Replacing Carb on the L-81 Engine

[thecone]

I need to replace the carb on my vette, Does any one have a suggestion on the best replacement? ie.. Carter,holley etc.. help My Car has some Mods done in the Engine ie.. Comp Cam, Lifters, springs, K&N Airfilter and Headers. I'd like to rebuild or replace. How much should it cost to rebuild the Quadrajet? Or would it be better getting the aftermaket Carb? Thanks to all that has given me Ideas.

 

[81 MAKO]

Re-carb

We are assuming the original Q-Jet is on there; for good gas mileage the Quad-Jet is the best when all is working right with the computer assist. However, if your after the boost and H/P not worried about highway gas mileage, I would lean towards the Holley,keeping the CFM APPLICATION of any carburator a factor for that equipped stock or modified engine. Not sure if your L-81 is stock and running on the computer currently? I really like the color of your car, seen any around...Dave

 

[chockey]

I had the same question of what to do and went to a friend who is a wizard with engines and custom cars, looked at Holley that would fit but he asked me some questions.

What am I looking for in HP addition?

Do I plan on doing more modifications to the engine?

At this time are you looking to get away from as original as it is in other areas, radio, suspension, paint or body changes.

So when it was all over kept the original Q-Jet, new gaskets, cleaning, adjustments and she runs like a top from where it was. No regrets and no speeding tickets yet but she purrs like a kitten, saved myself about$150.00

Chuck

 

[Vader]

If anyone is realistically expecting any measureable power gains from simply bolting on a different carburetor, they'll surely be sorely disappointed.

A clean and properly adjusted Rochester E4ME will deliver more fuel/air miture and at the correct power enrichment than any factory 350 (especially the under-cammed, intake-choked, dished-piston L81) will ever need. Of course, Holley and Edelbrock won't tell you that, since they make a living selling carbs and intakes. Then selling the jet kits and metering plates to get them running better. Then selling the adapter plates to allow you to install the original carb once you're done experimenting and are tired of seeing the "Check Engine" light on all the time.

Save the cash you'd spend on a carb and put it where it will actually do some good, like the heads and cam.

 

[81 Corvette]

I'm swapping on a Road Deamon in the very near future. Just ordered it along with headers, a distributor and an RPM Air Gap. My biggest reason for change was teh headers. No more O2 sensor for the computer.

 

[DDLS3]

One thing to consider when changing carbs, and especially intakes, is hood clearence. If you still have your stock hood and have no plans to change it then you need to select your carb intake combo based on hight. I don't think that the air gap intake will fit under the stock hood even with a 2-1/4" open air cleaner. Just food for thought........................

 

[81 Corvette]

what about with a drop top air cleaner.

 

[Tom73]

Your options are very limited since the L81 used a computer controled carb. If the current carb is shot, I would look at rebuilding that one, or a new factory stock type carb.

tom...

 

[81 Corvette]

choices are not limited. It all depends on what you want to do. You can do the same things with an L81 as you can with an L82 or any other SBC. It just depend on if you want to use the computer or not.

 

[John Ulrich]

I had the shafts (throttle butterflies)that were leaking on my OEM Quadrajet rebushed by a local carb shop. Cleaned it up with new gaskets etc. It runs fantastic!!!

I make the mistake years ago replacing the Quadrajet on a '70 I had. Holley had introduced their replacements for the quadrajets. I bit and found out it passed less air...ie. slower. And mileage was worse!!!!

Quadrajets are great carbs...small main holes for economy, Big secondaries for putting your foot into it!!!

Later,
JU

 

[DDLS3]

I'm not sure how much you would gain with a drop top air cleaner. the rise on an RPM manifold is about an inch higher than stock I believe. The performer intake will fit under the hood but not the RPM version.

 

[Dave L.]

I have the original carb/dist on my car and I couldn't imagine the car running any better than it does. The car runs absolutely perfect and though gas mileage doesn't concern me, I am getting about 17-18 mpg. The only changes I have made are a 2101 performer intake and dual exhaust. my 2 cents!

thanks...Dave

 

[mikejpss]

Cone- I recently bought a carb from JEGS, it was a completely rebuilt carb from Jet Performance Products. They specialise in rebuilding Rochester Q-Jets and come looking like a new one. Since my 1981 was computer controlled, and Jet does not offer an exact replacement for the computer controlled model, I had to change my distributer too, changed to a vacuum advance. The carb was cheaper thru Jegs ($359 with shipping) than it was straight from Jet Performance (go figure). You can look it up on their site @ Jetperformanceproducts.com. I am very pleased with the new carb/distr. set-up, took all the rough idle problem away, and gave it more get-up and go. Hope this helps. Mike J.

 

[Macgyver]

Sooooo.... which one is better. Should you rebuild the original carb or replace w/ Edlebrock or a Holley? Can you really expect much from an aftermarket Carb or not?

W/ mpg considered, would the aftermarket ones lower it?