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Discussion Starter #1
Im wondering if anyone else out there can tell me what my car should be doing in a 1/4 mile. I had a 2005 AUTOMATIC with long tubes Vararam and a great dyno tune and a set of perelli corsa . I could go to the drag strip here in Florida get to the start line put the car in d hit the gas and run 12.4 and 117mph all day long. Getting board I start going to sebring raceway and running the 3.7 mile road course. Well with the automatic it really struggled in the conners and I was told if Im going to be serios about running road courses my automatic has to go and a 6 speed is in order. Well thats what I do I get an 05 precision red vette with Z51 package and 342 rear gears 6 spd manual. I put some flowmasters on the vararam and my favorite dyno guys tune. Now I have yet to put the long tubes on and I bought a set of 4:10 rear gears for a little more umpf at sebring. My dyno guy says I sould go to the drag strip and see what my car can do now before he does the long tubes and the gears. Good idea I head out last night to the drags. Now im thinking just like you follks on the forum that with a 6 speed manual, 342 gears and a dyno I should be running 12.6 12.7 easy. My dyno numbers are 371 hp to the rear wheels so Im figuring get this bad boy to hook uip and watch out. Well now comes my dissap[ointment. my 1st run was 13.5 at 107 okay launch was hard a little slipage and spinning tires but 13,5???? next run I try to leave littel more hole shot still hitting 13.5 make a long story short my best was 13.5 at 109 a huge cry from my 12.4 117. Does anyone else out ther have a similar car as mine and what are they running for times. Im so upset I wanna sell the car and foget about wasting the money for installing the long tubes and gears. at 13.5 IM a long way of from 12.4 I was thinking i was going to be high 11s and now this. Any feedback willl be so much appreciated as I really can bel;ive I could not break 12s Again if im going to run road courses then I guess the 6spd the way but im so mad at 13.5 I feell like giving up
Feedback please sorry for thre long post
Jim
 

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What kind of tires are you run'n? what rpm's are you shifting at? How much practice have you had launching a manual? How are your shifting techniques?
 

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ouch sorry to hear that, i like C6vette's questions. Do you have a trust worthy buddy that could maybe make the pass? or someone that could ride with you?
 

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do you have a vid of the runs? Is this your first time driving or racing a manual transimision car? WAY too many variables left in the open. Like the others said, if experience is an issue have some one else take it for a spin, or ride with you or take a vid and post it and then we can get a better picture of what may be going on and be able to lend a helping hand.
 

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Discussion Starter #5
Dissapointed

I have a ton of road course experience and a fair amount of drag experience with automatics, The last time a ran 1/4 miles with a stick was 1986 in my GT mustang with 390 gears and 5 spd It ran 14.8 nothing like the vette I admit I felt very aquward launching the vette the other night. It seemed like I bogged the car 1st run I just waited for green and kind of clutched my way out I ran a 13.6 Buy the way Im running Perelli corsa that when there hot stick like glue. My automatic I could go in the box get the tires good and hot then roll up to the line punch it and it hooked up perfect no spin great launch unlike my Nittos that would break loose. The next run I sat at the light reved the cat to a steady 4000rpm and whenit turned green I just dumped the clutch and the car just kin=nda bogged and then took off real har still 13.5. 3rd time I went up let the lights start to run and I floored the car an dummped the clutch. This time I dont know what happend I either broke the tires completlyt loose as the car just skinda sat the not moving much I banged into second and same thing car still didnt really move much felt like either the tires were completely broken loose and I spun all 1st and 2nd or (I don't know if this was possible) the clutch just didnt grabbed at all and slipped the whole time which is kina like it felt as a matter at the end of the run I pulled ofer and spun my tires because I thought I blew the clutch. So I guess where Im disapointed is I feel like my car has somthing mechanically wrong with it because it ran so slow but it runs perfect and it dynoed really great as well. So if im hearing everyone correctly that launch at the begining is that costly is you screw it up and being off 1 second is normal

Jim
 

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post up a slip with 60', 1/8, 1/4 mile. What was your launch rpm? What were the weather and track prep like? What were other vettes running that day?

You're down a lot including MPH. Could be bad driving with a poor launch (wheel spin, and low rpm bog), slow shifts, and not shifting at redline in each gear; or it could be bad DA and prep at the track, or it could be your car isn't running well, or even a combo of factors. Driving factors can be measured by logging your runs next time you go and verifying your shift rpm and measuring the time it takes to shift. Alternatively, go with a buddy that is a proven M6 track driver and see what he does in your car.

