Tips For Doing A Good 1/4Mile

[AngryRB]

Doubt it'll make a difference mate as soon as you hit 4000 it'll just spin then as well.

Infact off the line it might even spin a bit anyway. Wheelspin is fine, you are on street tyres so you cannot expect it to launch perfectly.

Just try a bit more right foot/left foot control with throttle/clutch. Combine that with you 16s @ 20psi

I reckon you could improve. Practice makes perfect anyway. Don't expect to be running the best times until you've done a good 20 passes and really worked out the feel of the car. Manual racing is quite difficult too compared to Auto.

yeah very true, im just hoping to equal my previous atleast and maybe 13.5 with a decent take off, i dont think the tein coilovers are doing any favours , they are as stiff as anything and bouncy on the street, but will my best with practice and report back..

will have some fun anyway, thats what its about lol,... give them hell! or as close to it hey..

[AngryRB]

With 220rwkw and a 1400kg car (without me in it) this was the best i could achieve

ET: 12.9

MPH: 109

60ft: 1.9

This was using 225 street tyres, 16inch wheels and 20psi. I had a perfectly working LSD too, which is important.

I was also using rock hard coil overs.

Must have done at least 60 passes, could be 80 or more and had a lot of runs between 12.9 & 13.1 so it was consistent.

Without providing the following info we really cannot help you workout where you are missing.

MPH:

ET:

60ft:

Power:

Don't expect just to be able to put the foot to the floor as well. It's not a GTR

My passes required careful throttle control and use of clutch and not always 100% drop clutch and plant foot.

1st pass

MPH-94

ET14.721

60ft:2.383

Power: 214rwkw 1Bar

tyre pressure : 30psi

2nd pass

MPH: 99

ET: 14.773

60ft: 2.476

Power: same

tyre pressure 20psi

track temp 11degrees

humidity 44

for comparison, other guy (looked like a hilux ute with V8)

MPH:114

ET: 11.876

60ft: 1.684

Power: shit load lol

Do you think have a smallish turbo like mine, 2871r is the problem?? too much bottem end power instead of comming on late once the cars got moving??

Edited July 17, 2011 by SliverS2

[owen25det]

Hey guys,

went to the drags last weekend and was quite dissappointed with my time, embarrassed actually, lol... after previously doing a 13.8 with 195kw and crap suspension and tyres, i couldnt seem to get any better than 14.5 and i think its due due to the wheels spin/take off...

the car has much more torque and pull than before so i was expecting a low 13 as others were doing with similar power, a few things which have changed are, 18inch rims instead of factory rims, pwr fc, more boost, tein coilovers instead of worn out soft ones, heavy duty clutch instead of dying old one.

any suggestions ?? even on 2500rpm i was spinning them when the 13.8time previously was hardly any spin and all acceleration..

i noticed a 450hp r33 gtst doing mid 12's with massive wheelspin ,

all you need to know really is for drag racing applications;

soft susspension front an rear for maximised weight distribution,

larger sidewalls over low profile, again for helping shift the weight and applying tourqe to the ground..

correct tyre pressure for the tyres being used (low tyre pressure not always best)

an if et is what your after an you are using street tryes, an most semi slicks NO or minimal burn out..

and although it may be rough on the clutch,

riding it out of the whole untill you feel the bite then stepping off it..

with every pass you do observe things like rpm at launch an what you are doing with your launch weather you are dumping or riding your clutch,

an only after a few runs will you find how to get the best launch out of your set up..

[R31Nismoid]

Your 60ft's the what is hurting you mate.

2.4 is really average at best. Are you just dropping the clutch? Or feeding it in?

Get the 60ft down to 2.0 and you'd be prety close to a 14 flat.

However in saying that, there is no way you have 215rwkw with only 100mph. Its more like 170rwkw as with 220rwkw i was running 109-111mph. 10mph more, with a weight that would be very close to that of a R33.

So definately you are down on a lot of power for such low MPH assuming you aren't backing off before the end etc.

[AngryRB]

Your 60ft's the what is hurting you mate.

2.4 is really average at best. Are you just dropping the clutch? Or feeding it in?

Get the 60ft down to 2.0 and you'd be prety close to a 14 flat.

However in saying that, there is no way you have 215rwkw with only 100mph. Its more like 170rwkw as with 220rwkw i was running 109-111mph. 10mph more, with a weight that would be very close to that of a R33.

So definately you are down on a lot of power for such low MPH assuming you aren't backing off before the end etc.

well ive got a dyno sheet saying 214kw and an old one saying 195, i think its fairly accurate,

i was trying to feed the clutch but it kept gripping and spinning the wheels , ive changed the avcr setting to -50% duty and softened up the tyres and suspension and seems to be launching better now, so will attempt again in the next few weeks

[R31Nismoid]

Dyno sheets mean nothing, MPH is a very good indicator of how much power you have.

Fact is with 5rwkw more, I was running 10mph more than you... That is a massive discrepancy.

You are 100% down on power, or backing off before the end.

I bet your MPH hardly changes on your next outings. A 220rwkw GTS-t should be running 13.0 all day.

