mjohn

Looking for someone whose built a twin 2 barrel TBI motor that could help me navigate around any pitfalls, Ive talked to rbob and feel comfortable that it can be done, just wanted to visit with someone that has already done a build like this.

Thx

Fast355

iTrader: (2)

I have setup and tuned one. Pulled a pair of 500 cfm Edelbrocks off a tunnel ram on a nasty solid roller cammed 406 in a 1939 Chevy Sedan. At the time I built my own injector amplifier/peak & hold driver to power the additional 2 injectors with an otherwise stock 1993-1995 TBI PCM. It had an electronically shifted 4L80E behind it as well. I parallel plumbed the TBI units and set them up on an adjustable regulator with vacuum reference. Ran about 20 psi at WOT and about 13 psi at idle. I wired both IACs in parallel and tweaked the tuning to run them properly. The TBI units were both mounted on water heated Holley Projection adapters. The air cleaner was a custom setup with a pair of transmission coolers to preheat the air via coolant. The hot water ran from the back of the intake, through a ball valve, split to each of the projection adapters then through the cores before being returned to a fitting above the thermostat in the water outlet. The tunnel ram really liked being heated.

Buccaneer

This is interesting. I didn't know of anyone that had done this with two twin injector TBs...Nice! What did it run ET wise or hadn't you done that with it? Any pics of the setup that you can post? I'm sure Mike would love to see them. Also, from what I understand, rBob's Flash II can be setup for the extra injector drivers if someone wants it. Maybe Bob will chime in on that. BTW, Bob if you read this I found my power issue, strange what it was doing, but it was a good fix. It all seems to work fine again.

Fast355

iTrader: (2)

I don't have any pics surviving of this setup. I do know it ran 11s in the 1/4.

As for dual TBI setups. Mercury marine had a 575 HP marine big block the 575 SCI with dual TBIs on a blower. Pump gas motor running only 5 psi of boost. Made that 575 HP at only 5,100 rpm. I know with the addition of an air to water intercooler, a pulley swap and a raised rev limiter they would make 700 hp at 7 psi boost.

mjohn

Thanks for getting back to me and for sharing all your information, Any ideas on where to get a gm marine style VAFPR or equivalent, part # maybee

Thanks
Mike