VCCA Home Forums TECHNICAL - 1945 AND NEWER 1971-1979 Bay City Rockchester 2 Jet

Hey everyone.
Ive got an old Bay City 2 Jet that I put on a 305 (kindof a Frankenstein engine) and I'm needing some information on tricking it out a bit. Specifically the jets. I've heard Quadrajet jets will work, but I have my doubts on that seeing that its a 2 jet and not a dual jet. Any information on this would be greatly appreciated. Thanks.

I've never heard of such an animal. Is it an aftermarket carb? Photos and/or casting numbers may help others chime in. Do you have any handy?

I've had a few of late 60s or early 70s that had the Bay City two barrel carb. Not one of the best tend to hesitate on acceleration if they are not set up 100%.

Its a stock carb. Just a big two barrel. It does't do bad on hesitation, just wnating to play with it more than anything. My old man used to use them on his circle track cars and drag truck so I know it can be done. Unfortunatly hes not around to ask. Ill have some pictures of it tonight.

Bay City,Mi carbs were an over flow supplier to Rochester.They are simply an OEM back up supplier.I've had 3 of these BC 2bbl's and I don't think they are as good as the Rochester units.The castings look rougher,imo.

alftoben,I think you're referring to the larger Rochester/Bay City 2 bbl's that came on the 396/265hp and the 70-75 400 2bbl engines.These had a larger cfm rating and larger venturi surface area's. The larger 2GC/2GV's are popular with alot of the dirt/oval track racers due to the rules.

I've modified a couple of my Rochester 2bbl's by opening up the stock jets by one size using wire guage drill bits.I sized the correct fit into a stock jet then went up to next guage drill bit and drilled them out.Also,slight float adj to compensate.Also a slightly taller accel pump helps.Of course use a big open element air cleaner set up.
But honestly,I don't think it's worth doing to a 305 sbc if keeping the stock heads,cam,etc.. My experiences,Jim

Well its different stock 305 stuff thrown together. 305 vortec block with 305 ho comaro heads from the 80s, the matching 2 barrel aluminum gm intake and a class one performance melling cam made to optimize low end torque. I built it for a hot rod and ended up needing an engine for my old truck so it went into my 76 k10 kindof on the fly. Im really satisfied with the engine in that big of a truck it actually pulls plenty of power and still gets 18 to 20 mpg in an all time 4wd. Yes i do believe that is the one youre talking about off of the 400s and the big blocks. It does a good job but a little more fuel would not hurt.

Hi Daryl,
I've had 4 Bay City Rochester 2bbl Chevy's over the years.Everyone had a Bowtie stamp with a BC in the center of it.
The Rochester produced carbs do not have this.
The BC Bowtie is right on top of the carb next to fuel inlet.
I wish they'd let us post pics in these replies.I have a great pic of this from my 76 Impala. Jim

Please elaborate a bit on this problem.

I can't figure out how to put a picture in,for example,this post.
It seems that I can only put pictures into the member's photos section.

You have the proper authority to wade around in the member's area. What you need is to spend some time in the FAQs and study the one on posting pictures.

Thanks Ray I'll hit the members area FAQ see what I can dig up!

Hi Jim,

Thanks for shedding some light on this subject. I learned something new today and that's why I love this hobby. So no Rochester markings on them at all? I know Edelbrock also made up some Rochester Q-jets with OEM castings...did they sell / lease the rights for certain models they didn't want to make or couldn't make enough of?

Pictures show up in posts if you use a third-party image hosting service such as Photobucket, Flickr or ImageShack. You'll have to copy the URL and paste it using the "Enter an image" link on the top of the chat window. (I think this is done to save bandwidth?) Its a little clunky but it works.

Bay City carbs were basically a 2nd resource or sub-contractor supplier for Rochester.GM didn't care as long as the carbs were built to the GM/Rochester contractual specs,imo.

Much like GM used McKinnon Industries when Flint Engine couldn't handle demands for SBC's or was tooling for next model year changes.I had a McKinnon Industries 350 sbc in a late in the model year built 70 Impala.Excellent engine.