[BMWM4_SA]

Hi Guys

Stumbled across this video on youtube, racechip guys says that on stock tune by adding a downpipe their car yielded a 30whp gain, has any had similar experience ?

[mike@x-ph.com]

sounds very optimistic, but I cant argue with the data.

[chenry]

Race chip has a very creative and aggressive way of estimating gains at the crank. If you look at their wheel horsepower numbers (from most all of their videos) and then compare them to their estimated crank numbers you will discover the drive train loss percentage they use is one of the most aggressive you will find

Not saying anything one way or another about Race Chip - just something to be aware of

ps- love my catted CG Precision DS1 Catted DP paired with my MP Stage 2 Flash....

*Does it make beautiful sound and allow the turbo spool more freely? Yes
*Did it add some HP? Yes
*Did the DP give me 30 hp? No

[TupperBMW]

^ How many cel are your cats?

I have OEM downpipe in my BMW, but have 200 cel cats in my 911 (stock is 700 cel). They definitely enhance the sound, but I doubt they add more than a minuscule amount of power

[bm5bullit]

I can't say yet if it will be the same for my M340i but, they were worth 34 rwhp on my M5. Before and after on the dyno.

[GD1981]

optimized, a DP is good for about 20 whp

[mike@x-ph.com]

Originally Posted by GD1981

optimized, a DP is good for about 20 whp

20whp is a more reasonable number

[Unruly1]

When my car was completely stock it was making 14lbs of boost based on the factory boost gauge after I added a catless downpipe my car was making 17lbs not sure what that equates to for hp but it was definitely pulling harder

[mike@x-ph.com]

Originally Posted by Unruly1

When my car was completely stock it was making 14lbs of boost based on the factory boost gauge after I added a catless downpipe my car was making 17lbs not sure what that equates to for hp but it was definitely pulling harder

[TupperBMW]

Originally Posted by TupperBMW

^ How many cel are your cats?

I have OEM downpipe in my BMW, but have 200 cel cats in my 911 (stock is 700 cel). They definitely enhance the sound, but I doubt they add more than a minuscule amount of power

So, unless I'm wrong, the CG Precision dp are 200 cell per square inch cats

The AA dp are 400 cell per square inch.

So AA dp are more restrictive to gas flow than the CG precision. Looks like you'd get potentially better turbo spool with CG precision than AA

[mike@x-ph.com]

Originally Posted by TupperBMW

So, unless I'm wrong, the CG Precision dp are 200 cell per square inch cats

The AA dp are 400 cell per square inch.

So AA dp are more restrictive to gas flow than the CG precision. Looks like you'd get potentially better turbo spool with CG precision than AA

Please note more CEL does not necessarily mean less power. I have seen 400 CEL downpipes flow more air than 200 CEL.

From all the data I have seen, the Active Autowerke 400 CEL downpipe airflow is on par with all the top catted downpipes on the market.

[baturbo]

Originally Posted by mike@x-ph.com

From all the data I have seen, the Active Autowerke 400 CEL downpipe airflow is on par with all the top catted downpipes on the market.

Can you share some of this data?

Just ordered AA DP from you.

[mike@x-ph.com]

Originally Posted by baturbo

Can you share some of this data?

I just ordered AA DP from you.

Im currently overseas; I'll check back in 1 week once I'm back. But i know active autowerke posted a couple dynos and there are a few dynos posted by forum members

[abbike18]

AA uses the GESi 85200 cat. You can check out the specs on the GESi web page. Also go look up the price for just the cat core...you get what you pay for with stuff like that IMO.

https://gsportbygesi.com/high-perfor...tems-products/

In the X3 forum there's a member (dinan5m3) who has some dyno time booked. Going to run the 400 cel AA DP and a 200 cel side by side with a few different stage 1/2 tunes. I think he has it booked for next Friday. Could get some interesting data!

