you started in the right I direction.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Not much tuning to do to the stock dizzy either, there are no fly weights or vac advance to play with. 12* BTDC is pretty good. What intake do you have? Lots of them came with the Edlebrock 2101 which is pretty respectable. Exhaust should be high on the priority list. After that heads would be the next step. With a little care you can get that thing well up in the HP range and like posted above the carb is not the limiting factor. Lose the CAT, Air Pump if you can.
