Numbers in sig, i'm wanting to go with 2.5" TDs for clearance and noise with magnaflow 4x9s. My quesiton is will 2.5" rob very much, if any power over 3" on my setup?

 

well by the looks of things your making 447hp? if so 2.5" duels will be more than enough. you will not be robbed any power untill you start making about 500 hp. is that 3" a single?

 

2.5" is enough for 500 hp it seems.......I am gonna change out my stupid 3" Y-Pipe for maybe even 2"......into 3" over axle........I don't go racin' everyone in sight with this car. So sick of hitting every damn bump and crack.[lowered 1-1/2"]

 

3"

 

I have had both of them, and had a similar setup on the last motor and found that the 2.5 made more torque and about the same horse and the 3 inch did, don't kill your ground clearance for nothing...

 

2.5 is plenty.

 

 

If I were to do mine again I would use 2.5 inch, and dual 2.5 inch pipes is plenty enough for 500+HP.

 

 

You're probably on the higher end of what 2.5" duals will support, but I too think that it will be enough. By the looks of your sig, you're lowered enough that 3" would be a major clearance issue with 4x9 magnaflows.

 

yeah go with 2.5"!! You will make more torque with 2.5.

 

I would go 3" personally but thats just .02

 

I am so sick and tired of my LM and catted Y. I really want to go with some 2.5 true duals out the back. If I supplied my own mufflers, x pipe, tips, and possibly cats, how much do you think it would cost to have something fabbed up out the back with some wingnuts on a flange at the axle?

 

if youre sub 500 i would do 2.5's. However a competant exhaust fabricator should be able to make a 3 inch system tuck. I fabbed a system that was 3inch on a friends h/c car. He was lowered with a pro kit and never scrapped his exhaust ever.

 

i am very sub $500. I was hoping someone would say the parts and labor (minus the mufflers, x, and tips) would be sub $250.

 

what might be the cheapest and smallest mufflers to go with?

 

sub 500 Hp lol. You could do duals for 500 bucks easily.

 

whats the point, other than to go with 2.5", if it cant be done cheaper than TSP?

 

sorry. I understand now, lol. Yeah, i had 2.5s on a H/C big block pontiac. Just fine. What kind of price do you think i should look for?

 

I like 2.5" because it holds a good amount power and it gives better clearance if your lowered.