ncd1966

iTrader: (2)

I am currently working on my dads camaro and we just finished up the stand alone fuel cell for the nitrous. the motor is a 383 ci with a SCAT "9000" Nodular 3.750 Stroke, Lightweight, Knife-Edged Crank; Triton Engineering 4340 6.000 H-Beam Rods; JE/SRP Dished Forged Lightweight Pistons; Milodon 4-bolt Splayed Main bearing caps; Vortec ported and polished heads with Stainless Steel Ferrea 2.02/ 1.60 valves and its 9.5 to 1 compression. and the entire engine has ARP studs no bolts. so its build to take alot of nitrous
The stand alone fuel cell has 114 in it and we are running 93 to the carb.

we have a 100 shot on the car now the timing is set at 36 degrees @ 3000 rpm. I was wondering if that would be safe to run as is right now for some street test runs?

and then maybe set it at 32 degrees to run a 175 shot.

I'm know a little about nitrous but we have never sprayed the car yet so I guess I just want to be safe instead of messing up this built motor.


thanks

moge11

well thats probably too much on motor with the vortec heads. They generally only like about 32 degrees. 34 max.

ZONES89RS

iTrader: (25)

Man, be carefule, you should be fine but my machine shop has me not wanting to spray my 383 i am building, i have the SAME crank as you and the machine shop told me that it is a BS crank really and stockers have usually out done them, now that i am out of money for the build to get a forged crank...go figgure.

ncd1966

iTrader: (2)

oh wait I told you guys the wrong crank it is a forged scat crank shaft my bad. I did not build this motor. but I know its all forged he spent enough money on the bottom end.

anyways I had the timing @ 32° before I decided to crank up the timing a while back and it woke up big time just 4 degrees advance. these vortec heads have a good bit of work done to them. I not sure what all been done but
the guy who built the motor ran it on a dyno and he said it liked alot of timing.

I'll guess I'll keep testing it to see where the sweet spot is.

ZONES89RS

iTrader: (25)

That is what you have to do, you can build two identical motors and still they can each prefer different timing.

JTM

I was about to say why a scat 9000(cast) crank with h-beams and forged pistons? lol. I have run a scat 9000 low 11's on motor, probably would have been fine with a 100-150 shot at least for a while.

RAGENZ28

iTrader: (5)

I would set it up so there is no more than 32* of timing at any point in the rpm range. Not sure if you meant you have full timing at 3,000, but I'd limit it to 32* timing, with timing and air fuel ration it is always better to pull more timing than you need and run it slightly rich. You won't make max power, but your motor will live much longer.

ZONES89RS

iTrader: (25)

Was that wit an automatice or stick?

1997bird

iTrader: (2)

GM crankshafts have a rolled radius, not a machined radius on the crank like the aftermarket cast cranks. A big part in how strong the crankshaft is, comes from having a larger/better radius on the crank as the journals blend back into the casting. The Scat 9000 cast steel crankshaft is modeled after the lightweight billet/forged cranks that Scat manufactures. Which means that the crankshaft has a larger raduis machined into the crankshaft, making it just as strong as a GM 1053/5140 forged crankshaft depending on the circumstances. The only way that I know of as the limiting factor to this would be in a race car getting large amounts of traction (10" full slick on a tacky track surface, road course race car with lots of traction getting on and off the throttle, or a circle track car in with a large tire on a tacky track).

Vortec355

I run 34 degrees tops with vortec heads and 29 degrees with a 125 shot. They don't really like a lot of timing because of the fast burn chamber.

ZONES89RS

iTrader: (25)

Good info man, thanks a ton bro.

krazy4

iTrader: (5)

The 114 Octane should help. I would say 30-31 degrees.

My dad runs a 150 shot on his 355 in a 67 camaro. He has all forged internals. The kit is from the early 80s lol. No purge, no bottle heater, no window switch, just the kit. Hauls enough *** without it. Spins the tires at 40mph without the spray.

This thing has lasted forever. He has had the car since he was 15. Forget what his timing is though lol.

JTM

TH400 w/tb and 4k stall

ZONES89RS

iTrader: (25)

Ok, i dont think a scat 9000 will take the hit of a stick with slicks as 97bird basically stated, if it goes mid 11s for some reason i will spray it but should go 11.0s give or take for me i believe.

ncd1966

iTrader: (2)

thanks for all the info guys. me and my dad went to do a 100 shot test run but the coolant temp was kinda hot. 190- 220° so we parked it back in the shop. we have a griffin 2 core radiator and a 160 stat with 2 black magic fans. that should be enough cooling

Well I will lower the timing hopefully today and see if it will fix the hot temp. I know the heads have alot of port work done so not sure if its the port work causing the temp or too much timing.

I'll have to post up some pics of the car and the nitrous setup for you guys

ncd1966

iTrader: (2)

what cam are you running with that setup?

RAGENZ28

iTrader: (5)

On the motor sometimes running too little timing will cause it to run hot also.

1 FMF

iTrader: (1)

http://www.msdignition.com/tool_8.htm

have you considered one of these?

Vortec355

248/258@.050 581/563 lift

ncd1966

iTrader: (2)

man thats alot of lift with a vortec


I tuned the timing to 32° and I found why the car was running so hot.

My dad had one fan pushin and one fan pulling

so now they both pull and its running cooler