Why most popular Evo exhuasts suck - a tube is not a tube - read - case study
 

Lately it seems that the ebay and other cheap brands made in Taiwan and China exhuasts are becomming very popular

I don't blame people who are looking to save a buck on an exhuast

However, it seems that 90% of my customers don't realize that exhuast design has a significant effect on performance. Most of the customers INCORECTLY ASSume that a 3" tube is a 3" tube. As I showed in my infamous BEER CAN test (do a search)

- many exhuasts have a muffler which is less than 3" inside

- many exhuasts have crazy bends that rob power

- many exhuasts have neck downs at the cat area and multiple mis matched flanges which rob power

- many exhausts have resonators which rob power

Quess what - if that el cheapo ebay crap 3" exhuast you bought has a less than 3" inside diameter muffler, a big S bend, a resonator and necks down at the cat - your CAR IS NOT GOING TO MAKE GREAT POWER ON THE DYNO

It seems to me that the chinese made and taiwan made exhuasts are designed and made by companies that copy each other and have probably conducted zero R & D

I am writing to tell my customers - pick your exhuast carefully - that extra 20 whp you are looking for may be missing if you buy a crap exhuast

Today I installed and tuned a new Buschur 3" Exhuast with bullet muffler & test pipe

It was on a 2005 Evo with

Buschur Intake
Buschur Exhaust
Forge RS Bov
Forge MBC
Walbro Fuel Pump

Custom Buschur Flash

First of all - the Buschur exhuast is super light - saving needless weight

Second of all its nearly 100 staight with zero bends to the back

Thirs it has zero neck downs flanges or resonators - its a straight 3" pipe front to back

Here are some amaxzing results I saw on the dyno

First the stock base line - - vs. the car with just a Dyno Flash and a fuel pump vs today's full Buschur Stage I car

Testing conditions - cold air - 93 octane 22 psi boost

http://i59.photobucket.com/albums/g3...exhcomapr3.jpg

Sure - this car is a beast and it makes more power than many Stage III cars we have tuned lately with cams and some brand X exhuasts we see

Sure it is right up there with Evo IX's with stage I and II with brand X exhausts

http://i59.photobucket.com/albums/g3...05brstage1.jpg

After we finsihed the pump gas mapping we kept the same map and just poured in some C -16 and turned down the MBC to the end for a 29 psi spike and thsi is what we got

http://i59.photobucket.com/albums/g3...stage1race.jpg

In summary, having a free flowing, well designed exhuast is key if you want to maximize the power potential of your modification plans

Excellent post. Very impressive numbers as well!

Kenny

Im glad someone addressed this finally. I was sick and tired of seeing that extreme s bend on the rear most section of some Evo exhausts. Thats why I got the JunBL setup that Buschur sells, with the larger cat adapter. Good price, all stainless, straight, and passes the beer can test.

Damn Al you had me all worried about my Helix exhaust a quick run to your thread showed my choice in helix wasn't totally unfounded :P

https://www.evolutionm.net/forums/sh...highlight=beer

i agree 100%. if you want something done to your car, do it right. don't try to take the easy way out, but you sure as hell don't need to spend like 2k for an exhaust haha

looking at 5200 rpm to see which HP lines go with which TQ lines it looks like the middle graph is really weird, im having a tough time understanding those graphs or they are really funny curves.

would be nice if you could have slapped one of the "X" brand exhausts on they are "Cheap" like you said that way we could really see a REAL comparison, maybe you guys should invest in a couple "X" brands and im sure you would make more than your money back asap with customers buying your good exhaust.

just saying yours is better with some good numbers doesnt do it.

good luck with everything!

Glad I'm still running my Buschur exhaust!

hmmmm
very informative but obvious...atleast for me:)

This customer that was the subject of this thread had the weakest stock Evo we ever saw

He was the guy I previously wrote about who had been ripped off by a used car purchase when he bought a MR Evo 2005 that had its MR wheels missing and its interior also swapped for a non MR interior - anyway you dont forget that kind of car

Stock was the lowest curve

I flashed it - installed a MBC and a Pump and that was the center sheet

At the top is the same car with Buschur Stage I

just meant the middle curve, the HP looks more flat than usual. looked confusing, i see it now, just thought it looked funny.

The car in question is an 05, on the first plot the two lower runs are a 05 evo then the highest is a 04. The last two plots are for a 04 what is the deal with that? It looks like two different cars are being compaired.

Disregard that - the dyno assitant erroneously inputed 04 in todays info

The number of the dyno file shows the serial number of the vehcile - its all the same car

Those curves are totally wack. What is with the HP flatline of the middle curves? The start times of all three are off as well. The end slopes and points of the torque curves don't match up either.

This is also not a case study since you don't have a comparison of the other exhaust you are speaking of.

this may be {offtopic} but what do you mean by non-MR interior? you mean he got SSL leather seats? and from what i've seen, the megan is 3" all the way through.

Another funny anicdote anout this car

Another 05 we are working on is one of the only girl owned Evos I have ever tuned, owned by a yound lady who studies mechanics. In any event, her car was eroneously towed by a slimey tow company on 2 wheels and as a result it melted the active center diff and started a small electrical fire in the engine compartment

In any event, the young lady took the opportunity to do some upgrades on here MR which happened to already have a el cheapo e bay china junk exhuast

She added a BR Intake - HKS 272 Cams and a BR Evo Green 20G Turbo

All with that same el crapo e basy 3" exhuast with major s bend and the stock fmic pipes and fmic

Her car bearly made 335 whp with great effort and a lot of time on the dyno.

Its amazing to me that two 05 evos are making similar power and one has cams and a larger turbo - (and e bay exhuast)

A testing session confirmed that the Stage I car with Br Exhuast beat the 20 G camed Evo with e Bay exhuast by a slight margin