1999TransamWs6

iTrader: (21)

Im looking to do a 2 stage NOS set-up. It will be 75rwhp on a NOS 5177 kit backed up by a NX MAF kit with 150 rwhp. Everything in the car is modded ezcept for the bottom end. Will this hold up? We would be looking about 630rwhp on this set-up. What do you all think? As long as the AFR stays under 11.8:1 you think ill be safe? Any opinions please chime in.

383LQ4SS

iTrader: (33)

How are you going to control the activation points? Are retarding any timing? I think you should probably retard a bit when the larger second stage hits.

Or...if they are spaced out by RPM like say....75 on at 3000 and then the 150 comes in at 4900 you may be able to get away with close to full timing if you run some 104 unleaded.

I do fully believe that the bottom end will hold that shot for some time as long as detonation is kept COMPLETELY in check. Do whatever is necessary to ensure there is no detonation and should live barring any manufacturers defects of the pistons etc.

Things you can do to reduce detonation are...
space out the stages with rpm to keep the Tq peaks more avg
use race gas
reduce timing some
ensure you have plenty of fuel and keep AF around 11.5 to 1
Correct heat range plugs
ensure no contamination of oil through PCV

white2001s10

iTrader: (4)

I'm going to say the bottom end will last longer than the intake manifold.
Bottom ends have taken more than that, but you never know.

1999TransamWs6

iTrader: (21)

thats what i was thinking and yes i will run race fuel and have the stages come on according to rpm like 1 at 4000 (my stall) then when i shift second. thanks for the help.

Robert56

iTrader: (2)

yep, I agree, spread that torque out and you may or may not last for a while. The tune must be right on. A buddy hit 575rwhp and a ring land let go, but he was adding to much n2o to soon. Our stock lower ends can handle quite a bit, if we get some of it coming on in the higher rpms. The higher in the rpms we go the more nitrous the engine can handle. I will be trying the limits myself this next season.
Robert

Robert56

iTrader: (2)

That's funny.
Robert

GM Muscle

iTrader: (9)

Being that those are rwhp shot, your looking at well over a 250 shot at the crank. I wouldn't expect the bottom end to live very long. Like Robert said, I would try and put the bulk of the shot in the upper RMPs, however, the stock rod bolts probrably won't like that very much.

sprydncamd ta

iTrader: (4)

me and two buddys run 250 shots 2 of us have progressive controllers and one is a nos 5177 no jet shot 1st stage and second stage is a cold fusion 100 wet shot we all have cams headers and so on no problems here exept stock rears