[Tyroma]

Hello...

I have been looking for a kit for my Rochester 2 jet, and I am having trouble finding the number. I have gone through all the lists that I can find with no luck. Maybe one of you guys can help me.

here's the info:

-there are NO numbers anywhere on the exterior of the carb. The only marking is a GM inside of a circle, Rochester 2 jet, and a stylized RP on top the top plate.-i dissassembled the carb and found the numbers on the inside of the top plate
-those numbers are: 700 and then a circle with the following number 7012973 (and yes, i did check to see that the 7 is not a 1) and then a 58 inside a circle

What carb is this? What year is it? Which kit do I need?

thanks!

Ty

 

[willowbilly3]

The 7012973 looks like a rochester carb number but most of the older 2GCs had a tag under one of the screws.
It is a very simple carb and you should be able to get close on the year just by the looks. Is it a small base or large base? Maybe you could show a couple pictures of it.

 

[Tyroma]

The 7012973 looks like a rochester carb number but most of the older 2GCs had a tag under one of the screws.
It is a very simple carb and you should be able to get close on the year just by the looks. Is it a small base or large base? Maybe you could show a couple pictures of it.

Hey...

Thanks for the reply...there is no tag on the carb...probably removed and never replaced.

It appear to have a large base. Looks like this (this is not mine...)

http://fototime.com/ftweb/bin/ft.dll/picture?PictId={67BFC369-14F2-4DCE-8FD0-A4DE40229035}&size=orig

I'll snapyou some pics of mine tonight.

Ty

 

[willowbilly3]

The small base will measure 3 1/4" between the bolt holes and the large base will measure 3 11/16". I just went out and looked at some of mine. I have a large base with the style of base plate as the one you pictured. It still has a tag and the number is 7020046. If the number you have won't get you a kit, I'd almost bet the number I gave you will. Most kits are made to cover a wide number of variations in a similar model.

 

[willowbilly3]

After some research, I don't think the 701 number means anything. If it did, the digit 1 would seem to indicate the 50s (3rd digit 2 is 60s anyway) and they never made a large base in the 50s to the best of my knowledge.
Here is some good info but you still need a number.
http://www.holisticpage.com/camaro/parts/carb.htm

and

http://www.oldengine.org/unfaq/leadfoot/qjet1.htm

 

[Tyroma]

After some research, I don't think the 701 number means anything. If it did, the digit 1 would seem to indicate the 50s (3rd digit 2 is 60s anyway) and they never made a large base in the 50s to the best of my knowledge.
Here is some good info but you still need a number.
http://www.holisticpage.com/camaro/parts/carb.htm

and

http://www.oldengine.org/unfaq/leadfoot/qjet1.htm

Hey...

thanks for doing all this legwork for me! I will take some measurements of the carb when I get home tonight. Based on the de-code formula from the second link, here's what I came up with...

7012973

70 - Rochester Products division
12 - as you figured, 1950's...possibly 58 (as there is a circled 58 stamp?)
9 - carb id ????
7 - Pontiac division
3 - manual transmission

I will let you know the base size, and send some pics.

thanks!

 

[Tyroma]

Hey...

Here are the pics of the carb...let me know what you think!

Ty

 

[willowbilly3]

Small base, that would explain the earlier number but according to the 2 reference articles the cast numbers in a circle don't jive. Maybe they had the tag AND also cast the numbers in. Was it a manual choke or is that a modification? Do you have all the missing parts?

 

[Tyroma]

Small base, that would explain the earlier number but according to the 2 reference articles the cast numbers in a circle don't jive. Maybe they had the tag AND also cast the numbers in. Was it a manual choke or is that a modification? Do you have all the missing parts?

Ah...makes sense. Manual choke, and yes, I have all the bits. I just put it together for the pics.

So...based on the pics, do you have a kit estimate for me?

TY

 

[willowbilly3]

Factory manual choke would most likely mean it's from a pickup. According to this site,
http://www.carbkitsource.com/carbs/catalog/Chevrolet/Chevy8-1961-76.htm
it would almost assuredly be a CK22 kit.

 

[cobalt327]

Small base, that would explain the earlier number but according to the 2 reference articles the cast numbers in a circle don't jive. Maybe they had the tag AND also cast the numbers in.

CAST numbers are ID for the casting itself. The only numbers that will translate to the vehicle or application will be either a tag (this carb would have had a tag) or STAMPED numbers.

Your small base carb w/divorced choke was used from about '55 until about '68, it was used w/a different choke arrangement later (~1973), on the 307 SBC.

I agree the CK22 kit will be the one to use, no doubt.

 

[Tyroma]

FANTASTIC! Thanks guys! I've got the kit ordered up.

TY

 

[Tyroma]

Hey...

Got the kit today...then got to thinking "hmmm...wonder if that small carb is gonna fit my intake?"

Nope! I have the car with the 3 1/4 x 1 7/8 and I have the manifold with 3 3/4 x 2..!arg!

Summit racing doesn't have an adapter for this application...any of you guys know if there is one?

Thanks

Ty

 

[cobalt327]

Summit racing doesn't have an adapter for this application...any of you guys know if there is one?

I think you're outta luck unless you wanted (and had room under the hood) to use a pair of adapters like the Trans Dapt P/N 2039 and 2040. $78 plus S&H from Jegs.

 

[willowbilly3]

Bummer. I have a couple core large base carbs which I don't have any plans for. If it would help you out, I'd part with one, maybe a trade of some sort.

 

[Tyroma]

Yeah...I thought as much. Arg.

I have the kit now, so I guess I will rebuild this one, and then sell it as such. If I can make a few bucks, then I'll put the cash towards the right one.

Thanks for the offer, Willowbilly, but I'll try to track one down a bit closer to home. Thanks again for your assistance on this matter.

Ty

 

[Tyroma]

Bummer. I have a couple core large base carbs which I don't have any plans for. If it would help you out, I'd part with one, maybe a trade of some sort.

Might be a silly question, but I don't suppose a large base will bolt onto this carb, would it?

TY

 

[cobalt327]

Might be a silly question, but I don't suppose a large base will bolt onto this carb, would it?

TY

Reasonable question, but the throttle bores are considerably different- 1-7/16" (small base) to 1-11/16" (large base). This means there'd be a big mismatch at the bottom of the carb throat before the venturi, even if it fit otherwise.