R.I.P.S RB30 runs 8s with 1.4 bar, street tyres, gasoline, no NOS

[trackday addict]

- now that is an incentive to get off the line quick
Be amazing to line up with him though Rob, one you'll remember for a long long time

Originally Posted by R.I.P.S NZ

Judging by the way that car uses all of his lane its probably better that he will be WAY out ahead of me, lol.

Can't wait.

Rob

[Boosted]

Originally Posted by R.I.P.S NZ

Judging by the way that car uses all of his lane its probably better that he will be WAY out ahead of me, lol.

Rob, after watching your last run, I'm sure Reece is thinking the same thing about the 240

[Lith]

Originally Posted by R.I.P.S NZ

I'll be there with bells on and I'll actually be racing in the same class as Reece I believe so with any luck I'll line him up at some stage, I'll get my ass handed to me on a plate but I won't care one little bit cause I'll be able to say "I raced the HT GTR in a proper Pro Import race and have the vid to prove it"

Judging by the way that car uses all of his lane its probably better that he will be WAY out ahead of me, lol.

Can't wait.

Awesome, sounds like this weekend is going to be fun on so many levels. Keep us updated I can't imagine it being anything other than a bit intimidating having that thing lined up in the other lane.

[Boosted]

I sure wish I was in NZ this weekend

[R.I.P.S NZ]

Quick report back from the Nationals.

1st round of qualifying was against Reece

A couple of nice burnouts and we came into stage together, all I can remember is not being able to hear a thing with all the banging of his launch control, he crept forward and left early, I cut a 0.067 RT and violently tyre shook my way to a (1.55 60ft) 8.97 @ 162.96 while watching him just vanish into the distance.

Its a shame we didn't leave together, it would have been cool to be at least "close" to him for a while but I suppose I am one of a very few people who can say they raced Reece and won even if it was under unusual cirmcumstances, Reeces pit was next to ours so I went over and we had a laugh about it afterwards.

We sustained alot of damage to the 240 on the first pass and the tyre shake it had was extreeme to say the least, in fact some of the old school V8 guys said it was the worst tyre shake they had ever seen. even at 1/2 track onwards I was playing with the trottle to try and get rid of it but as soon as power was put back on it shook hard again.

The rear view mirror flew off the winscreen and smashed into the rear hatch window, both doors are damaged and now don't close properly, both rear guards are damaged behind the tyres, the petrol flap opened itself even though it seems impossible for it to do so when looking at it afterwards, the laptop for data logging shutdown due to the shock, the rear wing broke, the wheelie bars were bent, the turbo moved about 15mm accross and hit the bonnet and all in all it was a terrible run with alot of pedling going on.

We fixed the wing (big thanks to Adam Wigg for the stainless bolts) changed tyre pressures and turned the boost down and went out again for our second qualifying pass.

Massive tyre shake again (1.48 60ft ), more damage to the body, the badges fell off onto the track, the taillight surround came off, more damage to the doors and although I backed out of it early in the run and was about 5mph down at 1/2 track, I eased back into the throttle and ran through for a 8.840 @ 164.55mph.

I noticed the shift light was on in top gear WAY earlier than usual and I hit the limiter well before the finish line, it turns out the transmission was shot and on my 3rd qualifying pass I had almost no reverse after the burnout, the transbrake didn't work and when I did roll away gently to do the run I had no top gear so the 164.5mph was actually pretty good considering it was a on and off the throttle run, low boost, with massive tyre shake and a stuffed trans.

On the trailer, drink some beer, have a bbq, drink some more till about 2.30am, sleep under the stars and get VERY cold, get up in the morning very second hand, watch some racing and think about what might have been if we didn't get that DAMN tyre shake and if the trans had have lived.

The trans guy came and took a look and he's pretty sure we are putting too much power through it for its current build spec, its the same old trans that came with the car and we hadn't touched it so I spose it did OK.

Got to love drag racing. (Sarcasticly)

I'll get some pix and video's up tomorrow, time for some sleep.

