1/8 mile data, can it be right?

[PT-Dave]

OK, here are the basics:

Date: Today, May 21, 2003
Temp: 67 degrees
Hum: 83%
Dew Point: 61 degrees
Alt: 648 FT.
Surface: concrete (level)
Wind: 6 MPH, from the side
Location: Dallas, TX

Boost setting: 13 (using Hallman ES)
Custom Cowl cold air system
3" hi-flo cat, 3" exhaust, 3" glasspack, no muffler
Auto-Stick tranny, in drive, traction control on
Stock 17" tires & rims, no rear seats
Weight: approx 3340 lbs incl. me (1/2 tank gas)

Device used for measurements: Tazzo VPC (Veh perf computer)

Results:
60-ft: 2.29 sec
1/8 ET: 8.88 sec
1/8 MPH: 86.8

I did this, but am having a bit of trouble believing what the meter says. Unfortunately, I was not watching the speedometer, but was montoring the boost & A/F gauges to be sure I didn't have anything out of range. The run really felt super strong, but I sure wish I had noticed the speedo, so I could better confirm the accuracy of the meter.

Based on the time it produced, it calculates (roughly) to a 1/4 ET of 14.05 seconds at nearly 98 MPH! I'm skeptical, but hopeful. I plan to go out Friday night to a real strip (1/8) for confirmation.

Anyone had any 1/8 or 1/4 mile times to compare to this? Comments?

[COP TZER]

a 14.05 ET 1/4 would be a pretty sweet time man!!! And that's with basic mods too[?]...full exhaust, intake, and MBC. You should try upping the boost a little. Was that with the spare tire out?? If not that could shave some time too, every little bit helps.

[Ian-PT-GT]

Pt- dave,

In my first stock passes I had 10.1 at 68.4 MPH at the 1/8 and ended at 15.921 at the 1/4 at 84.59 with a 2.28 at the 60 feet.

With the air intake silencers removed I improved the times to 9.35 at the 1/8 at 70.1 and 15.74 with 89 MPH at the 1/4 with a 2.23 at the 60 feet.

with 14 PSI and the torque converter (Auto stick model) slipping and a child seat installed, I managed a 9.05 at the 1/8 at 72.2 MPH and a 15.45 at the 1/4 with a speed of 90 MPH.

What I noticed just a 20 MPH or less increase at the second half of the track.

My best time was 15.2 but don't have the time slip with me to give you the specifics.

Ian

[Mike Radowski]

Now, pull out the back seats, the spare, the child seat and you will probably be in the high 14's. Not to bad for a family car, huh.

Mike

[old head from phila.]

When I ran 3 weeks ago I turned 15.33/91.50 in 1/4,9.81/71.07 in 1/8,with 2.60 in 60 ft.Using drive,no power braking,with >025 hole in the orange hose,traction control on.13# of boost droping to 9#.Any one running any where in the 14s,even 14.9 is doing good with a autostick Old Head

[old head from phila.]

IAN-PT;You said you picked up .2 et. and over 4 mph.taking out the silencers,is that the 2 in the air box or the 1 in the tube.Let me tell you guys that are out there testing.WEATHER MEANS SO MUCH,here in Phila. you can see a difference of 3 1/2 10s and 4 mph.I have been racing since the 1950s and when igo to the track,i do weather corections every run,some times the times go up then down then up again,the other night for the first time i saw it stay the same for 6 hrs.Lots of other racers check with me at the track.the best way of testing is A,B,A,b in less then 1 hour,THIS IS THE ONLY WAY TO TEST WITH OUT WEATHER CORECTION. Old Head

[PT-Dave]

First, let me state that the Tazzo VPC is VASTLY overrated. It is not consistent enough to be even considered a valuable tool for tuning. Too bad it took a couple of hundred of my hard earned dollars to find that out!

For example, one run it reported that I had run a 8.79 Sec. @ 83.6 MPH, when in reality, is was a 9.76 @ 70.97. Another run: Tazzo - 9.26 @ 79.68, reality - 9.679 @ 72.35. It did have a few that were within .1 to .2 seconds and 1 to 3 MPH of the actual run, but it was not consistent with regards to the actual run. Sometimes it would say I was slower than I really was, other times, quicker than reality. All in all, I call it a piece of junk!

