1st 1/4 mile times

[354RwHpLT4CE]

Well,Just got back from "test and tune". I dont know whether I am happy with these times or not.ALOT of traction problems.First run: 13.023 @109.97 w/.478 R/T & 2.218 60ft.@ 2nd run: cry )13.763 @107.92 .678 R/T 2.557 60ft(forgot to turn off ASR :duh )3rd run:13.402 @107.82 .412 R/T 2.26 60ft(smoked the tires thru first) 4TH run:13.439 @109.27 .697 R/T 2.421 60 ft(smoked em off line,then pedaled out) 5th run:13.143 @112.84 .305 R/T 2.309 60 ft(no smoke,tried slow take off).Last run:12.941 @111.18 .174 R/T(almost a redlight)2.190 60ft.puke )First 3 runs I drove around the burnout box,the last 3 I heated the tires pretty well. I need slicks(or a better driver).What do you all think?

 

[Gman]

Sounds to me with a bit more track time you'll be knocking at least a few tenths off your times. Throw on some slicks and you may be in the low 12's. Nice!

 

[Edmond]

Those times are pretty good despite the lack of traction. How much tread do you have left? What kind of tires are you running? At what PSI?


I :BOW to you M6 guys. Driving those ain't easy!

 

[warren s]

Those 60 foot times, and the high trap speeds clearly show traction is an issue.

My pokey 95 runs 13.4 with the ASR ON. If I leave it off I spin off the line. (1.9 60 foot time)

With a little more practice and some slicks I think you would be looking at mid 12.s. Dont worry about your R/T now, the clock dont start untill you do.

 

[DRTH VTR]

If you are running stock street tires, I would suggest staying out of the water box. I got some extra rims and some drag radials and my consistency has improved. I also spin a whole lot less. For rims and tires it ended up costing about $900.

 

[354RwHpLT4CE]

Those times are pretty good despite the lack of traction. How much tread do you have left? What kind of tires are you running? At what PSI?


I :BOW to you M6 guys. Driving those ain't easy!

Thank you.I just bought the Goodyear F1 GS-D3's,they were at 32psi(I know,I should have let some air out)They really have pretty good traction,for a non-drag radial.I saw alot of guys running the Nitto 555r drag radials.I think I will get some of those.I want to be able to drive it to the track.By the way,there was a c-5 out there with a stroked 390 something LS1(wasnt a 396)anyway he was running 10.98's!!!He said he still gets 30mpg! All motor baby!Gotta love that.Even at the track,the corvette comradery remains,thats what I love about these cars,Its not just the car,its the history.Thanks for the praise fella's.Save the wave!

 

[Edmond]

By the way,there was a c-5 out there with a stroked 390 something LS1(wasnt a 396)anyway he was running 10.98's!!!He said he still gets 30mpg!

Wow, that's awesome.

I think you're putting down power very close to stock Z06 numbers. But their cars are lighter.

I would try lowering the PSI's and even going as far to take off the spare tire and tire carrier. Maybe the combination of those two is good for something?

The downside to getting drag radials is that even though you grip better, your tranny better be able to handle the power transfer.

Also, there's a thread in the Z06 forum about 1/4 mile times and they talk about some launch techniques. Check it out.

 

[sothpaw]

you can do better--here are some tips

You have ported LT4 heads, right? You should be faster than me. Maybe you need a better custom tune.

I got 352 rwhp and 336 rwtq at the dyno, and just ran 12.57@ 114.9mph best on Saturday. My 60' times were around 2.0 s consistently, I couldn't do better with the crappy track prep at that track. Temp was 65 deg and humidity low for Maryland.

You do better than the above (I have a 1993 M6)

1. Avoid the water box like the plague.
2. Set your tire pressures to 22 psi and experiment from there.
3. After the burnout box, on way to the line, rev to 4000rpm and spin
the tires. This will clean off the excess debris.
4. If you suspect a crappy track prep by your track operators (I do from your 60 times), try a launch @ 2500 rpm. If tires still spin, try less rpm on your next run. If car bogs down (a momentary pause then go), you need more rpm.

Enjoy

 

[Edmond]

I got 352 rwhp and 336 rwtq at the dyno, and just ran 12.57@ 114.9mph best on Saturday.

Andy, I :BOW to you!

 

[DRTH VTR]

That is very fine! For reference, this is my stock Z06:


Elevation 2600' about 70 degrees, track about 110 degrees
Time trial #1
60' 2.017, 12.873 @ 111.12
Time trial #2
60' 1.845, 12.638 @ 110.89
Time trial #3
60' 1.810, 12.549 @ 111.28
First bracket run
dial 12.50, 60' 1.928 (bogged), 12.721 @ 111.89 win, the other guy broke out
Second bracket run
dial 12.57, 60' 1.847, 12.479 @ 112.24 lost, broke out (but happy!)

I always knew the LT4 was stout. What did you do to it?

