Dragstrip Advice

[B17Crew]

Greetings Everyone,

This is my first post to this site, I have followed the postings here regularly and decided it was time to jump on in.

I have a Polo Green/Beige LT4 coupe that I bought used with 15,000 miles in ‘98, I currently have 41,000 miles on it. Only mod is a K&N air filter, other than that, it’s completely stock. It is the most reliable car I have ever owned, and it’s my daily driver.

I noticed posts that have mentioned 0-60 as well 1/4 mile times for the LT4. From what I have read, most of you that have unmodified cars seem to be in the low 13’s with trap speeds above 106 mph.

Made a few runs at the local strip and my two best runs were...

1st run 13.8@105 mph
60’: 2.281
Reaction time: 1.069 (I know I have to work my RT)
this was with a FULL tank of gas, 30 psi in the Eagle GS-C’s launched at 2,000 rpm temperature was 69 degrees. I think the track is about 800-900 ft above sea level

2nd run (different day, same track) 13.7@104 mph
60’: 2.293
Reaction time: 1.178
this was with a HALF tank of gas, 30 psi in the Eagle GS-C’s launched at 1,500 rpm temperature was 59 degrees

I know I have to experiment with launch/RT, my concern is the numbers that I have run are similar to Car and Driver and Road & Track tests that have been mentioned in recent posts. I had a ‘94 LT1 six-speed and ran 13.6 @103.63, mods were a K&N and air foil.

Can anybody with a car similar to mine (mod wise) let me know what RPMs you are launching at, are you dropping the clutch, etc.? I had tried 2,500 rpm down to 2,000 and I get a lot of wheel spin. This produced times in the 14’s!

Any advice would really appreciated.

 

[Mad-Mic]

looks like your bogging the motor with a 2.29 60' try leaving above 3000 rpm that car should run around 13 flat easily it just takes track time you should be around 2.0 to 1.9 on your 60' times

 

[Vettelt193]

First off, i am not sure how much the high level will reduce your speed....

second, the way to get really fast times is not to dump the clutch, but to feather it.... what your goal in 1st gear really is: keep the RPM's up in the power range, and ease the clutch out (basically backwards driving, instead of driving with the gas pedal by pushing it in, you are slowly letting the clutch out).... the problem with this style of driving is you go through clutches... the benefit is your car will go really fast if you learn to do it right!

 

[B17Crew]

Thanks Mad-Mic and Vettelt193, I am going to expirment with my launch technique, I need to get out to the track to practice. The car has always pulled strong as the revs go up. Once I have the new runs under my belt, I’ll post the results.

Save the Wave!

 

[twiget]

Welcome to the CACC B17Crew.

It looks like Vettelt193 and Mad-Mic are steering you in the right direction.

If you've got any more Corvette questions, this is the place to ask.

Jason

 

[okie]

Sound like you are about where most everyone else is. I am still too afraid of breaking mine to do anything yet. Give me a few weeks, I just got it. By the way, "B17", you can't be that old, can you? If so, I have always had the upmost respect for that aircraft, got pictures all over the place from some old sites in England.....

 

[lt4 gs]

an RT simulator is also a big big help.......finding one is the trick.......if we could just get uniformity with a traffic light..........I personally could be a killer on the strip...........problem with the test and tune or qualifing runs is they aren't repeated over and over and over............like to the tune of the 44 years ........looking at traffic signals

 

[cntrhub]

I'd concentrate on the R/T. I don't think you have a problem with the driving, shifting or getting the clutch hooked up. The car sounds like it runs very good. You need to clear your head, once you trip the 2nd yellow light. Time goes fast on the line, and the guy working the tree wants you out of there, and out of there fast. He/She is going to punch the light off before you can gather a thought. That's why you need to "condition" yourself. So, what you need to do, (as I do) is sit near the tree and watch the ideosyncrasy of the tree's lights. Study the tree's pattern. Use your feet watching the yellow hit green. Leave before the green light comes on. Do a lot of "air guitar" with your feet. You may look like a little strange doing this, but it should bring down your R/T.
Never break concentration once you are at the line. When you see drivers sitting there and the green light is on, they broke concentration. They leave way too late. I bet you can look back at your runs, and think you could have left earlier then you did. Believe me, you have a very large time gap to narrow between the yellow light going off, and the green light coming on.
Red light a few times.....this will help you remember what you shouldn't do.

 

[B17Crew]

I’d like to thank EVERYONE for their advice.

