Jump to content
SAU Community

Recommended Posts

Hey ppls.

Well, here's the story.

First time out, ran a best of 13.4 at 106mph.

No Major mods, stock clutch, stock turbo, computer, etc. etc. About 160 odd rwkw

Only mods were king springs and koni adjustables at the softest setting.

Hooked up to a 1.9 60ft. No Axel tramp, all good.

Next time out, new mods were Ogura Lightweight Flywheel, HKS Front Mount. 165 odd rwkw.

Couldn't better a 14.4 at some lowly mph.

Axel tramp to the shithouse, shuddering through gear changes etc. etc. about

Last night, new mods include PowerFC, bit more boost, etc etc 200 rwkw. Pineapples set to drag, Camber and alignment kit.

Again had problems getting it off the line, and through the gears.

Would either spin em up on the line and then have reasonable changes, or it would get off the line okay, and then when changing gears (esp into 2nd) it would break into axel tramp and bounce it's way down the strip.

Best time of 13.9 at 101 mph. This was with a long cool down (about 45minutes) and a good launch.

2.219 60ft (Crappy I know)

9.052 660 ft @ 80.68

13.926 @ 101.07 at 1/4 Mile.

$1000s of dollars to go slower! ARGH!

Why oh why?

I have wider tyres now, but no that hasn't helped.

My theory is that with the lightweight flywheel the car is too keen to spin en up and at I change into second, it break traction and bounces away.

Also, I noticed that when changing gears, unless I really really rushed it that the car would jerk back as I let the clutch out and put the foot down again. Again, I think that the flywheel is the culprit as there isn't as much inertia to keep the engine going and get that little jolt of forward motion as the clutch comes out.

Why couldn't I crack the 12s... I so wanna crack the 12s

Any ideas???

Do all you drag racers run light weight flywheels??

BASS OUT

Link to comment
https://www.sau.com.au/forums/topic/70559-bloody-drag-racing/
Share on other sites

your 60ft's suck

Maybe try lowering your tyre pressure . When you mod your car the charactaristics change alot and how you got off the line before might not be the best way this time . Practice practice practice starting by dumping at say 3500rpm's and work your way up the rev range untill the 60ft's drop . You may find that you need to ride the clutch alittle off the line for the best results and that may require a totally differen't rpm then when just side stepping , it's all about trial and error .

hahaha yeh I didn't want it to come arcross as harsh was a last minute post :cheers: . I've done worse in a 2wd car out at the creek so don't feel bad 2.260ft isn't all that bad for 2wd on street rubber but if you can get it down to 1.9 then thats about the best you could hope for on street tyres.

But then again hey all this advice is coming from a GTR owner us guys don't have any probs with 60ft'ers just everything else

:D

nar your a 10th off :cheers:. Hopefully next time out  might be able to see some 1.6's .

Kewl but

But then again hey all this advice is coming from a GTR owner us guys don't have any probs with 60ft'ers just everything else

This little RWD chicken runs 1.6's. Then again, hey all this advice is coming from a lowly gts-t owner, us guys don't have any probs with 60ft'ers :D

:)

Adrian

Nah it was good all night.

I had Wanli tyres on which I've been told recently are grippy as for a cheap arse tyre (were on the car when I bought it), and I started at a 13.7 and got to a 13.4 at the end of the night. The this ran a 1.9 60ft and launched hard. Dumping the stock clutch at like 6000 rpm.

That's why I'm so frustrated with the crappy times last night. My car is much faster now that it was, but the crappy times show that it ain't the best on the strip.

Rev210 picked up 0.4 of a second with the lightweight flywheel.... Why did I drop speed?

BASS OUT

Something else sounds up rather than just a bad launch and wheelspin, you should still be running, at worst, 106mph. Even when i had a shocking 60', wheelspin til 3rd, hot day, blah blah, i still ran the same mph of 114 even though my ET was 13.4. I also had a lightened flywheel, but it wasn't the cause of my crap times (best of 13.0@113mph).

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Hi Yes we're a bit optimistic we might get something out of sealing up the two pipes of the external wastegate and reactivating the stock one. I believe the orginal stock wastegate was tack welded shut. It doesn't budge and visually looks closed and sealed. The car has noticeably more lag so it could be at least part of the problem, maybe all. It's definately one of the key changes made since last tune. And it's one that's more difficult to fully understand and measure, not like for instance timing or cylinder compression.  Thanks for that feedback, we'll let you know how this progresses. Fingers crossed.   Regards Rob
    • Transplanting the vvt from a 25neo into an rb26?
    • Well, I was going to say, "Is the wastegate set up so that it is not leaking?" That's actually a different thing to what you're asking about. In theory, if you have allowed the two halves of the manifold to commmunicate (more than the stock manifold does - which is at least a little bit) then the negative effect should be apparent in delayed spool, not in outrigth power. OK, maybe just maybe, a badly set up twin scroll wastegate "crosstalk" might kill the top end, although it's hard to see how. What is happening with the original wastegate in the turbo? is it sealed off properly. If it's left flapping in the breeze, it will f**k everything up. If it is still there, and can be returned to service, I'd be capping off the external (presuming the two halves can and will be isolated from each other after doing so) and have a go with just the stock wastegate. I have an internal wastegate in my highflowed rear housing. The bigger opening and flapper should be fine to >250 rwkW. So there's not exactly a pressing reason to have the external. Done right, an external will give better results. Done wrong, it might just be possible to have worse results. Report back!
    • Hi Rob It's a nistune ecu. Yes same shop, good reputation. Apparently the computer on the dyno is compensated for temperature.    Chris was saying that the lean or richness of the mixture would be covered in the actual tune, but he's already picking up in advance that it's under what it should be. Regards the dyno, it's also noticeable on the road. But I just want to add something that has just come in, it appears there might be something in the setup of the external wastegate. In the exhaust manifold there is a centre divider between the front three and rear three cylinders. The external wastegate has a pipe from each side that join at the wastegate. Theory is those two pipes just might be pypassing that divider and introducing a problem somehow. Is anyone familiar with the divider in the exhaust manifold and the effects if the two wastegate pipes were to create a bypass path? Thanks for your questions Rob, interested in your thoughts on this external wastegate bypass theory. Regards Rob
×
×
  • Create New...