fc-racer

Went drag racing with my motorsport club. We had the track pretty much to ourselves. I had the EVC installed a few days ago, but the Andial microfueller was not installed at that time (due to a missing part). I could only run max. 1.0bar safely. I could hear no detonation so I think I should be ok.

My runs looked like this:
11:16am 13.097 @ 108.21mph - 1.0bar boost, full weight
11:49am 14.048 @ 105.94mph - 1.0bar boost, full weight, bogged launch, shifted into 4th
12:17pm 13.778 @ 106.54mph - 1.05bar boost, no jack/tire, launch from 6000rpm
12:22pm 13.295 @ 107.37mph - 1.05bar boost, no jack/tire, low rpm slip launch
12:50pm 13.454 @ 107.29mph - 1.05bar boost, no jack/tire, high rpm slip launch
1:00pm 13.210 @ 108.77mph - 1.05bar boost, no jack/tire, low rpm slip launch
1:24pm 13.630 @ 108.47moh - 1.05bar boost, no jack/tire, bogged launch
1:37pm 14.139 @ 104.45mph - 0.70bar boost, no jack/tire, low rpm slip launch
1:57pm 13.550 @ 109.67mph - 1.05bar boost, no jack/tire, high rpm slip launch

The boost controller added 4mph to my top end speed, that works out to roughly 40hp. The thing that bothers me though is that my stock boost run shows that the car is quite slow in stock format, only 104mph. I'm pretty sure that Porsche had specified over 106mph for a stock car. Maybe if I got it out of the hole better, I'd see the 106mph. My top end was improving towards the end as I got more used to the car, I almost hit 110mph on my last pass.

The boost pressure is what the EVC was set to, I believe that the pressure is actually about 0.1bar lower than what is set, the EVC is still learning how to give maximum set boost. It overshoots a bit, then overcorrects a bit, then stabilizes.

Fun day, too bad the car is so tough to get out of the hole.

fc-racer - who tried and tried and tried, but could not crack a 12.999 run

SonnyV

Great information. Thanks for posting it.

What do you recommend for a street launch without abusing the clutch?

Do you think with the fuel enrichment device installed you could break into the 12s? If so, what would be the launch rpm?

One more question, did you have a lot of wheels spin?

Thanks, <img src="graemlins/burnout.gif" border="0" alt="[burnout]" />

Sonny

fc-racer

Sonny, for a street launch, I'd say that a low rpm slip provides the most consistent low ET's. A high rpm slip has potential, but it's too variable to make good use of it.

The car felt a bit weak at the very top end so I think the fuel enrichment would help a bit. When I look at my quickest run, I notice that the 60' time is 2.008 which is actually quite good for a RWD car on 18" street tires. I should have given up right there and then A good 60' time for RWD on street tires is about 1.9 so if I could nail a good launch, it would have only barely cracked into the 12's. Being used to my racecar, it's quite a letdown to run a 13.0

If I had the Andial enrichment fully installed, I would have turned the boost up to 1.1bar or 1.2bar and run with more boost to get deep into the 12's. It was kind of nice to see that the car turns a 13.0 @ 108mph in complete street trim, 1.0bar boost and 94 octane Chevron, nothing special.

The launch surface of a drag track is extremely sticky. Your shoe gets stuck to the surface of the track if you walk on it. The morning run was the only one that I got just the right amount of wheelspin necessary to get into the boost range of the torque curve. After that run, the big cars lay down their rubber from the big slicks and you end up with either massive wheelhop or the car bogs. The 911 has a tremendous amount of traction so it usually bogs.

The car runs a lot better after the flogging it got today, seems like the previous owner never really opened it up

fc-racer

fc-racer

I just realized that I've drag raced every car I've owned, this might make an interesting comparison:

1992 Eagle Talon FWD Turbo - 13.8 @ 104mph
1992 Eagle Talon AWD Turbo - 12.7 @ 107mph
1989 Porsche 944 Turbo S - 13.8 @ 104mph
1991 Eagle Talon AWD Turbo - 12.0 @ 119mph
1991 Porsche 911 Turbo - 13.0 @ 108mph

I think I need to buy something newer than 1992

fc-racer

Patrik S

fc-racer!

Nice of you to post the results from your day at the strip When you have installed the Andial microfueller and draged it please get back to us with the results.

But how have you been driving up to now if your car only today runs better I was under the impression you usually opens it up

fc-racer wrote:
"The car runs a lot better after the flogging it got today, seems like the previous owner never really opened it up"


<img src="graemlins/burnout.gif" border="0" alt="[burnout]" /> Patrik

JamesE

I know what you mean about getting the launch right. I have been playing with my accelerometer doing 1/4 mile runs and it is a complete bitch to get off the line fast.

I thought i'd have another go this weekend. Fed in the clutch from about 5.5k and got it absolutely perfect. The car just rocketed off the line. What felt like a small about of wheel spin, and then just pure G. Unfortunately such was the force of the start that the accelerometer removed itself from its harness and ended up on the back seat

Of course I couldn’t repeat it and decided the clutch needed a rest.

What I find most difficult is feeling the bite point on the clutch, and the fact that it has a binary operation.

Oh well, it's fun to practice.

jeff91C2T

I only played once trying to get a good launch with my car. I had a G-tech Pro and was shooting for some 0-60 times (best was a 4.2). Car setup was 1/2 a tank of gas and one passenger. Track surface was sticky and the tires were 255 victoracers.

