MFI Throttle body ID

1972_911t · Post by **1972_911t** » Thu Oct 05, 2006 11:15 pm

Can anyone ID me some MFI throttle bodies, they have a 38mm inlet and a 36mm port size, there stamped 02 03 079.

There supposed to be from a 2.2S can anyone confirm this?

Thanks Steve

Lightweight_911 · Post by **Lightweight_911** » Thu Oct 05, 2006 11:23 pm

All S throttle bodies - 2.0/2.2/2.4 - have those same dimensions.

Can you post a picture ?

1972_911t · Post by **1972_911t** » Thu Oct 05, 2006 11:34 pm

Steve

Lightweight_911 · Post by **Lightweight_911** » Thu Oct 05, 2006 11:54 pm

Those look like 2.4S throttle bodies & 2.2 magnesium stacks...

- not a problem though - they will work together.

Is the diameter of the bottom of the stacks also 38mm ? If so, then they're 2.2S stacks.

1972_911t · Post by **1972_911t** » Fri Oct 06, 2006 7:48 am

Yes the bottom of the stacks is 38mm also. Ive just been looking at some pics of 2.2 tb's and they dont have the lower brace between the bodies so these as you say must be 2.4. The problem is I was hoping to have these bored out to work on a 3.2 which supposedly can only be done on 69 - 71 tb's. I dont think these have enough material on them

Steve

davidppp · Post by **davidppp** » Fri Oct 06, 2006 8:50 am

Hello, Steve.

Depens what you want to achieve really:

The real advantage of ITB's is to allow a big lumpy cam..and this will obviously demand lotsa air.

Simple geometry would suggest that to provide 3.2L with the same intake area/per Litre of capacity as the 2.0S for example would imply a diameter of 52mm.

(This onviously negelects lots of important aerodynamic effects..such as Boundary layer etc..)

The Real Reason why most folk fit these ITB's of course is to look and sound cool..MFI is uber-cool in the Porche Fashion stakes just now..

If all you want is ITB, for EFI, and a big intake, bore out a pair of old Zeniths..much more meat and cheap...

Kind regards
David

1972_911t · Post by **1972_911t** » Fri Oct 06, 2006 9:40 am

Hi David

Henry from supertec says he can get the mag intake stacks to 52mm, and the throttle bodies to 41.5mm at the bottom with a 44mm butterfly as he says there wouldnt be much point going bigger than this because ultimately your limited by the 41.5mm port and 49mm valve.

Back to the drawing board!

Steve

Mike Usiskin · Post by **Mike Usiskin** » Sat Oct 07, 2006 8:07 pm

HI David,

"The Real Reason why most folk fit these ITB's of course is to look and sound cool..MFI is uber-cool in the Porche Fashion stakes just now.. "

Why So?

regards

Mike