is there a big power difference with a 3" downpipe? i know it helps both power and reliablity. i ordered a dp and mp combo for my car already but i want to know how much of a difference it will make. right now i dynoed 258 at 12psi. i think it is low because of that. i also have a greddy ic but am stepping up into an m2. looking to get 310 to the wheels at 12psi. also have the factory intake modded but am changing to hks.

 

I couldn't tell you what it does at the dyno, but I noticed big difference with my SS downpipe and highflow cat. Much quicker spool up on the primary turbo and quicker off the line.

 

I would say that your dyno numbers are low. I dynoed at 240 at stock boost with the stock IC. I do have Apex'i intakes, DP, and a Racing Beat dual tip CB. But I also have a small boost leak and I'm running ungodly rich!! You might wanna take a look at your numbers again. Just my .02 though.

Zach

 

You don't mention an ECU upgrade in your post. With a DP & MP added, you will blow your engine unless you upgrade your fuel computer.

My first upgrade was just a downpipe. It felt like a minor increase in HP.

Adam

 

Completely stock engine but for DP here. I found running fuel injection cleaner to give me more power across the rpm range than the DP did. I have glowing turbo sysndrome, so I have other issues right now.

What I DON'T have is that blast furnace effect when placing my face next to the ABD distribution block. Love to smell my engine, for some wierd reason...

 

slight hp increase but more importantly there is a great gain from releasing some of that under hood heat.

 

Plus, you will be able to hear those turbos working just a bit. Whistle, whistle.

And like others said, better spool up and less heat soak under the hood. It was my first mod too! Good choice. Be careful getting those studs out. Soak them with penatrating oil for a day before you try to remove them. Those suckers love to gawl!

Jeff

 

i have a petit ecu also. if it doesnt give much power why are my numbers so low?

 

The number i've always heard for 3" DPs is 20 hp. Flywheel. probably depends on what ELSE you have too.

 

with just a DP, there's a very slight drop in the low end, but a noticable increase in power in the top end... and, like others have said, you will be hearing a lot more from the turbos. With a DP *and* MP, you'll notice a huge drop in low end, but an equal gain in the top end - make sure you have a boost gauge if you install both & watch very closely for boost creep.

 

i also have a greddy ic, cat back, msd, pettit ecu, greddy boost control, water injection. well i am going to be putting both of them on soon and then ill dyno again. i hope it gets up the numbers

 

really really like my pettit downpipe. Huge difference, butt dyno approved, runs like a new car. Would have gone with the M2 but they are always back ordered. Found out too late that Shane at AIM keeps M2s in stock. Here's the link if you are looking:
http://aimtuning.com