[G30M]

Originally Posted by Unruly1

When my car was completely stock it was making 14lbs of boost based on the factory boost gauge after I added a catless downpipe my car was making 17lbs not sure what that equates to for hp but it was definitely pulling harder

[Fronttwelv]

I can't imagine going through all the trouble for a down pipe especially with the new ecus. They're a PITA to install and unless you live in SOCAL the tune is a pretty big risk.
If you go catless you need the tune, and it will smell.
If you go cheap catted it will still smell, you need the tune and you just spent an extra half stack.
If you go AA or other GESi catted you don't need the tune and it won't stink but why do a downpipe if you aren't going to add a tune, it won't do anything.
Just get a nice exhaust and a piggy until the tunes become more accessible.

[Randy Johnson]

Originally Posted by Fronttwelv

I can't imagine going through all the trouble for a down pipe especially with the new ecus. They're a PITA to install and unless you live in SOCAL the tune is a pretty big risk.
If you go catless you need the tune, and it will smell.
If you go cheap catted it will still smell, you need the tune and you just spent an extra half stack.
If you go AA or other GESi catted you don't need the tune and it won't stink but why do a downpipe if you aren't going to add a tune, it won't do anything.
Just get a nice exhaust and a piggy until the tunes become more accessible.

Downpipe actually gives you a deeper/louder sound and a decent bump in power even without a tune. Pretty good bang for the buck IMO.

[mike@x-ph.com]

Originally Posted by Fronttwelv

I can't imagine going through all the trouble for a down pipe especially with the new ecus. They're a PITA to install and unless you live in SOCAL the tune is a pretty big risk.
If you go catless you need the tune, and it will smell.
If you go cheap catted it will still smell, you need the tune and you just spent an extra half stack.
If you go AA or other GESi catted you don't need the tune and it won't stink but why do a downpipe if you aren't going to add a tune, it won't do anything.
Just get a nice exhaust and a piggy until the tunes become more accessible.

Originally Posted by Randy Johnson

Downpipe actually gives you a deeper/louder sound and a decent bump in power even without a tune. Pretty good bang for the buck IMO.

+1
it all depends on your goals.

if the customer is looking for a stock++ sound, the downpipe is an excellent choice. plus the added benefit of added power.

[GA/\/\/\/\A_CT]

Originally Posted by mike@x-ph.com

+1
it all depends on your goals.

if the customer is looking for a stock++ sound, the downpipe is an excellent choice. plus the added benefit of added power.

I agree with Mike and Randy.

There really isn’t a downside to the AA DP, but cost. It’s a great value in terms of great, better power/response, and it can be a standalone mod. I have bought 2 from Mike and currently have one on an untuned m340ix. I would do it all over again.

Great mod.

[m240nj]

Originally Posted by GA/\/\/\/\A_CT

I agree with Mike and Randy.

There really isn’t a downside to the AA DP, but cost. It’s a great value in terms of great, better power/response, and it can be a standalone mod. I have bought 2 from Mike and currently have one on an untuned m340ix. I would do it all over again.

Great mod.

Just installed one on my untuned 340 as well and agree with all your points. Solid upgrade and the car definitely feels faster. Also purchased from Mike which was a seamless transaction.

[RCKYMTN M34OI]

Originally Posted by mike@x-ph.com

Please note more CEL does not necessarily mean less power. I have seen 400 CEL downpipes flow more air than 200 CEL.

From all the data I have seen, the Active Autowerke 400 CEL downpipe airflow is on par with all the top catted downpipes on the market.

I can confirm this with my anecdotal experience. I've had 2 M340s .One with the CG DS1 and now i have one with the AA downpipe. Can't really say i can tell the difference between the 2. Both give better throttle response and slight seat of the pants performance bump. Both have great sound and neither one threw a CEL. With the price point of the CG DS1 it's a great option IMO.
I've got one for sale in the marketplace if anyone is interested
https://g20.bimmerpost.com/forums/sh....php?t=2094392

[mike@x-ph.com]

Originally Posted by RCKYMTN M34OI

I can confirm this with my anecdotal experience. I've had 2 M340s .One with the CG DS1 and now i have one with the AA downpipe. Can't really say i can tell the difference between the 2. Both give better throttle response and slight seat of the pants performance bump. Both have great sound and neither one threw a CEL. With the price point of the CG DS1 it's a great option IMO.
I've got one for sale in the marketplace if anyone is interested
https://g20.bimmerpost.com/forums/sh....php?t=2094392