Going from an auto to manual kills most people's drag racing times. With more power and less weight in my M6 vette, I was slower ET wise than when I had my Camaro with an automatic.

If you think it isn't the driver or weather related, then I'd look at your clutch and put the car on the dyno and make sure you're not down on power.
 

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My car ran a 12.5 @ 117.5mph the very first time I ever drag raced in my life. This was with Michelin PS2 tires, long tube headers, intake and a tune, dynoing 395whp or so on a Dynomite dyno. I think my 60' was around a 2.0. It takes some driver skill to launch a manual properly, but you should be able to get halfway decent results if you can just put the power down and shift it at the right times.

Also, if you break up your posts into paragraphs and use some punctuation it becomes much easier to read. This isn't an English class but its hard to read a 300+ word single sentence :-/...
 

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Discussion Starter #9
Okay Ill take my time and write slower.
My car as far as I know is mechanically fine. I added a Vararam cold air intake and some magnaflows. I also unbenounced to me had a Granatelli throttle body on the car.
After I added these things I took it to my Dyno guy. He messed around with everything and got me 368 RWHP so the enging is healthy. I did just replace the granatelli with a Fast throttle body and have not gone back to the dyno. That being said I dont think that messed up my engine.

Track conditions that night were as follows. I live in florida so we were 88 degrees hot and muggie. I had a little more that a 1/2 tank and i put a bottle of Lucas Octane boost in as well. Tires were the Perelli Corsas (hook up great ). As far as my shift points go, I tried all different shift times. I tried to shift each gear at 6000-6300 rpm as that seemed to be where peak HP was at on the dyno. The shift points were adjusted and I was just breaking into 4th as I would come up on the finish line.

Okay I have my slips so I will put my 60' feet in order. My 1st run goes as follows
1-2.211 2-2.273 3-2.363 4-2.610 5-2.712
that all 5 runs
omn my best slip it went
R/T .509
60' 2.211
330 5.897
1/8 8.882
MPH 83.97
1000 11.385
1/4 13.501
MPH 105.93

I had one run 13.97
at 107 figure that out

This week IM supposed to put the long tubes and x pipe on so Im excited and down at the same time. Im hoping my dyno with bosst up with the added goodies but is it just going to make things more difficult. I also have a set of 410s I want to put on as well but real hesitant on that as well
Any more input is much appreciated

Jim
 

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Okay Ill take my time and write slower.
My car as far as I know is mechanically fine. I added a Vararam cold air intake and some magnaflows. I also unbenounced to me had a Granatelli throttle body on the car.
After I added these things I took it to my Dyno guy. He messed around with everything and got me 368 RWHP so the enging is healthy. I did just replace the granatelli with a Fast throttle body and have not gone back to the dyno. That being said I dont think that messed up my engine.

Track conditions that night were as follows. I live in florida so we were 88 degrees hot and muggie. I had a little more that a 1/2 tank and i put a bottle of Lucas Octane boost in as well. Tires were the Perelli Corsas (hook up great ). As far as my shift points go, I tried all different shift times. I tried to shift each gear at 6000-6300 rpm as that seemed to be where peak HP was at on the dyno. The shift points were adjusted and I was just breaking into 4th as I would come up on the finish line.

Okay I have my slips so I will put my 60' feet in order. My 1st run goes as follows
1-2.211 2-2.273 3-2.363 4-2.610 5-2.712
that all 5 runs
omn my best slip it went
R/T .509
60' 2.211
330 5.897
1/8 8.882
MPH 83.97
1000 11.385
1/4 13.501
MPH 105.93

I had one run 13.97
at 107 figure that out

This week IM supposed to put the long tubes and x pipe on so Im excited and down at the same time. Im hoping my dyno with bosst up with the added goodies but is it just going to make things more difficult. I also have a set of 410s I want to put on as well but real hesitant on that as well
Any more input is much appreciated

Jim
Much appreciated ;)

