What is the most power anyone has made with a ATP GT30 Turbine Housing?

[cld12pk2go]

So I am currently somewhere around 420whp or so according to VDyno, and I am currently looking to do some debottlenecking of my intake/exhaust.

I just found that even though my current Treadstone TR11 IC is much better from a delta T and delta P perspective, I am still not getting much (if any) additional massflow after replacing my CXRacing IC0035.

I am guessing that my exhaust must be severely choked up, which means either the ATP GT30 0.55 A/R turbine housing or my stock CBE is a huge restriction.

I am pretty much going to get a Cobb CBE in the near future, but I am just curious what other people have managed to make with the ATP turbine housing to get a feel of if it might be my main restriction or not...

It would obviously not be cheap/easy to upgrade to another turbine housing as it would require a new EM/DP...

[Chimmike]

What exhaust are you running?

I've done 420whp (per vdyno) on the ATP IWG housing, and that's on stock CBE. Frankly, I think the ATP IWG housing will flow 500whp. I'm converting to EWG myself but welding the flapper, and I'll probably take a flap wheel to the inside of the ATP housing as best I can to port it out.

[cld12pk2go]

Originally Posted by chimmike What exhaust are you running? I've done 420whp (per vdyno) on the ATP IWG housing, and that's on stock CBE. Frankly, I think the ATP IWG housing will flow 500whp. I'm converting to EWG myself but welding the flapper, and I'll probably take a flap wheel to the inside of the ATP housing as best I can to port it out.

I am using the Stock CBE and a well ported ATP WG hole.

It is interesting that you are at approx the same power level as I am. Have you tried to push beyond 420whp?

[superskaterxes]

my last actual dyno was 430whp with AWD but logs show i was making 15-20 more whp before i finally blew.

[NJSPEED3]

Didn't dturboman make over 500whp with that turbo?

@dturboman

Sent from my XT894 using Tapatalk 2

[cld12pk2go]

Originally Posted by superskaterxes my last actual dyno was 430whp with AWD but logs show i was making 15-20 more whp before i finally blew.

Where those number with the GT35 turbine housing or a GT30? What CBE?

[helmetface]

Ditch the COBB CBE, buy CNT!

Less than half the price..flows great..sounds great..

[cld12pk2go]

Originally Posted by helmetfail Ditch the COBB CBE, buy CNT! Less than half the price..flows great..sounds great..

My understanding is the CNT is pretty loud though...right?

I need quiet, which only leaves Cobb and Racingbeat unless I am missing something and I do not like the Racingbeat design...

[helmetface]

Originally Posted by cld12pk2go My understanding is the CNT is pretty loud though...right? I need quiet, which only leaves Cobb and Racingbeat unless I am missing something and I do not like the Racingbeat design...

I agree about the RacingBeat but I think it sounds mean.

My CNT TBE catless isn't too loud actually..I mean when you get on it..any 3" exhaust is going to howl, but when I'm cruising it's pretty quiet and there is very little drone.

[cld12pk2go]

Originally Posted by helmetfail I agree about the RacingBeat but I think it sounds mean. My CNT TBE catless isn't too loud actually..I mean when you get on it..any 3" exhaust is going to howl, but when I'm cruising it's pretty quiet and there is very little drone.

Do you have a feel for the sound difference between the stock CBE and the CNT? I am mostly concerned about idle and low throttle (can't wake up the neighbors starting the car)...

[Roddiy]

Originally Posted by cld12pk2go I am using the Stock CBE and a well ported ATP WG hole. It is interesting that you are at approx the same power level as I am. Have you tried to push beyond 420whp?

CBE is definetely a restriction at those power levels.

@atvfreek always said that even near 300whp it starts becoming a restriction. At 420 I'd say you have AT LEAST 20whp to gain from a true 3" exhaust.



P.S. UR CBE Is the shit.

[helmetface]

Originally Posted by cld12pk2go Do you have a feel for the sound difference between the stock CBE and the CNT? I am mostly concerned about idle and low throttle (can't wake up the neighbors starting the car)...

When you first turn on the car, cold start and the RPM's are high there is a substantial difference between stock CBE and CNT. After that ~6 second window it's at a very reasonable level.

After the exhaust settles in, it's going to be a little louder than stock, begging the size difference, but I truly don't feel it's "much" louder at low throttle and barely louder at idle.

I park my car directly under a 3 family building, who's tenants have their windows open all night and I've not received one complaint in the ~10 or so months I've had my exhaust done up like so. I hang with some of them, those with kids and no one has said anything. So I can't think it's much worse.

But again, the initial cold start is a bit vicious, afterwards it's reasonable, I feel.

Originally Posted by Roddiy P.S. UR CBE Is the shit.

UR was what I was thinking of when we spoke of RacingBeat Cld12pack. It's a good sound, although I can't testify for it's idle and low throttle decibel rating.

