Hi, i have a 99 z28 and i have slp loudmouth exhaust, my friend was telling me that its not a good exhaust because there is no back pressure because of no muffler, so its going to wear on my valves. So i wanted to know which one was better Applied or Random technology? I am looking for both sound and horsepower gain. Thanks alot!!!

 

no offense but i think your friend is full of s**t.....

in all seriousness, i've never heard of lack of backpressure wearing valves.......(somebody correct me if i wrong)also if you have stock cats and stock exhaust manifolds, the loudmouth is not going to lose a whole lot of backpressure anyway...I run the loudmouth with NO cats and LONGTUBES and i still have good torque (349 Rear wheel) and no apparant problem with "worn valves"???? also in my opinion the loudmouth is one of the best sounding exhausts on an otherwise stock LS1....neither one of those other catbacks is going to make as much power and honestly the random tech one doesnt sound too good in my opinion, haven't heard the other....i say keep the loudmouth....

 

Your friend is a tool. And you wont see any difference is power between the SLP LM, or the Random Tech catback. I prefer the Random Tech, but thats just my own personal taste.

 

I would not go with the Appied or Random Tech, in fact I have never heard anyone even mention those names when talking about exhaust.

 

Thats because not everybody and their mom has it. They are in fact very good exhaust systems. I can see that you are the kind of peson that only buys things that others have, which sucks, because there are tons of other smaller companys that offer better proucts than you will find in most magazines and catalogs. Also, the Random Tech catback is the least restrictive catback on the market today, even less restrictive than the SLP LM.

 

Sorry he said the Valve seals, MY buddy said that since im taking off my cats, and putting headers and a Y pipe there wont be much back pressure, Anyone know anything that could help me ??

 

No one i know has slp i was the first around my town to get it.

 

i would really like to keep the slp because i love the sound, has anyone dynoed the slp exhaust and if so how much did you get?

 

just stick with the loudmouth. you still have sufficient backpressure even with headers.

probably hundreds of people are running similar setups...and without problems.

although it will be LOUD

 

I've seen dirt track and drag cars run headers only on an engine for a full season of racing and never have any valve or seal problems.

Here is a little physics for you. greater pressure = greater temperature and less pressure = less temperature

So, how does having more back pressure decrease heat since that would be what would destroy the seals?

 

Backpressure is a bunch of bull and you do not want an exhaust that will cause any backpressure.Whoever talkes about not having enough backpressure on a v8 is full ot it.Backpressure is only good for small engines preferably 2 stroke engines to kepp the incoming air charge from coming through the cylinder and out the exhaust before the piston comes up and closes the exhaust port.Now thats on a 2 stroke motor that why if you dont know how they work you may not have gotten that.But on a v8 backpressure hurts horsepower its air velocity your after.If you have small headers on your car and put larger headers on that may possibly be to big for your engine you will have some idiot say you will lose backpressure with that larger exhaust when in reality you will lose exhaust velocity and the exhaust will slow down actually causing backpressure and hurting your horsepower.If you put real long headers on your car you will get great velocity at lower rpms and short headers will give you great velocity at higher rpms.It works with the exact same way an intake manifold does.Do 6000 horsepower drag engines have open headers for #@$% and giggles?

 

correct....as i stated, i have LM, longtubes and ORYP and i dont have any problems (other than annoyed neighbors )....you need SOME backpressure on lower hp motors to keep your low end torque from moving up in the power band but believe me having a Loudmouth is NOT goign to hurt valves in any way, even with headers (once again though this is a LOUD setup)

 

ok well thanks for all your help, so eveyone is agreed that it doenst hurt the seals. So i should keep it. Has anyone dynoed the slp exhaust, and should i get slp headers and y pipe?

 

i want my car as loud as possible

 

SLP headers are good but a lot of people have ground clearance issues with them....i vote Kooks stainless if you have money to burn or Pacesetter coated if you dont want to spend a whole bunch on headers....as far as i can tell pacesetters seem to perform just about as well as any other brand at a fraction of the price...(mine were 330 bucks plus y-pipe for 120). there are sometimes some minor fitment issues but nothing serious....