The manufacturers always exaggerate.

 

dyno proven. Check ads for dynocharts. APEXi exhausts have always been dyno proven, both my manufacturers and independent shops.

I see why you're not an import auto expert. You don't believe in anything

 

Liars can figure and figures can lie.Yes,turbo cars respond better than NA cars to bolt ons.But don't believe everything manufactures say.Split fire plugs add how many HP?I've never heard of anyone that races that uses those plugs.

 

Uh, the reason why it gives so much horsepower is because the stock OEM exhaust is VERY restrictive. More restrictive than normal, to keep the horsepower down.

Thus when you rip that piece of junk out, and put in a real exhaust, you see larger than normal gains. In other words, the stock exhaust is MORE restrictive than what you would expect, thus a 3" more straight flowing exhaust gives more horsepower than normal.

Get it?

Mordeth

 

This is true. I would have a hard time beleiving it myself if I had not experienced what opening up the exhaust can do. I had a stage IV Stillen 300ZX twin turbo. One day I decided to punch out two of the four cats.

HOLLY CRAP my Z came alive after that. BTW If you have never seen a what a cat looks like before, just imagine a honey comb mesh with the holes too small to stick a pin through. It is a freakin cork.

I think doing that free mod gave me more noticeable results than any other single mod. I already had a Trust exhaust, Jim Wolf POP charger and ECU, and a profec.

I wonder if that exhaust claim of 37HP is peak or at just one point in the power band? Also I would like to know if that was with the factory cat.

 

Are you guys talking about the APEXi Hayabusa? If so, I posted some pics in this thread: http://www.lancerforums.com/forums/t3822.html

 

Don't forget the downpipe!

 

And I thought more people would be interested in the price he was told not the thing about the exhaust. Oh well

 

Not Hayabusa. Hayabusa only added 30rwhp for Evo 7 (yes still good). This new exhaust "R-95" has a 4" pipe all the way after the cat. 38+rwhp proven.

BTW APEXi exhausts are usually underrated, as they provide more HP than APEXi claims (from Option Magazine dyno tests.)

 

Personally, I think very unlikely that gains of that magnitude are realistic, regardless what the manufacturer says.

I have both an Evo 5 and an Evo 7, know several other guys with tuned Evos, and nobody has ever seen gains that big, PURELY from exhaust. I've got an Apex'i full catback and downpipe system on the car, by the way.

The engine guru who built Manuel Go's 523HP (@ the wheels) Evo 5 is also very skeptical that those sorts of gains can be had from JUST exhaust.

But if anybody here actually gets those gains, independently verified on a dyno, I'll be fighting to get to the front of the line to buy one!

Cheers!

 

There you have it.

 

Yep I agree. There is no way a cat back by itself will give you a steady 30+ hp gain. I have seen alot of cars get dyno tested and if there is ever a gain that big from a cat back it is always peak to peak #'s. Peak #'s mean very little in my opinion. I do believe you could get significant gains by freeing up the whole exhaust system...especially when boost is increased.

 

well, we'll see when Evo7 comes out here and someone gets this exhaust.

 

A peak gain of 30hp is believable, at least on Japanese gas. I'd gotten a huge gain of 40hp with a cat-back Fujitsubo Evo R on my past Legacy - but that was only at 3000rpm, going from 70hp to 110hp at that particular peak. Peak hp only went up 15hp or so, OTOH, and the overall avg. would probably be closer to that, just 15hp or so. That doesn't make good advertising, so manufacturers usually pick out the highest peak, whereever it is, and use that for the figures.

I saw one Japanese tuner strike back at that - they were making SR20DET cams for high-hp purposes, but instead of making one that gave you a huge hp peak, they made one that gave a huger, flatter torque at low- to mid-end, and then went to pains to explain how that would be faster *overall* than a laggy, no-low-or-mid-end engine that made 50 more hp than their kit at 6000rpm.

IMO, look at the overall dyno curve for a muffler, and buy based on what it does for hp and torque underneath the peaks. If you give up -20hp under 3500rpm for +30hp above 4500rpm, it may give you bragging rights, but the only place the car will be faster is on the track, and even then that's debateable depending on how you use the engine.

Paul Hansen

 

Hi Paul,

Is the Fujitsubo cat back well made? I'm looking at the RM-01A cat back for my upcoming EVO 7. I plan on using the Mines super outlet turbo elbow -> a 3" down pipe (Fujitsubo again probably) -> Hi flow 3” cat -> the RM-01A cat back. I don’t expect 30 hp from the entire system.


Erik