RB25det internals

[Largekid]

i have searched and have found not a whole lot on what i'm looking for.
i am looking for a place to get upgraded internals on the rb25, i was told they can only hold ~300HP, i am placing the engine into a 240 and am looking for close to 400+ at the begining. what are other mods done to the rb series to get it to this kind of power?
thanks

[moondog]

I hope they can handle more than 300 horse, cos I've probably got somewhere around that now, and I haven't done bugger-all to it. Sure they'renot as strong as an RB25, but they're not bad, afaik

[Largekid]

i guess you meant the RB26, and yea they can hold the 300 HP+ but i'm wanting to run like 425 for a while with out anything going wrong with it...from what i've read they don't hold high HP very well...am i mistaken??

[moondog]

Originally Posted by Largekid

i guess you meant the RB26, and yea they can hold the 300 HP+ but i'm wanting to run like 425 for a while with out anything going wrong with it...from what i've read they don't hold high HP very well...am i mistaken??

yah, I did

And yeah, 425 horse probably is too much for an internally standard RB25

[Largekid]

any ideas on where i should go to get the goods to make it work...i was maybe thinking cunningham rods for those, and everywhere else is pretty much up in the air...i haven't been able to find a whole lot about the rb25 as far as the internals come

[Largekid]

i read that i can use most of the GTR parts for the internals and it will lower my compression ratios and stuff like that. the pistons (86.5mm?), rods, and cams...i think i'll still go with cunningham rods I.E. 160 a piece being custom built and withstanding more that the GTR ones. but what else will i have to get to do this. i was told that ppl are selling there parts like crazy when the put the stroker kits on their cars. thanks for the info, you guys have helped out alot

[Doughnutdemon]

From what I understand you can use the RB26 crank, rods and pistons, but you need to machine the block (or the head, can't remember which) to get the compression ratio back to a decent level.

[RazorGTR]

You don't have to do the rods and crank for 425hp out of the RB25, they are plenty strong enough for that. If you want to start pushing high revs, constant 7,500+ then yes I would suggest doing the rods. The factory cranks would be more than fine for up to around 650hp. After that I am not sure.

JE forged pistons are a great upgrade and cheaper than Trust, Jun, HKS, etc. I would also change the rod bolts to ARP as the factory ones are a bit weak for constant huge power increases. A mild set of cams that suit a decent turbo that will flow that, and a front mount intercooler and you should have no worries.

[Largekid]

Originally Posted by RazorGTR

You don't have to do the rods and crank for 425hp out of the RB25, they are plenty strong enough for that. If you want to start pushing high revs, constant 7,500+ then yes I would suggest doing the rods. The factory cranks would be more than fine for up to around 650hp. After that I am not sure.

JE forged pistons are a great upgrade and cheaper than Trust, Jun, HKS, etc. I would also change the rod bolts to ARP as the factory ones are a bit weak for constant huge power increases. A mild set of cams that suit a decent turbo that will flow that, and a front mount intercooler and you should have no worries.

the rods i plan on getting come with fabricated bolts for the rods, i should go with JE pistons, and i was told to go with the Tomie PonCams, is that a good choice??? and after that i should be good to 400-50 HP

thanks for the help everyone

[S13GTR]

If you want higher revability I have a full set of valve springs and retainers for sale from my rb26dett. From what I hear you wont float the valves at 9k even with rb26dett valvetrain.

[S13GTR]

Actualy for that matter if your looking for hp's I also have a set of 440cc injectors for sale which are good for 450 to 500 hp's, and other gtr stuff. Let me know.

[RazorGTR]

Originally Posted by S13GTR

If you want higher revability I have a full set of valve springs and retainers for sale from my rb26dett. From what I hear you wont float the valves at 9k even with rb26dett valvetrain.

GTR valve springs, retainers, valves and cams are not interchangable with the RB25. Also the factory springs will not tolerate 9,000 rpms without valve float or bounce, whatever you want to call it.

The factory RB25 injectors are side fed where as the GTR 444's are top fed.

[S13GTR]

My bad. I have ben told wrong I guess. But I was almost certain the springs and retainers were, guess not.