I've got headers which might make a difference on launching the car. For me, rev'd the car to 3500, slipped the clutch a bit until boost started to build, then release. If I went any higher there'd be to much wheel spin. Boost came on fairly quickly. Clutch would be fully engaged by a little less then a car length. Very cool seeing two big black marks all the way through first gear!

adrial

[quote]Originally posted by fc-racer:
<strong>I just realized that I've drag raced every car I've owned, this might make an interesting comparison:

1992 Eagle Talon FWD Turbo - 13.8 @ 104mph
1992 Eagle Talon AWD Turbo - 12.7 @ 107mph
1989 Porsche 944 Turbo S - 13.8 @ 104mph
1991 Eagle Talon AWD Turbo - 12.0 @ 119mph
1991 Porsche 911 Turbo - 13.0 @ 108mph

I think I need to buy something newer than 1992

fc-racer</strong><hr></blockquote>

I remember watching the video of your 951 doing the 1/4 before I had mine I think. That was ~1 year ago.

You seemed to take it pretty easy on the launch back then? I think your 951 could've managed better than a 13.8 @ 104..

Nice numbers and its always interesting to see just how much trap speed's can vary just by the launch. I g-teched my car 1/4 mile once...when it was running 18psi in 3rd thanks to the PO. I didn't launch at all...even waited a split second before I realized I was doing a 1/4 mile run...15.0 @ 107.5mph..Now the g-tech mph is higher than the track speed...but thats no launch...
I think my car would've done Quite well at the 1/4 if I had launched it. No clutch abuse for me though. The worst I do is a 3k rpm clutch slip start for autocrosses.


<img src="graemlins/bigok.gif" border="0" alt="[thumbsup]" />

fc-racer

Adrial,

Taking a car to the 1/4 mile is a totally different experience than running it hard on the street. On the street, you can take off at your leisure, on the track, you are trying to cut a good reaction time. Even if you take your time leaving the line, you will still be rushed because you don't want to be inconsiderate to the other participants.

Also, the launch surface of a 1/4 mile track is amazingly sticky. Your shoe comes off your foot when you step on the launch surface, I'm not lying.

When you launch a 944 Turbo on the street with 17" tires, you really can't do too much; you either get wheelhop or the car bogs. I launched it from 6000rpm at the track and it hopped so bad I thought something was going to break. The only way to reduce that time would be to spend the time to do another 10-15 runs to try and nail it perfect. I think the best I could have done that day would be a 13.5, not much more.

Also, the MPH is generally pretty consistent, regardless of launch. MPH tells you how good the car is, ET tells you how good the driver is. When you have a slow ET like 15.0 seconds, you have so much more time on the track to accelerate that your MPH will be higher than if you were to get a lower ET.

When I get the RS 3.8 clutch put in, I'm going back to break into the 12's with the 911, then it retires from being a drag race car. I then put my efforts back into my racecar and getting that into the 11's. Once it's in the 11's, I want to build a monster motor for next year's Knox Mountain Hillclimb. Now that I have the class record, I want to defend it and I think 500hp will make that an easier task

fc-racer

fc-racer

Found a cool tool to calculate 0-60 times using drag race runs. <a href="http://www.teamnabr.com/index2.html" target="_blank">http://www.teamnabr.com/index2.html</a>

I pumped through all the cars I've taken to the track through the algorithm, which seems to be pretty accurate when I put in the figures I got at stock boost. The 911 does quite well with just a boost controller:

Talon AWD - 12.0 @ 119mph
60ft: 1.760
330: 5.149
1/8: 7.185
mph: 92.86
1000: 10.102
1/4: 12.011
mph: 118.49
0-60: 3.25 seconds!

944 Turbo S - 13.8 @ 104mph
60ft: 2.331
330: 6.035
1/8: 9.077
mph: 81.27
1000: 11.636
1/4: 13.811
mph: 104.20
0-60: 4.90 seconds

911 Turbo - 13.0 @ 108mph
60ft: 2.091
330: 5.621
1/8: 8.536
mph: 84.38
1000: 11.008
1/4: 13.097
mph: 108.21
0-60: 4.32 seconds

IanM

Hey fc...
Yes, I'm still in Argentina. Well, back in Argentina is more like it. I came back to Vancouver for a few days then went to Montreal to see the Grand Prix. What an awesome week that was!! Anyways, I was wondering, did Darren have the Supra on the dragstrip? What sort of times/speeds does that thing post in the 1/4?

biiig-hp

[quote]Originally posted by fc-racer:
<strong>Adrial,


Also, the launch surface of a 1/4 mile track is amazingly sticky. Your shoe comes off your foot when you step on the launch surface, I'm not lying.

Also, the MPH is generally pretty consistent, regardless of launch. MPH tells you how good the car is, ET tells you how good the driver is. When you have a slow ET like 15.0 seconds, you have so much more time on the track to accelerate that your MPH will be higher than if you were to get a lower ET.

fc-racer</strong><hr></blockquote>

If your in BC, you must be running at Mission. Great place to run. Super sticky track with altitude often bellow sea level. Your shoes will come off your foot at this track


I agree. you can leave the hole at an idle and still run the same mph. as you would droping the hammer at 6000 rpm. Give or take 1 mph.

Francisco Martinez

Drag is not my thing, but I have amassed many speeding tickets so I have to start taking my racing elsewhere and Trackdays are scarce in Puerto Rico. So anyways, for those that do know about drag, here are my results for my turbo 3.6 whose only mod is a cat by-pass and smog delete:

First pass -> 1/4 mile 14.170 @ 106.34 mph (Wheel hoping thru 1st gear, had to change to 2nd gear way before redline and wait for boost to build up again)
Second pass -> 1/4 mile 14.039 @ 107.51 mph (Just rolled out on 1st gear and then WOT.

Only did two passes, because the wheel hooping was not doing the car any good. I not sure if this is good, decent, or bad. I know these cars are supposed to be in the 13s but I don't want to imagine how the magazines launch these cars.

pcar964

Stock 964 Turbos ran the quarter in 12.8. You guys are way off.