Projectcam94

My motor blew 3 days ago. So im planning on building a 355 motor. I want it to handle a 300 shot of nitrous. Ill only be spraying 250 but just incase. My question is can i use a stock crank? And just buy forged pistons/rods ?

Also any brands you all recommend ? Not expensive ones....

Ray@NitroDaves

For upwards of a 300 shot I would not run a stock crank....for a shot of that size I would not cut any corners in the shortblock. It will cost less to build it now, than to rebuild it if/when it breaks

rskrause

The weak link in a nitrous motor is usually the pistons. Take a look at my writeup on nitorus motors - it may be of help.

http://www.kennedysdynotune.com/Nitr...ech%20Tips.htm

Rich

Projectcam94

Nice Thanks

rskrause

A little more about pistons, the weakest link. As I wrote on the linked pages, you need to strongly consider a "nitrous" piston for a shot over ~150hp. They should be forged of 2618 or a similar low silicon alloy. In general they need to be "heavy duty" with a thicker crown, strong pin boss and NOT use lightweight pins. Exotic pin upgrades are not needed for what are talking about here, just avoid the lightweight ones. And most important, the top ringland needs to be in the range ~0.20-25" or more in thickness. Unfortunately, there is no cheap piston that will stand up to a 250hp nitrous shot. Expect to pay in the $550-700 range, or more. Ross has a line of "heavy duty" flat tops that are listed as suitable for up to a 250hp shot. They run around $600, a very good price for what you are getting, IMHO. The Callies Compstar is a very nice rod for ~$550 and the Compstar crank goes for about $600. Figure ~$2,000 for the rotating assy. with rings and bearings. Them's the parts I would get, if you have to cheap it out more DO NOT compromise on the pistons.

Rich

slomarao

On the list of the fastest LT1's there is a guy with a 300 shot on a stock crank. Would i do it? Hell no, can it be done, absolutely.

With any hit above 200hp i would go all forged, 4 bolt, yada yada yada. With Rich on this one. Make sure the pistons are top notch, the rest of the shortblock should be forged but its all up to you. Pick a quality piston. Good luck