Hey everyone i was wondering what kind of setup i would have to have to be able to run from 250-400hp Nos kit on a "stock" 350/400? i dont want to put alot of money into this but i want to be able to build the bottom end to it could hold such a high hp kit. anyone have any suggestions?

 

I run a 250 shot on my 350,4bolt main and studded motor. Its a weekend cruiser so not many miles on it , held up for 2 years of street racing. Have good fuel system with 2 electric pumps and regulators as well as MSD with retard. I think over 250HP on a smallblock is pushing it a bit.
I have run a 275HP kit on a 305 with only forged pistons,studs and rod bolts ,held up for 1 season. The crank and rods and bearings were fine upon teardown but the valvetrain was shot from high rpm-s (not directly caused by NOS) . I have a friend who runs a 300 shot on a LT1 which is basically stock internally. Can not expect that motor to last forever tho. Anything over this amount is very risky in my opinion and You really have to know what You are doing at 400. At that level (I personally would not try that) Your next race could be Your last run on the motor...

 

I forgot to say that the 350 with the 250 shot has all forged internals. I think Your motor should have forged internals also if You expect it to last some time.

 

i have a 305 but i can get a 400 (choice of 2 and a 4 bolt)or a 350 but i want to build up the motor and everything needed for about 1500. not sure if its possible but i want to be able to run 11/12 range with it. thanks for all the info your giving me!

 

The key place to put the money is the pistons. Forged. A weaker crank and rods may hold up to that kind of a shot but the pistons will go bad really quick.

 

Well,if the $1500 means the entire budget for NOS kit+MSD with retard etc.
then it does not leave much cash for fancy forged rotating assembly so I would also go with what Dankhound says,forged pistons and studs+rodbolts+good oiling .
Just a basic engine. If the tune is good and You stay out of extreme rpm-s it should be OK for a while with a 300 shot
(the most I would try to run). With that much NOS if You have good head flow and a decent cam and the rest of the car working properly You should be able to run around mid to high 11-s. Not gonna last forever tho,but in Your case it is no big loss if You blow a motor, it will not be a big loss since it was a low budget build to start with. It will survive if You stay out of detonation. And try to keep CR low, around 9:1...

 

Alright, then im staying away from the 400hp setup, i was thinking of the dual stage setup. for over 600, it goes from 100/200 100/250 125/325 150/375 and 175/400. what setup would you guys think would be best for my situation? or am i going in the right direction with the one above(Nitrous Works 12065)

 

This would depend lergely on traction at launch,or more likely,lack thereof...What I would do is start with the lowest setting of one stage of 100HP shot and see what kind of traction I can get with this shot. If You have good traction (slicks) and the car hooks decent with the lower level then
You can add a bit until launch gets worse.
This way You find out what the max level is for first stage...once You have that worked out, You can start playing with stage 2, and push the rest in the second stage. Dual stage setups are nice because they allow to adjust power delivery to traction better then single stage systems. I think You will end up with something like the 125/325 level for racing
on the track. You will need racing gas tho...and keep an eye on Your plugs. You will prob. need R43TS plugs or something in that heat range...

 

Im leaning tward this being not too possible with 1500, i think the amount should be more like $2k for this to go bare minimum. i like the idea of the 2 stage system as well for the same reason, but chances are ill be going through motors like crazy if i dont get the setup right the first time lol!

 

You are correct... the 2 grand would prob. only pay for the NOS setup+ignition+ timing box and maybee fueling at this power level. And You still need a motor...figure at least a $1000 for the motor with just the absolute basic stuff discussed above... and doing most work Yourself...

 

i can do all the work myself besides the obvious machine work but still, im gonna figure it out and see how much it all costs in a little bit and see what i have to work with.