Rob

[M SKinner]

What actually causes tyre shake?

[R.I.P.S NZ]

Originally Posted by M SKinner

What actually causes tyre shake?

There doesn't seem to be a definative answer but I'd love to know how to fix it in our car thats for sure casue its doing my head in.

We tried higher tyre pressures, lower pressures, had the suspension geometry all setup by a pro, changed shock settings etc and nothing made any difference.

The shake is so bad it honestly feels like a bomb going off inside the car when I take my finger off the transbrake, the whole car just shakes like you are driving over massive potholes at 100mph.

We are still on DOT street tyres and we don't have bead locks, maybe we are just trying to put too much power through the body, its only got a real basic 6 point cage which isn't tagged to the body, no bars supporting anything in the front at all so god knows whats actually happening when we try to leave with full power.

Any idea's anyone????


Rob

[SteveN]

Go on to the forum on YB.com - Where the weak are killed and eaten and ask there, I'm sure you will get some serious help from people in the know.

One of the guys on there has a RB26 240Z drag car too!

[GT-R Glenn]

Whats changed since last time you ran it ?

[R.I.P.S NZ]

Twwenie has put forward an indea that the transmission has been on its way out for quite some time and as it deteriorates they are known to cause tyre shake.

It does seem to fit into with the symtoms we have been experiencing over the last 2 or 3 meetings and its also got notably worse since we have wound the power up some more, it would also explain the lack of mph V finish line rpm we have had.

The trans is history anyway, so we'll get it sorted and not change anything else and see how it goes.

Any more ideas/thoughts/donations () greatfully received......

Rob

[R.I.P.S NZ]

Originally Posted by GT-R Glenn

Whats changed since last time you ran it ?

Nothing except about 400hp more off the line.

We had tyre shake last time out but it was FAR worse on the weekend.

The mph has been well down for the rpm we've had through the line and it has got progressivly worse as we've added power so it may well be the trans was sh*ting itself and causing the tyre shake the whole time.

We made quite big changes in 2 areas on 2 seperate runs to see if we could get a sudden change and neither changes made any difference where I'm pretty sure with a healthy transmission they would have.

On the 2nd qualifying pass I had huge rpm well before the finish line and only got 164.5mph so there was clearly massive slip somewhere and I'm pretty sure it wasn't tyre spin.

On the 8.80 I backed on and off the power several times and as the power came on it would vibrate (like a soft tyre shake) and the shift light would come on and off from 1/2 track onwards so I suppose its quite pleasing to get the 164mph under those conditions.

Rob

[Lith]

Bugger

Bad news and good news then I guess - stands to reason with a holding on trans its going to hook up well, and putting all the torque through she's clearly got >165mph in her.

What trans was it again, some built TH series aye?

[R.I.P.S NZ]

T400 with a good valve body and transbrake, good race converter too.

[plumwerks]

Maybe time to ditch the dot tires too Rob,you've definitely got the power,so maybe time to get real serious about laying it down.

[R.I.P.S NZ]

Originally Posted by plumwerks

Maybe time to ditch the dot tires too Rob,you've definitely got the power,so maybe time to get real serious about laying it down.

Agreed, we have done what we set out to do on DOT tyres so I'll go to slicks and bead lock rims as well, but I still want to try it exactly as it was with the new trans only.

Everyone in the know I've spoken to thats seen the car run said we easily have the power to run 1.2 60fts and 7s / 170+, we just have to sort all the crap out, get away well and keep it in a straight line.

More data from the dyno the other week also suggests the trans was slipping as on the higher boost runs the mph didn't match the rpm compared to lower power runs earlier in the day, we also noted that we got LESS boost when trying a full power run with a 50 of NOS, this is totally against what we have found every other NOS power run so maybe the trans slip didn't load the motor properly to build the extra boost.

Our 937whp at 27psi might have been a little low afterall, the trans when fresh was built to take 1200hp, we'll try to run it up on the same dyno with a fresh stronger trans and see how it compares.


Rob