[Sangria7]

Hey guys

Anyone have experience on applying the exhaust wraps on their pipes. I read somewhere that wrapping pipes MAY require a rejet as it makes the outflow faster because the heat velocity is increased due to the wrap keeping heat in. Sounds logical but if I dont intend to wrap all my pipes just the front half coming from the engine itself.

Let me know if anyone has experience on this…Munch?

[Munch]

I am unsure as far as bikes go but I will look into it. However basic engine operation…
Free flowing or even accelerated exhaust only effects the motor if it’s backed up or requires back pressure for efficient engine operation.
If its restricted it’s like inhaling from a pipe and trying to exhale from a McD’s straw.
Accelerating the flow only lets you get out the exhaust faster allowing the potential for more to get out. If you remap the fuel and air to get more power you will need a free flowing exhaust. If not.. well you wasted a lil bit of money for cool aesthetics of wrapped pipes and maybe keeping the heat off your legs.
edit: hope that made some sense…I typed it during class and trying not to get caught….shhhhhh

[Munch]

Ok…. it depends on type of motor…. FI or carb’ed. Carbs you can fudge more easily and definitely need to get a more open flow out. IF your adjusting the volume of the fuel going into the carb….but that would be re jetting now wouldn’t it. Unless your just playing with the fuel mixture screws.
All vehicles have been set up from factory to run optimally efficient for the market they are meant for. A marginal way to “hop” it up could be to open the exhaust up, again its a marginal gain. It can breathe out better but your not really get more in. Assuming the motor does not require back pressure to help the motor efficiently keep the “crank” turning, if it does you could be potentially doing more harm then good. FI really is more marginalized (w/o a chip or programmer) due to the PCM and sensors that monitor all things. It will see the variances in the fuel mixture and exhaust mixtures, air mass, content etc and adjust accordingly… that’s why so called “cold air intake” kits are really wasted spending unless your gonna go full bore into the project. Exhaust adjustments usually go straight pipe, bypassing muffler “restriction” and/or catalytic converters (illegal) that give the exhaust some but very little restriction. Usually most cost effective way to get the same “boost”. Either way the exhaust valves will still open at the same times and get the same volume out the difference is just free flow. Are you doing any better for yourself if you inhale like an asthmatic but can get it out like a jet blower?

To answer your question simply…. a lick ….yes….more then a tad….no.
Any real performance gains need to start at the beginning of the process and be adjusted all the way to the end of the process….not the other way around. Want more power? Re jet, re program, bore it out, get a stronger spark, a fuel pump that gives more volume, change timing, open up the exhaust, lower the total weight of the vehicle….the list goes on and on. Meanwhile you are also limiting the life of said motor.
If the very minimal 10hp is enough for you… you might ….underline…MIGHT..get that from a free flowing exhaust, it however will not be noticeably felt.
Ummm… I think I am done for now…. for what my wore out brain can push out… sorry IT classes, and test (which I passed by the way) and a very long day have me kinda jumbled up in my head. Hope that answered a lil of your question…. oh yea… I also didn’t go into gear reductions and so on and so forth to transform any new hp from the motor into usable hp to the ground.

[Sangria7]

Munch – that was a good response! But unfortunately I have no idea what you just said LMAO. It was like reading a thermal dynamics physics book HAHA..Just kidding man.

I was only trying to wrap the actual pipes for aesthetic reasons (ie for the black out look) and I dont think it will give any performance increase (I may be wrong). Also I was trying to reduce radiant heat from the pipes as its only 80deg here in Houston and I can feel my pipes already when in dead stop traffic.

The wraps from what I understand keep heat in the pipes instead of radianting them normally. The insulated heat increase air flow in the pipes thus the outflow has increased velocity. Hopefully it doesnt increase velocity that much that it would require rejet.

[Munch]

should do just fine for those purposes. Just know that the exhaust will not induce a NEED to re jet. Flip side a re jet will provoke the need for a more free-er flowing exhaust.

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