I have run this cam through the computer sim and it shows max hp of 259 at 4000 and max torque of 382 at 3000. Isky designed this cam back in the 80's for a max torque 350 in a race car hauler. They just can't deal very well with big cams unless you start turning off certain feedback features in the lower RPMs to 'force' a drivable tune there. A big lumpy cam, a MAP sensor (which isn't even used to build a real air density table in the ECM table) and a narrow band O2 sensor don't play nice together. But it ain't the EFI system you go racing with. Not a problem if you keep the combo relatively modest. There is only so much you can do with them. Remember that the TBI computer system of that vintage is only 1 step up from the old computer controlled QJet systems of the early 80s. Makes tuning the stock system much easier, even with a custom tune. So MATCH the cam to the RPM range the heads are capable of supporting and you can make bigtime torque in a usable RPM range.Īnd, like was said above, keep the LSA rather wide- 112* or wider. No, it's not going to scream on the top end, but nothing can help those heads once the tach swings much past 4500-5000. 050 on the intake side) and will belt out low-midrange torque like nobody's business. 050 would actually be pretty big compared to the stock cam (which is 191*. An old school single pattern cam of mild duration, or a cam with only a mild split between intake and exhaust druation will actually work quite well for that reason. What I'm saying is that the swirlie heads actually have an excellent Intake/Exhaust flow ratio- around 75% or higher, even though the overall flow potential is not very high. First off, the TBI heads have a pretty bad intake port (swirl port) but a fairly decent exhaust port (ever bit the equal of Vortec heads, much better than non-swirl-port heads of the same vintage). If you have to go flat tappet, I'd make a few suggestions. You can even use the stock springs with them up to about 5000 RPMs. If you can go roller with the block, definitely consider a used LT1 roller cam.

Iskenderian roller cams for chevy 350