scorke

iTrader: (18)

Ah, it wasnt clear when you said "BTW - the Megan header is $199 bucks on Ebay. Not a large expense that takes the ATP kit into the territory of a Vishnu or Buschur." I assumed you were talking about performance, silly me.

I thought DB did a test comparing multiple headers vs the stock ported/coated manifold and found that the only manifold that actually made more power was full-race's and it was minimal. So what we do know is the megan header doesn't help much if at all, and is a flow restriction compaired to the stock manifold.

Scorke

EvoIXMR

iTrader: (66)

interesting thread. Now, this may be a dumb question, but I will ask - I notice that the turbine housing pictured was not divided (tagential?) But, the stock and megan manifold both are? Will removing the divider for this turbine housing help?

scorke

iTrader: (18)

No, it wont help, it will hurt spool time for sure, which is most likely the reason for the ATP's lacking tq numbers. What would be good is if the ATP housing was actually twin scroll like the stock turbo, since they make a divided t3 manifold I don't see making a twin scroll housing that mates up to the stock turbo a stretch at all....

The purpose of the divider is to make the timing/flow of the exhaust gas hitting the turbine as turbulence free as possible, having it collect like that in the ATP housing is nothing but bad news.

Btw tangential is in reference to the angle of how the flange (T3,T4,Stock...) is oriented in reference to the turbine wheel. With a tangential housing the exhaust gas hits right on the tip of the turbine wheel( think-tangent line touches a circle in exactly one spot). A tangential housing design is supposed to be optimal however some turbo companies sell housings with the exhaust gas pointed much more dead on to the turbine and not at as sharp/shallo of an angle depending on how you look at it.

Scorke

SmokinJoe

iTrader: (17)

Please refrain from making judgemental comments in this thread and bashing ATP. Millions - maybe even billions of turbos have been produced without a divided scroll with excellent performance. The divided scroll is an improvement and does not categorize all other designs as "bad news".

That would be like saying the EVO 8 is crap compared to the improved EVO 9. Not entirely accurate, eh?

I'm putting in my time, labor and $$$ to benefit this forum. I'm not here to support or bash ATP. I would expect the same respect from everyone reading and replying here.

Thanks

scorke

iTrader: (18)

First off, my comments are not judgemental at all, they are based on facts and results that you and other members have reported from owning ATP kits.

Secondly, yes gagillions of turbos have been produced without a divided/twin scroll housing, but none of these non twin scroll housings have been proved or shown effective when mated to a twin scroll manifold, which is exactly what you plan on doing. So yes the design/setup you are going to run is bad news.

I'm not here to bash ATP either, I put my own time and money and resources into piecing together a car that performs. It seems to me like you don't seem to believe everything that has been posted on these forums regarding everybody elses results, and you believe that with the addition of a cheaply designed manifold will solve all your problems, while I am trying to tell you it won't, and I am trying to help you get some good results.

Scorke

SmokinJoe

iTrader: (17)

Scorke -

For the last 16years - and maybe longer - Nissan has been producing a divided manifold mated to a undivided turbo. I know this because I own an SR20DET NX2000. I also used to own a JDM GTiR Pulsar.

The division of the exh banks without the divided scroll is not bad news. Please get your facts straight - IT IS AN IMPROVEMENT.

But it seems like you already know the outcome of this test - so why the heck am I even doing it? Let's all put our faith in Scorke's word.

althemean

iTrader: (5)

Does the ehaust flow have to make a turn in the ATP housing before it hits the wheel? Almost a 90degree turn? If so....this is the disadvantage to this turbo. I am under the assumption that this housing was designed this way to overcome the reverse rotation of the stock setup. And in doing so, the ATP housing loses exhaust gas velocity...thus making this turbo less efficient than its T3 flanged counterparts?

Or am I misinformed?

scorke

iTrader: (18)

Using a divided manifold with a non divided turbo housing makes zero sense, if you can show me something that proves otherwise I would be greatly interested. I bet any undivided manifold made for the SR20 provides decent gains pending it isnt designed by a 4th grader.


Alt, you got it down pat.

Scorke

SmokinJoe

iTrader: (17)

Go find Rob Cadle at Garrett - maybe he can explain it to you. For Nissan to use divided manifolds with open turbine housings for 2 decades or more is proof enough that it works. Again - it may be not THE BEST. But it has and will continue to work just fine.

The ATP does not make a 90' bend. The problem I think resides in where the WG is located. Which is prior to the scroll - in the path of the exh flow. I dont know for sure - but I am going to test this theory.

