RGV_Z28

iTrader: (7)

I know people port the 90mm version, but can you do that to the 78mm also? Is it easy to do and who can port it? What kind of gains are people seeing? Thanks guys.

Hennytime

iTrader: (33)

yes it was done recently, i think he ported it to 85mm

radkon

iTrader: (2)

Specify which type of porting:

Internal runner porting: yep you can do it just like the 90.
Port matching the intake to the heads: Yep
TB opening porting (haven't really seen or hear it but I suppose you can open it up a bit).

edwardswb

iTrader: (6)

I've wondered the same thing. I thought about porting my fast 78tb as well, but I don't know if it's worth any gain whatsoever to go messing with a $$$ tb.

BlackScreaminMachine

iTrader: (17)

Subscribing....

Friend had a 78mm Fast and eventually may step up the the 90 intake and doesnt want to respend the money.

LS1Formulation

iTrader: (13)

I ported a 78MM FAST to fit an 85MM TB. You can do all of the same mods to a 78 as you can to a 90. There's not much power difference between the two, no matter what you hear.

vettenuts

iTrader: (4)

There was a thread on this recently. The 78 is always downplayed, but most people don't realize the 78 and 90 are the same except for the opening. It can be ported and the results will lie on top of the 90 up til about 5,500 RPM. Contact Tony Mamo for porting.