HI, I am rebuilding my lt1 as a 383. I would like to run a 175-200 shot of nitrous at the track. I have not decided on a set of pistons yet. So far I have an eagle 4340 forged 3.75 stroke crank, eagle 4340 5.7 H-beam rods and a set of milodon 4 bolt splayed caps. I have a set of ported lt1 heads with 2.0 int and 1.56 ext valves. I have a hot cam but am condsidering switching to a comp cam. I run open headers at the track and want the power band to range from 2000-6000. I run 110 race gas at the track and 94 on the street. I want a good set of pistons. I was looking at a set of JE's. I was guessing around a 10.5 to 1 compresion ratio. Any advice on a nitrous friendly compression ratio, rings, and piston brand is apreciated. Is the hot cam and springs a waste of time? Are the xfi cams a better choice? I am looking for 11.0's and hopefully 122 or so in the quarter. thanks

 

JE doesn't make a flat-top nitrous piston. With the size of the CC of a stock LT1 head, you'd be looking at around 13.5:1 with a domed JE piston. SRP pistons are NOT made for nitrous. Ross has a very nice flat-top nitrous piston, which is what I'm using in my new 355. With my zero decked 355 with a .035" gasket, and 54CC head, I'm looking at close to 12:1.

I went with Sealed Power file fit moly rings, with .024" top gap and .026" 2nd gap.

I can't see the Hotcam being enough for your combination. I went with the GM 847.

Frank

 

JE can make any type of piston you want.....I got a custom set of -16cc forged 2618 alloy pistons made with nitrous pins. They are about $900. I told the several techs i talk to at JE that worst case I wanted to do a 100 shot out of the hole, 150 shot after the 60', and boosting about 20psi through a supercharger. This is what they recommended

 

Im running wisecos here. Several bottles through the engine with a few lean expierences, stil kicking.