 

[sothpaw]

No, just Lt1

[I always knew the LT4 was stout. What did you do to it?[/QUOTE]
Darth,

Assuming you mean me. I don't have an LT4. I have an LT1. I just ported the heads and added a mild cam (more mild than the hot cam), along with valve train stuff to support the cam, and cat back exhaust. I run stock headers and cats, stock ignition.

Edmond,
Thanks. It's no big deal, just a lot of fun. The M6 is not so bad to launch with good street tires and practice. Auto is probably much better--I've never done that though.

 

[354RwHpLT4CE]

1/4 mile times

Thanks SOTHPAW.Yeah, I have LT1 edit,so I can make adjustments,I think I may have some other small issues with the car also.I have a bad fuel check valve at the sending unit,so my fuel pressure may not be holding very well.And I may need to mess with my PE tables on a dyno.The Track conditions were pretty bad the night I ran too,but mostly,it was just me having trouble getting out of the hole without smoking the tires.I am in the process of fixing many problems that recently popped up with this car.i.e...climate control,cruise control,pass.window,alternate air check valve,wheel bearings.Jeez!Everything goes at once!:eyerole Anyway,yeah from seeing some of the other folks cars with the same mods I SHOULD be looking for 12.20's to 12.50's.I will fix all this stuff and take it to the track again,maybe I will make some better #'s.Thanks Yall!

 

[UB2 SLOW]

. Avoid the water box like the plague.
2. Set your tire pressures to 22 psi and experiment from there.
3. After the burnout box, on way to the line, rev to 4000rpm and spin
the tires. This will clean off the excess debris.
4. If you suspect a crappy track prep by your track operators (I do from your 60 times), try a launch @ 2500 rpm. If tires still spin, try less rpm on your next run. If car bogs down (a momentary pause then go), you need more rpm.

Enjoy

I agree! Traction appears to be your enemy right now. With that HP you should be running about the same as me, 12.2@115.

 

[354RwHpLT4CE]

1/4 mile times

I agree! Traction appears to be your enemy right now. With that HP you should be running about the same as me, 12.2@115.

Yeah man,Your car was pretty much what I was talking about!:BOW Thank you for what you did in Iraq,dude. I have been wanting to ask you about your setup and tune.What are ALL of your mods?Did the fuel pump change make a noticable differance?

 

[Shriker]

Lot of good advice here ..... with better 60 ft times your et's will vastly improve and so will trap speed . Get some drag radials , mine REALLY hook - I have Nittos but BFG's are pretty good too. My car typically dynos 375+ (with 4.10 gears) and has gone 12.0@117 .

 

[UB2 SLOW]

Yeah man,Your car was pretty much what I was talking about!:BOW Thank you for what you did in Iraq,dude. I have been wanting to ask you about your setup and tune.What are ALL of your mods?Did the fuel pump change make a noticable differance?

Whoa, sorry about the really late response. Thanks, I cant wait to get back home. Here is a list of all my mods; Vortex ram air, 53mm TB, TB coolant Bypass, LT4 Intake ported to match the TB and the Heads, Stage II port & polish LT4 heads, with 1.6 roller rockers, Hooker Shorty headers, LT4 Hotcam, Extreme Duty timing chain, 8.5mm Taylor wires, Walbro 340 Fuel pump, #30 accell injectors, Fast Chiip programming, Adjustable fuel pressure Reg set at 47psi, Transgo Shift kit, Transmission cooler, 3:73 gears, yank 2800 TQ convertor, Eliminator exhaust and 315/35/17's to help with traction. I was having allot of problems on take off and on the top end. The dyno was showing very eratic curves at the low RPM's and the higher Rpm's. We but the Walbro 340 in and pushed the fuel pressure up from 45 to 47psi. After that, no more eratic power curve.

 

[CKA_Racing]

Sorry but i run better times than that in my stock LT4, best run 12.9@110mph.
You need more practice, simple as that. Using slicks will make your times more consistant but your drive train will be abused alot more with the slicks. Ask yourself is it worth an extra possible .04 just for bragging rights if you use slicks?

If you have EMT's get ride of them, the sidewall does not flex enough to get good traction compare to a non-emt. Use around 26-28psi on the rear tires. Take the fronts to max psi. Drive around the water box. I also leave from the at idle. It's easier on the drive train. That's all I do.

You can also remove your front sway bar, that will allow more weight transfer to the rear. You can switch over to drag shocks also. You can also spray on some VHT on the rear tires for more traction but that stuff makes your tire rubber rock hard after a while. slicks are good if you do not want to wear out your street tires and are looking for consistance and slightly better times.

 

[MoeJr]

With a trap speed of 113-115 with traction and good driving you can hit low 12's to high 11's. My 87 GN when I had it ran 12.34/113 on the street tires(215/65/R15) but I practiced alot to get there. With drag radials I had the goods to run 11.80's.