Anyone know what the jet sizes were in the early 2GC tri power set ups on 283s? Got a new set up from vintage speed and the .057s that are in seem to be dumping too much. Thanks, J
I started with .057's in my 350 tripower center carb and they seem to work well. In search of fuel economy I've recently installed a pair of .055's...though that is leaner than GM used on the 348's (the closest displacement to a 350). I'm going to try them for a while to see how they work. Something else to look at...Charlie pitches his fancy****ed teflon disc****embly to replace the normal needle and seat set up. I drank the koolaid and tried them...they don't work...even with a fuel regulator dialed as low as it could go...the carbs would flood fuel at idle. I threw away the teflon disc****emblies, and used regular needle and seat****emblies...problem solved.
BTW, I used Mike's Carburetor website to find a very comprehensive listing of jet sizing for the Rochester 2G's. https://www.carburetor-parts.com/2-jet-main-jet-specifications
You will drive on the center one 90% of the time, so set it up like a stock 2 barrel engine. Post the carburetor number, I have a bunch of Rochester papers I can look through.
A 9-1 in the mid 60’s compression ratio 283 SBC used 52 jets stock…it’s not the cubic inches, it’s the compression ratio. Its fuel to air thru the venturi. 10-1 would be slightly higher.
I think that is where mine came from. Was told he’s the guru. They were junk! None of the six throttle blades seated and on first startup fuel running out if the right header. Nice on a brand new motor I’m trying to break in. I took them all apart and fixed them. Oh yeah, they came with.056 and .058 jets. That did seem to be about right. Probably dumping fuel because the throttle plates won’t seal.
I ordered a set of Holley 94 jets from them and received a pair of used jets; to add insult to injury, one was the wrong size. I then decided it might be a good idea to call them and complain. It wasn't. I'm just lucky I learned on a measly set of jets. Many similar tales here and elsewhere. Some people have gotten lucky and received good stuff. Unfortunately, "luck" doesn't enter in the equation when I am ordering parts.
Up there in Breezy Point you also have to figure in the diameter of a mosquito in case one should be ingested. It’s all part of the MN State mosquito stocking program (grew up a bit south of you - love MN!). John
Bummer to hear the bad stories about Charlie. Those carbs were $$$. I had a hunch when a small fuel leak made his finish turn black. I called and told him and he said it wasn't possible...after I watched it happen in real time. Dude comes across as a guru expert. I never had a doubt to be honest
I usually let stuff like this pass, but this time, I feel compelled to ask you : "What the hell are you talking about"?
You are also running 283 cubic inches though one lawn mower air filter. Factory filters almost touch each other and they were marginal.
Yep we all run our 3-2 setups wide open at all times starving them for air….Funny that Pontiac GTO’s had lawn mower filters as you say from the factory and they didn’t run out of air…
Since I was paged: Chevrolet 283 CID engines ran a variety of jet sizes in the Rochester 2-GC carbs over the years, but the two most common sizes were 0.051 and 0.052 inch. These would vary depending on transmission type, application, air bleed size, etc. Without knowing the identification number of the carburetor, impossible to say. Basically, start with a rich configuration, and tune from there. As for the filters, tests done by Pontiac in the early '60's clearly showed the large air cleaner that covered all three carbs was superior to the pie pans, but even then, "looks" was more important than performance. The ill-fated Pontiac Super Duty aluminum tripower (TRY to make a tripower run as well as a four barrel) used the large air cleaner with no snorkels, and seven snorkel sized holes around the perimeter of the air cleaner. Even this set-up did not make the tripower competitive (but the tripower looked nice!). Jon
I'll put in my 2 cents worth. I installed my tripower kit from vintage speed about 3 years ago including the disk****emblies on a stock 283 and have been very happy with the results. I am using the 4" air filters from speedway. I do kind of drive like an old man so I'm sure I'm not taxing the induction system at all. Phil
.054 Carbs rebuilt by Bobby Blake. NASCAR carb expert. Starts so good. Runs so good. Never checked the plugs. .040 bore x stock stroke. PS; Yes an Edmunds intake made for 4 bolt carbs
I stupidly passed on one about 5 years ago because I thought $400 was too much. After my experience with one 2G on a 255 Merc, I have to believe one of these would be ideal for a big inch flathead.
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