JLCustomizing

Im rebuilding a seperate carb for my 84 t/a since it has a 81-85 chevy truck carb on it and that carb itself needed some work. I bought a 82 t/a carb that I am currently tearing apart and getting ready for rebuild. I was wondering since my car was redone with a 350, stage 2 cam, keith black flattop pistons, bored .60 over, and 305 h.o heads with 3 way valve job should I jet the carb higher? What size jets would I need? Also is there anything else I should upgrade on the carb to handle the larger engine? I want to maintain some gas mileage so I dont want a race car but just a little added power.

travis401

iTrader: (1)

is it a quadrajet carb? if so, is it a CC model, or non CC model?

89RsPower!

What the heck is a "stage 2" cam? A .060 over bore is another way of saying on its last rebuild. Some guys will find another block to build before going that route (.060 over), some people will say it's fine to over bore an older seasoned engine since they are less likely to experiance core shift due to "stronger" blocks with a higher nickel content (refering to early to mid 70's castings) but not newer castings. From my personal experiece running an early 90's 350 casting (yes I know that a block alone doesn't have a set CID since 4in. bore blocks were used with various cranks which when paired togathe determine the size) with a .060 over bore as a very mild build experienced no real issues except it ran a bit too hot for the factory cooling system but was resolved with a larger rad, stewarts stage 2 water pump, and a 170 thermostat.
So back to the question, most likely you will need to do some trial and error tuneing to get it running at its best. Info such as cam specs (or the manufacturers name and part #), converter stall speed and rear gear ratio may help to make educated suggestions as to where to start and where to go. Also very important question: CC or non-CC carb? CC or vac advance dist? If u have a non-cc carb u need a vacc advance dist to make it run right.

travis401

iTrader: (1)

id be more concerned about the flat top pistons on possible 58cc 305 heads causing a crazy high CR.

JLCustomizing

Its a cc carb and the block is a 77 chevy 350 block. I bought the engine with this build so I'm not 100% sure of whats under there minus what I had for reciepts. The cam I can get more info on it just said stage 2 cam install. Why he kept the 305 heads im unsure as well. Ill get a jet set and play with the different sizes to see what I come up with.

travis401

iTrader: (1)

from my little understanding of the q-jet carbs, you dont wanna mess with the front jets, and the only thing you really need to do to the secondaries is a rod and hanger change. the computer should take care of the rest with a tune.

im sure five7kid will chime in with the correct info eventually.

five7kid

iTrader: (14)

You're kidding, right?

Depends upon the cam. If it has a lot of overlap or low LSA, it may confuse the poor O2 at idle/low RPMs.

"Stage 2" is an open book. Could be too much for the computer, could be RV cam level.

travis401

iTrader: (1)

you cant resist a q-jet thread. its like honey to a bear....

JLCustomizing

If I wanted to update the computer to handle it since I know the lift is quite high what route would I go, chip the current computer or pull one from another car?

InfernalVortex

iTrader: (4)

http://www.eficonnection.com/eficonn...omponents.aspx

Since it's an 84, just put a non computer controlled carb and non computer dizzy on it and call it a day. No longer matters.

You will still need to learn to tune it.

89RsPower!

^ That would make the most sense unless you can find out the cam specs or replace it with one with specs you know. That way the computer is out of the equation by simply swapping in a vaccum advance dist and a non-cc carb. Then you can simply tune it like any old school carbed setup.

89RsPower!

Another question to ask would be is the origional CC Q-jet and CC dist still present considering someone already removed the origional engine...