Dang, you're going to Iraq soon? It looks like I'll be joining ya soon too. The army is calling up more and more reserves each day. You'll come back... 6K will be set aside for my evo. No wife to tell me what to do, hehehhe....

 

Status is the main bearing i have been waiting for should be here before 10:30 today. "9:00 now" And i will throw the crank in and the bottom end together. Hoping to have the engine built by this afternoon and be going in the car by 3-4pm. First startup will be today. CROSS YOUR FINGERS!!!! This whole down time while i have been doing the build i have been reading non stop about the aem and i just now am starting to feel more comfrotable tuning it myself. But we will see i will only tune it for every day drivability and take it to someone for the peak HP. So i will get back at you tomorrow and let you know if im selling the car or not. LOL.. YA RIGHT!

Chris

 

Great news, hope everything will be ok now.

I’ll change the exhaust housing tomorrow and I’m chasing the tuner guy to book a new tuning session, I really hope I won’t have to wait too long for that. Haven’t been able to get a hold of him for a few days, heard a rumour that he were on vacation in Greece so that might be a reason.

 

What exhuast housing did u end up getting? the .82 or .106

 

I got the .82, according to Paul @ ATP there is no EVO bolt on 1.06 housing available. I was a bit concerned when I received the new housing as there were no markings on it as on the .63 and when I gave them a call Paul said that since there are only two versions available they only put markings on the smaller housing.

I might change back to the .63 if we manage to get the knocking issues solved and the .82 feels too laggy and slow spooling. Money is really the issue right now and I can't afford more than one more tuning session this year so I figured I'll change to the .82 as well as turn that cam shaft sensor cylinder at the same time.

 

Well i think you did the right think going with the .82. Unless you got it stroked then the 1.06 might come in handy but i know you and you want the fast spool..lol.. Man some people (Az3er!!) Anyway as far as the CAS sensor you did put the dowel pins on the cams pointing straight up. THen on the CAS sensor there are 2 tabs one that is small and one that is bigger. If you were to look at the CAS sensor the bigger tab should be pointing to the bottom right around a 45 degree angle. If thats all lined up you are good to go!!

But now i must ask you a question. What you think. Should i get a water injection kit or save the money for the tune?


Chris

 

That's exactly like the description and the picture in the work shop manual. BUT, you must zero the engine first as you could still have the pins pointing straight up but 180 degrees wrong as there is no other way of telling how the cam shaft is turned as far as I know?

I guess I would rather have the engine properly tuned without water injection than the other way around don’t you think?

So is your engine back together now or?

 

Hmm my understanding was that the dowel pins facing up was at TDC. And of course you would want to make sure the crank is at TDC also but if you havent taken off the timing belt you should be ok. Always a good idea to double check though.

The only reason i would like to get the WI is our 92 octane sucks!! And buying C16 (116 octane) is getting to be really expensive at like $5~$6 a gallon. So it could be like running race gas all the time when you are really running pump. Methanol is pretty cheap also i think cheaper then normal gas. But i dont know the origional kit i found was $700 but i found one yesterday for $399. So now im at a loss. But i think i should probably get the engine running agian before i buy anything else. LOL..

As far as the engine the damn main bearing still never came in yesterday even after i took the day off and they promised me it would be there before 10:30. What a waste of a damn. So hopefully it will be there today. EIther way this weekened for sure.

CHris

 

We changed to the .82 housing last night and everything went fine, one strange thing though, after changing to the larger a/r housing I had expected between 400-600rpms slower spool but in reality I can’t see any difference at all. When I got the new housing it didn’t have any markings on it like the .63 housing had so I called ATP and asked about that. They then said that they only have two housings available for the EVO and that the smaller one has a .63 marking and the larger one doesn’t have any markings, so if you have a housing without markings you know it’s the larger one.

Anybody on here that got a .82 turbo? Did you see any marking saying .82? On my .63 the marking was moulded into the housing on the inside of the flange towards the exhaust manifold.

I feel very insecure now of what I have put on my car. In general, if you had a .63 housing and a .82 housing at hand should the .82 be visually larger then? The only thing besides the lack of marking that I could see was different on the new housing was the exhaust outlet. Now you have to bare with me on the language because I don’t know the correct terms here but the outlet looks like a cone narrowing down to the exhaust impeller. On the old housing that cone is rather pointy and the hole where the impeller is in is pretty short. On the new housing this hole is “longer” and the cone less pointy so that the impeller never goes outside the hole like it did on the previous housing. I hope this made some sense?

I always thought that the a/r is a ratio inside the “snail” in the housing and had nothing to do with the exit hole? So what kind of difference would this different design on the exit do to the characteristics of a turbo in general?

 

ATP's business ethics are a bit suspect at times. I don't know about the cone that you're referring to, but I would guess that you're talking about the turbine housing outlet where the impeller exducer sits? This wouldn't really matter. Another thing you could be referring to is the turbine scroll area where it tapers at the end? This could make a difference, but if the outside of the .82 is physically identical to the outside of the .63, they're most likely the same. An .82 looks a bit different then the .63 or it should.

