Cjmartz2k

LOL, internet mechanic, eh? I've owned my R32 for about 4 years now (not that that proves anything) and have had it up above 400rwhp for as long as you've "been modifying your r33", so take that for what it's worth in the reliability debate. I don't feel the need to go into my friends and them "OWNING" a performance shop, me driving for them when the street tune (3 RB25's over 400rwhp in the past couple months) , helping wrench, oh, and them laughing at all the people that think RB25's will magicaly blow up over 400rwhp. That proves nothing. BTW, the shop owner has a stock bottom end in his RB25 with a built head that made over 600hp. "that's only an average btw"? What? Your not making sense. I'm asking if you have seen an RB25 blow up, seen one sitting in the shop getting fixed, or heard actuall detailed "this is what broke for this reason" stories. I'm talking like "the block split" or "thing ringlands cracked" or "he lifted the head and blew the gasket which trashed the motor" kinda stuff. Your friends telling you RB25's aren't reliable over X amount of HP because they said so and they own a shop so it must be true doesn't fly with me. I'm not trying to turn this thread into a "post count measuring contest" which it seems all these threads about what RB25's can make always turns into, I'm just trying to get hard evidence either way. So far I've seen numerous people posting up that they have been making 400+rwhp for years on stock RB25's, and not one person saying "I blew my RB25 up". I'm sure there are plenty of people who have blown them up, but I'm willing to bet most of them just had crappy tunes, not enough fueling, etc and had nothing to do with them breaking just because of HP.

I completly agree that AFM's are just a supporting mod, and only allow you to MAKE more hp, but aren't the Z32's a bigger diameter? If he had the piping to match them, I'd think he could expect a gain. Different situation from most of the other "will a z32 give me more power on my GTSt" threads.

And what hard info are you basing this off of? Repeating what you hear on the internet doesn't count.

make a mark on the CAS and the timing cover, and put it back perfectly lined up so you don't need to reset the timing and your good

Depending on the mounting location of the wastegate though, they aren't really hard to change. If it was a matter of keeping my project off the road for a few weeks, I'd throw the .6 spring in there. If it's a couple of days though, or the wastegate is a pain in the ass to get too, wait for the .9 spring.

holset hx-35

You won't be able to boost as much as you want. Your boost controller can only go so much over what the spring naturally opens at. It depends on a few factors like how strong your boost controller is and some other stuff. Ballpark, I doubt you'll be able to go much over 1.3-1.4 bar on the .6 bar spring, if that much.

I was running a stock one at 1.5 bar for well over a year at that power level. Now I have a 1.2 tomei and cranked up the boost to around 1.7-1.8 bar if I'm on the Japanese high octane gas, not base gas.

no

Mine's still kicking just fine. No dyno sheet, but it's right at 500rwhp judging by the 5v's on the Z32 and 120mph trap speeds.

Close It's all RB25, including the head. It's an adapter to keep the ITB from the RB26, and like you said, the covers bolt right on. I did have to trim the "ears" of the backing plate some for the timing cover to fit. That's got to be tough to make it say RB30. Would you add extra material with a welder or somthing?

Notice it doesn't say RB26

Yeah, to bad for me I wonder how much power those adapters are good for? Also, I can't seem to find the adapter from pro engines. Any links?

How do RB26 valve covers compare to the above mentioned? Just curious--I'm running those on my RB25.

Thanks for all the good info guys. Sounds like the adapter is the way I will be going. I'm avoiding the stegea motor if I can because I already have several 2wd RB25's sitting around that I know are good, and it makes replacing popped motors much cheaper. Stegea motors are EASIER to find over here, but still not easy. I've only found 2 in 2 months of searching here on Okinawa, but both of them are in vehicles that the junk yard wants to sell the car as a whole. Also, since I already have 2wd RB25's, all I need is around $700-$800 USD (?) for the adapter, instead of $500-$800 for a stegea motor which if I blow it up, I'll have to find another one, instead of using the ones I already have. Is there a lot of other machine work or modifications to the block needed after the adapter install, or is it just a matter of dropping the pan and swapping the motors?

That's the kinda info I was looking for. Thanks!! Isn't the GTR gear box the same exact thing as the GTS4? Strength and all?

Do you still have the 2wd to AWD black adapter? Any clue if it would work on a RB25?

I already have a pretty nasty R32 GTSt and have found this GTS4 in awesome shape for $600. It's different, it would be a sleeper, and we have a thing for making big power with stock/cheap RB25's. That's why. I'm not really looking to debate the merits of GTR vs. making this work. There are a ton of 500hp GTR's that I walk all over all the time around here. GTR is a better base, I agree. If I can make 2wd RB25's work, it's a better option for me for what I want to do.

After a little more reading of threads, I've seen mention of an adapter plate you guys have over there for making a non AWD block work with AWD. Any links for these? I realize it will make the motor sit up higher, but I am already running an RB26 ITB intake manifold with an adapter, so hight isn't a big issue with me. It also allows me to still use the plentiful cheap RB25's over here instead of relativly rare and expensive stagea motors. We are really pushing the limit of stock RB25's at the shop I go to. The guy is my good friend too so it's kind of an experiment he would be interested in and I get pretty good prices on work. The shop owner currently has a stock RB25 bottom end pushing 650hp, and I'm mid to high 500's right now. We have a couple others making mid to high 500's also for a couple years. I know how crazy you guys think we are for pushing 25's that hard, but when they are $300 a pop and I have 2 good ones sitting here, it's a chance I'm willing to take. More info on the adapter plates please!

I'm very interested in this. I've got a R32 GTSt up around 500rwhp with an RB25. My friend just picked up an emaculate 1994 (didn't even know they still made R32's then) R32 GTS4 with a sunroof for $600 USD that I found for him, and he will be obliged to sell it to me for that much in about 4 months. I want to find a way to put a RB25 in that bugger so I can swap all my stuff over and have a nice little sleeper. RB25's are a dime a dozen around here (not Stagea ones though), so I'd much prefer that to a RB26 which runs $3-4k even over here. I'm also having pretty severe traction issues even with drag radials (it's a drag/corner carver car), so this would really be a fun project for me. So what are my options for the GTS4? -Stagea RB25 -RB26 -? -? -AWD/2wd block adapter (have no info on them)

RB26? I know a lot of people here on Okinawa running the stock RB26 intake around 600rwhp. You should be fine. I'm not saying a greddy intake wouldn't be better, but I don't think the stock one will choke it to bad. Do they even make cheap china greddy copies for the RB26?

x2 500rwhp @ 1.8 bar on stock coils. The only reason people see a diference going to splitfires is because thier old coils were dirty/busted and the splits are new. I did the dremel the inside trick and they were like new.

Truth be told, I've never heard of Jim Berry single plates (I'm in Japan) so I can't speak first hand of them. The clamping pressure must be huge on one of those. I know there is no Jap super single that could do that (ORC, OS GIKEN, etc.). I toasted a 1 month old ORC with just a RB25/TO4e on the initial tune! I run a OS Triple now.

DriveshaftS? Are you talking about the half shafts coming off the diff to the wheels or the drivshaft from the tranny to the diff? What kind of power are you making with what kind of tires on a 2wd that you need to be worried about either?

330rwkw is twin plate on a 2wd. 330AWkw is probably going to be getting close to triple plate territory. No way a single would hold that kinda power.