[mad082]

what mods were changed to get you the extra 20kw? was a dyno run done immediately before the mods to see what the real gain was, rather than comparing an old graph to a new graph?

and have you overlaid the 2 graphs to see if you are down on power through the mid range at all?

maybe put it on a dyno at a different workshop and see what power it makes there. may possibly show that your 215kw isn't quite accurate.

[Rekin]

Have read a couple of other car forums about drag racing.

The majority say that proper take-off on drags involve a lot of riding the clutch.

To control wheel spin you ride the clutch, not back off the accelerator. Get used to the smell of clutch if you want a great take-off

[AngryRB]

what mods were changed to get you the extra 20kw? was a dyno run done immediately before the mods to see what the real gain was, rather than comparing an old graph to a new graph?

and have you overlaid the 2 graphs to see if you are down on power through the mid range at all?

maybe put it on a dyno at a different workshop and see what power it makes there. may possibly show that your 215kw isn't quite accurate.

when i got the 195kw it was a stock computer without any tuning, the 215kw was with adding a pwr fc and tuning on 1.25bar but it was dropping off to 1bar by redline and also with splitfire coilpacks and walbro pump added

i will try again cause i feel like it has the power to do alot better, the launches were all spinning in first gear, even second and chirping third, so its all to do with the take offs, power is there to do alot better..

the 214kw graph is alot steeper and heaps more torque and earlier too, and on the road it pulls alot harder than before which was lacking, so i dont doubt the tuner or the graph...

Edited July 31, 2011 by SliverS2

[mad082]

ok. so it sounds like most of the issue is with the tyres. as people have said, get some stock rims (or 300zx rims as they are wider so you can fit wider tyres on them) and get some decent tyres for them. even have a look around for some used semi slicks.

[AngryRB]

ok. so it sounds like most of the issue is with the tyres. as people have said, get some stock rims (or 300zx rims as they are wider so you can fit wider tyres on them) and get some decent tyres for them. even have a look around for some used semi slicks.

by a decent tyre are we talking a soft jap tyre? what profile width do you reckon, as fat as possible???

[R31Nismoid]

I was doing 2.9 60fts with a 225/60/16

Just some shitty dunlop tyre, about $150 worth. So dropping back to 16s will help, but you clearly are lacking in practice at then moment as there is no way just going back to 16" rims/tyres is going to get you 0.5 of a sec

You need more practice, and whether you accept it or not - i tell you 100% right now you are down on power.

[AngryRB]

I was doing 2.9 60fts with a 225/60/16

Just some shitty dunlop tyre, about $150 worth. So dropping back to 16s will help, but you clearly are lacking in practice at then moment as there is no way just going back to 16" rims/tyres is going to get you 0.5 of a sec

You need more practice, and whether you accept it or not - i tell you 100% right now you are down on power.

ok well ill see if i can track some of those tyres down, will just have to see about the power side of it, though you may well be right, could do with a check on the dyno to see if the boost controller is getting the most out of the setup..

just dont wanna pay for a full tune again

[AngryRB]

Ive been trying to figure out what is the best way to set up the boost delivery on my AVCR

eg, should i set it to 1BAR accross all the revs or stage it like 7psi upto 4000rpm then 1bar to 7000rpm,

a small exhaust housing might get choked up fast with 1bar straight away or would it be the same?

[owen25det]

should just keep focused on one part of the track ie first half where the race is won an lost..

if your down on power you wont know untill your getting your first half of the track rite coz if your getting wheel spin in all of first, bit of second an chirping third

that will have an effect on your top end mph anyway..

once you master that part you will soon know if the car has power issues byy how the car is behaving at the top end..

first half of the track is all in your hands, where as the second half of the track 90% is down to the cars power..

couple of posts up someone commented on the smell of burning clutch..

perfect comment..

unless you have semi slicks an soft suspension, the launch is 80% in the left foot, clutch will start to smell but you have plenty of time between rounds

to let her cool

[Rekin]

couple of posts up someone commented on the smell of burning clutch..

perfect comment..

unless you have semi slicks an soft suspension, the launch is 80% in the left foot, clutch will start to smell but you have plenty of time between rounds

to let her cool

[koe]

Solid diff mounts and rear subframe bushings helped me alot to transfer the torque better.At least a engine torque damper which helps shifting.Diff gears is also a good thing to do.Some how higher gears are pref over lower gears.

My set up was MAZWORX cross member,Solid rear bushing on both subframe and diff,HKS Hype D rear coil overs,2 way lsd can't remeber my diff gears but sure it was higher then 411s,17 x 9.5 wraped in yokohama advans which I still use or nitto 100 threadware tires pressure set at 28 left and 25 at right.Depends on which way the car tends to jump at launch.No front sway bar and oem rear sway bar.But this is when you know about suspension travel.

I have never drag race a awd.I only do rwd.Not sure if deleting the front antiroll bar will help awd aplications....Never been a fan of drag racing.We go there to goof around.I just love to use the launch controller on my hks.lol.So much fun.

I had it set at 5k rpm.But this depends on how fast your turbo spools which has nothing to do with your thread..Ebake tech helps as well.

[zebra]

Perfect example of the wheel/tyre combo NOT to take to the strip