View Full Version : proper silicone diameter to fit over OEM 90mm DBW throttle body?


NOS327
04-18-2012, 10:53 AM
I did some searching, lot of rif raf. If I have a stock 90mm DBW throttle body, what size of silicone adapter do I need? Seems like 4.25" is the answer, but some say a heated/slitted 4".

Firm answer would be appreciated.
TJ

NOS327
04-18-2012, 01:06 PM
Woops.. should be in external engine forum. Maybe a mod can move this thread

Darkman
04-18-2012, 09:16 PM
For what it is worth the GM seal/gasket is part number 12576549 and is Felpro number 61436.

NOS327
04-18-2012, 11:02 PM
No. I mean a silicone hose/elbow that would mate your air inlet duct to the throttle body. Not the tb to intake o-ring.

Darkman
04-19-2012, 06:19 AM
No. I mean a silicone hose/elbow that would mate your air inlet duct to the throttle body. Not the tb to intake o-ring.

Sorry, my bad - I saw the word silicone and was thinking silicone seal. In any event the answer is 4.0 inches. I am running a 90mm LS2 DRW and it measures 3.960 at the inlet, which includes a slight lip. (This is the same as my stock LS6 DBW 78mm throttle body which allowed me to use the same inlet air tube when I upgraded.)

NOS327
04-19-2012, 05:23 PM
Awesome, thanks!