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An m90 build to decimate all


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GTPpower

GTPpower

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Video from the Dyno day on Sunday. Power was pretty weak, but thanks to all the local friends that were there, I had lots of eyes to help me watch it. We found out the bypass is not closing. I'm not sure how it's even making boost, but at least now I know the problem why it's not making the power it should. So, now I'm going to weld that shut, install a bov, and I'm about 97% sure that I'm gonna to fix the transmission myself.

 

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1.8 pulley with 5% overdrive, what's the math? <--- That's what he's saying. Cause you said you're running a 2.7 with the 5% overdrive. I assume he said that because the blower whine is pretty wild and it sounds like it's being super overdriven.
 

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I would assume boost, cause who really cares how fast the blower is spinning, the 3800 world doesn't ask anything but what pulley size and how much boost. Innit?
 
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GTPpower

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Oh, in that case, I have no idea. The drive costs would be tremendous, so little chance of no belt slip. I doubt the math would be accurate.
 

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I would imagine the drive losses would be insane if there was a way to spin it that fast. I also don't think he was seriously asking. I think the sound of your setup is so unique it'll have people thinking you're running a super small pulley. They certainly won't take the time to read anything you put in the description, TCG and the world, does not read.
 

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I would do it as 2.70/1.05 which is around 2.58". I may be off on this but I think the ratio should be simple being based on linear distances. I would go up on driven pulley size vs down on blower snout pulley size if plausible just due to the belt area up top being small.

Based on a 6.94 stock crank pulley diameter*1.05 divided by 2.7 I get a ratio of ~2.7:1. How odd it worked out evenly like that. You'd be looking at what 16.2K if you were spinning the engine up to 6 grand. Off the sheet if I remember right.
 
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I would imagine the drive losses would be insane if there was a way to spin it that fast. I also don't think he was seriously asking. I think the sound of your setup is so unique it'll have people thinking you're running a super small pulley. They certainly won't take the time to read anything you put in the description, TCG and the world, does not read.
Ah haha. Ok that makes sense.
 
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GTPpower

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I would do it as 2.70/1.05 which is around 2.58". I may be off on this but I think the ratio should be simple being based on linear distances. I would go up on driven pulley size vs down on blower snout pulley size if plausible just due to the belt area up top being small.

Based on a 6.94 stock crank pulley diameter*1.05 divided by 2.7 I get a ratio of ~2.7:1. How odd it worked out evenly like that. You'd be looking at what 16.2K if you were spinning the engine up to 6 grand. Off the sheet if I remember right.
Yeah, it's easy to figure blower rpm.

I would like to go bigger on the crank, but the ati 10% balancer is like $600.

I found someone selling one with a 28% od pulley, which is around 10". So I could run a big upper and not worry much about belt slip, but I'm not sure that would even clear my subframe.
 
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How much hp
It made 290. About the only thing encouraging about that is, it's an 11 second car with that power and a good trans. So once I fix my boost leak and dial the tune in, it should run mid 10's at my terrible density altitude.
 

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