Superado

iTrader: (34)

I was told that it was an odd-ball 3.75" instead of 3.0, 3.5 or 4.0...

I know it's less than 4.0", the guy that fabbed my inlet to TB said it was 3.75", my ProCharger layout diagram shows it as 3.5"

T/A KID

iTrader: (12)

3.5 on each side

Superado

iTrader: (34)

Thanks! Need to order new couplers...

kbracing96

iTrader: (25)

I hate to disagree, but if its a 85mm truck MAF (looking at sig) Then it about 3 3/4 on one side and 3 7/8 on the other, but 3 3/4 will fit over it. I used 3 3/4 couplers on the last turbo setup I built.

ninetres

iTrader: (35)

What size coupler should I use for the stock LS1 TB......4"?

kbracing96

iTrader: (25)

Ya, the throttle body is 4"

Superado

iTrader: (34)

Thanks kb...
So a 4" to 3.75" coupler should work on the TB side...I have a 4" inlet tube from MAF to TB and we used a piece of hose to make a bushing to be able to use a 4" ID piece of hose as a coupler...the ATI coupler is still on the other side (3.5" I/C side to 4" MAF side)...if I decide to replace it with silicone as well, a 3.5" to 4" should seal to the odd size on the I/C side as well as or better than the black rubber one supplied by ATI, right?
Thanks guys...