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Discussion Starter #21
Brotato, I suspect you're gonna like that G42. I thought about getting one just for shits and giggles to see what I could really push out of my 1j, and how high it would rev and still make power, but... for one, it's pretty much impossible to put that sort of power down on our filthy desert roads, and two, I suspect it'd make enough torque to break the transmission, and possibly the diff. Last thing I want is more things to break haha.

But seriously, I have one of their G25's, and the way that little tiny thing pulls, I can only imagine the G42...

Yup, I have 28" Hoosier DRs, so she'll hook on our Texas tolloways(err mexico). I'm getting DS loops put in. I fully expect something in the drive-train to give away. I'm hoping for 1050-1100whp, sub 30psi, to 8200rpm.
 

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Discussion Starter #22
Yeesh. That's way more than I've experienced. Even my race car doesn't see that much oil in the can. I usually don't need to drain the can at the end of a track day. It's usually just out of good habit. And trust me there's a lot of full throttle there. I find the blowby excessive but if that's how they built it, then that sucks.

Have you done a leak down? I'd be interested to see the numbers on the crank. 5 bucks you put compressed air on a cylinder and it sounds like a trumpet lol
We will, as we put the new turbo on. But I suspect it's fine. She made 960whp on the tiny 6870 a couple weeks ago.

Wow that's a pretty big failure. I'd be pissed with that usage and outcome. I always thought the Precision failures were more myth than reality.
The shop that built my motor stopped using them years ago, they had too many failures. They like Garrett, Borg, & Xona
 

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Don't overspin the Garrett and you'll be fine. Read the comp chart and genuinely plot the approximate RPMs of the turbski and you should be fine. This is advice for Garrett owners who love to push their turbos waaayyy past the airflow they were designed for and then wonder why they fail fairly early.
 

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Discussion Starter #24
So we've concluded that my catch can breathers are too small, thus allowing pressure to build up.

We're going to attempt running an intermediary collection/drain tank in the block vent line(where the oil level sensor used to be), before the catch can.

We've seen others do this with good success.

We also think this new G42-1450 turbo, running 10psi less than the 6870, will help significantly as well.

I'll report on the results in the coming weeks.
 

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Crazy... I have a pretty 'loose' motor and after 500 street miles and half a dozen drag passes in the 157-160MPH range my catch can has maybe 6oz of mostly water.
 

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There's really something special about a JZ once they pass 8k rpm that I just love. Suppose that goes for most any engine, really, I'm not too picky, but some engines just pick up a unique anger at that sort of speed.

Would love to see where your turbo spools up at, give your lack of altitude. The G25-660 0.92 is pretty much all in by 3k, in first gear, at 6500' altitude, so it's a great setup for what I do, with autocross. It made the car FUN again. I reckon that we're approaching a nice "have your cake and eat it too" where we can have turbos that make power like they're a size bigger, yet spool like they're a size smaller, than what we were running ten years ago.
 

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Discussion Starter #28
There's really something special about a JZ once they pass 8k rpm that I just love. Suppose that goes for most any engine, really, I'm not too picky, but some engines just pick up a unique anger at that sort of speed.

Would love to see where your turbo spools up at, give your lack of altitude. The G25-660 0.92 is pretty much all in by 3k, in first gear, at 6500' altitude, so it's a great setup for what I do, with autocross. It made the car FUN again. I reckon that we're approaching a nice "have your cake and eat it too" where we can have turbos that make power like they're a size bigger, yet spool like they're a size smaller, than what we were running ten years ago.
Exactly, I should've also mentioned that I'm revving to 8300 w/40psi. I'll post the dyno of the G42-1450 in the coming weeks. I'm really not concerned about spool, this is a mexico/halfmile car after all. Response between shifts is a concern though.
 

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With those sorts of RPM's and a G-series, don't worry about response between shifts. If I'm anywhere above say, 3500 rpm on my setup (and considering my environment), mine is pretty much instantly full boost of ~20 psi. That's not a lot of rpm...

You're gonna be dropping down to 6k, worst case scenario (I'm making assumptions, considering I have no idea of your gearing), which is plenty of rpm after a shift. I'd be willing to bet it is back on serious boost in under a half second.

Then again, I've never driven a car with a turbo that big, so perhaps I'm mistaken. If it becomes a problem, HGT is happy to take your money haha.
 
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