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This is probably the turbo I should have gotten. 5858 is too oversize for my goals. Anyway, looks like it's making nice power.

I don't know how to read those dyno charts. When does it start to spool.
 

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This is probably the turbo I should have gotten. Anyway, looks like it's making nice power.

I don't know how to read those dyno charts. When does it start to spool. My 5858 doesn't start until about 4k rpm.
One way to compare, which we commonly do on the 3sgte engine, is to look at the RPM at which the torque curve hits 200 rwtq. So just follow the 200 rwtq line across until it hits the actual torque curve, and then look down to see what RPM that occurs at. Sorry if that is way too much detail.
 

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OP,
I take it that you were running 93 octane on this?

For anyone else knowledgeable, and let's say OP was running 91 octane, running a 93 octane should allow for just a bit more boost at the same AFR, correct? I have the same exact setup but just a different exhaust manifold, and we have 93 octane almost everywhere here in VA. I am currently on 15psi and didn't wanna turn it up any further without having it on the dyno, while being able to read AFR. But by the looks of it, I'm even safe at 16psi.
 

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OP sold his MR2 last year and the buyer converted it back to "stock" Gen4. But I bought the turbo/exhaust and had it installed on my Gen4 so I essentially have his setup in my car.

I've been running 17 psi on 93 gas. I have a wideband in my car and the stock ECU seems to keep the AFR's pretty steady in the mid-11's at full boost all the way to redline. I've put probably about 5k miles on it so far.
 

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OP,
I take it that you were running 93 octane on this?

For anyone else knowledgeable, and let's say OP was running 91 octane, running a 93 octane should allow for just a bit more boost at the same AFR, correct? I have the same exact setup but just a different exhaust manifold, and we have 93 octane almost everywhere here in VA. I am currently on 15psi and didn't wanna turn it up any further without having it on the dyno, while being able to read AFR. But by the looks of it, I'm even safe at 16psi.
The octane shouldn't change the AFR. The higher the octane the cleaner the burn, which equals less knock, and ability to run more boost. If you're on 93, you should be fine all the way to boost cut (18psi IIRC) without your AFR getting too lean.

Say you're running 15psi with an AFR of 11.0. If you go up a couple of PSI to 17, your AFR would probably go to 11.5 or so because you've introduced more air into the engine while not adding anymore fuel.
 
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