VetteSteve

Hello, I was wondering what would be the best carb for the money to put on a (freshly rebuilt) orig. 76 L82 engine. The current carb on the engine is a weak 2 barrel carb with a small air filter on top. I feel that the engine is loosing HP with this current set up.

The engine has just been rebuilt and restored to factory specs with few changes. With a budget of about $300-400 dollars what would be the best carb & air filter to add to this eager engine? Or if you could tell me what works best for you and the cost that would be awesome.
Thanks,
Steve :hat



[Modified by VetteSteve, 9:36 PM 1/4/2003]

Larry B.

The original engine was a Quadra-jet 4 barrel. Corvettes never came with 2 barrel carbs. If you have anything else then it is not original. If you have a q-jet manifold, the best carb and easiest to install in my opinion would be an Edelbrock Q-jet replacement (new). ANY over the counter Rebuilt Q-jet is a complete waste of time any money. If you have the original Q-jet, there are a few people that can rebuild it. Other forum members may be more help.

page62

:iagree: But you can save 100+ bucks and get an almost-new remanufactured Edelbrock QJet from Summit Racing (that's what I have and it's great) :yesnod:

VetteSteve

Im an idiot, I have the Rochester Quadrajet 4 barrel is the stock orig. carb. But is there anything better with more options?
Steve :D


[Modified by VetteSteve, 10:31 PM 1/4/2003]

Smokehouse69

A well tuned and setup Q-jet will perform as good as any carb out there (at least that's what the Big Boys tell me) :D

page62

Your carb may be OK for now -- perhaps a little tuning is in order -- but what sort of exhaust system do you have?

Let's find the most efficient way to spend that money! :yesnod:

Larry B.

That's more like it.... First make sure that the gas pedal actually opens the carb all the way against the stop on the left (driver's ) side of the carb.If that isn't happening, check the pedal bracket under the dash. They are known to bend over the years. This is a common thing with early C-3's. Just straighten it so the carb goes all the way open. IF that is OK then make sure the choke is completely open when the engine is warm. There is a link that won't allow the secondaries to open while the choke is on. ( Another common thing ) Then.... IF the engine is all stock, you just may be expecting too much from it. The stock engines in the mid 70's were very low performance smog motors. Mid seventies corvettes (and other cars of that era) were not known to be fast in stock form.

VetteSteve

My exhaust is stock as well. ( Nothing has ever been done to it to my knowlage) I looked at the carb and it opens up all the way, nothing bent. Hmmm maybe i do want too much performance from my engine. If you had 400 bucks to spend. How would you spend it if you were me. And im looking for speed! :hat

AlwaysWave

Dollar for dollar, I'm a big proponent for the Edelbrock square bores. I really like my #1406. Easy to get tuned in and no problems.

page62

What you want is custom dual exhaust. And in San Antonio we're blessed to have about 101 different shops that can do it cheap & quick! Tell 'em you want 2½" true duals, with an "H" pipe (also called a balance pipe).

Larry B.

Another thing to check is the distributor advance mechanism. The inner shaft must move independent and very free. It should move a few degrees and snap back with the springs. Those tend to sieze over time. An engine operating without the proper advance curve will run fine but just have no throttle response.

redwingvette

If the engine is rebuilt than you may want to stick a better cam in it before you need to worry about other upgrades. The next thing would be the exhaust system. The carb is as good as they come for your application if it is working right. The cam is the heart and soul of your engine and needs to be matched with the rest of the drive train. The smog motors and rear gear were made to have good "gas milage" and not performance. Recurving the distributor is a good way to improve low end performance for very little cost. See the tech page for how to do the job. I am not sure what can be done with the HEI systems. Depending on thwe shape of your motor will determine where you should spend your money.

Pete76Shark

What is the benefit of an H pipe on a true duals system ?
I have a 76 and have been watching this tread and I am considering changing my stock exhaust to a true duals.

VetteSteve, consider getting the Lars recurve kit. You get new distributor springs and weights, this will allow all of the mechanical advance to come in early and you will notice a difference in power.

Pete

Smokehouse69

Get yourself a set of Dynomax Ceramic coated headers and a new dual exhaust system. Jeg's or Summit Racing has them for around $219.00, for another 250 you should be able to find one of the multitude of muffler shops in S.A. to put you a set of true dual exhaust, with a crossover.
A little over your $400.00 budget, but the biggest performance boost for your money is a set of headers.

page62

An H-pipe does two things: it improves low-end torque, and smooths out the exhaust note at low rpm.

My car came with a true dual system but no H-pipe. I went to one of San Antonio's many muffler shops (se habla Espanol) and had them put one in for $30 -- the difference was immediately noticeable!

redwingvette

A H-pipe also reduces exhaust pressure in smaller exhaust pipe systems by allowing the use of both mufflers. Exhaust is coming out in pulses causing a vacuum from one side to the other. The H-pipe creates a smooth flow of exhaust, which helps to balance the system.

gdh

If you want to cut $ you could buy a set of Hedman Headers for less than 50% of the deramic coated Dynomax, then you would be closer to your budget with addition of 2.5" true duals, an H or X pipe and a set of high flowing mufflers. There are a lot of prior threads that you can do a search on as to which and how much for mufflers. Get your carb tuned by an expert (Lars for instance). But I think your exhaust system needs attention first.

VetteSteve

Looks like the general consensus is to follow this path of upgrades. :cheers:

1~ Tune the original 4 barrel carb, distributor advance mechanism and gas petal lines to carburetor.

2~ Put a better cam in it. ( any ideas for specific kind? )

3~ Buy a set of Hedman Headers for less than 50% of the deramic coated Dynomax

3~ Upgrade to custom dual exhaust. ( 2½" true duals, with an "H" pipe ) cost $30 at local muffler shop

Looks like a good plan to me... Is there anything else I would need for the exhaust system? For example ... maybe some Borla mufflers?
:hat

Ryan77

I think he said the H pipe alone was $30, I doubt you'll be able to get true duals put in for $30 :eek:, I wish you could though :D . For this application something like the Comp Cams 256XE would be a good a cam, although I don't know the specs of the stock L-82 cam, so it might not be too much of an improvement, and you could go for something bigger like the 262XE instead.




[Modified by Ryan77, 2:25 PM 1/5/2003]

page62

:iagree: But it's not going to cost a fortune either. Let's just say that whever he goes, Spanish will be spoken ... and maybe 1 or 2 people in the shop will speak English. How well do you know San Antonio, Steve?