I'm about half way through my h/c swap on my 99 SS M6. Along with the H/C I had previously installed a Fast 92 intake and 92 NW TB along with 1 7/8 TSP long tubes. I'm grinding through this and wondering how much different the car will feel with the heads and cam compared to when I did the intake and headers. The heads I'm putting on are PRC 225 with hollow stems and the cam is a TSP 228/232 on 112 and all the supporting stuff such as injectors, oil pump, pushrods, and rockers with trunnion upgrades. This is a bit of a chore in a small single stall garage working from the floor with my legs hanging outside in the Iowa winters and I guess I'm just excited to get to the end. As I lay under it working I cant help but be curious on what to expect and what the SOP difference will be. My previous car was a stock 15 2SS/RS Camaro M6 and I loved it but it actually felt a bit slow. I guess I'm excited since I bolted up the pan and timing chain cover and I can see the finished product is getting closer. Just wanted to hear if its going to be a huge *** change or what to expect on the street. I'm hoping to be in the 430-450 rwhp range but we will see come dyno day. Thanks in advance for any motivation and responses!

 

I definitely expect that you will need to change the tune in your PCM to maximize performance and minimize the chance of melting a piston. While I would attempt to start the engine if I was you, with so many changes, I would not drive it or run it very much until somebody looks at your tune for possible extreme lean and hot conditions.

Rick

 

I'm about to throw on TSP longtubes with catted y-pipe with Fast 92 intake and TB and was wondering if you felt a difference with just those mods? Also did you have to tune it after those mods?

 

I did the same mods minus the intake. I can tell you you will definitely feel the added power. You can feel it pull more 5k rpms and up untuned. I would definitely get a tune after you do the intake and longtubes. You will be satisfied with the added power