[Roddiy]

Originally Posted by helmetfail When you first turn on the car, cold start and the RPM's are high there is a substantial difference between stock CBE and CNT. After that ~6 second window it's at a very reasonable level. After the exhaust settles in, it's going to be a little louder than stock, begging the size difference, but I truly don't feel it's "much" louder at low throttle and barely louder at idle. I park my car directly under a 3 family building, who's tenants have their windows open all night and I've not received one complaint in the ~10 or so months I've had my exhaust done up like so. I hang with some of them, those with kids and no one has said anything. So I can't think it's much worse. But again, the initial cold start is a bit vicious, afterwards it's reasonable, I feel. UR was what I was thinking of when we spoke of RacingBeat Cld12pack. It's a good sound, although I can't testify for it's idle and low throttle decibel rating.

I have the CBE though I have both cats on, its very low. I've also heard it on a Catless PU and at Idle it's pretty quiet, though it obviously gets real loud as soon as you step on it.

[Realgib3]

CBE is not a problem on a 3. Period.

My last Vdyno with my ATP X76 was 463whp @27psi, stock em, stock catback and that peak whp was at redline, so nothing was choked up at all.

Also, already made 440+ on my 6466 @18.5psi, stock catback as well.

IMO, the turbo itself is the biggest restriction here... but I'm one of the only people on here who likes big turbos on these cars, so I know that won't be a populaar opinion.

[Lex]

There are 2 ways to increased massflow:

1. Increase the VE of the motor by reducing pumping losses so that you flow more at the same pressure ratio - given the compressor can do it.

2. Increase the pressure ratio (ie boost). This requires to spin the turbine faster. This requires a larger pressure differential across the turbine. This requires less backpressure past the turbine and less pressure drop across the manifold ... or just more exhaust flow altogether.

Are you maxing out WGDC? If not, you can spin it faster but make sure you compensate with cooling as the compressor is losing efficiency and introducing heat.

If WGDC is maxed out I would look at either decreasing back pressure post or pre turbine. This will give you more WGDC headroom.

If you're after increasing the VE of the motor and the compressor CAN flow more then I'd look at the largest pressure drops from intake to exhaust and I would look at how to increase air density before and after the compressor.

[cld12pk2go]

Originally Posted by Realgib3 CBE is not a problem on a 3. Period. My last Vdyno with my ATP X76 was 463whp @27psi, stock em, stock catback and that peak whp was at redline, so nothing was choked up at all. Also, already made 440+ on my 6466 @18.5psi, stock catback as well. IMO, the turbo itself is the biggest restriction here... but I'm one of the only people on here who likes big turbos on these cars, so I know that won't be a populaar opinion.

Turbo meaning compressor side or turbine side?

It would seem that the compressor side should be capable of ~500whp without too much issue from the map?

[Chimmike]

Originally Posted by cld12pk2go I am using the Stock CBE and a well ported ATP WG hole. It is interesting that you are at approx the same power level as I am. Have you tried to push beyond 420whp?

Haven't been able to push more than 24psi, think I have a leak in the vac line to the IWG.

Frankly from what I've gathered in research and other opinions, stock CBE is holding us back at 400+whp

After reading realgib3, now I wonder.

regardless, I'll fab up a 3" cat back after my motor build, if for nothing else than some nice sound. I would expect to see maybe 20whp from it though. Especially since by that time I'll be on aftermarket EM and EWG.

[cld12pk2go]

Originally Posted by Lex There are 2 ways to increased massflow: 1. Increase the VE of the motor by reducing pumping losses so that you flow more at the same pressure ratio - given the compressor can do it. 2. Increase the pressure ratio (ie boost). This requires to spin the turbine faster. This requires a larger pressure differential across the turbine. This requires less backpressure past the turbine and less pressure drop across the manifold ... or just more exhaust flow altogether. Are you maxing out WGDC? If not, you can spin it faster but make sure you compensate with cooling as the compressor is losing efficiency and introducing heat. If WGDC is maxed out I would look at either decreasing back pressure post or pre turbine. This will give you more WGDC headroom. If you're after increasing the VE of the motor and the compressor CAN flow more then I'd look at the largest pressure drops from intake to exhaust and I would look at how to increase air density before and after the compressor.

You are pretty much seeing it how I am. I am attacking the known VE issues in order on the intake/exhaust side. The IC was an obvious one.

I am currently maxing out my WGDC (10 PSI spring with max preload). However, I expected to get another 1-2 PSI of boost with the decrease in IC DP. Since this didn't happen, I am thinking the exhaust must be choked up...

My BATs are under ambient so no issue with heat load.

[chuckms6]

IMO a custom dp with a $80 qtp cutout is better then a $800+ cbe, but that's just me.

