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Discussion Starter #21
Alright guys, well I tried to pressure test but my pressure tester blew apart. I did notice that air was coming out of the 2nd nipple on the greddy BOV is this normal? I also had pressure in my crank case. I took the hose off the PCV valve and put a bolt in it but I had pressure coming through. Is this normal? I also gutted my rear pre cat but that made no difference. I'm gonna order the boost test tool from 3sx and try again. I'm consistently dropping to 12.9 psi by redline.
 

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Discussion Starter #22
Well guys, I adjusted preload that didn't fix it either.
 

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When pressure testing, everyone seems to forget the other vent hose that goes from the rear valve cover to the MAF bubble. You have to block that one too or you'll pressurize the crank case.
I don't know anything about Greddy BOVs, but it sounds like yours is bad if it leaking.
 

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When pressure testing, everyone seems to forget the other vent hose that goes from the rear valve cover to the MAF bubble. You have to block that one too or you'll pressurize the crank case.
I don't know anything about Greddy BOVs, but it sounds like yours is bad if it leaking.
No, the greddy bov's are just like that. Also if you have a good EBC such as a greddy Profec-b SPEC II, it has GAIN settings made just for helping hold boost till redline, not sure if AEM does this or not.
 

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Discussion Starter #26
Ok guys, I finally got my transmission nightmare over with so I'm back on this issue. I still can't hold boost till redline. I put stiffer actuator springs and same problem. I pressurized the system to 15psi and no leaks. I have no exhaust manifold crack along the front turbo either. My question is this. When you guys measure boost till redline does the gear make a difference. I know first goes by too fast so I've been measuring it in 2nd where it always drops off to 12.9 at redline. Am I supposed to be measuring it in 3rd gear pulls?
 

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Discussion Starter #28
You'll get a much better idea what is going on, and get full load in third... Only problem being, at redline in third of a 5 speed you're north of 120 mph...
haha..yeah, I'm afraid of cops over here. Seems like they've been tenting out lately. What would it mean if it holds 15 psi to redline in 3rd but can't in 2nd?
 

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If it's making good power that may be all it's got at that load, airflow, and timing. They aren't huge turbos. What is the A/F ratio doing in that area? Are you starting to max out the injectors and yank timing?
 

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Discussion Starter #30
A/F ratio is about 11.3. I do feel that it slightly loses power as the RPM goes above 5k in 2nd gear though but it pulls hard. I have an emanage blue and I don't know have a logger so I don't know what the injectors are maxing at (450cc). I just know that if I set the boost at 13psi it will be consistent to redline. Anything more than that even if its 13.5 it will hit that value but drop to 13 at redline. I'm just using stock timing and injector pulse. I only adjusted the airflow adjustment map.
 

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I have never had the chance to upgrade to a 13g setup but I always heard years ago that it would hold 15 to redline. and that was with a stock motor and injectors and back then almost always a manual boost controller. id be quite interested if one of the other old heads has an answer to this. I can only imagine it mite be something simple that doesn't make sense yet. best of luck with the repair.
 
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Are you 100% sure they are 13Gs? Pictures of the compressors? I had one 13G and a 9b way back years ago and it seemed to hold 17PSI to at least near redline, but I didn't log boost back then.
 

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Discussion Starter #33
Are you 100% sure they are 13Gs? Pictures of the compressors? I had one 13G and a 9b way back years ago and it seemed to hold 17PSI to at least near redline, but I didn't log boost back then.
Well after hitting 120 in 3rd gear they would still drop off. The intake side impellers are definitely 13g by looking at them. Also, 9bs wouldn't be able to hold 13 at redline. I don't know if a seal in the turbo can be bad but the turbos are really the only thing left at this point unless I have a crack at the waste gate housing which I doubt. When I had my actuators too tight it would boost creep up to 14 with the boost set to off on the truboost for what that's worth. I'm almost ready to break down and buy some 15g's I'd just hate to have the same problem.
 

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Discussion Starter #34
Well I may have found the issue. I seafoamed the intake this time to check the exhaust again and I had a leak coming from either the rear turbo where it mounts to the precat, the precat or the turbo housing itself. It's coming from underneath. It almost looks like it's coming from the bolt.
 

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There are several sizes of 13G compressor wheels, and one of them is very small.

The Euro 13G's are the small ones, they measure out to be similar to a 11B Compressor wheel, and that size of 13G can also be found on a 91-94 Automatic Eclipse GSX. I'll put money on you probably have Euro 13Gs.
 

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Discussion Starter #36
There are several sizes of 13G compressor wheels, and one of them is very small.

The Euro 13G's are the small ones, they measure out to be similar to a 11B Compressor wheel, and that size of 13G can also be found on a 91-94 Automatic Eclipse GSX. I'll put money on you probably have Euro 13Gs.
Well I know they are euro 13g as the part number on the turbos matches that. Aren't all bolt on 13g's the euro versions? Regardless people are holding 17 psi to redline on those. Only way to truly know if it's my turbo I guess is to put 15g's and see if the issue goes away.
 

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I think the 13G's people are running 17 PSI at redline are Subaru/Volvo, or Ebay turbos....

'Euro Spec' 3S 13G: Exducer 51mm, Inducer 40mm

DSM 13G: Exducer 51mm, Inducer 40mm

Volvo 13G: Exducer 56mm, 41mm

15g: Exducer 56mm, 43.5mm

the Volvo 13G also had a TD04HL Turbine which is MUCH bigger then the TD04 turbine

The subaru 13G uses a TD04L Turbine which is still bigger then the TD04 Turbine. That's where alot of power and boost is lost. It's a major choke point. Supposedly if you put a TD04HL-9B Together, it would hold boost to redline @ 15+ PSI..
 

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There are several sizes of 13G compressor wheels, and one of them is very small.

The Euro 13G's are the small ones, they measure out to be similar to a 11B Compressor wheel, and that size of 13G can also be found on a 91-94 Automatic Eclipse GSX. I'll put money on you probably have Euro 13Gs.
The factory installed 3S 13G, and the DSM auto 13G are the same CRHA. They are a TD04 turbine and the small 13G compressor. The 13G MHI replacement turbos generally had TH04L turbines, and the small 13G compressor. (that was the turbo of choice to use as a core for upgrades before Mitsu jacked the price to the moon) The large 13G Volvo is almost as big as a 15G, and usually used a TD04L turbine. (that's the compressor you usually get from any aftermarket source selling a 13G wheel)

So yes, I agree, it's possible for very different numbers to be produced by a turbo labeled a 13G, depending on what you actually have...
 

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Discussion Starter #39
Well I have another update. I dropped my exhaust from the downpipe back and I held more boost. I saw 14 at redline. I have gutted precats and a downpipe with no cat. I'm going to try again tomorrow and disconnect the exhaust from the downpipe to muffler and see what it does. Maybe my problem is the stock muffler?
 

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Stock catback is only a 15 hp restriction at 600hp, probably not it.

Also you should be able to hit full boost in 2nd gear easy. I hit 95% of my setpoint in 1st, 3rd is absurd to be checking on the street.
 
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