going into 4th

**MiguelLS1** · 09-22-2007, 08:00 AM

My friend took my car to the track last night. It's a allstock ws6 but we put his dr's off of his vette. His first pass was a 13.38@104. He had to shift into 4th about 15-20feet before the finsh line. He ended up only getting three pass and on the third he went a 13.16@105. But he wants to know how everone else goings through the traps. He thinks he can go 12.80's with good weather and more seat time. Everypass got quicker. The tire size was 275/40/17 what tire will help it not having to shift? The 60' was only 1.94, 1.93, 1.92 he thinks it should be in the low 1.8 but did not get use to the car, since he never drove it before. Temp was in the 80's and very humid, and MIR was the track

**jrc1122** · 09-22-2007, 09:55 AM

I ran 13.75 @ 105.xx MPH -- street tires, and I only have Cat back and lid. So with DR I am thinking i can get 13.1 too.

The strange thing is I didn't spin that bad. I think I just need practice ripping through the gears.

**2000T/A Guru** · 09-22-2007, 12:19 PM

I ran a 12.87 in 88 degree weather with street tires, mods are exhaust, headers, lid, short shifter and im lowered 1 inch. With drag radials im hoping for mid 12s.

**clg82** · 09-22-2007, 12:27 PM

Originally Posted by jrc1122

I ran 13.75 @ 105.xx MPH -- street tires, and I only have Cat back and lid. So with DR I am thinking i can get 13.1 too.

The strange thing is I didn't spin that bad. I think I just need practice ripping through the gears.

13.7?!?!? my bones stock non ws6 ran 13.2 and it's an automatic.....

**MiguelLS1** · 09-22-2007, 01:50 PM

Originally Posted by 2000T/A Guru

I ran a 12.87 in 88 degree weather with street tires, mods are exhaust, headers, lid, short shifter and im lowered 1 inch. With drag radials im hoping for mid 12s.

when do you have to shift in to fourth?

**9T8W66** · 09-23-2007, 06:03 AM

To avoid shifting into 4th (M6) you would have to either alter the tune so you could rev the engine higher, or run taller tires.
With the 3.42's you should be shifting into 4th about 100 ft or so before the traps this puts your RPM in 4h through the traps at around 5-5200.You need a gear that will alow the engine to run close to redline through the traps.
This is why 4.10's are optimal for M6 cars cause they will alow the engine to stay in the sweetspot longer. A stock or mild car w/4.10's should redline (6000rpm) 4th gear at 112-115mph.
With 4.10 you'll have to shift to 4th and you should run through the traps around 57-5800 rpm.

**clg82** · 09-23-2007, 07:43 AM

Originally Posted by 9T8W66

To avoid shifting into 4th (M6) you would have to either alter the tune so you could rev the engine higher, or run taller tires.
With the 3.42's you should be shifting into 4th about 100 ft or so before the traps this puts your RPM in 4h through the traps at around 5-5200.You need a gear that will alow the engine to run close to redline through the traps.
This is why 4.10's are optimal for M6 cars cause they will alow the engine to stay in the sweetspot longer. A stock or mild car w/4.10's should redline (6000rpm) 4th gear at 112-115mph.
With 4.10 you'll have to shift to 4th and you should run through the traps around 57-5800 rpm.

does this work the same for automatics? and 3.73s?

**procsls6** · 09-23-2007, 09:43 AM

I am the driver of Migule's WS6 and I know that gear would make it go into the top of 4th. But will a different tire make it stay in 3rd. My Z06 has 3.42 gears also but I am in the top of 4th with the same tires as him. I know that they have different trans but I did not think it would be that big of a difference. Also what is the fastest a ws6 has gone with just a tire. I know that I could go a 12.90 but think a 80 something is not out of reach. It was my firs time driving his car, and I had to guess what rpm's to leave at.

**9T8W66** · 09-23-2007, 09:57 AM

Originally Posted by procsls6

I am the driver of Migule's WS6 and I know that gear would make it go into the top of 4th. But will a different tire make it stay in 3rd. My Z06 has 3.42 gears also but I am in the top of 4th with the same tires as him. I know that they have different trans but I did not think it would be that big of a difference. Also what is the fastest a ws6 has gone with just a tire. I know that I could go a 12.90 but think a 80 something is not out of reach. It was my firs time driving his car, and I had to guess what rpm's to leave at.

Yes your Z06 has a diffeent gearbox but it also has a 6500rpm redline vs the T/A's 6000 and a weight advantage.
A taller tire might allow the car to stay in third but taller tires effectively raise the final drive ratio aswell and this will have an adverse effect on acceleration through all the gears. It would be like going from 3.42's to maybe 3.23's
The stock 3.42 is more of a compromise on the side of fuel mileage, and CAFE requirements. For best dragstrip results these cars should of came with a 4.10 axle from the factory.JMO

**procsls6** · 09-23-2007, 10:40 AM

Originally Posted by 9T8W66

Yes your Z06 has a diffeent gearbox but it also has a 6500rpm redline vs the T/A's 6000 and a weight advantage.
A taller tire might allow the car to stay in third but taller tires effectively raise the final drive ratio aswell and this will have an adverse effect on acceleration through all the gears. It would be like going from 3.42's to maybe 3.23's
The stock 3.42 is more of a compromise on the side of fuel mileage, and CAFE requirements. For best dragstrip results these cars should of came with a 4.10 axle from the factory.JMO

I forgot all about the different redline. We are going to but gear in the car when we put all the other bolt-ons, but I want to get in the 12.90' first. Should be the next time I take back to the track. Thanks