really cheap cai

Impetuous

Common sense isn't common
Established Member
Joined
Mar 27, 2005
Messages
707
Location
IL
I haven't. The Boss wants more RPM of course so I raised the shift points. Since it runs 6 more MPH now it traps about 7400 which isn't too terrible. The problem is a gear like that and coupling it with a 4.17 first gear, then trying to get it to hook consistently. If the track prep is good the car hooks well and will 60' not far off from what those mid nine second blower cars are doing. Unfortunately most of the time the track prep is not too good so it spins through first gear, shifts to second before 60', then finally gets hooked back up. There are so many good things about the 6R80, but the gear ratios are horrid.

I figured that it would be shifted higher and maybe you were trying a lower numbered gears. Due to the gearing on the 6r80, I have not being able to make my mind at all. I see that a lot of auto folks are switching to 3.31s and crossing the line in 3rd. I know that crossing at peak is what you should shoot for but around town with these lower uninspired gears makes it for a boring car. I have a set of 3.27s and 3.73s that are the ones I'm giving a lot of thought. Tires can make up for the difference in gearing if needs to, but at the same time if I ever decide to go forced induction I may have to make another gear change. Thanks for the reply!
 

wbt

Banned
Joined
Dec 28, 2010
Messages
715
Location
Texas
I figured that it would be shifted higher and maybe you were trying a lower numbered gears. Due to the gearing on the 6r80, I have not being able to make my mind at all. I see that a lot of auto folks are switching to 3.31s and crossing the line in 3rd. I know that crossing at peak is what you should shoot for but around town with these lower uninspired gears makes it for a boring car. I have a set of 3.27s and 3.73s that are the ones I'm giving a lot of thought. Tires can make up for the difference in gearing if needs to, but at the same time if I ever decide to go forced induction I may have to make another gear change. Thanks for the reply!

It really does come down to what you want to cross the line in/at. I went with a 3.31 for the reasons mentioned. Link to a spreadsheet that may help in making a decision:

Tire/gear spreadsheet
 

MikeLTDLX

Active Member
Established Member
Joined
Sep 19, 2004
Messages
2,174
Location
Mandeville, La
Everything is a go for tonight. Slicks are mounted, the box is back on the car and I have the JLT in the trunk. Will be data logging each pass as well as shooting video. Air is ok, it would have been better Saturday, but it will not be raining.

Mike
 

Red Turtle

ALWAYS WATCHING
Super Moderator
Joined
May 23, 2004
Messages
12,689
Location
Florida
Everything is a go for tonight. Slicks are mounted, the box is back on the car and I have the JLT in the trunk. Will be data logging each pass as well as shooting video. Air is ok, it would have been better Saturday, but it will not be raining.

Mike

:beer:

So what is the plan? 2-3 runs with Stock AB and then 2-3 runs with JLT..?
 

MikeLTDLX

Active Member
Established Member
Joined
Sep 19, 2004
Messages
2,174
Location
Mandeville, La
:beer:

So what is the plan? 2-3 runs with Stock AB and then 2-3 runs with JLT..?

That is the plan. I know everyone would like to see 3 runs for the sake of consistency, but unless the datalogs are showing something funky that needs to be corrected, the plan is 2 and 2. This is my daily driver and I would like it to drive me home as well. LOL. However, that may change, we will see.

We will also have a Pro-Cal auto out there doing the same thing. A couple of stock runs, then the Pro-Cal installed for the first time and a couple of runs on that.

Should be a good night.

Mike
 

SID297

OWNER/ADMIN
Administrator
Joined
Mar 27, 2003
Messages
55,705
Location
Myrtle Beach, SC
That is the plan. I know everyone would like to see 3 runs for the sake of consistency, but unless the datalogs are showing something funky that needs to be corrected, the plan is 2 and 2. This is my daily driver and I would like it to drive me home as well. LOL. However, that may change, we will see.

We will also have a Pro-Cal auto out there doing the same thing. A couple of stock runs, then the Pro-Cal installed for the first time and a couple of runs on that.

Should be a good night.

Mike

I don't think you have to worry about hurting the car. The stock clutch is pretty stout.
 

Impetuous

Common sense isn't common
Established Member
Joined
Mar 27, 2005
Messages
707
Location
IL
It really does come down to what you want to cross the line in/at. I went with a 3.31 for the reasons mentioned. Link to a spreadsheet that may help in making a decision:

Tire/gear spreadsheet

Thanks man! I just hate the fact that unless you are wot the car feels slugish. The problem with steep gears are the 4.17 ratio in 1st. That may cause some traction issues and become unuseable.
 

MikeLTDLX

Active Member
Established Member
Joined
Sep 19, 2004
Messages
2,174
Location
Mandeville, La
I am back, guys. I had a terrible night racing. Traction issues, missed shifts, tire sway. I made 6 passes, 4 on the box and 2 on the JLT. First two box passes were wastes. The second and third were crap 60 foot runs and a 12.5 and 12.6. I was disgusted, but I bolted up the JLT and went out anyway. I immediately went 12.1 with the JLT and then essentially hot-lapped it to a 12 flat. Never broke out of the 12's tonight and never cracked below a 1.7 60 foot. I will post the full story tomorrow. I just sent Shaun the logs for his review.

In my honest opinion, the JLT worked. I was struggling all night with a crap track. Plus it was humid and windy. We had a wicked head wind. As soon as the JLT went on, the car woke up and pulled through the 60 and just ran better.

However, I know the test is inconclusive and I blame myself. I just could not get it together tonight. I will check the DA tomorrow and see what I was up against.

Best pass was 12. 043 @ 114.74 with a 1.74. Best mph I ran with the box was 112.98.

I am beat, and I have to get up in 5 hours to swap off the slicks.

Mike
 

Users who are viewing this thread



Top