I want to burn some rubber

68conv4sp

New Member
Oct 24, 2005
270
0
0
The rear end (8") in my 68 4 speed was rebuilt a couple years ago with 3.00:1. Nice on the highway but no tire smoke! Will a 3.5:1 break the tires loose with a stock 289? Can I do the swap with no rear end experience?
 
  • Sponsors (?)


The rear end (8") in my 68 4 speed was rebuilt a couple years ago with 3.00:1. Nice on the highway but no tire smoke! Will a 3.5:1 break the tires loose with a stock 289? Can I do the swap with no rear end experience?

The swap is easy! Just did my first one from 3.00 to 4.11's. Pull the wheels, removed the axels from the tubes, unbolt 12 nuts, let fliud drain. Repeat in reverse order. (That is if you buy a third member already assembled. IF you're looking to do the entire third member, it will require a press and other tools to measure backlash, etc)
 
Where did you buy your 3rd member? I bet the 4.11 is a blast.

I got it off ebay for $600. Pretty good. I took it for her first ride yesterday to work out some bugs (new front brakes with calipers and slotted discs) new gauges, new rear. So getting on it wasn't top prior (yet). I have an AOD so I'm not worried about highway :D .

I tried power braking but the rear brakes seemed to work too good and kept my RMP's down when I trying burning them. :shrug: Need practice I guess.
 
Man, if you can't break a tire loose with 3.00s and a 4-speed on a stock engine, there's a problem. My '65 coupe had a 3.00 peg leg rear and a 3-speed with the stock A-code 289 and it would spin the heck out of the right rear.
 
I've never had trouble burning down tire with 3.00s.

Don't even consider the 4.11!
That gear behind a stock engine will make it feel like you are driving a dump truck!
I did it once and it felt like you would go about 10 foot before you had to shift into the next gear. Felt just like driving a big, cumbersome truck.
 
You should have your compression checked. That could be your loss of power. My friend had power loss from having four broken head studs (on his porsche) which caused low compression not to mention a few other things! we figure about 50-60 horses were running wild! thats alot. The car will be much more fun now especially with the new cam he got!
 
You got a couple things going against you that most folks strive for:

Sticky tires
Limited slip

Then, you got a stock engine with 3.00 gears to top it off.
Even with 3.55s, you are gonna have to lose the sticky tires.
 
Smokin' tires w/ a 4 spd is not that easy to do. I also have a 289 (although definitely not stock) w/ a toploader and 3.50s. I'm running 295s in the rear and when I start even fairly hard my tires will spin for a little while but I also would like to be able to just smoke 'em. With an auto trans power braking will let do it easy but is there a way to keep from launching while keeping the tires spinning with a manual trans that isn't bad for the clutch?
 
Smokin' tires w/ a 4 spd is not that easy to do. I also have a 289 (although definitely not stock) w/ a toploader and 3.50s. I'm running 295s in the rear and when I start even fairly hard my tires will spin for a little while but I also would like to be able to just smoke 'em. With an auto trans power braking will let do it easy but is there a way to keep from launching while keeping the tires spinning with a manual trans that isn't bad for the clutch?

Install a line loc on your front brakes and do your burnouts in 2nd gear. You'll take em' to the threads in no time!
 
I just read about the line lock myself and am wondering how it is used? do you just push a button and the front brakes go on only or is there more to it?

You push the brakes hard to the floor and THEN push and hold the button. The brakes will remain on as long as you are depressing the button. You no longer need to use your foot to hold the brake as the electric solenoid will maintain pressure to the front brakes. As soon as you release the button, the brakes release too and will not activate again until you do the whole sequence again.
 
Smokin' tires w/ a 4 spd is not that easy to do. I also have a 289 (although definitely not stock) w/ a toploader and 3.50s. I'm running 295s in the rear and when I start even fairly hard my tires will spin for a little while but I also would like to be able to just smoke 'em. With an auto trans power braking will let do it easy but is there a way to keep from launching while keeping the tires spinning with a manual trans that isn't bad for the clutch?

2 ways to spin with a manual:

1: Rev and let most of the way out of the clutch as if you are doing a hard take off. However, you do not want to let totally out of the clutch. If you do, you will only spin a little. Keep the clutch pedal right on that 'sweet spot' where it is right on the edge of being engaged yet slipping some so your RPMs stay up.
You won't stay put like power braking, but you won't be going anywhere fast either. You will just roll forward slowly while the tires smoke up, then when you let off the gas and clutch (keeping it in gear), your rpms will fall back to idle, but the car will lurch forward very hard. Very pro-stock style burnout is the comment you get from bystanders.

2: Push the clutch in with the left toes while keeping the left heel on or very close to brake pedal. Rev and dump the clutch while simutainiously lightly holding the brakes with your heel. You can't lay on the brakes hard, just enough to hold you with the front brakes while letting the rear spin.
It is basically the same as doing a power brake with an auto, just have to do fancy footwork.
If you push the brakes too hard, you will stall the car or burn the clutch rather than tires. If you push the brakes too light, you will gain forward momentum and not be able to attain stationary power braking, which will require you to start all over. Once the car is rolling more than a creep, your brakes will never get it stopped again.
This method also does not allow for you to keep the pedals stationary. You do have to feel what the car is doing and make slight adjustments on brake pedal pressure and throttle the whole time or you will over-rev and/or overcome the front brakes.

Also, all you gung-ho types with late model cars that want to put this to the test, make sure your traction control is off!:nono:
I used to do this with my LS1 Z28/T56, and it works very well...
However, the TCS was 'default on' and I forgot to shut if off once.:bang:
I was holding 5k rpms in stationary position, smoke just boiling out from under the car, grinning ear to ear. Yet all my buddies outside the car had a puzzled look on their faces... The clutch was smoking, not the tires!
Didn't hurt anything but my pride. :D
 
well while you guys are talking about line lock, ill let you know cuz i just got it in today. I have the jegs line lock with install kit in my car, front slotted discs, and the sidewinder whifter knob with the line lock switch on it. The line lock is amazing, just hold the brake to the level of firmness you want, then hold the button on the shifter and release your foot from the break and then go to town while holding the button, then release the botton when you want to roll out of it, only bad thing is i am going to go through tires soooooo quickly now hahahaha:SNSign:
 
I've never had trouble burning down tire with 3.00s.

Don't even consider the 4.11!
That gear behind a stock engine will make it feel like you are driving a dump truck!
I did it once and it felt like you would go about 10 foot before you had to shift into the next gear. Felt just like driving a big, cumbersome truck.

Very good advice.

The 3.50 is a good street gear.

My road race track car uses a 3.89.

HistoricMustang
www.historicmustang.com
 
I have a line lock in our track car and have had one in my my daily driver for years. I put one in my daughters car too. They are fun. I had a tech. guy ask me one time at the track what that gold thing was. I told him it was a line lock... " You got to be able to do a big burn out"! ... He didn't say anything and signed the tech. sheet.

turn71.jpg

You can see it under the MC if you look hard.

John
 
i used to get the revs up and then dump the clutch and jump on the brake with my old 76 capri with the 2.8 v6, after a while i developed a technique similar to what ratio described but using my right foot on the brake and gas more like heel/toe downshifting on a road course, but then i'm a goofy foot skateboarder too.