How much horsepower are you getting from your exhaust

[jayman33]

We went from 387 baseline to 457 SAE with just the ARH exhaust system (no cats) and JLT intake.

Sponsored

 

[OppoLock]

Fuuuuaaaaaark^

 

[yjack]

Feels like 1000 HP gain to me due to the sound.

 

[cush]

Fact - multiple catbacks have been dynoed, same day, same dyno, back to back. AVG RWHP gains have been 1-3. Nothing more. This is across about 4 different catbacks on a bonestock car with resonator in place.

Now when you do long tubes, CAI and tune, the numbers have been above 40RWHP from a peak number standpoint. Area under the curve you ask? 50-55RWHP and higher in the mid-range.

If the "resonator" was in place then you were not looking at a catback.... The resonator is the box under the drive shaft, did you mean to say the cats were in place?

 

[Dave2013M3]

I think headers by themselves are probably only worth about 12-15rwhp if you go the catted route without a tune. Headers give you more than this if you go the non catted route, then you are in the 20-25rwhp range. What I would like to see is not a dyno done but a real life run down the 1320 with a bone stock car than a modded car and see what the MPH is at the end of the run.

The catbacks are for sound, nothing more.

Dave

 

[DeepImpactGTny]

As much as stick on fender vents.

 

[Grimace427]

I think headers by themselves are probably only worth about 12-15rwhp if you go the catted route without a tune. Headers give you more than this if you go the non catted route, then you are in the 20-25rwhp range. What I would like to see is not a dyno done but a real life run down the 1320 with a bone stock car than a modded car and see what the MPH is at the end of the run.

The catbacks are for sound, nothing more.

Dave

The difference between catted headers and off-road headers isn't that much in terms of power. The cats that come with headers are very high-flow compared to stock, to the point that they don't really do much emissions-wise other than cut down on noise and smell somewhat.

 

[Dave2013M3]

The difference between catted headers and off-road headers isn't that much in terms of power. The cats that come with headers are very high-flow compared to stock, to the point that they don't really do much emissions-wise other than cut down on noise and smell somewhat.

I saw a test that catted headers were 8rwhp less than non catted headers. I'm all for high flow cats don't get me wrong. The cats do actually do some scrubbing but since they are farther down stream there is less turbulence in the exhaust path but they don't get to temp quick enough.

This still comes to the point that the headers by themselves are probably really only worth 12-15rwhp as removing the cats themselves ala MAK testpipes have shown 12-13rwhp gain from some members.

Dave

 

[thehunterooo]

My Outlaws made a big impact I can avg about 41 mpg. 32 is cute though.....

Wow I must say 41 is pretty good, I am semi jelly.

 

[VTECSAUCE]

My Outlaws made a big impact I can avg about 41 mpg. 32 is cute though.....

not sure if serious...:shrug:

 

[krahooligan]

well. I have a 3 inch cat back. and they open up to a 4.5 inch tip. so taking the rotational effects of the sun and multiplying this by 3 for the cat back we get 100HP gains. depending on whether or not there is ample amounts of swamp gas in the air. then you will have more or less depending on the leca scale.
so yeah. I made about 100hp gains.

 

[Guard5.0]

Keep in mind these are dyno numbers, but it was same dyno same day. ARH LT's, off-road with H pipe with full ARH exhaust with absolutely no tune showed 29 rwhp gain (371 to 400). So there is something to the LT's besides noise. The reason for no tune was that the SC install was started next (where the tune came from) and there was just curiosity over what kind of gains could be had.
On a side note, after all of my mods I'm getting 56mpg/hwy and 49mpg/city. The highest number I had seen in this thread was 55 so you know how that works... and my dad can beat up your dad!

 

[Brent302]

not sure if serious...:shrug:

Def not lol

 

[thehunterooo]

well. I have a 3 inch cat back. and they open up to a 4.5 inch tip. so taking the rotational effects of the sun and multiplying this by 3 for the cat back we get 100HP gains. depending on whether or not there is ample amounts of swamp gas in the air. then you will have more or less depending on the leca scale.
so yeah. I made about 100hp gains.

Only a 100HP gain? That's not very good.

 

[Brent302]

Only a 100HP gain? That's not very good.

Sponsored