Abdullah

iTrader: (2)

is the difference between the Fast 92mm intake and the Fast 90mm is only the throttle body inlet size which is 92mm Vs. 90mm and the ports are the same shape and size for each intake?

that is if i port the throttle body inlet in the 90mm Fast to 92mm it will be just a 92mm Fast intake exactly?

thanks for help.

LS1Formulation

iTrader: (13)

You might be able to port the intake from 90 to 92MM, but is it really worth it? In my opinion, it's not. I took a FAST 78 and ported it to an 85MM and THAT was well worth it, but going up 2MM isn't going to be a really noticable difference. Here's my thread on how to do it: https://ls1tech.com/forums/generatio...5-85-pics.html

Abdullah

iTrader: (2)

so from what i read in your modified 78mm Fast intake post if i port the 78mm Fast to 90mm it will be just like the 90mm Fast, correct?

and so is for the 90mm Fast if i port it to 92mm it will be just like the 92mm Fast, correct?

i think i will try to open my 90mm Fast to 95mm or even 100mm if the throttle body and a 100mm MAF will fit under my car's hood.

LS1Formulation

iTrader: (13)

You can only port it to the outside diameter of the factory O-ring seal. Any farther and you'll have leaks. I'm not sure how far you could take a FAST 90 or if it's even possible - I've never messed with one. On mine, you could only port it to 85MM, any farther and it'd be screwed.

Abdullah

iTrader: (2)

thanks, good info. i will see how far can i go with my 90mm Fast. Vengeance took the 92mm Fast to 96mm with 96mm Nick Williams TB and they gained
7rwhp/13rwtq over ported 92mm Fast, i don't know if this is the farthest you can go with the 92mm Fast.

i asked a tech @ Fast company and he told me that every thing between the 90mm Fast and 92mm Fast are exactly the same for ports shape and volume and inner parts and design except for the TB inlet which is 90mm for one and 92mm for the other that is if i open the 90mm Fast to 92mm it will exactly the same or it will performa exactly the same as 92mm Fast.

Abdullah

iTrader: (2)

i just got an idea, why not to replace the upper part of the 90mm Fast with a 92mm unit, will the 92mm upper part fit the 90mm lower part(s)? that way you will get a 92mm Fast.

DVS99TRANS

iTrader: (7)

Sell you old FAST and buy a ported one in my opinion. If you mess up you are out of a grand if you see what I am saying. The FAST92 has been taken to 100mm TB opening from what I have seen, but can't remember who does it. Think it might be RevXtreme, Vengence, or TSP but can't recall. I have mine ported to 95mm with a matching TB. I also nothiced that the cathederal ports where opened also, not sure whatelse but haven't taken it apart to look.

Abdullah

iTrader: (2)

i also like the idea of selling my old 90mm Fast and getting a new ported
92mm Fast from Vengeance instead of missing with replacing parts from the 90mm Fast.

what size your Fast is? is it 90mm or 92mm? is it ported or not? and by who?