P5 Dyno - Aem Ram & Sportexhaust

[Woody]

Yippy Skippy!

I did a re-dyno of my P5 after my Mazda Sport Exhaust. The first dyno below shows baseline (stock) against redyno with both AEM Short RAM, and Sport Exhaust installed...

As you can see with the 2 mods I picked up almost 5 peak hp gain, the best increase looks to be about 9 hp.


This second graph shows a dyno with my AEM Short RAM installed, against the AEM S. RAM after the Sportexhaust install. The indea here was to show the impact of the exhaust install.

So from this, it looks like the exhaust gave me an additional 3+ wheel hp.

I'm happy witht the results. By the way, my car is a stick shift, and all numbers are wheel hp, not crank hp.

- Woody

 

[ZoomZoomH]

oooooooooooooh nice results!!!

I assume the dyno was ran in 3rd gear right? or was it 4th?

finally somebody has given us solid proof that Mazdaspeed muffler does give us some minor gains, even if it's just an axle-back bolt-on

thanks for your work Woody!

 

[[Cruzer]]

Mazdaspeed muffler does give us some minor gains, even if it's just an axle-back bolt-on

So woody "is" yours an axle back??? if so then I really can't wait until monday when mine comes in...

 

[Woody]

ZOOMZOOM -

I just called them - they take the gear that is closest to 1 to 1 ratio - in my case they took 3rd gear.

CRUZER,

Yes. Mine is the "axle-back" that Mazda puts out, and is listed as an accessory in their brochure. They call it the Sport Exhaust, but some people refer to it as the Mazdaspeed exhaust because it has Mazdaspeed etched on the tailpipe. Just don't expect to feel a lot of improvement - otherwise you will be disappointed. My butt meter told me about 3 hp+ and as it turned out that was in the ball-park.

This dyno also shows that Mazda customer service gave me the correct info when I asked about hp increase. They said 3 to 4 hp, and this looks correct.

- Woody

 

[Antoine]

Awesome...thanks for sharing the dyno charts Woody!

Nothing like a great dyno run to cut the BS.

 

[Woody]

ANTIONE,

Well, yeah. I've said this before, but I can't beleive so many guys put money into mods, but then don't dyno them to measure what they have done.

But I guess Dyno's are not accessable everywhere, so I can't be too critical.

Now I need to decide if I want to go ahead with the cams. That's a hard one - I can't decide.

- Woody

 

[Bumble G]

what about torque #'s?

any plots of it

 

[Woody]

Bumble -

No torque. But I can tell you a dyno meter only measeure torque, and then infers hp from that. I'd been meaning to ask my dyno guys about why they don't display torque curve, but I keep forgeting. But as I say hp vs. torque on a dynometer is only playing with numbers anyway.

 

[herarety]

How about HP vs. RPM ?

Btw..am I correct that the 'axle-back' exhaust is only the muffler, and still uses stock piping?

 

[ZoomZoomH]

what about torque #'s?

any plots of it

well, since a dyno derives HP from measured torque rating, that means with some simple algebra, you can convert HP back to torque.

here's the formula from HP to torque:

Horsepower = torque x rpm / 5252

and after some algebra, we have:

torque = HP x 5252 / rpm

this formula only works in HP and ft/lb unit conversion.

here's a good page for explaining HP/torque relationship:

http://www.revsearch.com/dynamometer/torque_vs_horsepower.html

and as for getting the RPMs, since this dyno was done in 3rd gear, as stated by Woody, a little bit of math would also convert the shown MPH into its proper RPM in 3rd gear. I don't have the equation between gear ratio/speed/rpm, so someone will have to calculate that for us

 

[Woody]

herarety,

The Mazda Sport Exhaust is the tail pipe, muffler, and about 2 1/2 ' of additional pipe - called an axle-back.

Other companys like Racing-beat, and Bosal produce longer pipes for our cars, called cat-backs - but IMHO don't deliver much bigger (if any) bump in performance than the Mazda axle-back (read sport exhaust).

- Woody

 

[your mom]

3 whp from a muffler? Not bad1 the RB cat back gives 4.5 whp and it cost $450.

 

[Kooldino]

ZOOMZOOM -

I just called them - they take the gear that is closest to 1 to 1 ratio - in my case they took 3rd gear.

- Woody

You must have an auto then. BC if you had a manual, 4th is the closest to 1:1, and that's a .97 difference.

What kind of dyno was it on? Why does it show MPH instead of RPM? I hate that! :-(

So the top was NO MODS and the bottom was intake+exhaust?

I assume GREEN is HP and RED is TQ?

Also, I'm not seeing the HP gains...maybe I'm on crack. I see TQ gains of 1.5...

 

[Kooldino]

ooooooh, i think i see what you did here. each dyno sheet just shows the HP curves of two different "settings" on the car.

First one is
AEM+exhaust vs stock

second is
AEM vs AEM+exhaust

Right?

And there's no TQ numbers involved anywhere?

 

[your mom]

i think those plots are mixed up!
Both exhaust and AEM = 4.8 whp
exhaust only = 3.3 whp
so the AEM only = 1.5 whp

I have NEVEr heard of a muffler give 3.3 whp. Usually complete catback that cost over $400 give between 3-5 whp, not just a muffler.

Intakes usually give about 4-5 whp.

 

[Antoine]

I was always under the impression exhaust system upgrades produce larger gains than intake upgrades (most of the time) especially on a F/I engine.

Although in some cases not by much.

 

[Woody]

Yips!

I'm not sure why I was not getting notifications but it looks like there have been some recent questions - I'll try and answer what I can:

KOOLIDINO -

I beleive the dyno was a "Dyno Jet" but I can't swear to it.

No graph for torque, and I explained this earlier in the thread.

Just take a closer look at what I say before each dyno graphic - it explains what it is.

YOURMOM -

I was skeptical that I would get more than a couple hp out of the sport exhaust. My butt meter said 3 to 4, and the dyno test agreed with this. From MY results anyway, it looks like I got a little more from exhaust, than intake. Actaully the dyno tech said that there was a bigger COMPENSATION done by the Dyno equipment after the run with the muffler install/run - because it produced a bigger bump - which brought the muffler gains down. So actaully if the dyno equipment OVER compensated the hp increse from the muffler would be even more.

- Woody

 

[Woody]

KOOLDINO -

No I have the 5 speed manual. You are right it looks like 4th is closest to 1 to 1 ratio. But I think we can assume they know what they are doing - they dyno cars almost non-stop.

- Woody

 

[your mom]

Thanks for the response.
I am curious how much HP emoving the 2nd cat gives. Anyone knows? How much would the Bosal Fedral catback give since it is bigger and removes the 2nd cat?

 

[Esteban Toledo]

I just found this thread. So, here's a bump for those who haven't.