I just got a set of aluminum truck heads. Unmilled, my compression will be at 9.5:1. My ultimate goals are to spray around a 200 shot on my heads cam car. If I leave the heads unmilled, can I do this without race gas? What kind of compression is recommended for a 200 shot on a street car?

 

Are these 6.0 heads? Nitrous likes compression. I'm running a 200 shot with 11:3:1.

 

on pump gas?

 

Agree, although just having compression isnt the ticket, the cam has to have the right events and timing to utilize the cylinder pressures, and not exceed or bleed-off, and lots of other ****. I personally wouldnt spray 200 on pump gas, even on 8:1 compression. Just kind of not so good feeling come to mind. I have however ran 175 on straight 92 Octane pump gas, lowered timing and on the richer side than normal jetting, but I wont do it anymore after looking at the plugs!
Safe to mix in some race gas when using the 200 shots.

 

That's the plan, but we'll make sure the tuner thinks it's ok first. There are a few cars around here running 175 on 12:1 in LT-1's. With a good nitrous tune it should be ok. If the nitrous tune tends to kill my N/A number, I'm gunna jet down because I'll be N/A alot more than on the gas.

 

Well, why not have both tunes change at the track? Good luck.

 

It all really depends... Is this a street car or a strip car... Bottom end stock or aftermarket...If its a street vehichle its simple 9.5:1 is the way to go. If its gonna be a strip car and you dont mind race gas prices you may wanna bump it to that 11:1 mark. Personally I am a low compression fan my self.

 

According to Chris @ AP Engineering, 91 octane is good for 11:1.

 

I will be running 93 octane in mine with 11:5:1 in my lt1 NA and will either run race gas in the tank or have a seperate cell for the 200 shot however for the 150 shot I will probably just pull some timing or mix in some 100 with my 93 and pull a degree or two.... I am runing a comp 236/245 .569/.580 on a tighter 114 lsashould do well na and on the love juice