Originally Posted by 92TurboTona
is there anything wrong with running a TBI
cam in his setup
The biggest reason Shadows setup works with a cam is the intake and exhaust / turbo. He has nearly no pressure differental to speak of and his intake has a big plenum and shorter bigger runners that piles boost on the intake valve. The best conditions to use a big cam, he caan no doubt go bigger than the F4. The Crane springs I would bet are a quality coil and have a tad more pressure than listed. Then even though you lose lift, you still see the RPM and gain from more duration, the same reason the TBI
In this case I would wonder, is your conditions the same as Shadow's?
I see you have a header and a smaller turbo, which will help a lot. But what I also see is something that will murder the cams flow and the heads flow, a 1 piece intake. Unless cut up and rewelded bigger, shorter and smoother the 1 piece murders flow. It can't be "ported" to change anything either, it has to be cut up. Then 2 piece how ever really responds to porting.
So from the photo's I've seen, I would run the better valve train for now with a TBI
and play with advancing it 4 degree's. Not run the F4 yet. Once you get a better intake, then get the bigger cam. Even then I would look at the F2 without that bigger turbo. Kind of like building a V8 where you size everything for the same RPM level. A T3 turbo is a lower RPM turbo, the 1 piece is an off idle intake. So a stock cam will work in the right power range of the parts. A bigger turbo and a plenum intake will be a top end and mid range setup, needing a good mid range to top end cam, Shadow's setup. People with our intakes over time have been paranoid of cams. Based off RPM design Shadow's cam is conservitive in his setup but in the range. In this case with this setup we see in your tube header thread, your engine doesn't run in high RPM. So a bigger cam should hurt power at different RPM levels.
Keep in mind that a stock G head actually out flows the 1 piece and the 1 piece ported still hinders a stock G head pretty bad. So adding porting or valves doesn't increase flow much. The exhaust flow on the exhaust is cleaning out the cylinders though better. So you'll see some gain there, but the intake has to go to at least a completely ported 2 piece to use the new head. Or start cutting, which in your case is the best route.