Meaning of frustration

benm · February 23, 2005

10/03/2003 = 14.184 @ 99.94mph / 2.168 60ft

Mods done afterwards:

* 225/50/16 good Michelin Rubber

* Traction pineapples

* Koni Shocks

* Front/Dump pipe + Cat

* Bosch 040 Fuel Pump

* Daiken Organic Sports Clutch

* 10psi (instead of 7psi)

(13mths and 13 runs later)

14/04/2004 = 14.163 @ 100.20 / 2.166 60ft

Mods done afterwards:

* Greddy Exhaust Cam Gear

* Splitfire Ignition coils

* 9psi

(10mths and 3 runs later)

9/02/2005 = 14.145 @ 102.07mph / 2.167 60ft

(1wk and 3 runs later)

16/02/2005 = 14.009 @ 102.07 / 2.089 60ft

So basically i've done 26 runs and only improved my time by 0.175sec. My car grips better, holds boost better, is making 20% more power, is pulling harder on high boost, is launching cleaner and yet i've basically made no improvements on my time slip...

Every single nite I spectate/compete I see first-timers in R33 GTS-t's and 300ZX's with basically a fmic, exhaust and 10psi boost and doing the same 60ft and same TS as me yet doing 13.5's on their first nite, what gives?

Ok so i'm a granny shifter (so i've been told countless times) and i've been working on that over the past month (gained a whole 0.136) but their has to be more to it than just that. I can't be 'that' bad at shifting.

Tonight was my first time with some 245/50/16 Nitto NT555R's thinking they could nett me an easy 0.2sec (which i'm sure they will given another few meetings experimenting).

My first run I launched like normal (3,000rpm) and it felt like a very clean run (thinking mid-track that I was finally into the 13's) only to claim a 14.165 @ 99.26mph / 2.135 60ft. Then I dropped the pressure to 14psi (down from 20psi) and launched from 4,000rpm to get a 14.169 @ 98.41mph / 2.109 60ft. From their on it went down hill, tried launching at 5-6,000rpm but my sports clutch just cant handle the revs and heats up causing gear selection to be a nightmare.

I'm getting very close to looking for a new hobbie because the fun in this is quickly disappearing (along with my bank account)... might be time to dust off the golf clubs again

RNS11Z · February 23, 2005

benm, sounds fustrating?? I would say its your standard computer holding you back. Do you do burn outs before your run?? This may be the problem. This affects my s15. I found this out on the dyno.

1st run 180rwhp

2nd run 172rwhp

3rd run 168rwhp....

let the car rest for 5min, did another run got 179rwhp. At the track if i dont do a burn out my ts is 100-101mph. If i do a burn out my ts is 99-97mph. I figured the standard computer makes it run richer and pulls timing out when it notices abit of heat soak or stress on engine with out temp changes or something like that (not too sure on how it works). But this is my conclusion to why i dont do burn outs when i go 1/4mile. With the same mods i have now i have gone from a 14.2 @ 100mph to consistant 14.1 @ 99mph to a best of 14.003 @ 101mph. 60ft was 2.2.

I have seen skylines on dyno's and id say the standard dip in power @ approx 5-6k is what holds most back.

Gl with the 13.

benm · February 25, 2005

No doubt it is my standard ecu holding me back, but it also should be holding others back although it isn't.

For the burnout I basically just scrub my tyres to remove the water from the burnout area. I do the same 60ft times regardless of if I do a burnout or not which is funny (2.0xx/2.1xx).

Also don't forget that I have 266rwhp, not 180rwhp

Abo Bob · February 25, 2005

I think you should let Adrian or someone you know who drags a bit do a run in your car to eliminate at least one variable.

Are you removing your spare and other junk from your car?

I have a 4 door (read heavier than most other skylines) and less power than you and got 13.8 but to be honest I was a little dissapointed I couldn't get any lower than that.

I did 30+ runs that day and even though it's an auto and should be easier I was surprised how I got a fraction better every run or 2nd run. Started in the 14.2's and eventually 13.8.

benm · February 25, 2005

Adrian has had afew runs in it, from memory his best was ~14.1-14.3sec

Buster has also tried

Jordan · February 26, 2005

How stiff is the supension? You say you have Shocks and "Traction Pineapples" (WTH?)

Maybe its a bit too stiff in the rear end? You ideally want some sqat when you take off.

Let me have a drive of it? always wanted to feel what 266rwkw feels like, my best was 207kw on a dyno years ago.

benm · February 26, 2005

The rear has 18mth old Koni Adjustable Shocks (what is adjustable I cannot workout)... unsure what springs. The pineapples give better squat.

Also it's 266rwhp (198rwkw) not 266rwkw.

Roy · February 26, 2005

Bugger...You have close to 200rwkws and you can get off the line well enough to pull a 100mph trap speed.

I dont know a whole lot about drag racing, but with 200rwkws, (maybe 10 either side of that figure) i was pulling 108mph with a slipping clutch.

If i hadnt been in your car i would say that the dyno is telling fibs, but the thing definitely has the grunt:confused:

I suppose the silly questions like are you reving the things ringer out, short shifting?

