Rb25det & 8500 Rpm

[Guilt-Toy]

I been tuning a built RB25DET at a country next door, Engine is of stock configuration with built internals with a big turbo charger. Bigger then T04Z and smaller then 42r...

We need to rev this thing to 8500rpm to get things happening.....

I have advised the obvious, Balancer, Oil Pump.... But we need to come up with a decent head build.

Head porting is a issue. No one here will be able to port a head and get good proven results unless its a big F off fluke, and we are not going to take these chances. Because lets face it.. Around these parts of the world... To get a spare RB25 head? it will have to be imported from Japan and the cost of that would be of 5 heads back in Australia IF we are lucky.

We want a decent head build combo that will give us revs, does not matter if we have to go solids ors 280 cams. Customer wants a fast RB25 and he knows he needs to spend some coin to get it.

SO... What do we need to do to a RB25DET head to spin it to 8200 - 8500 rpm.

Please, No amature comments, if you have not done this before and have no experience then do not post crap in this thread. *nice tone of voice*

Yes... I have searched.

Cheers

[TiTAN]

send Fineline a PM, he is building a nice solid lifter RB25 head at the moment for his car.

[GTS-t VSPEC]

I rev'd the stock head to 8500rpm, and now that it's ported, bigger cams and Tomei valve springs we go to 9000rpm. Had this with a TO4Z running 600rwhp. Still using stock hydraulic lifters, had considered the swap to solids, but was alot of extra $$$.

[Guilt-Toy]

9k from hydro's ?? are you serous?

wtf?? We want to build it once.. Do not want to do it twice.

[GTS-t VSPEC]

9k from hydro's ?? are you serous?

wtf?? We want to build it once.. Do not want to do it twice.

Yep, and it's been around the circuit for heaps of laps (100+ at full noise). Lasted like that for 3+ years so far.

[WARLORD]

hks 256/264 h/d valve springs revs 8500 rpm all day and ive done 30,000 km on it with 100 passes at the drags its a good combo.

jim at crd tuned the car he wanted to go past the 8500 rpm cos it was still was making power but i dint want to.

Edited June 24, 2010 by WARLORD

[FineLine]

Drop Dan of ERD fame a pm GT, he is taking care of the details on my head.

Do it right once indeed mate, I did it wrong first time round and it was a very expensive excercise.

[STATUS]

Decent cam profile and springs is the key and it will be fine, i prefer to use lighter retainers but they are $850 for a kit which includes titanium retainers and springs. Lifters obviously need to be healthy to start with.

I have a 25 head here atm which has been CNC ported and has camtech 272's and the HD springs and Ti retainer kit 9k rev limit, its a relatively new combo so i will let you know how it holds up..

on a side not how is Georgia treating you? i havent had much of a chance to chat with the shop being so busy... i apologise.

[Guilt-Toy]

yeah good mate!

Do you think 264 with 9.3 mm lift and some spings should do the job nicely? what kind of oil pump do you suggest

It is a GT37 turbo, and it suffers from compressor surge a fair bit.

Decent cam profile and springs is the key and it will be fine, i prefer to use lighter retainers but they are $850 for a kit which includes titanium retainers and springs. Lifters obviously need to be healthy to start with.

I have a 25 head here atm which has been CNC ported and has camtech 272's and the HD springs and Ti retainer kit 9k rev limit, its a relatively new combo so i will let you know how it holds up..

on a side not how is Georgia treating you? i havent had much of a chance to chat with the shop being so busy... i apologise.