Opions please... I have a 350 SBO at ~9.5:1 CR, stock cam (do not know specs), with Edelbrock Performer 350 intake, #5 heads, small valves, headers, true dual 2.25 exhaust with a 350th auto. running a stock HEI dist.

Right now it has an "out of box" Holley 1850 for a carb. I want to go back to a QJet. I have found a 7042251, '72 455 carb. It is on a running Olds 400 in a '77 Firebird. I do not know any other specs. It was home rebuilt 18 months ago by the owners step dad. The FBird owner wants to go all Edelbrock, heads carb, intake etc.

Anyways, If this 7042251 is running well on this engine, do you think it is too much as is for my 350?

In the tech section here on CO is lists these specs for the '72 and stock '68 if I had one. I do not know enough about the internals of a carb to know what the numbers mean.

Year Application Carb # Main Jet Primary Rod Secondary Rod
'68 350 7028250 7031971 7034849- "49B" 7033658- "AT"
'70 455 7042251 7031969 7034850- "50B" 7045779- "CH"


Please adavise. Thanks

Adam

 

Don't know what altitude you're at, but those numbers are at sea level - IMO you should be good to go, especially if your geared over 3:08.
A litte timing would work, too!

 

you'll be a little rich on the 350. the 455 carb. also uses a different power piston spring. you may end up with a bit of a "quadraslob".


bill

 

Let us know how it worked out!!

 

Can the power piston spring be changed easily? I have agreed to buy, it will be about a week before he tears his engine. I figured for $75 I can not go wrong. That's what non functional cores go for on ebay. When I get the time to switch will be another story, but I will let you all know.
Bill, If you have any advice on changes I should make I would really like to hear them. I notice you post a lot re:carbs and really seem to know your stuff.

Adam

 

it is easy to change a power piston spring providing you have an air horn to float bowl gasket(and know your way around the inside of a qj). selecting and obtaining the right power piston spring is the hardest part. i'll save you the trouble of selecting it, at least, gm/delco p/n 7036019 is what you're looking for. there are some out there, your dealer may need to do a locate on it.


bill

 

Hi Bill, I stole a quote from another of your posts on a different thread. I am looking for a delco 7036019 spring and can not find a local dealer. Advance Auto Parts sells an Edelbrock spring kit ....

http://shop.advanceautoparts.com/web...7CGRP2030P____

It includes these four springs: 4"Hg, 5"Hg, 6"Hg, and 8"Hg. If I used the 8"Hg spring from this kit I should ok, right?

Thanks Bill


Adam

 

I got my 7042251 this weekend, not on the car yet. It was abit of a funny story.
The owner's step dad called me. He asked if I was still buying it for the agreed and handshaked $75. I told him I was and that I was waiting for him step son to call me. Step dad says there is a guy at his door with $125 for the carb. The step dad has not seen this guy before and knew I said I wanted it. The step son/onwer is not home but will be back in about 3 hours. The step dad tells me to come pick it up for the agreed $75, cash, and he will deal with the "little sh*t step son." I was there in 15 minutes and the $125 guy was still sitting in the car waiting for the step son to get home.

The step dad said he had taken the carb off and cleaned any dust/dirt/grime and did a full clean up while still on the car. He couldn't get it spotless but did the best he could. Then I opened the box it was in. It practically looks new in box (less the di-chromate coating). I hope he was being sarcastic.

Here's what it looks like.





Nice beautiful intact threads....



I think I scored quite the deal. I wonder how the step son /step dad relationship is going. Oh well, I picked it up on Saturday morning and it is noe Tuesday and I have not had a call about it. I think I am clear.

Adam

 

that's not what they looked like new. i hope that "repair" on the accelerator pump lever hinge holds-up, i've seen it done better. that reminds me of a cardone rebuild with the green coloring. if it runs decently-you did ok.


bill