The Greddy Ti and ours have been tested against each other already. They made .7 of a whp more than we did and we made 1.3 ft lbs of torque more than they did. I'd call it a tie. So now you have to decide if the huge price difference is worth the weight savings of I think 7 pounds. (My memory might be wrong on that weight but I think it's right)

Also, remember this test was on a fairly weak car. Add 100 whp to that car and then the difference in HP will go up, gaurantee it.

 

So they would put out a bit more horse on a bigger hp car and you would put up more torque you're saying?

 

When you have mildy modifed Stage I stock turbo cars - changing an exhuast may not have as much as a dramatic effect as on more modied cars with say Stage III or IV mods with cams or a larger turbo where a restrictive exhuast will cost you more and more power

A turbo system is like a chain - its only as strong as its weakest link

The more power you make - the more a weak link will hold you back

The gains achived in this test IMHO are impressive considering the mildly modified nature of the car - e.g. - stock air box

 

It would probably depend on what car you tested it on.

 

I love my HKS carbon/ti catback and my full ti JIC catback. Both really nice and the highest quality.

 

why not just swap the exhaust and re dyno, then there is no "oh you tuned it" crap. you also get to see exactly what the other effects of the swap are be it running leaning, more knock, less timing. the average person is not going to have their car tuned every time they ad a mod or change one thing. IMO it makes for more accurate testing as to what the "real world" gains would be. also alot of people on this site do not run a 35r or anything but a stock turbo so why go through the trouble of using a highly modified car when no one cares what it would make. they want to know what it would make on a car similar to thiers. although i understand you test on what you can get. i just think it would be better to take a car with Buschur exhaust and replace it with the other guys then just let er rip. you would get a more complete look at what the exhaust does for the car.

nate

 

I recall you slamming the HKS exhaust a few times. As an example......
Weren't you the same guy that said this about the HKS exhaust.

 

 

It does have a small exhuast orfice - but apparently it is well designed never the less

However - it did make less power than the Buschur so its not "all that" if you get my drift ?

 

In this case that would not work as the car went too lean with the Buschur unit and all the cry babies would have claimed the power came from the leaner a/f

Just my idea

Maybe next time I will try it your way

Anyway I do it - someone will complain - they always do

 

Not really true you know if the afr's get out of balance because of the exhaust that could easily skew results. Engine performance is also based on afr + timing keeping those the same its easier to tell what the VE enhancement would be with any said exhaust system.

Besides the test pipe differences the only real missing data from Al's post would be the calculated error. Since he ran so many tests it should be pretty easy to get a finite difference in hp between runs on the same exhaust and calculate the mean.

If he had a calculated error of say 10hp and the total hp gained on system A vs B was 15hp then you can establish that A will yield about 5hp.


Note:
I DO NOT expect Al to give me Lab Grade results after all its his time and effort. I appreciate his work.

 

^^I agree. A car can make 3-9 whp difference between pulls with no changes to it. I would say this is a good test. And as far as retuning, well you have to make the necessary adjustments for a part to work whether it is an exhaust or whatever. I think if you look at the two exhausts side by side and look at the numbers you can see everything looks in order. IMO that is.

 

If it is more restrictive than the Buschur exhaust and can make near the same power, then apparently, it IS all of that. Why do you keep contradicting yourself sir? "HKS is great thats why I recommend their products." "But they're not ALL THAT." Putting beer cans through exhausts? That is about the most absurd thing I have heard of so far. Simply brilliant. You make comments about "El Cheapo China Exhausts" yet compare exhaust performance by putting cans of Milwakee's Best through them.

 

My Ebay "crap" works just fine!

 

Word, mine too. While they argue over which is better, we can figure out how to spend the extra $500 bones we saved. Ha!