Scorke's dyno showed a major reduction in torque after peak. Scorke lost about 50% of his torque - from 480 down to 260wtq. And he has a 2.3 and a NON ATP Kit. So - if he does have a divided scroll - maybe it isnt that big of a factor, since he continued to loose so much power.

scorke

iTrader: (18)

Why are you giving me the contact information for somebody at Garrett? If you know he can answer my question, it means you know what the answer is, so why dont you share why this is such a good idea?

Rather than citing the example of the SR20 as being a good powerplant/motor, I will go ahead and reference you to the 4G63, which uses a twin scroll manifold with a twin scroll turbo, and makes an assload more power and tq.

I don't have a twin scroll turbo or manifold, twin scroll helps out in the spool department and would have an impact on top end power, TQ drops off so badly in my car because I am at the limits of the 3076 for my particular setup, thats why on my racegas tune the boost tapers to 26 psi at the end of the pull as opposed to the 30 I am getting at 4800rpm. Here is the proof of my horrible looking, tq lacking dynosheet you speak of for all you other guys that are interested.


Scorke's dynosheets also poo on any sheet of any ATP kitted car the world has ever seen. My car on pump made 380/360 at 20 psi with 500 miles on the motor. It made 490/480 on race gas. Here is a sample of ATP kit numbers as a comparo
- https://www.evolutionm.net/forums/sh...ht=atp+results
- https://www.evolutionm.net/forums/sh...ht=atp+results (this guy makes the same tq that I make at 20 psi on pump at 26 psi with c16)
- https://www.evolutionm.net/forums/sh...ht=atp+results (364/320 at 22psi)
- https://www.evolutionm.net/forums/sh...ht=atp+results
(430 360 25psi 100)
- https://www.evolutionm.net/forums/sh...ht=atp+results (408 349 26 psi 110)

I know none of these comparisons are apples to apples, but the bulk of them are on dynojet's(what I dynoed on) the one Mustang Dyno that was used for one of these links supposedly reads like a DJ (from warrtalon who spends far too much time on here, so its probably the truth) and all of they are FAR below the results I make.

Yes your atp kits tq doesn't drop off as badly as mine does, sadly its because they have never climbed signifigantly higher than what I make on pump.

Scorke

SmokinJoe

iTrader: (17)

I knew you'd fall for it.

scorke

iTrader: (18)

How much less tq did your atp kit make on pump gas/race gas? If it's easier for you just give it to me in hundreds.

Scorke

240Z TwinTurbo

iTrader: (25)

SmokinJoe,
I for one am glad to see you try and provide and unbiased review of the ATP setup in comparison to stock. I look forward to your results.

althemean

iTrader: (5)

https://www.evolutionm.net/forums/sh...d.php?t=163624

This guy is only making 20 psi by 5500rpm. I dont think it is a question of can they make power so much as it is WHEN it makes its power. Repeated results posted by members all show the ATP kit to have a signifigantly later spool compared to a true Garrett hotside. I know for a fact that the ATP kit has a large bend in the hotside. You can see it and would have to be blind not to.

The above referenced thread is the most unbiased one I have read on the ATP kits and even he conceded that spool sucks and he is ready to get rid of the turbo. His whole premise was the same...install it and find out the truth. Well...the truth is....spool sucks on the ATP kits. No argument. Its a closed case.

The match porting trying eliviate this interesting but its not gonna do it. That hotside is the limitation. For someone looking for a cheap turbo to bolt on and say my car makes x amount of power...maybe this is the turbo. For someone caring about tracking the car and transient throttle response....this turbo sucks *****. Once again, the above mentioned post has logs that show an atp 3037s making 10.5psi @ 5k RPM! Thats proof. It was logged. It was posted in a very open and frank manner.

Arguing that this turbo is equal to a AMS or Buschur kit is stupid. Its not. Never will be.

Keep in mind I run a stock turbo and have no vested interest in defending or promoting any of these products. I am just interested in straight facts...some of which seems to be getting distorted as peoples feeling are creeping into the discussion rather than logical thought process.

By all means...please continue your test and post the results. I would like to see another review. The more info the better.

SmokinJoe

iTrader: (17)

Who said that? It certainly wasnt me.

Again - let me restate the test. I have a solid baseline of my car - right now. I am going to install the ATP and overlay the curve to my stock curve. We then can FINALLY compare spool, peak torque, overall torque (curve), peak hp and overall hp (curve) to the stock turbo.

This test is not about AMS or Vishnu. Get off my back and let me do this.