Actually, LT's and any catback with a 3" intermediate pipe. I was looking to get the GMMG's, but know that some time I also want LT's. Heres my dilemma LT's normally have a 2 3" collector and then I would need to Y them together into 1 3" I-pipe.
Would going from 2 3" pipes into 1 3" pipe choke off the engine or, more or less negate any benifit the LT's added?

In other words would I be getting any benifit out of this setup?
Would I be loosing potential power?
Or, will this just give the back pressure needed for the system, or will it be too much back pressure?

Just wondering before I spend the money, if I need to I want to get something like the GMMG's but with a 4" I-pipe , even if I get it custom made at a local exhaust shop.

Thanks,

 

There is no way a 3inch ypipe or ipipe is going to choke off the longtubes. I ran Hooker longtubes, offroad 3 inch ypipe thru a cutout on a SLP 2OTL catback. I went from 272rwhp stock on my 97 SS to 301 rwhp after the longtubes and ypipe.The full 3inch piping should suffice for upwards of 425rwhp, then you can start to think about "needing" the 4inch piping.

 

That's exactly the kind of info I wanted. So, it's good to see you picked up almost 30rwhp from the LT's & Ypipe. Thanks!

How about any one else?