Re: cracked 2-piece manifold for MC...

[OorQue@aol.com]

>  If I'm not mistaken Jeff, you have a two-piece.  Is it still a non-mounted
>  item?  Maybe if you've got the one-piece off your UrQ or 200tq at the same
>  time we could finally get some real numbers.  I for one (and others) would
>  love to finally see some definitive data.

I have in my garage four stock one-piece EMs, a one-piece EM that has been 
Extrude Hone'd (this was formerly Ben Howell's Ur-Q manifold) and a ported 
two-piece EM.  I have also done a limited amount of flowbench testing on 
these EMs but have some doubts about its relevance.  For a start, it's pretty 
hard to arrange to flow air through all five ports at the same time; also, 
because these are designed according to pulse-converter theory, testing them 
by themselves (instead of with a turbo on one end and a cylinder head on the 
other) may not allow them to function properly.  This is especially true when 
trying to determine the performance benefits of such things as ceramic-coated 
ports, etc.  

As such, I think the only way to get a real handle on this is through dyno 
testing: either they generate more torque or they don't.  Unfortunately, dyno 
testing my 200q will be difficult due to the Torsen center diff, but it 
should be easy on my Ur-Q since its center diff can be locked and the rear 
driveshaft removed.  There are a few Dynojets in town and I'm planning on 
doing exactly this once I've got the 2.5L motor installed.   

>  Will the two-piece turn the car into a rocket? No.  It is like many things
>  we tweak on our cars. . .progress.  How much more power does a 2.5" or 3"
>  exhaust with freeflow muff. or no cat give?  Who knows.

Again, I think dyno testing is the only way to answer these questions.

JG