whatsup1287

I'm getting ready to start buying parts for my winter project. My signature is up to date as of now.
I'm looking to do twins and I'm hoping I can use my Super B Special (64/71/14) as a top turbo and run a S400 under it. I do tow my Jeep around, (about 6000lb including trailer) and occasionally might be towing a skid steer.

I will also be porting the head, fire ringing the head with studs. 60lb valve springs, titanium retainers, 4000 or 5000 gsk, Cam, delivery valves,and a fluiddampr.

My question is, is the Super B Special (64/71/14) going to be to big as a top turbo?

Mike D

Yes, spool up will be a tad slower than it is now. You'll probably have to mess with your timing to find the sweet spot, probably around 20-22* depending on your injectors.

I've had no issues towing with my setup but I have a 24 valve.

whatsup1287

Thanks, that is what I wanted to hear. I figured I was going to have to mess with timing, I was going to start at 20* and work up from there. I was hoping that with the cam, and some porting I could keep the EGTs reasonable. If not, I guess I might have to look into water/meth to keep them down.

Jetpilot

A better match for a s400 would be a 62mm turbo. The 64 while nice will spool slower especially on a 12v compared to a 24v or CR engine. Also for towing keeping a smaller turbo as the secondary really helps on egts! The trick is in the combination, a 64 is better suited for something in the s480 range.

Doug

BigErksG2

I would go smaller than a 62 for towing on the secondary, maybe a 60/65/12 or 14 with a 76mm turbo under it. I have a hx35 over a 76mm 3b with the 26 housing and I cant complain one bit. Holds 40psi up a mountain towing and just under 1200 egts in OD.

whatsup1287

My old truck had a stock hx-35 with a ht3b under it and it would get warm up top. That was with 370 injectors and stock DVs. So I know I want to go bigger than a hx-35 up top plus I'm looking for more top end. I'm going to be running bigger injectors, I'm going to start out with the 435s I have now, and prob go up from there shortly after, along with DV's. I'm less worried about spool up and more worried about EGTs, but if I have to watch the gauge while towing a bit that's not a big deal, I have to do that as is.

BigErksG2

maybe a 62/65 or 68 from ED/14 on top with an s480 under it.