Hi this ryan~

I looking forward to buy EVO X in 3 weeks GG or WW. I was looking thru the site

for exhaust and other goodies. HKS exhaust looks good. previously had 07 350Z

w/ HKS hi power exhaust. when I had 350Z w/ HKS hi-power I lost HP. I like HKS

sounds. also HKS hi-power for S2000 loses power i heard and saw at S2ki forum.

If someone has the HKS on their EVO X. please tell me and can you give me

some video clip?

I am considering Greddy Trust Power Extreme Ti and HKS Legamax. ARC looks

good but just too much for exhaust.

 

The stock exhaust is so bad anything will make more power.

 

actually sold 7 units of these never 1 had an issue.

 

I am currently using that exhaust and I like it.

 

just curious? i know the hks legamax piping is a little bigger than stock, but i know its not 3"! I was wondering anyone here running a 3" test pipe or hi flow cat and 3" downpipe with the hks have problems?

 

I think the loss in power was due to those being n/a cars. And the stock pipes are tuned to a certan length and backpressure.

On a turbo car it is a totally different story. Bigger = best-er

 

i have the legamax and the center pipe along with UR test pipe and xtremeboost downpipe with no problems at all!!

 

thanks..still seems funny to me going from big to small!!

 

HKS exh is not a 3 inch, its about 2.90-295 if im not mistaken..It tapers down to 2.5 at the cat

 

You can make as much WHP with the test pipe and the stock exhaust then many after market one at the stage 1 level.. The X exhaust is some how works good.
Now , i'm sure when you go over the drop in , or intake , will start restrict , but for just a drop in and tune. it makes a crazy whp.
Like if you have a drop in and the tune +test pipe. you will make as much as whp with the drop in tune and cat back/ almost any/ + test pipe.

just check it out.

 

Robevo, other mods aside, the stock exhaust piping is really small and the actual muffler can is horribly designed for flow.

 

yea that is true!!! just what i chose to go with!! i may be a lil older than some on here and i kinda like it on the quiet side and that set up works just fine for me!! different strokes for different folks its just whatever you prefer!!

 

yeah looks like , but those bone stock evos making with only tune a great whp and wtq.
Now if you only do a dropp in and the test pipe , + tune.
And you change the cat back only how much whp you will actually gain? 5-10?
So for that modification level the cat back is mostly for sound.
Check out the Dyno runs. You will see what i'm saying.

I have no doubt over that modification level you must change it, but what i'm saying is untill you are not ready to step to stage 2 , basically you dont really gain anything with the catback.

 

I have one thing to add on this matter, JASMA (Japan Auto Sports Muffler Assosiaction) approved mufflers are pretty restrictive. They're just a hair bit better than stock in most cases and to tell you the truth, the stock isn't as bad as most of you think. I have seen some JASMA mufflers that are even more restrictive than stock. The problem with the JASMA mufflers are that have to clear many strict tests including a db test. This is what makes it so restrictive, especially with a single tip bullet exhaust. In order to clear the test they have to put restrictors inside the resonators and mufflers making the inner diameter about 2 inches to clear the tests (Kakimoto & Trust). Even with 3 inch main pipes the inner diameters of the resonators & mufflers kill the flow sometimes making it worse than stock. The stock EvoX muffler has piping with the diameter of 2.5 inches without any restrictors making it flow better than some JASMA mufflers.

The HKS is also JASMA approved but I believe they use 2.5 inch piping at where the cat connects and 2.75 inch piping for the rest. I have heard that the inner diameter of the muffler is also around 2.75 inches so it is better than stock but restrictive compared to other 3 inch exhaust systems without restrictors. I know most US manufactured exhausts have no restrictors but the price you'll pay is the loudness.

Alot of people here in Japan say that if you want to go over 350whp on an Evo, don't get a JASMA muffler because it'll become your bottle neck.

 

Why pay the extra price for a HKS exhaust? Get an exhaust from one of the vendors here and have a better flowing exhaust for a cheaper price.