I have an old Chromed offy sbc tripower intake for large base Rochesters and need to know some stuff, first what carbs should i look for, did they come in side inlet, and how much overkill is it on a hot 283? Also anyone have some decent chromed ones under foot?
As these carbs were origional to the 389 GTO and big block Olds tri-power I'm thinking a bit overkill for a 283. I'm sure you'll get other opinions. Frank
Have a friend on here that used to run a single Rochestor 2G with the end cabs blocked on a 327 in a '29 on '32 rails and it hauled ***! Just a thought if you don't want to over carb.
most of the large base carb i know of were front feed..........and they also came on 350's so 3 of them is WAY overkill on a 283. like jimA said mabe block off 2 and run the center only.
Don't forget that CFM ratings differ for 2 vs 4 barrel - they're flowed at different pressures. The big 3X2 carbs all together are supposed to be around 950 CFM, yet a 750 is comparable? There are 500 CFM 2 bbls out there, and that's definitely a little high by 4 bbl standards... HTH.
I've heard the bases of the large ones can be swapped to house the bodies of the smaller ones. This is what my mate is about to try...someone confirm this??
another thought is to run 2 carbs & block out 1 of them. Give ya a little more CFM if you did head work & cam JimV
Are you setting it up to race or run on the street? When do you get all those CFMs? at WOT. Progressive linkage should make it run well on the street until you floor it. It'll probably stumble and fall on it's face because there is insufficient air flow to atomize the fuel properly. You might be able to build an adjustable stop in the linkage that would limit the ****erfly travel of the end carbs. That would keep the velocity up in the carbs. Basically limiting the CFM. But if it were me I'd just redrill the intake for smaller carbs. It may be necessary to plug or weld up the old holes. If you redrill for the 97/94 3 bolt type carbs you might not need to plug the holes except for cosmetics. The most trouble free hot rod I ever had was a 305 that ran a box stock 71 Camaro 2bbl Rochester on a 3 deuce intake with dummy end carbs.
Yea if i have them on the intake i'm gunna run them, but i figured u guys would say this, As the motor goes it will have power packs punched out to 194's and ported, duntov 30-30, and probably a little over 10 to 1, decent for a street motor. I may just have to set up the outside 2 to start when i get my foot way into it
The Jalopy Journal