Tapatalking

[Lex]

Originally Posted by cld12pk2go You are pretty much seeing it how I am. I am attacking the known VE issues in order on the intake/exhaust side. The IC was an obvious one. I am currently maxing out my WGDC (10 PSI spring with max preload). However, I expected to get another 1-2 PSI of boost with the decrease in IC DP. Since this didn't happen, I am thinking the exhaust must be choked up... My BATs are under ambient so no issue with heat load.

You probably will get that 1-2psi from adding a catback .... and a stiffer WGDC spring The flapper is probably pushed open by the pressure differential across the turbine.

[Chimmike]

Originally Posted by chuckms6 IMO a custom dp with a $80 qtp cutout is better then a $800+ cbe, but that's just me. Tapatalking

Cld12pk is a pretty resourceful guy. I bet he could fab his own like I'm doing for sub-$200, in full stainless

[EdgeAutosport.com]

I dont understand why no one has done a 4"cbe yet. Before we all say thats going to to be too loud and what not I think some of the big turbo guys would really benefit going 4". Its easy power to be had just curious why no one has done it.

If my car was going to be kept that was next on the list to free up some HP

[helmetface]

Just gunna leave this here...

CNT RACING 07-08 Mazdaspeed 3 catback Exhaust (76mm piping) (stainless tips)

For the non-fabbers

You know what they say.."Less time Fabbin' - more time Fappin'"

Originally Posted by eric@edgeautosport I dont understand why no one has done a 4"cbe yet. Before we all say thats going to to be too loud and what not I think some of the big turbo guys would really benefit going 4". Its easy power to be had just curious why no one has done it. If my car was going to be kept that was next on the list to free up some HP

You should have done it and incorporated a bucket into the resonator design

[cld12pk2go]

Originally Posted by Lex You probably will get that 1-2psi from adding a catback .... and a stiffer WGDC spring The flapper is probably pushed open by the pressure differential across the turbine.

That is what I am thinking as well from the CBE...I could be wrong like I was with the IC, which I thought would free up another 2 PSI...

I have the 14 PSI WGA in my workshop as ATP sent me the wrong one initially, it is just a royal PITA to install it (will have to pretty much pull DP and unbolt turbo from EM...I might eventually give in and do it though...

Originally Posted by chimmike Cld12pk is a pretty resourceful guy. I bet he could fab his own like I'm doing for sub-$200, in full stainless

At this point, I would happily pay more for something of top notch quality as my time has a lot of value these days.

I have been dithering on the CNT vs Cobb CBE for a few months thinking that if the CNT is too loud I can just add an additional straight through resonator to tone it down but mostly I think I would likely be better off with paying more for the known quantity in the quite Cobb CBE.

[EdgeAutosport.com]

@helmetfail the funny thing is I found a "bucket style muffler" I was going to use on that setup lol

[cld12pk2go]

Originally Posted by eric@edgeautosport I dont understand why no one has done a 4"cbe yet.

Build it and they will come...lol

[Chimmike]

I've heard good things about the Vibrant cbe.

[themytb]

My .02- on just a bnr s3 I went from slight tire squeaking to traction loss on third gear datalogs changing only stock cbe to cnt cbe.
I am single catted and really like my cnt cbe, I had to be talked into it because I was afraid it would sound ricey, It does not. Decently quiet at idle/low throttle, nice deep tone when on her. I have gotten a few good comments from american muscle guys that I know.
Also for the cold starts, just tap the throttle right at start up and she just purrs a tiny bit heavier than normal idle.

[cld12pk2go]

So my cheap side won out as I couldn't ignore $339 shipped.

CNT CBE on order.

If it is too loud, I will just hack in one of these:

Vibrant Performance 1142 - Vibrant Performance Ultra-Quiet Resonators - Overview - SummitRacing.com

Dynomax Performance 17267 - Walker Ultra Flo SS Mufflers - Overview - SummitRacing.com

Hopefully, it arrives by next Friday so I can do more testing.

[Jh8909]

The vibrant ultra quiet resonator is no joke. Does exactly what it says. I have it on my 3" catback and a very nice deep tone to it while not that loud.

[driver311]

I have a magnaflow hf 3in cat paired to my cs cbe and my car is very tame sounding. I love it and at wot it sounds like pure sex. Zlatans car with just catless long dp sounds louder than my car. I like mine being quiet under wot. I think the cs is one of the best options for this car at 80mm also.

Ps. On the topic of whats the potential of the atp back half. I think 480-500whp is obtainable but with some porting/reshaping of where it bolts to the mani 525-550whp is doable. Ive seen the dyno graphs/matched with vd maps and traps to back it up. Pretty impressive for a bolt on turbo. Evo owners are hitting 600-650whp with atp bolt on turbos. good stuff

[Etipp98]

Can't really beat the CNT even if it was $500...

