Carb Question?
 

i just aquired an old Holley. the list number for it to look it up is -Holley 6210-
is this a good replacement for the old Q-jet on my 305?

if the carb on the car now is original, its an electronic quardajet and is hooked up to a basic type of ecu and works in tune with the distributor

so does that mean it wont work? if so, how can i fix this?

Should be a spread bore replacement for a Q-Jet, but if your 305 is stock it may be getting on the high side of "too much carb".

A 650?

The most popular carb for stock and mild 350 setups is a 600 vacuum secondary Holley. Note I didn't say "It's too much carb" I said it's getting there. You will probably be just fine as long as it's not a 650 double pumper (which it isn't, based on the LIST number).

As smoking said, though, you have an electronic Q-Jet so you will probably have to depricate or abandon your existing electronic engine management stuff.

Somebody who has done the conversion can probably guide you better than I can.

well its deffinately not a double pumper.

Unless your Q-Jet is WAY out of wack, you're NOT going to see any improvement on a STOCK engine, especially a 305. Make sure(if your looking for more power)to check things like plug wires-spark plugs-fuel filter-distributor cap-timing and more. Any combination of those not working well, will cost you power. It's not like having a BBC with 450 hp, and you lose 10-15 hp, you'll not really going to feel it. But lose 10-15 hp when you only have 145 hp is really going to hurt. :nod:

I did the swap when i pulled my 305 for a 350...the stock qjet is plenty of carb for the 305..i went 14.3 on it with the L69...once you switch the carb out to non computer control you need a non CC dist. as well..you can also lose the computer and pull the wire harness to....There are a bunch of free mods on third gen.org you can do with the CC qjet..I think i still have my qjet with all of that stuff done on it plus some extra rods and hangers to tune the secondaries...it would be a more efficent improvement then just putting the holley on it..

If you engine is stock leave the carb as is. If it's modded you can get different metering rod and such that will help. GM offered a kit years ago to put the ZZ4 engine into 3rdgens and it came with a different ECM and the carb parts. I doubt they still sell it but you can probably find the part numbers, and then get a chip burned.

I had a Compucam emmisions cam and Edelbrock headers in my 84 (305HO) and the stock carb feed it fine with only a few mods. There is a book ( I once had - Justin? ) that about modding Q-jets, some of the simply tricks work wonders!

The HPBooks Rochester Carburators book has a bunch of this stuff.

I thought I gave that back....I'll go check my bookshelf.

- Justin

then should i sell it? i'll have to rebuild it first.

-Tom

Damn kids!