pics coming soon

 

what if you went 3.5" off the collector into a 4" merge then 4" cutout then into whatever catback on bigger cube 402+? would going from a 3" to a 4" have better scavanging?

 

Depending on header choice, camshaft, valve sizes, and power band. I mean a 403ci 600rwhp motor would like that but it would loose torque on the bottom end. The idea behind the y pipe is to create a positive flow design until it opens into a larger pipe causing a flow characteristic change. remember exhaust likes some piping to flow thru, most exhaust systems 18-26 inches past the headers create more power than most open header designs.

what are building in reference to the 402?

 

I had the Mufflex 4 inch system installed by them at their shop. IT SUCKED. Some here have had good results with Mufflex systems, some have not. It hit everything, the top of the rear, the floorboards, the universal joint...Mine even fell off the hangers they made up for them.

Seriously, unless you’re running like 800HP, 4 inch is overkill. 3.5 should be plenty. Stainless Works makes a very nice 3.5 inch system that installs well. Seen it, heard it, loved it. One day....

https://ls1tech.com/forums/12081612-post22.html

 

I'm sorry to hear you had a bad experience with Mufflex. With every shop they'll have unhappy customers.

The Stainless Works system is very nice but it's around $800 just for the catback! I recently installed a Stainless Works system on my friends Trailblazer SS, it was great quality and everything fit fine. Sounds very good too.

 

well to tell you guys the truth i was playing with getting duels for a while and also playing with getting a 3.5 or 4" system...but im not doing either. Right now i have hooker headers with there y pipe into a 3" magnaflow catback system. I also have an extra magnaflow bullet style muffler in the exhaust. it sounds great and puts down over 500 to the wheels. only thing im going to do is put duel cut outs behind the first bends in the y pipe on either side. You dont need scavaging or back pressure at the strip

 

LOL very true but remember opened headers is not always the best for power. what is your setup that you are 500rwhp?

 

4" and dont look back, IMO.
just dont run a slowdisaster or a spincrap muffler.

 

Ya i know its not always best for power but its cheaper and easier then changing your whole exhaust.

I have a forged 347 built for a huge shot, F13 cam, completely stock 241s, 150 dry shot right now through a 12 bolt

its actually a bit over 500 but im looking to go with a direct port next season. its over 400 NA and i will try and get her to over 600rwhp with out having to change the heads

 

OOOOO. I thought you were saying 500NA and was curious about yoursetup. Yah my non forged 346 with a 150 shot made 608rwhp so your goals are very duable. But I gained power going to my 4" while changing to a 9" moser rear.

 

ya i dont need to go faster then high 9s and a touch over 6 should be there

 

I hate being in the high desert and not at a decent track. You plan on running 9's with 600rwhp and I could only get a 10.7 lol with 608rwhp. I need to finally put my auto tranni in so I dont keep destroying clutches.

Good luck on the single digit pursuit.