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What kind of punishment can you put the stock drivetrain through before upgrading? I have a R33 with an auto. My HP goal is 450-500. Motor is built for it and just recently installed it back into the car. Haven't started it yet cause waiting on a few more parts to come in the mail. I've been so wrapped up with other stuff that I just realized that I haven't touch the drivetrain. Wouldn't mind going to a manual but running out of time for this to debut at a show and sourcing parts here in the US is difficult. (car must be driven 600 miles to attend) Can the auto transmission, torque convertor, drive shaft, rear diff, etc handle this power? I've attached the vin plate for better insight. post-116132-13786745979762_thumb.jpg

The RB25DET gearbox can easily handle the power (really, the torque) levels you're talking about. But of course it is better to do it on one that is either new or freshened than to do it on one with worn selectors, synchros and all that jazz. The main components are big and heavy though, so they can certainly carry some mechanical load.

The diff is big and stron, the tailshaft and driveshafts are all strong. But the same things applies. Sloppy old CVs will always give before good condition ones will.

Word is that the stock bottom end of the RB blocks handle almost 1000hp. That's what I guess I'm asking. What kind of power the stock RB gearbox auto and manual would hold along with the rest of the drivetrain.... Has people snapped axles or C/V's?

The RB25DET gearbox can easily handle the power (really, the torque) levels you're talking about. But of course it is better to do it on one that is either new or freshened than to do it on one with worn selectors, synchros and all that jazz. The main components are big and heavy though, so they can certainly carry some mechanical load.

The diff is big and stron, the tailshaft and driveshafts are all strong. But the same things applies. Sloppy old CVs will always give before good condition ones will.

Thanks! I was typing and didn't see this response yet.

The RB25DET gearbox can easily handle the power (really, the torque) levels you're talking about. But of course it is better to do it on one that is either new or freshened than to do it on one with worn selectors, synchros and all that jazz. The main components are big and heavy though, so they can certainly carry some mechanical load.

The diff is big and stron, the tailshaft and driveshafts are all strong. But the same things applies. Sloppy old CVs will always give before good condition ones will.

Do they make new gearboxes? I was thinking on ordering a used one if I come back with the car and doing a refresh on it. I'd love to do a ratchet trans but putting that kind of money in a transmission is hard to ask for it back.

New RB25 boxes are available for about 3 grand here in Oz. Worst case you could order one from here, but I'm sure that Jap sourced or possibly US sourced alternatives should exist.

1000HP should not be attempted on RB blocks without a partial grout fill. They will do it, but they will end up splitting. Grout filling is cheap insurance if you're planning to go mental on power levels.

If you are planning to go that far, then you have a lot of reading to catch up on.

New RB25 boxes are available for about 3 grand here in Oz. Worst case you could order one from here, but I'm sure that Jap sourced or possibly US sourced alternatives should exist.

1000HP should not be attempted on RB blocks without a partial grout fill. They will do it, but they will end up splitting. Grout filling is cheap insurance if you're planning to go mental on power levels.

If you are planning to go that far, then you have a lot of reading to catch up on.

I don't recognize that term grout fill?

Thanks! I was typing and didn't see this response yet.

People snap axles at the drags with 700hp or less but Rips put over 1000hp through a stock front and rear end (but with a monster powerglide/transfer box)

Is that like installing thicker cylinder sleeves? If so, I understand that.

No - imagine taking out the frost plugs and pouring concrete in to the block until its half full.

Here ya go - apparently Yanks call it Hard Blok

http://www.jegs.com/webapp/wcs/stores/servlet/KeywordSearchCmd?storeId=10001&catalogId=10002&langId=-1&Ntk=all&Jnar=0&Ne=1%2B2%2B3%2B13%2B1147708&searchTerm=hardblok

Do they make new gearboxes? I was thinking on ordering a used one if I come back with the car and doing a refresh on it. I'd love to do a ratchet trans but putting that kind of money in a transmission is hard to ask for it back.

There's quite a few options - e.g. OS Giken from Japan PPG dogbox from Aus Autosalon Yokohama from Japan and HKS dog box H pattern or sequential like this: http://www.trademe.co.nz/motors/car-parts-accessories/nissan/gearboxes/auction-635181453.htm

and more...

There's quite a few options - e.g. OS Giken from Japan PPG dogbox from Aus Autosalon Yokohama from Japan and HKS dog box H pattern or sequential like this: http://www.trademe.co.nz/motors/car-parts-accessories/nissan/gearboxes/auction-635181453.htm

and more...

Yeah, look at the price tag. $15k isn't exactly cost efficient. Wouldn't mind spending $4k on a trans but not $15k. I couldn't ask $15k or more on an upgrade like that. There's a reasonable percentage you can ask for when selling your car when heavily modded. But I must admit, that HKS kit would be a dream to have.

No - imagine taking out the frost plugs and pouring concrete in to the block until its half full.

Here ya go - apparently Yanks call it Hard Blok

http://www.jegs.com/webapp/wcs/stores/servlet/KeywordSearchCmd?storeId=10001&catalogId=10002&langId=-1&Ntk=all&Jnar=0&Ne=1%2B2%2B3%2B13%2B1147708&searchTerm=hardblok

Yes. I know that term. I steer far from that. Heat dissipation and heat soak become issues

Yes. I know that term. I steer far from that. Heat dissipation and heat soak become issues

No they don't. You don't have to fill the whole water gallery. 1/4 fill is sufficient to re-inforce the weak part of the block.

This is one of the reasons I said you have a lot of reading to catch up on.

No they don't. You don't have to fill the whole water gallery. 1/4 fill is sufficient to re-inforce the weak part of the block.

This is one of the reasons I said you have a lot of reading to catch up on.

I'm not going that route. No reason to have that much power in a Skyline. 500 is plenty. If i wanted more, I'd do a LS swap. Thanks for the info though. It's helpful. Just wondering about the drivetrain and its reliability.

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