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exhaust question

blind655

Well-Known Member
What is better to run…Side exhaust or a turndown off the muffler?

Thanks
Mike
 

ntsqd

Well-Known Member
I'd think a turn out. Turn downs are illegal at the El Mirage dry lake races because they raise too much dust. I'd think the same applies here. A turn down could raise a lot more dust than a turn out so even if it's legal to run a turn down, a turn out will be a lot more comfortable to be around.

"Teach you all I know and you're still stupid"
-- Howdy Lee
 

vwguy

Well-Known Member
better as in which is better for performance or better for the smog guy not to complain about

turndown after the muffler is just less to break off while romping or jumping the truck but the smog guy might complain that he has to go under the truck to get to the exit and get his ben davis work shirt dirty

exhaust is to complex to tell which is better for performance. exhaust pipe length, diameter, and other variables

exhaust backpressure is another thing that is easier to know the consequences of changes. less length or larger diameter pipe will make less backpressure and will get you better top end but less bottom end so more mph but less torque. and vice versa a small pipe or more length will give good bottom end but less top end. that is why other motorsports have tunable mufflers.

just play with it to see what is good and get a good balance it is known as exhaust tuning

how ironic is it that most people slow down for speed bumps yet almost all of us here im sure pin it

as for stirring up dust my brother runs turndown and he has no asphalt or concrete on his property so its in the dirt all the time and i see no dust being bothered as long as he doesnt have a bagged toyota on the ground<P ID="edit"><FONT SIZE=-1>Edited by vwguy on 10/14/01 10:01 PM (server time).</FONT></P>
 

JCA

Well-Known Member
What would be the diffrence of heat. A turn down would keep more heat under the truck, wouldn't it? Probably not much but if you are racing in high heat already every little bit counts. I am putting headers on my race truck and some people are suggesting that it is impairative that I run the headers and exhaust out the fender wells and down the outside of the frame, because of the heat generated.

J.C. Andrews
Andrews Racing
<A target="_blank" HREF=http://www.andrewsracing.com>www.andrewsracing.com</A>
 

scott

Well-Known Member
It would have more heat underneath the vehicle, but how much more??? Is it enough to heat up the rear-end??? I know it does create more dust, but thats pretty cool !!!!!!
 

Kritter

Krittro Campbell
JCA:

Thats pretty tuff to do on a 7s because the fire wall is in the way or maybe I misunderstood you. We(Davis Motorsports) just had some built and they are bitchin and they go inside the frame rails.

When in doubt, GAS IT!
 

JCA

Well-Known Member
My understanding of firewall is the area behind the motor intended to provide a fire barrier between motor and cab. then you have floor and wheel wells and according to the rules you can modify these for running exhaust. This would be a safety item checked during tech prior to a race. My truck when it was being built had the floor/wheelwells modified for headers and has been through tech for both BITD and SCORE without a problem. Not saying putting the headers in to run on the outside of the frame rails isn't a challange even still. That is why I asked the question about the heat. At this point I think I would prefer to run the exhaust inside of the frame with a out turn tail pipe just below the frame. How much of a diffrence of temp for the transmission and cab by running in or out side the frame can be expected?








SCR43: Floorboards

Alterations to floorboard, for the routing of exhaust to rear of vehicle, are permitted.



part that is directly behind the motor

J.C. Andrews
Andrews Racing
<A target="_blank" HREF=http://www.andrewsracing.com>www.andrewsracing.com</A>
 

vwguy

Well-Known Member
just dont have your exhaust strait back into your axle 6 inches away and you should be fine

how ironic is it that most people slow down for speed bumps yet almost all of us here im sure pin it
 

blind655

Well-Known Member
thanks for the help..


Later
Mike
 
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