I just got an email from jon whos running the GP on SLP headers and he said the pipes to the cats get as small as 2"!!! the rest of the time they are 2.25"...is this cool, I was hoping for 2.5"??
Thanks,
I 'm having a hard time deciding on headers, I thought I had it figured out and now I'm in a dillemma again.

 

On the SLP dual-cat system, the pipe is 2.25" until the end where it is close to 2" to match the diameter of the cat. If you keep the 2" cats, the headers aren't going to be a problem. I cut mine back to the 2.25" section and put in a Flowmaster Y-pipe to connect the two pipes to my four inch. SLP assured me that their system will support 500-600 horsepower. The quality is great and they were relatively easy to install. I had to clearance mine for the steering shaft. No big deal.

------------------
1992 Camaro Z28; Engine:383 w/Ported Edelbrock RPM heads. Lunati Solid Roller Cam 224/232 .502/.502, Fluidampr, Comp Cams 1.5 Roller rockers and lifters, Comp Cams Triple Valvesprings, SVO 30 lb injectors. Holley/Walro 255 lph in-tank pump, Haltech E6GM DFI, SLP 1 3/4" headers, 4" Mufflex, T56, 4.10. Super Ram. 17" X 9.5" Ronal FireHawk Rims w/ 275 40ZR17 Bridgestone RE 730's up front and Nitto Drag NT 555R's out back.

Double-Pump This! EFI Rules!

 

alright thats cool, thanks