Here are the averages for the night indicated showing the differences in temp and configuration of the setup on my cruiser.

Date Temp Reaction 60-foot ET MPH Comments
8/23/02 96 0.595 2.403 10.281 68.350 Car completely stock, no nothing!
Best-> 0.606 2.372 10.164 67.99

9/24/02 92 0.589 2.210 9.652 71.377 Gained about .6 sec & 3 MPH
Best-> 0.487 2.164 9.525 72.01 w/custom exhaust & intake

9/30/02 95 0.858 2.238 9.777 71.051 Actually a little worse than last wk
Best-> 0.730 2.209 9.708 71.26 It was hotter than last wk too.

10/29/02 88 0.672 2.255 9.792 71.487 About the same as last wk, a bit slower
Best-> 0.680 2.213 9.694 71.77 ET, but quicker trap speed

Boost controller added early May 2003: Hallman ES
5/23/03 84 0.674 2.258 9.760 71.541 Minimal gain w/use of boost controller
Best-> 0.766 2.249 9.607 72.67 set @ 13~14 max, dropping to 9

The boost controller set @ 13~14 pounds caused several poor starts due to excessive wheel hop. What was lost on the line was made up for on the top end. Still, my best was only 9.607 @ 72.67 MPH. On the night of 9/24, I got a best of 9.525 @ 72.01 MPH without the boost controller. I'm not really convinced that the boost controller is helping that much, since the wastegate still opens after the initial boost is reached allowing the boost to fall by as much as five pounds. I guess I will have to try to up the spring pressure ala Exhaust Depot's suggestion.

I did have some nice kills though, in spite of the fact that I wasn't doing as well as I had hoped I would. I don't have many particulars about the cars I ran, except that several should have been able to whip me. For example,

1969 Challenger 440 Auto !!!!
1976 Monte Carlo, big block, w/slicks
Mazda RX7, 2 of them
Honda, anything, except the S2000 (he got me by about .5 sec), I outran them all! Ha! Ha!
60 Something Chevy stepside PU, big block, slicks, very loud, very slow!
Olds? Aurora, with Northstar 32-valve V8, three times, three wins!
Mustang 5.0, twice!

All in all, I made 18 runs, winning 14 of them! So, like I said, it was still a good night!

Lets hear from some of the rest of you guys. How much has the boost controller helped you at the strip?

[old head from phila.]

Dave:looks like you had fun.Your car seems a little faster then mine.I would like to give you weather corection info. if you call me,it will cost you about $70 from jed's for the equip.then,and only then will you know what you are realy turning.Is your's an autostick,what were your shift rpm?I do wish you were runing the 1/4 mile.Old Head

[PT-Dave]

Old Head,

Can you describe what you mean by weather correction? I, as have others, noticed that as the air cools in the late evening, the cruiser gains some speed. I'm sure that burning up some gas saves some in the weight department too, helping everything as well. The biggest gains in speed that I have noted come when the engine is allowed to cool down a lot before making a run. My best run came after a 75 minute cool down, then whammo, I broke out with a 9.52! That was before I added the boost controller.

Mine is the auto-stick, and I was letting it do the shifting for me, so I guess about redline was when it was shifting. I wasn't watching the tach, but the boost & a/f gauges to be sure I hadn't set the boost too high. Don't want to blow the engine!

I will get a chance to run the 1/4 mile in July at Hallsville Raceway when we have a big PT event scheduled. Maybe I can get the boost falloff figured out by then.

[old head from phila.]

PT_DAVE:Call me,I will send you the info. You won't belive,you will start turning the same times weeks apart.You will see that you have wasted your time with out weather corection.there is a nother very important thing,staging i have thousands of 1/4 mile runs under my belt,and i am a poor stager,but better then most.Some nights i get good can can run almost the same times with corection,thats the only time i can tune.I might want to mention i have a VERICOM computor that reads 1/4m,1/8m,1/16m,60ft,30ft,15ft,2ft.et.,mph.G force,and i run with it every run,boy is it good,i watch it more then the track times because you can't cheat it by different staging. OLd Head