Increasing redline on RB25

[JimX]

Is it safe to take the redline up to 7500rpm or so? With stock internals, and a PowerFC. I've got an adjustable exhaust cam gear so that should help with any breathing problems, but I'm also worried about affecting the longevity of the engine.

[N I B]

No problems with 7500 on stock inturnals we even have 2 engines on 8500 long term.

[JimX]

Ah good stuff. Might bump it up to 8000 then.

[Duncan]

Is it still making power above 7500? Normally peak is more like 6500 isn't it? or do you mean for flexability with gearing on the track?

[nv033]

No problems with 7500 on stock inturnals we even have 2 engines on 8500 long term.

what mods would these motors have or what power figure are they running?? ....could u define long term in figures as in months, years???

[DoughBoy]

Long term = completes a track session

Standard internals = un-opened motor

[R31Nismoid]

Long term = completes a track session

Standard internals = un-opened motor

always the realist

I took mine to 7500rpm no drams for over 12 months.

Motor died - but that wasnt due to revs, just a few too many psi snuck in one night and caused it to ping.

So 7500 all the way.

Although, i found with stock cams, the car didnt have any go after about 7300 at that was still pushing it.

Also due to many other factors aswell im sure, like ECU and all sorts of other things

[krzysiu]

There is no point at all to increasing the redline, You will lose so much power after 6500RPM that its not even worth it. It may seem like its still pulling but on the dyno it shows that the HP drops like hell.

[R31Nismoid]

joel doenst have a stock turbo, thats where the stocker runs out, with a bigger turbo i got to 7300rpm before i ran out of usefulness

[2rismo]

If the tuning is okay, 7500 wont be a problem.

Adrian

[JimX]

Although, i found with stock cams, the car didnt have any go after about 7300 at that was still pushing it.  

Also due to many other factors aswell im sure, like ECU and all sorts of other things

I'm only considering it because I've got an exhaust cam wheel, and will be running 15 psi after the tune. I used to run 15psi with the factory ECU, but the PowerFC at the same boost maxes out my injectors and AFM. So I'm running at 11psi until I get it tuned.

Anyway I'll see what the mechanic has to say when I take the car in. At least now I know I have some room to experiment.

[aridyne]

I've run my Skyline up to 7500 for over 9 months now, I have had no drama's with this setting, however yes in Dyno runs I have found that there is no real power increase around the 6500 mark. I am running a Haltech E6K I think with a Stock engine and turbo along with ARE intercooler. I pulled about 187kw out of the rear wells and about 1350nm of Torque which I thought was quite high but this has been verified by two different dyno stations.. Also running the stock turbo at 14psi with a 3" Dump running into a Apexi 3.75 cat back exhaust.. (yes it scraps everywhere). I did a recent check and found compression to be around 135-150 over all 6 cylinders.. I have been told this is about right for a skyline, I dunno? shrug I think that a GT2540 would be great to upgrade to with new 700+cc injectors with fuel rail and pump to be upgraded as well. What ya think? do you think a new Cam gears would be wise too?

Aridyne

[2rismo]

1350nm of Torque

Would you like to post the dyno sheet for this run(s)?

Adrian

[Abo Bob]

That's nothing.

[dojobi]

haha those 4 door R34s certainly put out some power

BTW that big 0 at the top was possibly the dodgiest effort I've ever seen.

[mokompri]

im pretty sure that 1350nm is tractive effort that its showing

get some cams, bigger turbine on the turbo, that should make things breath better up top and give some nice power in the higher revs :aroused:

[N I B]

This is for those that think that RB25s dont make a shit load of power and high revs on stock cams and heads.Check it out.

[Guest Robo's]

This is for those that think that RB25s dont make a shit load of power and high revs on stock cams and heads.Check it out.

That is nice and FAT

[N I B]

4th gear run so you can see from the speed that we are talking around 8k at the speeds on the graph.

[51jay]

The exhaust camwheel retarded 3 or 4 degrees is good for enhanced torque low and midrange. In all our dyno runs stock and modified power tended to drop off fairly sharply over 7000. In the early days we hit 8200 on a regular basis.....but not anymore. After 3 years of street/drag/track the engine still doesn't use any oil between 5K changes so I guess the revs didn't hurt it any. When you get it tuned and see your power curve then you can decide on your rev limit