I recently purchased a 1981 vette. Someone has removed the electronic carb setup and replaced it with a 1995 c1500 throttle body injection, added a second ecu from the truck (the old one is still installed) and replaced the distriutor with the one from the truck but I'm not sure how any thing is wired. They have also installed vortex heads and XE249H comp cam. It runs good but because I no nothing about how it's setup I would just like to go to a straight 4bbl setup. What parts would I need and what wiring changes would be required for the distributor and the trans lockup converter. If necessary I can replace the truck distributor.

Thanks for any input,
Dennis

 

Welcome to the forum. Both the C 1500 2WD's and K 1500 4WD's used pretty much the same systems. They are reliable and if it's running fine, you may want to stick with it. You can do some research on how the system runs, but it's not that complicated.

I would say your only issue, would be diagnosing any trouble codes etc. Normally for a 1995 you should have the following:

ECM P/N 16197427
(2wd and 4wd, 1/2 ton and 3/4 ton)
-5.7L TBI / GAS
4l60E Auto Trans
3.73 and 3.42 axle ratio

I don't have any info for a truck that was a manual trans. (that possibly may have been a better option since it's "possible" that without any input from the 4L60e (unless that was swapped into your car), the ECM could possibly be in a "limp home" mode / reducing power. (I'm more familiar with some older ECM's from a few TBI conversions I've done in the past (Early to mid 90's ECM's) -

I'd say if it's running fine, your gas mileage is good and it seems to have power, it may be worth sticking with it. (It "should" / if working properly, provide good power AND good gas mileage. Most likely better than a 4BBL carb).

 

I would agree with that assessment. Why change something that is working? Any chance you can investigate to see who swapped it over? Maybe contact them and find out what was done.

IMO, someone knew a lot about this conversion and probably did all the things necessary to get the system up and running well. It should be an OBD-II type system, so you can diagnose problems with a code reader. You can even go to an auto parts place and have them use their code reader to dump codes on your system.

 

One thing that I didn't mention until I read 7T1vette's post just now:

1995 was "a bit odd". It's not unusual to find and OBD-1 system with OBD-2 connector.

There were some issues / confusion at the time but if I remember correctly - you could use an OBD-2 reader BUT reference the OBD-1 malfunction codes if the system used the OBD-2 connector (which many did). IIRC, there was an adapter for the other / older connector.

I did a few TBI swaps (1989, 1991 mostly) and I believe a 1993, but things got a bit "different" and I'm not really into the replica / kit cars that much any longer so I'm no longer "up on it".

Normally what I would look for at the time (not that it will help in your case) is: Was the underhood sticker that referenced OBD-1 or OBD-2. I think you'll find that 1995 will most likely be OBD-1.

You could do a few searches on the K-1500 / C1500 forums to find out. I do know that there is quite a bit of talk on some of the S-10 forums about OBD-1 with OBD-2 connector / how to read codes etc .

Also, It's quite possible since most all of those S-10's used the same system (but with the 4.3 liter engines), that maybe you may luck out / as "possibly" the full sized trucks w/ V8 made the transition to OBD-2 sooner.

Either way, you should be able to check for the Readiness Codes with any old OBD-2 scanner and determine what you have there. FWIW, the OBD-1 system / TBI V8 trucks had decent torque, ran well etc so again..... if it seems "solid", possibly have some fun with it..

 

Did they use an adapter or the Edelbrock intake with Vortec bolt pattern that accepts a TBI? If so, that intake is worth something even when used. That setup can be tweaked to provide reliable performance, you might want to stick with it.