Help me annalize time slips

L79racer · 03-21-2010, 07:43 AM

Need help analyzing time slips from my 5 speed Vega to my automatic Vette with the same motor and rear gears. In the automatic Vette am I loosing some up top because of the converter or could there be another problem that I should be looking for. I'm thinking a 6.46 to the 1/8 should be into the teens in the 1/4. Vega and Vette mph being different is due to stick to auto and Track altitudes. Let me know what you guys think. Vette was foot braked. How much can I pick up on the trans brake?

Vega with 5 speed / Vette with glide
60' - 1.473 / 1.449
330' - 4.29 / 4.164
1/8 - 6.627 / 6.46
mph - 106.28 / 106.39
1000' - 8.636 / 8.475
1/4 - 10.333 / 10.206
mph - 133.29 / 129.43

Chris "drooze" Wertman · 03-21-2010, 08:15 AM

Quote:

Originally Posted by L79racer

Need help annalizing time slips from my 5 speed Vega to my automatic Vette with the same motor and rear gears. In the automatic Vette am I loosing some up top because of the converter or could there be another problem that I should be looking for. I'm thinking a 6.46 to the 1/8 should be into the teens in the 1/4. Vega and Vette mph being different is due to stick to auto and Track altitudes. Let me know what you guys think. Vette was foot braked. How much can I pick up on the trans brake?

Vega with 5 speed / Vette with glide
60' - 1.473 / 1.449
330' - 4.29 / 4.164
1/8 - 6.627 / 6.46
mph - 106.28 / 106.39
1000' - 8.636 / 8.475
1/4 - 10.333 / 10.206
mph - 133.29 / 129.43

Sounds like some Preperartion H is required.....sorry couldnt resist....

Analyze.....is the proper vernacular....the other sounds like something well.....intrusive

And yeah I know my spelling can be atrocious it just was the first post headline I saw hehe....

L79racer · 03-21-2010, 08:35 AM

Quote:

Originally Posted by drooze

Sounds like some Preperartion H is required.....sorry couldnt resist....

Analyze.....is the proper vernacular....the other sounds like something well.....intrusive

And yeah I know my spelling can be atrocious it just was the first post headline I saw hehe....

I thought it was wrong so I typed into dictionary.com and it showed this. So I went with it. LOL! Thanks for correcting it.
Annalize
An"nal*ize\, v. t. To record in annals. --Sheldon.

Jeff Lee · 03-21-2010, 09:15 AM

You were inefficient with your clutch, running 4 tenths slow compared to your MPH (1320 / 133.29 = 9.90 ET). Now you have a PG that is running right on the formula (1320 / 129.43 = 10.198). See? Proof the formula works.
Now you are down 4 MPH because you took out the manual transmission. Your not going to get the 4 MPH back unless you ad more HP to the engine or get the weight down or make the Vega more aerodynamic.
Another 50 HP or so should get you your 4 MPH back.

L79racer · 03-21-2010, 07:22 PM

Quote:

Originally Posted by Jeff Lee

You were inefficient with your clutch, running 4 tenths slow compared to your MPH (1320 / 133.29 = 9.90 ET). Now you have a PG that is running right on the formula (1320 / 129.43 = 10.198). See? Proof the formula works.
Now you are down 4 MPH because you took out the manual transmission. Your not going to get the 4 MPH back unless you ad more HP to the engine or get the weight down or make the Vega more aerodynamic.
Another 50 HP or so should get you your 4 MPH back.

Jeff, I never got the clutch set on kill and I was only leaving at 4000. I'm sure with a higher launch it would have been closer to the 9.90 range. I am disappointed in the mph lose. Now should a 6.46 in the 1/8 be in the teens in the 1/4. Isnt this formula for 1/8 to 1/4 ET?
6.46 x 1.57= 10.14 Should I be working to get into the teens at that mph or is it not possible?

Jeff Lee · 03-25-2010, 04:13 PM

for 1/8th mile just alter the formula to 660/MPH = ET

I realize you didn't have the clutch "optimized". That can be difficult on a dual purpose car, too many compromises for street duty.
The MPH loss is just a fact of life when going from a manual race trans to a PG. You would spend a ton of money on an automatic trans to get that MPH back; and I'm not sure it is possible.
Dropping 4 MPH & only having 1 shift is like going down the track in slow motion, huh?

L79racer · 03-29-2010, 08:12 PM

Jeff, I found some HP. DA was -2022!! How about a new best 10.08 at 130.87 with a bad 1.42 60'. It turned the tire a bid. Not bad for a street car.

03-21-2010, 07:43 AM	#1
L79racer Member Join Date: Jan 2005 Location: North Massapequa, NY Posts: 218 Likes: 0 Liked 0 Times in 0 Posts	Help me annalize time slips Need help analyzing time slips from my 5 speed Vega to my automatic Vette with the same motor and rear gears. In the automatic Vette am I loosing some up top because of the converter or could there be another problem that I should be looking for. I'm thinking a 6.46 to the 1/8 should be into the teens in the 1/4. Vega and Vette mph being different is due to stick to auto and Track altitudes. Let me know what you guys think. Vette was foot braked. How much can I pick up on the trans brake? Vega with 5 speed / Vette with glide 60' - 1.473 / 1.449 330' - 4.29 / 4.164 1/8 - 6.627 / 6.46 mph - 106.28 / 106.39 1000' - 8.636 / 8.475 1/4 - 10.333 / 10.206 mph - 133.29 / 129.43 Last edited by L79racer; 03-21-2010 at 08:36 AM.

03-21-2010, 09:15 AM	#4
Jeff Lee VIP Member Join Date: Jul 2007 Location: Anthem, Arizona Posts: 2,766 Likes: 0 Liked 3 Times in 3 Posts	Re: Help me annalize time slips You were inefficient with your clutch, running 4 tenths slow compared to your MPH (1320 / 133.29 = 9.90 ET). Now you have a PG that is running right on the formula (1320 / 129.43 = 10.198). See? Proof the formula works. Now you are down 4 MPH because you took out the manual transmission. Your not going to get the 4 MPH back unless you ad more HP to the engine or get the weight down or make the Vega more aerodynamic. Another 50 HP or so should get you your 4 MPH back. __________________ Jeff Lee 7494 D/S '70 AMX

03-25-2010, 04:13 PM	#6
Jeff Lee VIP Member Join Date: Jul 2007 Location: Anthem, Arizona Posts: 2,766 Likes: 0 Liked 3 Times in 3 Posts	Re: Help me annalize time slips for 1/8th mile just alter the formula to 660/MPH = ET I realize you didn't have the clutch "optimized". That can be difficult on a dual purpose car, too many compromises for street duty. The MPH loss is just a fact of life when going from a manual race trans to a PG. You would spend a ton of money on an automatic trans to get that MPH back; and I'm not sure it is possible. Dropping 4 MPH & only having 1 shift is like going down the track in slow motion, huh? __________________ Jeff Lee 7494 D/S '70 AMX

03-29-2010, 08:12 PM	#7
L79racer Member Join Date: Jan 2005 Location: North Massapequa, NY Posts: 218 Likes: 0 Liked 0 Times in 0 Posts	Re: Help me annalize time slips Jeff, I found some HP. DA was -2022!! How about a new best 10.08 at 130.87 with a bad 1.42 60'. It turned the tire a bid. Not bad for a street car.