Horsepowerfreaks Goliath?
 

Hey I'm thinking about getting the horsepowerfreaks Goliath exhaust for my supra, and in the video on there site of the exhaust ( http://www.horsepowerfreaks.com/pric...xhaust_Systems ) it says that its the 4" Goliath system withe a 3" downpipe and test pipe, how does that work with the Goliath being bigger than the downpipe and the test pipe?

Thanks

Matt

sounds like it works pretty friggin well,

thats kwnates car here i think. ask him.. ;)

With the stock turbo, a 3 inch downpipe and cat back would be fine. I was running a stock turbo but not anymore. I bought it cuz I knew I would be upgrading my turbo and didn't want to replace my catback at that point. This thing is very well built, sounds amazing, and is 4" Stainless steel. Basically this is the only cat back you'll ever need to buy. I have more pictures at home, but its on my computer that needs a powersupply... At the engine side of the cat back it reduces to 3" so you can hook it up. Call up Horsepowerfreaks and talk to Jeff. I love mine and can't wait to hear it with a GT40R on my car :) If you don't think you'll need 4" they offer it in 3.5" too.

Yea I plan to upgrade my turbo eventually, but right now i wanna run just a full cat back with no cats and a test pipe, so as far as i know they only make dp's and test pipes in 3 inch, so I'm still confused as to how they both up with the goliath being 4 inch?

Matt

The piping reduces to a 3" flange. It will bolt to any of these test pipes http://www.horsepowerfreaks.com/pric...ust/Test_Pipes. Call HPF's and talk to Jeff.

4"? lil excessive isnt it? doesnt really help any going from 3 to 4 does it? im just gonna get one of those 3"downpipes with the elbo on it and from there 3" piping bent the same as stock and hangers welded on in stock position, and weld a muffler with a silencer

You're right it won't make much a difference, until you slap on a big turbo, then it'll be worth it. Anything you can do to improve flow on the exhaust will increase hp and reduce heat. I'll be running a 3.5" dp straight into this 4" with my new setup. If i had 3" or even 3.5" I wouldnt make as much power. If youre not going big, the 3.5 goliath is still big and is stainless, you'll never need a new one.

hope this is ok, but i read Xmans post and jeff from hpf said this on sm once and i though it was interesting for sure and it stuck with me....

Quote:For the naysayers who think 4" is just for show, read this:

Originally Posted by X-man
I dynoed tonite with my 3 inch exhaust system back on the car and found out some interesting comparisons. My previous dyno runs had been at 19 psi on my SP67 p trim with a .68 a/r with 4 inch exhaust and had produced a best of 518 rwhp/ 475 rwtq... Tonite with no other changes produced 425 rwhp/ 418 rwtq and dropped the boost to 17 psi.

In short:
3" exhaust with SP67: 425 rwhp/ 418 rwtq (17psi)
4" exhaust with SP67: 518 rwhp/ 475 rwtq (less backpressure raised boost to 19psi with no change to boost controller setting!) Quote:

so i would tend to believe 4" it definately worth it for big turbos..

You can see gains on a stock downpipe and cat when you install a larger than stock cat-back. Any reduction in backpressure is a good thing, plus from a thermodynamic standpoint exhaust that is close coming out of the turbo is moving very quickly. As it travels farther from the turbo it slows down some and as a result likes to take up more space. Having an exhaust that tapers larger is actually a good thing and is the reason you often see "trumpets" on many race car exhausts (especially if they are open header)

Alright thanks for all the info guys, it's all coming together now!!

Matt