2.9 Whipple Rear-Feed Questions.

[The Red Monster]

I am in the process of making the jump from a 2.3 whipple to a rear-feed 2.9.

What pulley size are you guys running on stock short block?

Also I am currently running a 3.0 pulley on my 2.3 but I am in the Las Vegas valley so elevation has allowed this. What would be a comparable pulley size with the 2.9? This one includes both 3.750 and 3.500 inch pulleys.

I have a SAI LI fuel system installed and plan to build the short block here pretty soon. What are the max power #'s you guys have seen from the rear feed 2.9's?

Thanks

 

[The Red Monster]

No one has a rear feed 2.9 whipple that can shed some light on this?

 

[philkilla]

I've been running a 3.750" pulley on my rear feed for a while now.

 

[stangn]

Every combo is a bit different of coarse. Mine had VMP 15 o/o 8 rib lower and 3.5 upper “I think”. Built motor, JLT big air, twin 65mm TB, CJ exhaust cams, 1 7/8 shorties off road X and GT500’s. Think it was 12-13 psig. Just changing mufflers on my car changed boost pressure, so for what it’s worth.....

 

[1 Alibi 2]

The stock pulley on my 2.9 was 3.00.
On my 2011, 5.4L, it made 776rw / 679tq / boost was 19.4, with several supporting mods, stock bottom end......( not a canned tune )

 

[The Red Monster]

Looks great!