Perrin Exhaust claims, fishy????

[tennisfreak]

So tonight I was planning on making my exhaust purchase and had it narrowed down between two choices, the borla or the perrin (non resonated).

I was looking on Perrins site and noticed I could also get a front pipe as well. Perrin claimed roughly +7hp for the catback and then another 5+ for the front pipe as well. I was thinking "sweet, maybe I should get both".

Then I looked at the dyno charts on Perrins website for both.
The dyno charts did not look right. I was seeing the same gain on both dyno charts.

Their catback dyno is a comparison of stock exhaust and their exhaust showing 165hp for stock vs 172hp for theirs.


Their front pipe dyno is a comparison of their catback only vs their catback plus the front pipe. Their catback shows 167hp and their catback plus front pipe shows 172.

Why are the hp numbers and graphs almost identical between the two??
Maybe I am misunderstanding something so if anyone from Perrin sees this could you please comment?

[Chewie4299]

Dynos were done at different times under different conditions.

There is a margin of error.

You're talking about a difference of 5 peak HP between the two "catback runs". Those to things can easily cause that.

[86_ZN6]

Different day different results

[Apoc]

They explain the results in Jeff's blog

http://blog.perrinperformance.com/br...n-and-proving/

[SmsAlSuwaidi]

Perrin........LOL

[Sony]

Originally Posted by SmsAlSuwaidi

Perrin........LOL

What???

[Dizz1e]

Originally Posted by Sony

What???

I concur. Perrin is one of the best exhaust out there. Plus... MURICA'

[2forme]

Also keep in mind they use a dynapack. It's a dyno that measures horsepower a bit differently because it doesn't account for rolling resistance or load. They are usually called "sales" dynos because of their generous nature. Great for tuning, though because they give very consistent results.

[Calum]

Originally Posted by tennisfreak

So tonight I was planning on making my exhaust purchase and had it narrowed down between two choices, the borla or the perrin (non resonated).

I was looking on Perrins site and noticed I could also get a front pipe as well. Perrin claimed roughly +7hp for the catback and then another 5+ for the front pipe as well. I was thinking "sweet, maybe I should get both".

Then I looked at the dyno charts on Perrins website for both.
The dyno charts did not look right. I was seeing the same gain on both dyno charts.

Their catback dyno is a comparison of stock exhaust and their exhaust showing 165hp for stock vs 172hp for theirs.


Their front pipe dyno is a comparison of their catback only vs their catback plus the front pipe. Their catback shows 167hp and their catback plus front pipe shows 172.

Why are the hp numbers and graphs almost identical between the two??
Maybe I am misunderstanding something so if anyone from Perrin sees this could you please comment?

The fact that they are showing a dyno of the front pipe with the cat back is pretty good. It shows they aren't doing 'ricer math' with the number. I'd look at nameless myself, but I don't see anything wrong with those dyno graphs.

[DarkSunrise]

Originally Posted by Apoc

They explain the results in Jeff's blog

http://blog.perrinperformance.com/br...n-and-proving/

Yep, they address this issue in their blog:

This part was built the follow day after the first test, so the car has sat for about 12 hours. We did another set of 4 base runs before installing the front pipe. The first thing I noticed (before installing the prototype front pipe) is that it had lost some HP. This day was hotter than the last by about 10F, and based on some of other findings,I think the ECU has a limit of increased TQ or load.

These results were very repeatable. We did about 5 more runs all showing the same 5-8 WHP. This dyno session was done with our catless Front pipe, and a test with the catted version will follow soon. Overall this is a great sign that this part makes HP, but it also might be showing we may be hitting a limit in the ECU that won’t allow more power. Commonly, ECU’s have limits like load limits, or torque limits to help control horsepower. This sounds silly, but its a way for Subaru/Toyota to protect their engines from making too much Torque/power. Remember back in the old days where your car was faster when it was cold out? ECU manufactures put in load and TQ limits to help make the car the same power all the time.

If you're worried the Perrin CBE doesn't make the power it claims, here's a 3rd party test from DSport Mag, should help put your mind at ease:

[tennisfreak]

Thanks for the updates.

The blog helps explain a lot and so does the DSport Mag article.

So now I will ask this, if the blog is correct and the ECU is in fact limiting tourque and hp, does this mean that no matter what mods I do to my car I will hit a wall unless I get a tune?

[Huehuecoyotl]

The stuff makes power, its design is dyno driven and dyno proven

what more can I tell you?

Not every shop making a system can say that. I can run anything I want to make power. There just isnt any other option that makes sense from a design standpoint for me, so this remains our holy grail...

Originally Posted by tennisfreak

Thanks for the updates.

The blog helps explain a lot and so does the DSport Mag article.

So now I will ask this, if the blog is correct and the ECU is in fact limiting tourque and hp, does this mean that no matter what mods I do to my car I will hit a wall unless I get a tune?

yes, getting a tune will unlock power adding an exhaust alone wont

[Foobar]

Originally Posted by tennisfreak

Thanks for the updates.

The blog helps explain a lot and so does the DSport Mag article.

So now I will ask this, if the blog is correct and the ECU is in fact limiting tourque and hp, does this mean that no matter what mods I do to my car I will hit a wall unless I get a tune?

That's my understanding. The ECUTek flash removes the load limits, speed limits, raises redline limit, etc. Without the tune, you aren't getting the most out of your mods.

[PERRIN_Jeff]

Ya sometimes the dyno graphs can be confusing because they were not all done at the same time. This is a good example of that. We did the catback results one day, (very repeatable), then the next did the front pipe stuff.

The other slightly confusuing thing is the numbers you see in the boxes, this just represents where the cursor is at on the software. You can see that we didn't compare the peak power on each run, but rather areas we thought were important.

What is boils down to is the variance in HP on the car. We have see this be a huge factor for showing dyno results on things. In fact I experienced this last weekend tuning. I was making 193 WHP on our NA car and the next day it was down about 10 HP. At least until the engine got about 20 pulls into the day and got fully warmed up. Oil temps are key to making power. HP is lost until the oil gets to about 80-90C, then then engine is good and happy. Then it seems to loose power as oil temps go above 105C. Here is a dyno graph showing the huge variance in HP as a car that is fully warmed up, goes through about 14 pulls on the dyno.



More info about why you want an oil cooler can be found here!

If you have more questions about this, let us know! Also check out the blog, there is a BRZ section that has more info as well.