The 1996 LT4 Forum is a site I frequent, figured I was here often enough I should join in, the information has been invaluable.

cntrhub, I never thought to practice just by watching the idiosyncrasy of the lights and “air guitaring it with my feet”, that is definitely worth trying. On all my runs, I had left when the light was green, sounds like I need to launch as the last yellow lights up.

okie, congrats on your Torch Red LT4, you’ll love it! You hit the nail right on the head..."B17" does apply to Boeings B-17 Flying Fortress. I’m not old enough to have crewed one, but I have a deep respect for the aircraft and the crews that manned them. (I have a freelance design business that centers it’s identity around the WWII heavy bomber) I had a field day with Boeings lawyers when I contacted their trademark and licensing dept!

lt4 gs, check your 6 when your practicing at those lights. The local gendarmes pop up when you least expect it.

twiget, glad to be aboard!

 

[cntrhub]

Visually slow down time

"....sounds like I need to launch as the last yellow lights up." Do that, and for sure you'll red light every run. Expand your conception of time. Remember to move your feet, "when the yellow goes out!" You want to, "time" as close in hundreds of seconds, when you think the filament in the green bulb, just begins to glow. That's how to.... "Cut A Light."

 

[B17Crew]

cntrhub,
Thanks for setting me straight on the yellow, your advice has put a whole new perspective on this for me. This is going to take some practice, getting a perfect launch is appearing to be an art. I can’t wait to get back to the track!

 

[Mad-Mic]

cnt i hate to say it but you got it a bit wrong. on a .500 bracket tree you leave right before the last yellow comes on not when going out waiting on the green if this is the case you already lost. i cut .520 to .550's all the time no prob and my 60' times are around 2.05 all cars have what we call "roll out" this is the time that the car reacts to your reaction. there are 2 reactions taking place.

1. you reacting to the light = .050

2. your car reacting to you = roll out .500 or so

so in theory and track proven if you leave when the last yellow is britely lit your already late by .100 or more and at bracket racing you win it or lose it on the starting line not at the finish. i launch as soon as i see the 2nd yellow go out and know the last yellow is about to be dimly lit.

there are 3 "britenesses" to a light.

1. dimly lit (just lighting up)
2. brite (full color)
3. dimly lit or going out (dimming out)

most of the time unless you got one bad a$$ ride (with 1.20 60's) if it's full color your late cause your roll out. roll out can be adjust thru your suspension and power but you can't adjust the driver.


here is a pro .400 reaction timer you can play with that the pro's use. i got a box that i use and practice with that you can set dial ins and roll outs similar to what your car runs.

Click Here just pretend that all 3 ambers are the last yellow you sorta gotta guess it but gives a good ideal that you got to leave before the ambers come on

 

[Ken]

Whit Bazemore game

:cool

_ken

 

[cntrhub]

the 'ol crawl before you walk syndrome

Mad, I hear ya. But Crew is a little green under the collar. Lets get him rolling one step at a time. I did mention to have him expand his concept of "time." If Crew gets enough practice to.. "the art of the leave".... he might figure out to move sooner on a yellow, than seeing "red" on every pass. I'm just too conservative in my approach of teaching I guess?

 

[Mad-Mic]

hehe no prob cnt. just trying to help

 

[Mad-Mic]

heres some other posts i've come across with good info about dragracing our vettes

Automatic Tricks and Good Stuff!
Track Tips!

Great tire tips!
BFG Comp T/A Drag Radials????

Good Stuff about LT4 cars and launches!
Going to the track sunday

lots of good info in there on launching your vette! some of it is automatic stuff but still alot of good reading. i suggest taking a look at what i've written about and what others have written about and it will help you alot when it comes to dragracing your vette

 

[sothpaw]

launching

B17, (nice name, my Uncle flew 27 missions)

1. I like 2000 rpm for launch. Don't dump the clutch, let it out slow like vettelt193 says.
2. Important--I am still having this problem--get the water off the GSCs. The strip I usually go to put water down for you to do a burn out. I don't do burnouts--but if your tires get wet going though that stuff, you need to do a small one to clean them.
3. I have gotten several 2.1 sec 60 foot times with GSCs and full tank of gas. Try 25 psi in the tires, 30 is too high.

A good launch makes all the difference. My car just won't run quite right if I bog it or it loses traction.

Reaction time is another issue. Attack that separately. Don't try fixing everything at once. BTW, everybody has different reflexes. It doesn't matter at a light--all that matters is consistency, you can correct for reflexes. I start when I see the second yellow and I get .5-.7
reaction times consistently.

 

[Ken]

Michael, it's certainly nice to see that someone actually uses the "Search" feature. Well done!

_ken

 

[Mad-Mic]

actually ken tell you the truth i've been meaning to put this together for you guys. it's posts that i've ran across regarding drag racing vettes on this site. i just went thru all my other posts and had to refind them! took about an hour of bug-eyed searching :L

 

[vetteguy]

Mad-Mic, thanks for the info. Very informative. Guy