I Have The Hy35-9 In My Truck According To All I Have Read (auto Trans). What Is The Difference In Performance Between The Hy35-9 & The Hy35-12? Also Will The 35-12 Fit In Place Of My -9 Without
Modifications? Or Would The Small Increas Be A Waste Of Money?
I Am Running The Ez Module And Modified The Wastegate So It
Doesn't Open. I Can Feel The Big Difference Over The Stock Performance But Would Like To Go A Little More. According To
Edge This Should Put Me Close To 300hp And 640 On Torque.
Thanks Tb

 

Yes, you have a HY with a 9 cm exhauset housing. The 12 cm housing would be bigger, slightly slower spool, but lower EGTs.

I can't imagine you having EGT problems wiht just an EZ, so I would say stick with what you have. If you need to later, you can swap just the housing.

 

Agree with the above. With just an ez you shouldnt need it unless you plan on adding more power. I ran an ez and rv 275's on my hy without any real problem even here at elevation but rarely towed over 5k. After I added the catcher or now the smarty the hy wasnt up to the task. I then upgraded to a piers hx35 and it was good to go. However I do not think the 12cm housing from an hx35 will work with an hy35. The connect differently if I recall.

 

No real change in performance or egts will be seen. The HY wastegate is adequate to flow the exhaust fine..... We didi this swap years ago on several trucks and the dyno and road testing proved this. The HY was installed on our trucks for emissions reasons not performance reasons.

Doug Smith