If you have removed your computer carb setup, what did you do. I was thinking of leaving the computer connected for the distrubutor advance and transmission lockup and replacing the carb with a normal manual carb.
I have posted on another thread that I will also be replacing the cylinder heads and intake at the same time.
Any help would be greatly appreciated.

 

It was easy ... installed a Big Block 454 with two 4-barrel Holley's! No computer. Also installed TH400

 

OK, I know it's not a vette, but I replaced my 81 Firebird w/305 computer controlled carb and dist just as you are thinking of doing with a edelbrock 1406 and a jegs hei dist. Was very simple and made a world of difference, especially since the computer was going south to begin with. Would run good for about 15 minutes then tried to die (with computer). A little fine tuning on the edelbrock and it runs great. I also installed a set of hooker headers and true dual system at the same time. I did have to get an adaptor plate for the carb to go from spread bore to square bore. Fortunately I live in a place that doesn't check emisions.

by the way, thats a beautiful vette you have!

 

I dumped the entire system and went with a Comp 268H cam, Comp roller rockers, Dart Iron Eagle heads, Manley Race Flo valves, Davis DUI distributor custom curved for the cam, Davis 10mm wires, Hedman headers with 2.5 pipes and Flowmaster Delta 40 mufflers, Edelbrock Performer EPS intake, Holley 650 Avenger carb, Stewart stage 2 water pump, Dewitt aluminum radiator with Spal fans, Melling high pressure oil pump, 7 qt Moroso pan, TCI 2200rpm Saturday Night Special stall converter, Transgo shift kit and deep sump. I reused the stock pistons so the motor runs great on 87 octane. I haven't had time to dyno the engine yet (just put it together this past winter) but software shows it should be +/- 340 hp, but I built it more for torque than hp. Also there is no emissions testing in my state.

The 81 crank is a 2 bolt but that's sturdy enough for this setup as I don't spin it past 5,500 rpm.

The tranny in the 81 does not require the lockup be used. Earlier versions would burn themselves up within an hour if the lockup wasn't enabled. I'm going to do a 700r4 conversion later this year. Without the lockup the motor turns +/- 3,300 rpm at 75mph.

One thing you might consider is swapping out is the U joints for non greasable Spicers. That's money well spent if you plan on increasing the HP signifigantly.

Any advice you need email me off line.

 

I have an 82 Crossfire motor that had many problems. The previous owner converted it to carburetor. When I acquired the car, it still had lots of problems. I had to replace the carb and intake. But after a lot of small issues, the car runs great. I am getting ready to drop a 383 aluminum headed motor in. That should raise the horspower and wake the car up.

 

Do the distributor, too. It's not that much more $$$ (especially if you're spending euros or pounds sterling...)

 

Anyone recommend a distributor then?

I saw this Mallory one at summit http://www.summitracing.com/

Part # MAA-8548201C

What do you think?

 

Thanks for the compliment, I am hoping with the heads, intake and carb swap along with the distributor will hopefully yield around 300hp.

 

If you are going to go ahead change the HEI as well, simple job with the right bits. You can wire in a switch for the converter lock up without to much problem.

J.

 

Yep I will be changing the distributor aswell

 

The only thing my computer does on my 81 is keep my check engine light on... I'm too lazy to pull the bulb out, I'm just hoping it'll burn out. But my tranny is no longer the TH350C, it's just a regular TH350 now, stock carb and distributor are gone. Runs much better, so fast and furious.

 

Did you change the heads too?

 

My heads are the crap 882's. Stock I believe. They've had some good work done to them, but 882's are worth more as scrap metal. I have a set of 71 LT1 heads now that I just came across, and some aluminum L98 heads from an 89 Vette, so I may swap one of those sets onto the 81. Right now, the heads and exhaust manifolds are the only thing holding me back (Performance Wise)

 

I just saw the stuff you're buying. Nice intake and heads. What kind of rocker arms will you be using? If you're going on a budget, there's some nice 1.5 ratio stamped steel roller tip rocker arms on Summit for about $65. I bought them for my Camaro, and they seem to be good quality units. Do you have factory manifolds or headers on your Vette? I don't think you'll have any problems making 300hp to the wheels if you're running that stuff under your hood.

 

I change everything on my 350 to Edelbrock just kept the block and crank. The computer is history and she runs great.

 

Hi Paul,
As said above, if you're going to pull part of the system out then it'd make sense to rip it all out.
Wiring up the trans to lock the converter is easy, real easy. It'll run OK without being locked, but the 300rpm or so that it drops when it locks makes a substantial difference to the fuel economy.
300hp won't be difficult (especially with those dual pipes ), but it may be worth checking what your insurance company says about it. I just got a price hike due to the OD transmission. It's not a performance enhancing modification, but they still banged on a healthy increase because "it wasn't professionally installed" (just like the countless cars they insure without question where owners have swapped out blown engines & gearboxes with ones from breakers). If you are currently insured with Hill House Hammond then the new owners may have a surprise in store for you regarding any modifications....

p.s. Are you changing out the carb due to problems with it, or because you've been told it won't cope with new heads, etc?