Anybody try converting their RD-80 to an RD-90?

DirtyWood

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I've been running the RD-80 for a few weeks and like it a lot, but of course there is the temptation to convert it to an RD-90 using the included instructions. Anybody try this? Results? I definitely have some ceiling left in terms of EGTs but I do take to heart Justin's warning about running the RD-90 without studs.
 

Nero

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You only need to worry about studs if you start pushing over 12psi boost. You can turn it up, and trial and error it to find the sweet spot that works for you.
Little tip, use a paint pen on the balancer and the oil pan once you have the fuel adjust screw visible for easier future adjustment
 

Clb

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Wellllll
Not to be a d++k but justin told me to set 15 # as the waste gate setting.
@IDIoit
might have some input here...
 

Nero

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Nah you good, I've heard several specs for max psi for non studded blocks. Some even as low as 8psi.
I would be hesitant to go up to 15 on a stock head gasket, would consider if it was a composite gasket.
 

DirtyWood

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Nah you good, I've heard several specs for max psi for non studded blocks. Some even as low as 8psi.
I would be hesitant to go up to 15 on a stock head gasket, would consider if it was a composite gasket.
Composite head gasket? I used Fel-Pro Permatorque blue gaskets.
 
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