However, I don't think it's really going to help you w/ your surging problem. ATP's turbine housing is beyond on-center, a very bad design as far as efficiency purposes and is only provided for fitment purposes. You see, the manifold has to make a sharp 90deg turn at the exhaust manifold and then travel beyond a 360deg turbine scroll (the beginning of which is a rather sharp transition). There are too many bottlenecks there and can easily choke the turbine wheel/exhaust flow when getting up into the higher boost levels. A ball bearing turbo's characteristic is 'after spoolup' performance. They won't get you a tremendous amount down low but once they start spooling, let say, after 12psi, that's when they start really flowing which you've probably noticed. They tend to move large amounts of air in a very big hurry and you would need an efficient flowing system to realize their potential. I think a tangential turbine housing is a no-brainer...

 

Well question is did it fix the problem?

As far as your questions the outside diamiter of the housing normally is a little bigger but i dont think you would really visually see a difference unless you went up to the 1.06 housing. Now that does not mean that the housing is not bigger. Just becouse the outside is not visually bigger does not mean the inside of the housing is not bigger. Im sure you got the right one man dont worry Paul would take care of you. Also there are sized on both sides of the turbo. I think you got the 4" inlet which with my 35/40 it is a .70 A/R on the compressor and a .63 on the exhaust. Both of which are marked on the outlets of each side.

Now as far as the previous post. Actually the ATP exhaust housing is very well designed probably one of the best for the evo at the moment. One it uses a twin scroll design (kinda) and 2 it has the wastegate housing cast into it. To be able to control boost that is the best possible place for a wastegate to rest. As far as the 90 degree bend im not sure im following you there it actually is about a 45 degree bend if not less then it hits the fins on the turbo and exits at that point along with the full duration of the exhaust wheel. Also if you have seen the housing you would know that that inner diamiter of the housing is about twice the size of a normal T3/T4 housing. I really dont think that you can say that the housing have a poor design unless you have flow bench marks with it and a competitor.

Chris

 

No, it does not use a twin scroll design in the very least. The manifold is equal pulsed which is good but very restrictive in the 'collector' area. Trust me, I do CFD analysis all day. The wastegate housing is fine. As for the 90deg bend, the manifold has to go through a 90deg bend (which is fine) but then, it has to go through a beyond on-center turbine scroll which is not good. The inner diameter of the housing is twice the size of a normal T3/T4 housing? That would be foolish and would affectively change the A/R. You just can't 'hog' out the turbine scroll. Area of any given cross section/ratio at any given point in the scroll would give you the A/R. I can say that that the only reason why the stock evo manifold is the way it is, is because of the use of the reverse rotational 16G turbo w/ tangential turbine. ATP didn't have performance considerations when developing this, just fitment considerations. Its surging w/ a GT30R, I can imagine what it's going to do w/ a GT35...

 

Thanks for your input, and yes I was talking about the turbine housing outlet, and if you look straight into the impeller at least to me the housing going into the impeller could be described as a cone shape but that might just be the ATP design then?

I can easily see your point regarding the design of their housing as it must be some kind of compromise to get it to fit on a stock, or in my case stock like, manifold.

Back to the .63/.82 issue and I would guess I just maybe got a newer design of the .63 then

I’ll give ATP a call tonight (my time that is) and try to find out what I really got.

 

Well i has no surging at 30psi with my 35/40R and the .63 housing. I made over 500whp on stock internals. So obviosuly there wasnt a problem there. Now i just rebuilt the engine from the ground up and am planniong on 650-700whp at 40-45psi and im sure i wont have a problem there either but i will keep you posted.
As far as the inner diamiter of the collector yes it is bigger and i have pictures of both my old T3 and this turbo to prove it. There also is no 90 degree bend that you are talking about. Im not doubting your knowledge in CFD analysis but i am doubting your knowledge in the certain products we are talking about. And as far as the twin scroll is concerned the housing is broken up into 2 chambers off the manifold. THe cast on the housing forms this to say the least but yes is collects all into one. Which is no big deal as long as the manifold itself is a twin scoll design which is the important part in the first place. I will post pics of the difference in a little.

Chris

 

Hi Chris,

No it doesn't seam to make any difference at all to the surge, that together with the fact that spool up didn’t change at all either, I’m still seeing full boost around 3,5k, makes me think that perhaps I got just another .63 I’ve really looked outside and inside and found no marking at all on the new housing. That’s why I called Paul just after receiving it and he then told me that there is no a/r marking on the .82 housing and the reason were that they only have .63 and .82 EVO housings and no marking then tells you that it’s .82, sounds kind of strange to me when thinking more about it though?

If I lower boost between 3,5k-4,5k the surge is drastically reduced though, this of course gives a possibility to map “around” the problem so to speak as I can control boost both on rpm and gear with the Motec but I’m still puzzled that not more people are getting this problem?