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I've got a RB30E short motor that has done around 280,000km's.

I am going to slowly rebuild it but I am going to try and do as much as I can my self to save some $$ as I am at Uni.

Here's what I have in mind:

RB25DE Head ~$800-$1000

Custom 9:1 or 9.5:1 Forged Pistons ~$1400

Possibly O-Ring the block.?!?!?!

RB Piston oil squirters.

GCG Stage 2 500HP Change over. ~$2400

R33 PowerFC.

I am hoping that I can get away with using the standard Crank and rods.

Will the Standard Crank and rods hold 250 maybe 270rwkw reliably all day every day reving to approx 6500rpm max 7000rpm?

Also to make sure the rods/crank are in good nick what or how should I check or get them checked?

Is there anything else I have to check or make sure isn't wrong with the block before proceeding?

Does the R33 Wiring loom interface with the R32's running gear?

Thanx ppls.

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Hi Joel,

Glad you've got a block and are ready to start.

The crank should be fine, but the rods may need replacing depending on boost levels.

I'd suggest that you get everything crack tested or X-rayed, that way you will know if anything is shot before you start.

See'ya:burnout:

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I was looking at running a max of 18psi.

A Couple of Questions

Any probs with the Rods at that Boost level?

Piston Oversize. What is the maximum safe oversize one would want to go?

How would the 9.5:1 CR go with that sort of boost?

I've got a good Bar and Plate FMIC so the air charge temp is not a problem.

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This is what an o-ringed head looks like. Sorry I couldn't find a o-ringed block picture!(EJ25 subaru)

Not much here, except for the two thin rings added to the head surface. You should be able to find a highly skilled machinist to do a similar job.

You need to o-ring a block if you want to run high boost levels!

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joel my thoughs on this are simple

use stock gtr pistons stock rods and crak they should be fine if tested etc teh pistons are aroudn 8.5 to1 compressiondont go high compressioon its not worth it you will have the capcity to spool a large turbo and 250-280 rwkw should be doable and you wont be running that kind of power level all day any way

with thehigh compression you might run in to fuel issues if you go country.

also try and source a head off an rb25 de from an r32 the loom and ecu go in quite easily and it uses top feed injectors jsut liek the one on my site btw the guy is in adeaide so it might pay to contact him.

good luck I would be thinkingabout an rb25 gearbox though the torque will be a bit to much for and rb 20 bx

M

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Joel,

Meggala is right with his suggestions, the GTR internals will be much stronger, and they are cheaper than forged items. I would say that it would still be worth shot piening them for extra strength. An RB25 head is also a pretty good idea for moderate horsepower, if your building a race engine then buy the RB26.

See'ya:burnout:

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Thanx.. GTR pistons are the way to go then.

save a few $$.

I was looking at the VCT head as it will provide a little more down low and a little more up top also.

Hence why the RB25DET PowerFC.

Apparently there isn't much between the RB30DET without VCT and the RB25DET with VCT when it comes to down low torque.

Really depends how much of a hassle the VCT is to adapt.

RB25DET box is a definate. My ol' RB20DET box is becoming quite whiney lately. Especially in first and second.

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Joel with a 3l block why not get a decent turbo, the highflow would not be big enough for that size motor and would restrict top end a lot. For 2300 you can get a GT30 roller bearing turbo that wouldnt be very laggy on that motor, all you would need is an external gate mounted to the stock manifold and you could make your 250+ with low boost easily. Your going to do it all properly so you may as well make a few oil and water lines as well.

Should be a beast when its done.

Try and plan out as much as you can thought jont just let it flow along, or you will be like my mate building a race car and with not a lot done after 2 years.

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I want it to be as responsive as possible even if top end maxes out at around 250rwkw which is plenty for the street in a R32.

I am aiming for lots of power in the mid range.

Plus the money I could save without having to change manifolds etc.

I'll have to speak to a few people regarding the turbo side of things and see what they come up with.

So does the static CR make a difference to power once on boost or does it simply make the turbo spool quick and provide more power down low?

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Id look into getting something different, the stock exhuast housing is pretty small and i would think would be at its limit at 250rwkw. there is going to be a lot more exhaust gasses with the bigger motor so a big housing will be required. Look at the new xr6, these things have pretty big turbos (GT40 or something) and with there 4l spin them up easily so they have very good low down torque and power with 7psi or something.

Id say my turbo would be just about perfect on a 3l and at 20psi would make 250rwkw easily.

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