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Hi again all,
I have been give several meters of decent steel tube which is roughly the same size as the exhaust section on my fourtrak (yet to measure exactly).
Having already patched the odd hole, I will soon be needing a new centre section and have toyed with the idea of making a straight through piece.
Has anyone done similar? are there pro's and cons to removing the centre box...noise will obviously go up, but does it sound ok? or like it's about to fall apart? would there be much gain / loss of power in doing this?
Cheers for any advice,
Martin
There are both. The pros are
There are both.
The pros are that by removing a restriction you will have a more responsive engine.
The cons are that the engine needs this restriction for several reasons, and exhausts are designed for this.
Scavenging effect, this leaves a little exhaust gas in the combustion chamber, and aids engine torque.
Without this restriction the turbo may spin up quicker and leave the engine short of fuel for a short period of acceleration.
The cooling affect, the centre box has a larger area for cooling, and slowing down the exhaust gases.
Why not make a new centre box, if you can make the exhaust then a centre box is easy. Cut it open and see the layout if the perf tubesand replicate them, just make the casing out of much thicker material.
there is a bit ontop of the
there is a bit ontop of the fuel pump that sorts the on boost fueling,it makes no difference when the turbo comes in or how fast as it use a pipe that carreys boost to push a diaphram down to give on boost fuel.
the more restricted the exhaust is the hotter it will get so a bigger free flowing one is best.
anything after the turbo is a restriction,the turbo its self and the manifold will give more than enough back pressure for the engines needs.
i have built my own exhaust,well i have built 2 now.
first one was 70mm from the turbo down pipe back with this box on
http://www.merlinmotorsport.co.uk/p1556/JETEX-TURBONETT-ROUND-250MM-LONG-3-INCH/product_info.html
it sounding ok and made it feel better.
then i swaped that box for a 3" cherry bomb and that sounded better.
then i redone my exhaust and used 3" pipe with flowed bends(not cut and weled bends like the first one) and the cherry bomb but i done away with the turbo exhaust elbow and made my own but with a scremmer pipe,now this new down pipe/exhaust made the turbo come in soo much faster and harder and imo is well worth it but i would plumb the scremmer pipe back into the exhaust lower doen as that made it realy loud.
now i here you say "whats a screammer pipe"
well on the turbo you have a waste gate that opens up and lets the exhaust gasses by pass the exhaust turbine to keep the boost to the set psi,now when this re enters back into the exhaust gass flow from the turbine it messes with the flow and gives back pressure so a screammer pipe vents this to the atmosphere but sounds like a jet and is illegal on the road so would be best for that to re enter further down the exhaust into a bend as it should then follow the flow of gasses better then.
anyway i say if you have the tube and can do it give it a try and if you dont like it you can then go back to a standard one
When very short of cash I
When very short of cash I used an old V8 Range Rover exhast to cut up and weld back together to fit my F50 (non-terbo obviously) Could only use the rear most reverb box, as the silencer proper was beyond use. I was amazed at just how sivilized the noise level was, and it did actually go better than with the original. Weird.
Any veiws expresed in this thread by me are purely from my own experience, and (sometimes) falible memory. Hope my comments help, but please don't take them as gospel.
done n dusted, look at my
done n dusted, look at my youtube.
Full of ideas but no time to do them!!
www.bloodredoffroad.com
www.milneroffroad.com
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