New best 1/4 mile time

[Darren5.0L]

Set a new personal best for the car, however a slight mechanical, issue made itself known and has limited the potential of the car, more on that later, here's the numbers.

This is my first run of the evening: (ACE lane)


You may notice that after the 1000' mark my car and the 2005 V6 Mustang both gained approx 20 MPH, as anyone can guess, that's a little odd.
My cars' rate of acceleration dropped off.

Then the second (and last) run of the night, same lane, decent launch and tire traction but look at the times. FYI I still beat the short box HEMI pickup beside me...



Here's the reason what all this went down...


The 180,000 km factory stocker didn't take the 400 BHP and 400 BTQ so well, it simply fried the whole way down the track until 4th gear.

The clutch has been slipping for about 2 seasons now so this is not unexpected, however I had hoped to make it the rest of the season on it.

Regardless, I have my brand new SPEC stage 3 ceramic setting here waiting for the old one to give up.

I should have it back together around Wednesday depending on how quickly I can get the flywheel machined.

All in good fun and I was still able to drive the car home from the track.

BTW I did that one with the 75 HP jets, I forgot to bring the 100's with me to the track. With the new clutch, the 100 shot and non-street tires I should be well into the 12's.

[shakes]

very nice... time to update the time slip database

[Darren5.0L]

Well, it's not near as fast as the car can could go, and I hope have a better time by next friday, but sure, why not?

[red82gt]

You'll find it nearly a constant for a car to gain approximately 20mph from the 1/8 to the 1/4. It takes a lot less power to accelerate from 68 to 88 mph than it does to go from 86mph to 107mph. It also took the V6 car 5.7 seconds to gain that 20mph-it took your car 4.7 seconds to gain 20mph starting at 20mph faster than him.

Even 10 second cars that trap 125 will trap 102-103 in the 1/8th which is near the 20mph again

[Darren5.0L]

That may be true, but on previous runs I have made I usually pick up a gain of approx 25 MPH, and that was before Heads and Intake. Further to that, my overall trap speed stayed equal to what it was before I did my H/I. I've pulled consistant 107-108 MPH traps running the stock engine.

[The Fox Master]

Originally Posted by Darren5.0L

That may be true, but on previous runs I have made I usually pick up a gain of approx 25 MPH, and that was before Heads and Intake. Further to that, my overall trap speed stayed equal to what it was before I did my H/I. I've pulled consistant 107-108 MPH traps running the stock engine.

I'm calling BS on 107 mph stock mph unless you gutted that car to the bare sheet metal for those runs - What's your car weigh? Was that with your G-Tech or something?

[The Fox Master]

Originally Posted by red82gt

You'll find it nearly a constant for a car to gain approximately 20mph from the 1/8 to the 1/4. It takes a lot less power to accelerate from 68 to 88 mph than it does to go from 86mph to 107mph. It also took the V6 car 5.7 seconds to gain that 20mph-it took your car 4.7 seconds to gain 20mph starting at 20mph faster than him.

Even 10 second cars that trap 125 will trap 102-103 in the 1/8th which is near the 20mph again

Interesting - I trap 23mph faster on average. 89 in the 1/8, 112 in the 1/4.

[Darren5.0L]

Originally Posted by The Fox Master

I'm calling BS on 107 mph stock mph unless you gutted that car to the bare sheet metal for those runs - What's your car weigh? Was that with your G-Tech or something?

perhaps I'll state it again,

Originally Posted by Darren5.0L

I've pulled consistant 107-108 MPH traps running the stock engine.

ie stock longblock, stock engine components, E7TE heads, HO intake and stock F4ZE-DA camshaft, stock throttle body.

stock engine is a far different statement from stock car...

Making no mentions of induction, gearing etc because they are not relevent to the comparison of before and after a heads and intake install.

Here's a timeslip from a 107 and change MPH trap from last season, the 108.XX MPH is awol but close enough for discussion sake.

[The Fox Master]

So you mean those pre-head/intake times are also using nitrous yes?

[Darren5.0L]

precisely

[The Fox Master]

Originally Posted by Darren5.0L

precisely

Well that changes everything

[red82gt]

Originally Posted by The Fox Master

Interesting - I trap 23mph faster on average. 89 in the 1/8, 112 in the 1/4.

Bolt on slicks and it'll probably be 21 or 22. If your picking up 25mph on the top end it is usually because you were spinning somewhere in the first 1/8th mile. Judging by that second timeslip that Darren posted, it wasn't the cleanest 1/8th mile.
For example, my car used to be constantly from 84-86 in the 1/8th and 105-107 in the 1/4 so again, low 20's. I was just trying to illustrate that just because the v6 car picked up 20mph in the second half and his car only picked up 20mph is not out of line.
Turbo supras can sometimes pick up 35+ in the second half but they are the stupid-looking ones that run 13's at 120's.

[The Fox Master]

Interesting theory. I dont get much if any wheel spin launching off idle and short shifting 2nd when racing on regular radials.

Running drag radials now, my only clean pass so far is right in line with my best street tire times (lots of VHT prep that night) and belive me these things dont spin at all even slamming 2nd gear.

It would be interesting to try a slick where I can really launch at a high rpm but that being the case I wold thing MPH would increase if anything.

20mph seems to be a good estimate, but nothing is set in stone as surly HP and gear ratio must have some say in the spread of MPH between the 1/8th mile clock and the 1320.

[red82gt]

Fox Master,
Nothing's set in stone and it is more like 20-25 realistically and it's also out the window somewhere in the 8 second range (once cars are overpowering the track) as well but if your gaining 26+mph on the top half-especially in a low-powered street car, chances are your first half wasn't very clean-or your gearing is way off. For him to expect to gain at least 26mph as he was before is maybe not realistic.
The car should be running faster than it is but I think it'll pick up a mph or so in the 1/8th and probably 2.5 up top with a better clutch and more seat time with the new parts-and the times should plummet-it's got 12 second trap speeds easily already.
With your car compared to his earlier timeslip, you are 8mph ahead at the 1/8mile, but you are only 4mph ahead at the end. As you said, your car isn't slipping or spinning excessively-so which car do you think is getting down the track better?

[Orange302]

just to throw time in there. The 1/8th mile should be almost exactly .65 of the quarter mile.

so as darren as an example. 13.192x.65= 9.0428

He did about a tenth slower than that. So maybe he did slip alittle in the first 1/8. But it is pretty close.