gt500pwr

Has anyone used the ExtremeFI 50mm bored out tbi units? I picked up a 502-6 holley unit, i'm just wondering if I should maybe go with one of their units instead so I don't have to mess with any wiring or linkages on the holley (I also have someone interested in it). They say theirs' flow 750cfm with the ultimate mods.

Thanks.

gt500pwr

All these TBIers and nobody has anything to say regarding Extremefi's throttle bodies? Not a good sign...

eschevyrda

lol right people or just lazy to reply

but ahh i heard that the extremes are real good and even better then the holley 670s but who knows im also looking for a new throttle body hmmm i thought about the holly commander but dam thats to much money for that but then agian u get wat u payed for

BMmonteSS

50mm is 50mm doesn't really matter who makes it. You can't really do the ultimate TBI mods to a 50mm throttle body since there isn't a ridge like the stock sb units.

Colts45s

honestly i feel like keeping stock unit doing ultimate tbi mods is the way to go esp. if you go with the 68lb/hr cop car injectors with a walbro 190 fuel pump

gt500pwr

What tb unit do you run BMmonteSS? I was mostly curious whether or not the extremefi unit would be a better choice from a plug & play perspective. They claim theirs flows about 80cfm more than the holley. I was just wondering if anyone has actually used it. This will be fueling a 383 so I want to make sure I get the right unit so as not to starve the engine.

Fast355

iTrader: (2)

To 340 FWHP and about 5,000 rpm you really don't need anything more than a standard TBI unit on a single plane intake (kill a little torque so you can get out of the hole) with ultimate TBI mods and an injector spacer. I am running a 46mm bored TBI unit by Xtremefi on my 350, I see no problem with it. I have also run BBC TBI units, they are easy to setup if you do your research. Even the lack of a TV cable provision is easily fixed with a little research and fabrication.

BMmonteSS

I'm running a BB unit, I had to fabricate the throttle linkage because I swaped TBI into a carbureted car. You'll also have to get the correct connectors for the IAC and TPS. They may or may not match up with your stock connectors.

As for the extreme unit flowing more than the holley.....they don't do anything to their TB's that you couldn't do to your own. My guess is they radius the entry into the throttle bores a bit and add an injector spacer and claim the 80 cfm. In the end it really doesn't matter, I picked up my TB for $20 so I made it work. You also need to make sure your getting the bigger injectors with the extreme EFI unit. 80/90 lb injectors aren't cheap, but if your getting them with they BB unit then it could be much cheaper in the long run.