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4" vs 5" exhaust

Power, none. Egt's, a slight drop. There really isn't much of a benifit aside from the cool factor. I had 5" on 2 trucks and it is badass. If I were to do exhaust on this truck, I wouldn't waste my $$$ on a plain ol 4" kit.............JMO.
 
you will lose low end with a 5"...4" is the route to go unless you are pushing over 500hp..

Cooling wise, the 5" will keep your EGT's down lower than the 4" but once again you get back to the 500hp thing....
 
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I'm so glad that I ended up going with the 5" system. My "seat of my pants" gauges, I don't feel that I lost a lot, if any low end power. Might have, but I don't feel it. And now with the predator on 85hp, I have very quick thottle response and now I don't feel any lost of TQ. As for the cool factor, OH YEAH! Love the look of the 5" exhaust over the 4".
 
I run a 4" with a 6" tip and it looks great...when I finally break down and buy a d-max, i'll run the 5" only because I plan on pushing 800hp streetable
 
DunesRunner08 said:
Cooling wise, the 5" will keep your EGT's down lower than the 4" but once again you get back to the 500hp thing....
Click to expand...


Not on the LB7 I love my big 5"..... In fact the spool up is so much better than the straight pipe I had.

Besides Its flipping cool. I will get the 6" tip someday....
 
You don't lose bottom end, that is a myth. I like my 5" but there is no real advantage. I don't want to hear the 'backpressure' argument to the 5". The turbo itself is plenty of backpressure.
 
Cheyenne19 said:
You don't lose bottom end, that is a myth. I like my 5" but there is no real advantage. I don't want to hear the 'backpressure' argument to the 5". The turbo itself is plenty of backpressure.
Click to expand...

X2. You could run an open turbo and you wouldn't lose low end power.
 
Cheyenne19 said:
You don't lose bottom end, that is a myth. I like my 5" but there is no real advantage. I don't want to hear the 'backpressure' argument to the 5". The turbo itself is plenty of backpressure.
Click to expand...

got-h2o said:
X2. You could run an open turbo and you wouldn't lose low end power.
Click to expand...

You lose low end pressure? Nobody told me... I will check that out next time I am smoking out the guy next to me.... :)
 
I can see a slight loss in low end power due to the fact that the turbo uses the exhaust flow to spool, so with less backpressure in theory it would take longer to spool and hold it for a shorter time between shifts and let offs. Then again, I am a seat of the pants guy, and there is always a "sweet spot" for everything which may very well be a 5" exhaust being used....
 
True, but the turbo outlet is way smaller than any pipe you'll put up next to it, especially front pipe back.
 
i'm running a 5 inch on my truck. i like it, the only thing is don't get a cheap kit when you get one or it will be a pain in the ass to install. buy a good kit. i had to do some mods to mine to get it to fit right and i'm still not happy. i'll get it positioned right eventually.

i've got a 6 inch tip on mine. i think it looks badass.
 
jcool said:
I can see a slight loss in low end power due to the fact that the turbo uses the exhaust flow to spool, so with less backpressure in theory it would take longer to spool and hold it for a shorter time between shifts and let offs. Then again, I am a seat of the pants guy, and there is always a "sweet spot" for everything which may very well be a 5" exhaust being used....
Click to expand...

got-h2o said:
True, but the turbo outlet is way smaller than any pipe you'll put up next to it, especially front pipe back.
Click to expand...
Exactly, so the air velocity at the turbo should in no way be affected by the 5" system behind it.
 
I have a 4 inch stright pipe on my truck now, I think it sounds great, but I stumbled across a deal that I couldn't pass up and traded someone elses factory exuast for a 5 inch for myself. It is sitting on the side of my house, not sure if I should put it on or not.
 
what about sound differances between the 5" vs. 4" as in 5" & 4" system with a muffler and 5" & 4" without muffler??
 
Philbilly2 said:
I have a 4 inch stright pipe on my truck now, I think it sounds great, but I stumbled across a deal that I couldn't pass up and traded someone elses factory exuast for a 5 inch for myself. It is sitting on the side of my house, not sure if I should put it on or not.
Click to expand...

i think you should pass on it and send it to me. you dont need that kinda noise on your truck :D:p
 
bitchin..... i'll be expecting sometime between thurs and....never..... right??? :D

seriously, im goin for a pipe.... one of these days. factory straight is ok..... needs improvement though... :p
 
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