Contour Enthusiasts Group Archives Forums Modifications Forced Induction F/I exhaust diameter??

Okay everyone, here's the situation I'm in: SF turbo kit is on order, and I currently have the Bassani/Msds combo. So my question to everyone is: Will my Bassani flow an adequate amount of exhaust? Josh at Yodude is very interested in my headers, and has placed an offer on the table: 3" stainless Magnaflow setup plus "some" money. So what is everyone's take? Go with the Yodude or keep the Bassani and get some Stage 2 axles? I am a bit weary of the single muffler setup, but I don't want to be choking the turbo with to small of an exhaust, ya know?

I have a Zetec so I'm assuming the Bassani is a catback dual exhaust system? If the pipe diameter of the Bassani is at least 2.25" I would not worry about upgrading. If it's less than that, get the 3"!

wavrdr-

I have already discussed this with Keyser. The adequate diameter for the turbo is 2.5" if your Bassani is that big you will be fine. However I personally have a YoDude and would recommend it, especially if Josh put that deal up. 3" is best for the turbo . It's really up to you at this point.

Alan-

Exhaust gets more restrictive as it flows out. The bigger it gets on the way out the better. 3" cat back would be best for the power you want. You could squeak by on 2.5 but the Bassani is only 2.25. My set up is a 3" cat back to a 2 x 2.5 and then out. So doing some kind of crazy math it comes out to 6" of flow coming out the back going into 2 x 2.5.

When I said at least 2.25"...I mean for dual exhaust 2 x 2.25. I take it that it pipes down to a single pipe somewhere...you would definitely want it to be 3" there.

2.5" single pipe = 4.91 square inches
3" single pipe = 7.07 square inches

BIG difference!

But you would prolly want to maintain the look of the SVT with dual exhaust, and what Keyser did with having 2 x 2.25 is ideal.

2.5" dual pipe = 7.95 square inches

A little more/similar flow to the 3" single, and you keep the look.

Originally posted by Ausgedient:

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2.5" single pipe = 4.91 square inches
3" single pipe = 7.07 square inches

2.5" dual pipe = 7.95 square inches

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How can 2 2.5" pipes which have 4.91 sq/in each seperately = 7.95 sq/in when combined. They'd equal 9.82 sq/in (2 x 4.91) I think you may have meant dual 2.25"???

2.25" = 3.98 sq/in
2.5" = 4.91 sq/in
Dual 2" = 6.28 sq/in
3" = 7.07 sq/in
Dual 2.25" = 7.96 sq/in

Exhaust Advice

If you want to retain dual outlets (to nicely fill the exhaust cutouts & not look like CRAP!) you could do 3" single to 2.25" dual.

This way you only have to fabricate the 3" part yourself (NO F'n Crush bends either!) and tie it into the Bassani 2.25" dual section.

Also if you are up for max performance. Ditch the performance robbing baffled style Bassani mufflers for a set of straight through's.

However after all of that you could just sell the entire Bassani setup and build one from scratch. This is definitely what I would do.

You could probably build one yourself for what you could sell the Bassani for! Fabbing it up is really easy if you use an F-body style rear muffler (been there done that ) Doing it this way equals 3" single pipe to 2.5" duals. Definitely plenty of flow!

Don't you have to multiply by 3.14 to get volume anyway?

Yes I meant 2.25" but the eye to hand coordination was apparently having some difficulty.

I'm going 3" Mandrel Bent (courtesy JC Whitney) from the cat back, to a 3" Magnaflow "Camaro-style" muffler, exiting with dual 2.5" tips. Flow galore!

Originally posted by Stazi the Aussie:

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I'm going 3" Mandrel Bent (courtesy JC Whitney) from the cat back, to a 3" Magnaflow "Camaro-style" muffler, exiting with dual 2.5" tips. Flow galore!

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This is a similiar setup to what Josh if offering: 3" "headpipe" to a single Magnaflow, or Flowmaster, and dual 3" tail pipes to retain a somewhat factory look. I was planning on selling the Bassani if I take part in the trade, just wanted everyone's opinion. Thanks!