[86AmishMs3]

I think kmac is atp hotside right? He's at like 500whp, then there's that tranny kissing guy, joel. He made nearly 500. Dturboman also made 500whp realm on VD.

Me personally I'm keeping it conservative. 22-23psi. I know when I was stock turbo I saw a 4-6g/s improvement from just a catback. People love to say a catback does nothing...but every little bit will help. I like Eric's idea...but just make a 3.5" exhaust downpipe back.

Did you port the turbine housing at all while you were doing the flapper. I definitely ported mine and i'm sure it helps some (that hump at the wastegate seemed like a restriction)....and I'm sure it helped create creep issues I was having in the beginning.

[Ziggo]

IMO the biggest restriction is the .55 A/R housing but at your power levels that stock cbe is probably becoming an issue.

I am excited to see results on TS setups with a fat A/R housings, .82 or bigger.Sshouldn't lose much spool going from .55 to .82 T3 divided and it should help the top end considerably.

[rfinkle2]

Originally Posted by chimmike What exhaust are you running? I've done 420whp (per vdyno) on the ATP IWG housing, and that's on stock CBE. Frankly, I think the ATP IWG housing will flow 500whp. I'm converting to EWG myself but welding the flapper, and I'll probably take a flap wheel to the inside of the ATP housing as best I can to port it out.

Alternative to welding the flapper to go EWG.

Sorry for the intrusion cld12pk. Good luck with your exhaust.

Adjustable IWG Bracket - Short

[cld12pk2go]

Originally Posted by 86azms3 Did you port the turbine housing at all while you were doing the flapper. I definitely ported mine and i'm sure it helps some (that hump at the wastegate seemed like a restriction)....and I'm sure it helped create creep issues I was having in the beginning.

You can see all of the porting work in post 1 here:

http://www.mazdaspeedforum.org/forum/foru...1-build-94543/

Originally Posted by Ziggo IMO the biggest restriction is the .55 A/R housing but at your power levels that stock cbe is probably becoming an issue. I am excited to see results on TS setups with a fat A/R housings, .82 or bigger.Sshouldn't lose much spool going from .55 to .82 T3 divided and it should help the top end considerably.

I guess we will find out in the next 2 weeks as I get the new CBE install and test...

It should be an interesting data point.

I will probably be tempted to go T3 0.82 A/R turbine housing if the CBE doesn't seem to help, but honestly I don't think I can justify the cost of a new EM/turbine housing/DP/WG...

[atvfreek]

I believe you will get a nice gain from the CBE. Especially if you have your wgdc maxed. Each car that I've tuned that was close to or above 300whp we needed to lower wgdc to maintain boost targets.

[mzr0818]

Originally Posted by driver311 I have a magnaflow hf 3in cat paired to my cs cbe and my car is very tame sounding. I love it and at wot it sounds like pure sex. Zlatans car with just catless long dp sounds louder than my car. I like mine being quiet under wot. I think the cs is one of the best options for this car at 80mm also. Ps. On the topic of whats the potential of the atp back half. I think 480-500whp is obtainable but with some porting/reshaping of where it bolts to the mani 525-550whp is doable. Ive seen the dyno graphs/matched with vd maps and traps to back it up. Pretty impressive for a bolt on turbo. Evo owners are hitting 600-650whp with atp bolt on turbos. good stuff

Magnaflow is the best noise, not to steal thread or divert from topic.

[Chimmike]

Originally Posted by rfinkle2 Alternative to welding the flapper to go EWG. Sorry for the intrusion cld12pk. Good luck with your exhaust. Adjustable IWG Bracket - Short

I might potentially give this a try. I do have the Ni55 rod to properly weld the cast iron, but this will assist in case I'm not able to get that 'perfect' seal.

I foresee some potential modification though when using on an ATP turbo. dunno.

[dturboman]

Originally Posted by NJSPEED3 Didn't dturboman make over 500whp with that turbo? @dturboman Sent from my XT894 using Tapatalk 2

I sure did... barely and on 30+psi, race fuel and ported hotside but it did it

Originally Posted by 86azms3 I think kmac is atp hotside right? He's at like 500whp, then there's that tranny kissing guy, joel. He made nearly 500. Dturboman also made 500whp realm on VD. Me personally I'm keeping it conservative. 22-23psi. I know when I was stock turbo I saw a 4-6g/s improvement from just a catback. People love to say a catback does nothing...but every little bit will help. I like Eric's idea...but just make a 3.5" exhaust downpipe back. Did you port the turbine housing at all while you were doing the flapper. I definitely ported mine and i'm sure it helps some (that hump at the wastegate seemed like a restriction)....and I'm sure it helped create creep issues I was having in the beginning.

made it on VD and a real DJ

dynosheet on 30+psi race fueland track vid on 26psi/93 octane

because Haters gonna hate