Quarter mile times

[sakimano]

Great question

[sweegie]

Interesting. Why has no one mooted drag strips as a benchmarking method for car performance?

Maybe because some folk prefer midrange acceleration to playing top trumps like a schoolboy?

[Shoppinit]

So you're saying a rolling road would be better?

[sweegie]

I prefer a good datalogger and the A9

[bam_bam]

I have always wondered what a same-for-same comparison between; a good quarter mile stg2 tune/modded car and a fast road stg2 tune/modded car... around the same track... would produce.

For example.
2 x B7s, one with;
A top spec JHM charger and tune (known to put down good quarters etc)
vs.
A whatever spec charger and MRC tune that has great low and mid-range but not necessarily a stellar quarter mile or headline HP.

Same track, same driver, same suspension, same brakes etc - just different headline figures and power delivery.

[sakimano]

I have always wondered what a same-for-same comparison between; a good quarter mile stg2 tune/modded car and a fast road stg2 tune/modded car... around the same track... would produce.

For example.
2 x B7s, one with;
A top spec JHM charger and tune (known to put down good quarters etc)
vs.
A whatever spec charger and MRC tune that has great low and mid-range but not necessarily a stellar quarter mile or headline HP.

Same track, same driver, same suspension, same brakes etc - just different headline figures and power delivery.

That would be cool.

The new kits are all very similar, acceleration wise in a straight line. JHM stage 2, TTS-MRC, Apr TVS1740...there's very little between them. I imagine they would be very similar in lap times. The jhm and tts thrive from 5k-8k. The Apr has an advantage down low... But you don't spend much time down at 2000-4000 rpm at a track when you're trying to set a lap time.

So reality is they're all going to be pretty similar. Driving dynamics on all 3 kits are good . IE they don't do great in a single gear pull then suck <beep> when you change gears...like some of the other offerings from VF, PES and the original launch of the APR TVS1320 kit before they asked JHM to remap it for them.

All 3 kits are running low 11s@125 or so on pump gas with street tires and full interior.

In November JHM is hosting a 1/4 mile day in California. Hopefully all their competitors send a car to compete. JHM may have one of their first built motors available as well as stage 1 and 2. As for a track day with one driver it would be tough to make it fair as finding 3 supercharged cars with the same wheels/tires/suspension/mounts might be tough. Most guys with a big blower have done everything else too.

[rickster147]

I'll put the slips on soon it was a hot day and there was a strong head wind also there was no wheel spin or bogging down you got to remember cars set up to 486 ps due to low boost cause one of actuators isn't working properly on one of turbos and tc slipping this how MRC mapped it to be safe

[IanH755]

Today looks like the last chance for a dry day at Santa Pod this summer so I'm off to give it a shot and I'll post up my slips later today!

[rickster147]

Nice 1 Ian will await the results

[IanH755]

As expected 1 sec slow and 5-7 mph slower too. Will do a few concrete runs tonight and see the difference. Bogging off the line massively and then 1st-2nd wheel spin. All in manual with esp off.

***edit***

Done 1 more run and did 13.4 @ 104. It looks like I owe Saki an apology too as I'm still bogging down at the line rather than wheelspinning like I said in earlier posts!

[bam_bam]

Don't apologise, he won't be used to it and he'll have a stroke... not the good kind.

[IanH755]

Here you go - Overall average of 13.5 at 105mph the same as Rickster. I did the first 3 runs back to back and started to get a lot of heat soak by run 3 so I had about a 1 hour break before the 4th run and then a drag bike grenaded it's engine all across the track (got the video too) so I called it quits, it wasn't like I was going to get any faster.



When I got home I did another 4 runs on concrete (3 back to back and 1 about 20mins after) and averaged 12.6 at 112mph without the same "bogging down off the line" feeling that I got at Santa Pod. If you could get a 5k-6k rpm launch it would fly down the track but the box would be a tattered ruin afterwards

PS. I know my RaceChrono setup isn't as accurate as the Santa Pod setup but it's the same 10hz as the VBox so I'd expect maybe 0.1-0.2 secs difference over proper timing gear costing £10K+ (proved by 5th gear). The times and speeds are all fairly consistent too.

[sakimano]

Did you run that device while at the strip? Would have been a good way to 'calibrate' it and see how accurate it really is.

[IanH755]

Like a dumbass I'd left it and the rest of my in-car recording gear behind in the rush to get out of the house after I over-slept

However, there's another in mid September that, depending on the weather, I might go to and I'll be putting my stuff in the car the night before this time!

[sakimano]

I have brought my pbox to the strip and forgotten to run it half a dozen times. Now it's my gopro that I bring and forget to turn off between bunches of runs ... Killing the battery and filling up the card in the first hour of a 5 hr test and tune/rwyb day.