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Isn't 8500 revving quite hard for a stock rb25? Have you tried with a plumb back to see if the inter-gear lag improves?

Its a Neo with valve springs and cams. 8500 seems to be the sweet spot.

I assume you mean plumb back waste gate? No I haven't, but I can't imagine that would help?

Might not, i always plumb them back anyway after on one of my cars i tested one to vent, plumbed in, and not fitted

at all, drove much nicer plumbed in , and seemed to have lotter better response after gear changes

cheers

darren

Did you not hear the the sphincter of the universe gobbling away in your engine bay on gear changes?

Lol!

No I meant plumb back bov. I have run mine blocked for the flutter noise ages ago for shits and giggles because the rb25 bov was leaking. Then when I could afford rb26 one I put that on. I think that no bov slightly detriments between gear response. I'll try get a video of mine up over the weekend of my boost gauge to show you.

Lol!

No I meant plumb back bov. I have run mine blocked for the flutter noise ages ago for shits and giggles because the rb25 bov was leaking. Then when I could afford rb26 one I put that on. I think that no bov slightly detriments between gear response. I'll try get a video of mine up over the weekend of my boost gauge to show you.

you are certain the rb25 BOV was leaking under boost? whats with everyone saying they are indestructible and can handle 11ty million psi?!

In that case no, haven't tried. Bov hasn't been on since I did the Plazmaman plenum. Need to get some piping made up, but my fabricator is no longer in the business :(

That's what my tuner was saying at the time. 25 bov was leaking during WOT on 98 tuning, so they blocked it to complete the tune. I then bought a 26 one, as that appeared to be the one that had the "bulletproof" reputation on the forums for big power/boost. No problems with it at all.

My searching on here told me the 25 one was suspect with anything above std turbo. I could be wrong.

Hanaldo from those video's you need to drive more agressively and keep it in gear for longer. Going into 5th is a waste of time on the strip. For example my first few runs were similar to those, wasn't revving all the way out/changed gear fairly slow then i changed my driving style and ran 7mph faster traps.

Hanaldo from those video's you need to drive more agressively and keep it in gear for longer. Going into 5th is a waste of time on the strip. For example my first few runs were similar to those, wasn't revving all the way out/changed gear fairly slow then i changed my driving style and ran 7mph faster traps.

He said that he is revving it high and only changed to 5th after the line..?

What do you guys mean by driving more aggressive? Is he meant to be smashing it into gears

Hanaldo I think this is more the shifting they are talking about. I remembered this r34 they built back in the days of HPI dvd's.

Skip to 27:00 and watch the shifts. This is a 294rwkw r34.

Dyno tuning and chart at 25:30

Edited by copycutter

He said that he is revving it high and only changed to 5th after the line..?

What do you guys mean by driving more aggressive? Is he meant to be smashing it into gears

8500rpm in 4th gear changing to 5th? car would be doing ~220kph or so based on stock gearing. Don't think so, also gear changes are very slow and launch is very mild. Driver skill is more important than power, i raced an XR6t at WSID and was neck and neck with him the whole way down, not because my car is fast, but because he couldn't drive for shizz. When on boost he would pull a bonnet ahead then change gear ever so slowly and i would reel him back in and it would go back and forth to the finish line where he ended up doing 1 tenth quicker and only 3mph faster.

yeah i was going to say, is the tacho right? It sounds more like 6000rpm... and if you shifted to 5th just after you crossed the line then surely you crossed the line at over 7000rpm in 4th, which would be over 200KMH in an R34 anyway (120MPH) unless you have a 4.3 diff in it...

I got mine running again today. 3.6 diff in the bin and sporting a 4.11 and twin plate clutch now, its a completely different car.. traction is a nightmare. Im thinking when I go to the drags im not going to bother trying for a time, just gonna smash and grab for a MPH.

That's an interesting point, I don't actually know if my tacho is correct. But in any case the shift to 5th was well after the line, I didn't cross the line at 8000 in 4th. Don't really know what I crossed the line at, possibly around 6000. I just keep it going after the line just in case :P

Mmmmm I just watched the interior video again, that shift to 5th can't have been as far past the line as I thought. But it was I only time I did it, do I don't think it had any effect. That was actually one of my quickest runs.

One thing I noticed when I was going from my car with the gate plumbed in to atmo. I used to shift earlier with the atmo gate as it sounds like you are ragging on it so much harder when you are not. With it plumbed back I would hit the limiter more often. Strange but I suspect based on where its cracking gate in 1st gear that you are shifting somewhere well under 7,500rpm and depending on your curve you could be starting off in the next gear with 60rwkws less then if you used an extra 500rpm before shifting.

You really need to look at your power curve and gearing and work out the optimum revs for average spread of power. I know I had to rev my RB20 about 1,000rpm harger to have a real difference in power with the Plazmaman as under 5,000rpm it was generally lazier. So I used to hit about 9,0000rpm in 1st and every other gear about 8,300-8,500rpm to make sure it stayed on the boil

Maybe if you have a I phone or something, theres maybe a car style G-meter program /accelaration measuring app that you could use

to plot gear changes based on on g force or something( i don't know,just thinking out loud)

cheers

darren

yeah i was going to say, is the tacho right? It sounds more like 6000rpm... and if you shifted to 5th just after you crossed the line then surely you crossed the line at over 7000rpm in 4th, which would be over 200KMH in an R34 anyway (120MPH) unless you have a 4.3 diff in it...

I got mine running again today. 3.6 diff in the bin and sporting a 4.11 and twin plate clutch now, its a completely different car.. traction is a nightmare. Im thinking when I go to the drags im not going to bother trying for a time, just gonna smash and grab for a MPH.

Hey man going to be going to wsid on Sunday for the off street meet if you want to come should be good also no rush like wednesday nights cause it during the day

You should be in the 12s easy just try and get good rubber

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