Even if you did go nice and easy on the gear changes with the sort of response your engine has id say that it shouldnt be too much of a concern as the thing isnt going to fall off boost:confused:

And Adrian could only do a 14.##:confused:

I would have thought with that 60ft time all the hard work is done, just row thru the gears as quick as possible shifting at 6,600rpm and you would see a 13.

What sort of things affect the mph? Are you sure the clutch isnt slipping. Mine was slipping and it was so subtle i couldnt really pick it, the engien just felt a bit flat coming on to boost as it didnt hit hard as usual. A few runs later it started flaring and what i though was wheelspin in 2nd and 3rd was clutch slipping in 2nd, then 3rd and after about 6 runs into 4th:(

Something is slowing you at the top of the track. Bump tyre pressure back up to aroud 30psi hot. Walk the thing off the line with minimal riding of the clutch and see what mph you run ... lol make sure your handbrake isnt on.

Actually just go to Wakefeild, where a 14.1 is a top time, 1 minute 14:)

relicr31act · February 26, 2005

Put someone in the car that doesn't granny shift and see what the difference is. Sometimes the culprit is the nut behind the wheel.

benm · February 26, 2005

Roy: It's pulling harder and making more power since you last drove it. Greddy Ex Cam Gear and Splitfire coils have been done since that night you drove it.

I change gears up around 6800-7000rpm as quick as I possibly can. With the nitto's it chirps every gear the whole way so I don't think i'm granny shifting as such. I dropped into SBC (St Marys) about 2wks ago and got them to look at my clutch (just to check it was ok) and the mechanic jumped in and played around with it and said it was grabbing fine. I've found that it sticks abit with too much rpm (either from the burnout or the launch).

My problem isn't the top of the track (102mph) its from 60-660ft. I'm doing the same 60ft and TS as other people that are doing mid 13's it's just the bit in between that is costing me time.

If you click here you can see the detailed info of all my runs.

Roy · February 26, 2005

So where is the mph going? My car with about 200rwkws (had a miss at high boost so was running about 14-15psi)

I cant launch the best so my best 60ft was a 2.253sec, my 1/8 mile time is 8.891sec and 85.5mph. That was for a 13.4 @108mph. It was my 2nd ever run, and every time i tried to launch harder the clutch slip just got worse:(

That is i suppose with a little less weight, but similar power, similar clutch and i was using DO1Js so should be similar to your Nitto times.

Dont people always say that mph is the best indication of power. :confused: Maybe try sifting at 6,500rpm so that you are staying in the meat of your powerband?!? Do you have a piccie of your dyno chart

benm · February 26, 2005

I cant launch the best so my best 60ft was a 2.253sec, my 1/8 mile time is 8.891sec and 85.5mph. That was for a 13.4 @108mph.

2.089sec

9.080sec

76.77mph

14.009sec

Your car kicks in mega hard though compared to mine which kicks in much earlier but very gentle.

And below is a pic of the dyno graph when you drove it (the blue "before" line)

Roy · February 26, 2005

Hey Ben, PM me your email or just drop a line to [email protected] ans ill send you a spreadsheet that theoretically shows you the optimnal rpm points to change gear at

oh and include the tyre curcumference (do a search) or just tell me the rear tyre you are running and ill approximate:)

Roy · February 26, 2005

Actually, there is no real point, your thing makes power to redline...so changing at 6,800rpm doesnt seem to be a problem.

Meh, i got no idea. Do you have any wheelspin probs? I reckon the best person to be speakign to is Robo's. (12.98 @ 107.2, 2.02 60' with Stock Turbo, SAFC ) I seem to think its either a weight thing (but your car doesnt have 100kg worth of stereo) or a power or clutch slip prob. Robo was getting similar mph to me :confused:

Meh, stop thrashing that poor diff, clutch and grearbox, head down to Wakefield..you know you love it:)

benm · February 26, 2005

Well i'm heading off to Oran Park now (to spectate)

Trust33 · February 26, 2005

Hmm if you look at my dyno in this thread you will notice,when compareing your old dyno 185rwkw,that from 80kph is even,100kph is 10kw more to me,120kph is 30kw more to me,140kph is even,160kph is even.The red line was the old 160rwkw power figure.

I was running stock turbo,pfc,stock cast dump with cat back zorst,Badly slipping clutch,gtr pump,adj fpr,small front mount and an ebc also had 17's with 255 rears and even tried stock 16's with 235's rears and it made no difference in times or top end.

When i took it to eastern creek back in the day it ran a 14.7 boosted with stock computer @ 160rwkw.

Then went back with the current tune 182.0rwkw and pulled a 14.2 @ 99mph with a dodgey slipping clutch that i had to baby off the line to get it going It was like i was taking off at the lights on the street.

What im getting at is the pfc made a hell of a difference to my time.A 1/2 a second is a great improvement.now coupled with a clutch to boot i am confident of a mid to high 13 sec time slip @100+mph.

Get a pfc and see the difference that it makes to your current tune.As you can see in my dyno there is an average of 15-20rwkw throughout the entire before and after.

Though seen as though u allready have 198atw it may not be such a dramatic difference in power.Try to keep the revs in the power band.And when you feel the power drop off it means that you have left the power band so you hsould have shifted a few hundred rpms earlier.

May i suggest what ppl have been saying to do is soften up the rear end for the drag strip and let it squat more off the line.

Trust33 · February 26, 2005