[Shotimes] Rod shifter/exhaust question

[cmichaelo@optonline.net]

Yes, I can imagine that you would loose some low end torque, but not as much as you would with a catback that uses 2 1/2" piping all the way through.

Michael
94MTX,green,BOS+,Koni/Intrax,Baer,Corbeau
SHO items for sale: http://hometown.aol.com/cmichaelo/for_sale.html

----- Original Message -----
From: ROBERT SCHIRMER <1surferbum@msn.com>
Date: Thursday, October 28, 2004 6:56 pm
Subject: Re: [Shotimes] Rod shifter/exhaust question

> OK, now you got me thinking. I was under the impression that the Y 
> pipe was
> NOT a restriction for the ATX cars, cause that Y pipe was larger 
> than the MTX.
> Now, if you go to a high flow cat system on a ATX, won't you lose 
> low end
> torque if you use a 2 1/2 inch  (OK, partial 2 1/2 inch) cat back 
> system???  ----- Original Message -----
>  From: cmichaelo@optonline.net<cmichaelo@optonline.net>
>  To: Ed Cizmar<ecizmar@earthlink.net>
>  Cc: ROBERT SCHIRMER<1surferbum@msn.com> ; Ian
> Fisher<dataflash@yahoo.com> ;
> shotimes@autox.team.net<shotimes@autox.team.net>
>  Sent: Thursday, October 28, 2004 1:26 PM
>  Subject: Re: [Shotimes] Rod shifter/exhaust question
> 
> 
>  Ed,
> 
>  Here's a relatively cheap way to fabricate an "optimal" 2 1/2" 
> catbacksystem for the SHO.
> 
>  First, I'd buy the Dynomax system, which is basically a 2 1/4" 
> system,though with a 2 1/2" piping used for the snake section.  I 
> would then drop the
> 2 1/4" resonator section and have that section custom fabricated 
> in 2 1/2"
> piping with your own personal resonator (many seem to prefer 
> Magnaflow.)
>  The Dynomax snake section is already fabricated in 2 1/2" 
> piping, so you're
> ok with that piece. The only caveat is that the branch section of 
> the Dynomax
> catback is fabricated in 2 1/4" piping.
> 
>  However, IMO this won't hurt mid/high-end performance since by 
> the time the
> exhaust gases reach the branch section the velocity and volume of 
> the gases
> have sufficiently decreased and thus no longer require 2 1/2" to 
> flow freely.
> In fact, you may even benefit from keeping the branch section at 2 
> 1/4" since
> it will increase back pressure at lower RPMs.
> 
>  So I kind of view this "home made" exhaust as the optimal 
> exhaust for the
> SHO.
> 
>  Going 2 1/2" all the way, will hurt low-end performance. 
> Everyone seems to
> have noticed this. But by compromising right in the middle, and 
> graduallydecrease the cross section as you move further backwards, 
> I'm hoping this
> solve this deficiency somewhat.
> 
>  Be adviced, however, that if you have a 2 1/4" Y-pipe outlet, 
> you won't
> benefit anything from the 2 1/2" catback. You'd have to cut out 
> the 2 1/4"
> Y-pipe outlet and have a 2 1/2" outlet welded in. (If you're 
> interested, I can
> tell you more about how exactly to do this, cause I just did it.)
> 
> 
>  Michael
>  94MTX,green,BOS+,Koni/Intrax,Baer,Corbeau
>  SHO items for sale:
> http://hometown.aol.com/cmichaelo/for_sale.html<http://hometown.aol.com/cmich
> aelo/for_sale.html>
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