I've been trying to sell the car, and haven't had any luck, so it looks like I'm just going to have to go all the way and finish it off and keep it for eternity. The motor that I just put into the car, according to my buddy's desktop dynow program is pushing close to 500 hp. Under my car are a set of Alston SFC's that I installed years ago, and a spohn crossmember mount torque arm, both of which get in the way of true duals. The oil pan I let my buddy talk me into using is a 7-quart Moroso with a square cut front and wide kickouts on the sides. The exhaust currently consists of the 1.5" primary, 2.5" collector Flowtech coated shorties, a y-pipe that I had a local shop fab up to fit around the oil pan that the guy made fit nicely, but doesn't flow like I want it to, and the good ol stock 2.25" I-pipe with a flowmaster 80 series welded in the back. With open headers, this sounds mean as hell and is absolutely insane. The exhaust is really holding this thing back. I was considering buying the SLP loud mouth II kit, as it looks like the best flowing 3 inch kit available. I listened to some mufflex clips, and just don't like the sound of it. I'm also considering the magnaflow LS1 kit. So, If I do that for the back half, that will be considerably better than it is now. What can I do to the front end. There is about 2 or 2.25 inches between the front of the oil pan and the crossmember. The tranny is an automatic, so I don't really have any room behind the engine. If I get some SLP 1.75" shorties and an SLP y-pipe, will I be able to hack the y-pipe up a little to make it fit? (I've never seen one in person before, only pics) Also, will all of the work that takes be worth it? The y-pipe now consists of a 2.25" pipe from the driver side that runs into a 2.5" pipe from the passenger side. The guy didn't have room or a mandrel bender to run two pipes and run them into a y-collector, so he cut an opening in the side of the passenger leg, and ran the driver leg straight into it. Please, somebody give me some guidance. I have had three different people look at it, and duals are not possible. The exhaust will only fit in the stock location. I don't care if I have split exit duals, 2otl, or single exit. I want it to perform most of all, but I also want a nice tone, not something like my flowmaster sounds. What should I do?

Thanks,
Eric

 

You are really killing that motor using the Flowtech 1 1/2 primaries, you need larger headers first and for most.

 

4 inch single with the muffler of your choice.

 

Slp 1 3/4" shorties if you want ground clearance, with custom 2 1/2 or 3" y pipe or for longtubes, hooker 1 3/4". With 500 hp you need a 3 1/2" or 4" intermediate pipe into a single in single out dynomax or magnaflow muffler.

 

My problem with the y-pipe is making it fit without hanging down 3" below the oil pan. Also, where do I get a 3.5 or 4" I-pipe? Is it possible just to get an intermediate pipe without the rest of the catback? Also, I've been told that Spintech makes some kind of 5" oval pipe; has anybody ever seen it?

Thanks,
Eric

 

MUFFLEX sells dual 3" into 4" y-pipe...also 4" exhaust

 

Sportsman 2's and 1 1/2" primaries aren't going to get you 500 horsepower.

 

Yeah, I know this exhaust is killing me, I just need to find a way to make the y-pipe fit. The donor car this engine came from had Hooker 2210's with no exhaust on it. I drove that car a little before I yanked the motor, and I can tell you, that 500hp estimate is probably not far from the truth. No LS1 car I've driven could touch that thing. I can buy bigger headers and a big cat back, but getting the headers hooked up to the catback in a good manner is the real challenge here. My Alston SFC's keep me from using long tubes and a mufflex y-pipe. I think SLP's are the only/best way I can go. I just need to search to try and find pics of an SLP y-pipe installed so I can see how it fits in order to know if I will be able to modify it to make it fit around my oil pan.

Thanks,
Eric