Hi all. Switching from nitrous to turbo. Here is the combo.

340. Spare motor. Been stored a while. If I blow it up it's not a big loss
Forged pistons about 10 to 1 compression and steel crank
Cast J heads somewhat ported. 2.02 valves
s480 turbo with 99 ram manifolds, tial mvs waste gates
Blow thru carb by Horsepower Innovations on E85

My question is the camshaft. In it now is the MP .509 lift, 292 duration cam with 108 lobe separation. From what I have learned from searching is turbos need a 114 lobe separation. The only off the shelf cams I have found so far with 112 or 114 LS are from Jegs and the 112 LS cam says it is for 2000 to 4500 rpm. It is a NA cam but will it work better than what I have now?

http://www.jegs.com/i/JEGS-Performance-P...9634+4294828937

what exhaust housing on the turbo?

These days if you have a turbo that isn't restrictive on size the cam recommendations aren't far off the NA motor. If you have small, street sized turbos like I do that build substantial back pressure, then it can matter.

A shelf cam may work better than what you have but the extra 200$ for a custom cam will save you a bunch in testing and worry!Good luck on getting as much info as you can.

Comp will have you a custom grind in 3 days . They did my turbo cam. Been happy with it .

The casting numbers on the exhaust housing are 671696 132 472. If my research is correct it is a 1.32 exhaust housing. Does that help?

Yeah the 1.32 housing, T6, 96mm turbine is the common s480. That little 340 will need a bit of work to get that turbo lit. When my 367" had the wrong (tight) converter in it, it would take over 10 seconds to spool from an idle. But once it gets to 5psi, it'll go to 20psi in less then 1 second.

The 340 is going in as a starter motor to let us learn about tuning a turbo motor while the 408 stroker with Brodix heads is being built. The plan is to foot brake it with a small nitrous shot to get it spooled.

Comp states right on their website that they don't charge extra for grinding a custom cam as long as the lobes come from their catalog, which contains nearly every lobe known to man! Bullet will grind a custom cam for not a whole lot, and they'll consult with you to get something that works pretty well.

I'm sure there are others. It shouldn't cost $200 more to get a cam ground the way you want it, as long as you use one or two of the grinder's lobes. I'd imagine you could expect to pay list price, though. Also there are Board members who consult in these instances and get you a custom cam. I'm sure they'd be reasonable as to charges for the consulting.

R.