Originally Posted by 383silverado
or you can get a new 3.75 stroke scat 9000 1 piece rear main seal crank for 200 bucks.
That's the only way to fly as fas as I'm concerned. I was going to the adapter route, I already had a 2 Pc. rear main 383 crank and had a 1 pc. block but by the time you get your 400 crank turned down and buy the adapter you'll have WELL over the cost of new Scat crank in it. The adapters are in the neighborhood of $140 IIRC and then you still have the leaky 2 Pc. rear seal to deal with. You'll be money ahead to sell the 400 crank and buy a new 1 Pc. crank. I traded off my 2 Pc. crank and bought the Scat crank for mine and it is REALLY nice.
Originally Posted by 454C10
gm 383 crate engine with 196/207 degree roller cam and vortec heads, gm intake and 625 demon carb makes
338hp and 444 ftlb of torque ........... with a tiny, smooth idling cam.
That is the '395 Marine cam which is also used in the 350 Ramjet. Don't let the specs fool you it is a great little cam. I have been playing with it on DD2000 and with a set of AFR195 heads on the HT383 engine 454C10 listed above it showed 440 LbFt PLUS from 2,000 through 4,500 RPM and 404 HP at 5,500 RPM. This is an engine that would idle at 600 RPM like a sewing machine, pull hard to 5500 and and run on cat pee. I have been able to duplicate GM's dyno results for the HT383 on DD2000 within 5% so I'm pretty confident about the numbers I just posted. Swap in the ZZ4 cam and TQ drops to 403 at 2,000 but is 459 @ 4500 and HP is 448 at 5,500 and it still has a fairly smooth idle.
Mine goes to the machine shop in about 5 weeks. I'm using a Scat crank, 5.7 rods, 18cc D-cup pistons, Vortec heads and the ZZ4 cam. I was going to use the '395 cam and already have it but I decided I could give up the low end in exchange for a little more between 4,000 and 5,500. DD shows that combo making 383 HP @ 5,000 and 431 Lb Ft @ 4,000 with 398 LbFt at 2,000.
I'm still kicking around spending the bucks for the AFR's and sticking with the milder cam though. I'd pick up power all the way through the power band and I think I could be happy with those kind of numbers.