OK, I see a couple of things here that really stand out...
First of all you are clearly stuggling with traction. Your 60' times indicate massive wheelspin, which is exactly what I would expect from a 4000RPM launch. I usually launch mine at 2500RPM and I have much stickier tires than you. A clutch dump is also a good way to do a burnout, but not a good way to leave the line quickly. You'll have to slip your clutch to leave the line smoothly from lower RPMs without a bog, but you can't slip it too much since you are probably on a stock clutch and it'll glaze if you do.
This guy (Ranger) has had great success launching these cars; have a look at his launch tips as well. Don't get caught up on his "change your clutch fluid 3 times a day" sillyness though.
http://www.rangeracceleration.com/Launch_Tips.html

That's your 1st problem. Your second issue, as evidenced by your trap speed, is that you are down on power; running in hot humid conditions will make the engine pull back timing and you'll trap lower speeds. Open the hood between runs and let the engine cool down some. The tune may also be adjusted to run a less agressive ignition timing retard vs IAT or coolant temp table; talk to your tuner about that.
The headers will help power, but you're going to have to learn how to launch that car properly before it does well on the drag strip.
 

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Your 60' times are bad so that is a big part of why your ET sucks. Launching the car down at 2500 like Powerlabs suggested can improve the 60' but the result is that the car is out of its powerband. That hurts mph and isn't optimal for ET either. If you try that you need to work your way up to 3500 or more.

Next, you're short shifting the car. You need to shift past peak HP. When you shift, the motor drops back to where it makes less HP. The earlier you shift, the further down in the low HP range you land. Next time you go, shift at 6500. If you were shifting at 6000 rpm, that cost you 3 - 5 mph in trap speed and another .1 - .3 in ET.

88* and muggy is also going to reduce your ET and mph significantly compared to 60* and dry. Could be easily be .2 -.3 and 2-3 mph in the weather conditions compared to a more normal run.

Adding octane booster or race gas can actually make you slower if you're not tuned for it. Unless you're pinging, don't use additives. Even then you should address the problem (i.e. tune, mechanical, buy better gas).
 

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Discussion Starter #13
Yeah no water box went around it cooked the tires good and got them stickey.
I compared my 12.4 run to my 13.5 run slip and did notice a big difference in the 1st 60 feet . I did 1.93 verses a best 2.28 so the launch seems key
 

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Discussion Starter #15
This has helped significantly. I have been praticing my launches and Im doing 3500rpm and working the clutch out without any wheel spin. Also the long tubes go on tomorrow. When I told my dyno guy what happened at the track he laughed because he said he set the car up for road racing and actully detuned the car to make the air fuel mixture more even for long periods of full throttle. He said the way the car was set up at the factory has it was running very inconsistent air fuel and I probally would have had some engine problems if he didnt detune it. So of course tomorrow IM going to have him retune for the strip and not road course till I head back out to Sebring Raceway in August. Finally I will get the 410 gears in and Im told that will really help with the launch and keeping the car from bogging.
As far as fuel additives go!! The gas here in Florida sucks. My car pings always. I buy a bottle of Lucas Octane boost and the ping is gone. I will as my dyno guy about that as well
 

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Your guy should tune the car for the gas you have.

If you're getting a lot of pinging, before you do the headers, run a bottle of GM top end cleaner or Seafoam through the car and make sure oil and carbon deposits aren't the cause.

On an M6, a tiny bit of wheel spin on the launch is ok; you just don't want to blow things away. On automatics, I had my best results with zero wheel spin.
 

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Dissapointed

This has helped significantly. I have been praticing my launches and Im doing 3500rpm and working the clutch out without any wheel spin. Also the long tubes go on tomorrow. When I told my dyno guy what happened at the track he laughed because he said he set the car up for road racing and actully detuned the car to make the air fuel mixture more even for long periods of full throttle. He said the way the car was set up at the factory has it was running very inconsistent air fuel and I probally would have had some engine problems if he didnt detune it. So of course tomorrow IM going to have him retune for the strip and not road course till I head back out to Sebring Raceway in August. Finally I will get the 410 gears in and Im told that will really help with the launch and keeping the car from bogging.
As far as fuel additives go!! The gas here in Florida sucks. My car pings always. I buy a bottle of Lucas Octane boost and the ping is gone. I will as my dyno guy about that as well
Get a New Tuner ! I live in SW Florida & Run "NITROUS" & Never Had a Problem ... With Gas ! & I Run 3.07 Gears..... Don't change Gears Build More HP ! :woowoo:
 

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isn't it hard on the gears runing a low ratio ( numerically) in drag racing ?
I was always told that
Can't say I'm that familiar with the A6 .....I wish I could put one in a C5 though
 
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