Anyone have an early turbo regal Q jet or info on mods for boost? I'm not trying to cheep out here I just want try boosting 8.5 psi through a q jet to proove it can be done. Info or suggestions welcome!
Hey Sean, The carb turbo 3.8 motors were "Suck thru" designs. Same thing on the Pontiac 301 turbos... I don't any info on them will help you with a "Blow thru" design like your trying to do. You would have to have carb adapters made to mount on the turbos inlet side, so the fuel/air would get "sucked" out of them through the turbo then into the manifold....this is not a very efficient setup although its possible. I remember seeing a Dodge Challenger at Carlysle in the early 90s that had a setup like that on a 340. He said it ran good at WOT, but start up was hell no matter hot or cold. Oh and he had 650 Double pumpers on it, if that helps at all.
Thanks for the info, this may not go any farther since it does not sound feasable. Thanks for the info!
I still have the '79 Turbo Regal I put together back in '86. Original draw-thru setup using a Q-jet. Ran low 14's on around 16 lbs of boost. Started up and ran great, but turbo lag was about 2 seconds from a dead stomp! Still a very Fun car. Been thinking about a blow-thru setup with an intercooler....that's the way to go!
i have had one ,the turbo has nothing to do with the q-jet the turbo will pressureize air and fuel with that design not really what your trying to do you would need to modify the secondarys to open under pressure and and make it pull fuel thru venturi under pressure rather then vacuum basicly make the carb work backwards from its design alot easier to use something else
No, the carburator will still function in a blow-thru setup. A carburator works on a pressure differential.... On the engine side, it produces a vacuum (or low pressure) during the intake stroke. On the inlet side, there is atmospheric pressure (14.7 lbs). Add a turbo, and you are basicly increasing the pressure on the inlet side.....you will still have the lower pressure on the engine side, and the carb will function. You will however, need to increase fuel pressure to a pressure greater than the boost pressure. Carb float collapse could be an issue (use a foam float), and vacuum lines will need a check valve, or be relocated. Blo-thru setups have become popular lately due to their simplicity, adaptability to carbed engines, lower cost, and the fact that they just plain work!
yes but the secondarys have to bring the valves open by vacuum which is what pulls the fuel thru the venturis with out that it wont meter the fuel it will just dump it creating another problem-too rich and the secondary valve plates work from vacuum no one makes a valve that goes the other way so you are talking make yourself you can get it to work but tuning will be a tremendous task not worth all the work but use the quad as a throttle body and fuel inject engine you will be ok
i know theres a site on how to mod a qet for blow through, its harder to comepletly seal a q-jet compared to the others but its been done.. see if i can find that site again
