Unplanned mods - Gearbox and Diff

[oztrack]

Just wore out my box - 1st gear to limiter and 2nd gear all slip. So have just had Craigs Automatics build me a good 4L65e with all the best parts. While the box was out i got criag to send the converter away to dominator and got them to modify it to a 4000-4200 stall speed.

It changes super quick but with the converter is still nice on the street. At WOT though its like a pro stock fast sound :)

Driving around with it this week i noticed my LSD is clunking badly and the diff has been whining for a while. So after about 200 runs this stock LSD will be replaced with a reconditioned 4.11 in a couple of weeks time.

The effect of the stall is good. It is almost instant smoke now if i engage just 2nd gear and stomp it. Its similarly tight too before but will be more agressive off the line.

With the 4.11s i have calculated that it wil be crossing the traps at around 7050rpm at 120-123mph if it stays in 3rd. But Craig has confirmed that the box is all the right stuff for WOT 3-4 changes no problem. So in a few weeks time we will see.

The goal will be 11.0 in AC Delco - its been a tough goal but its creeping closer. Markone2 just tested some 4.11s in a Caprice against some 3.91s and gained about 0.08s/0.9mph and that was in a 11.7/114mph car. So im am hoping that the box and gearbox can grab me about 0.2s plus.

[BOMI]

Will be very interesting to see what happens to your car now that its got 4.11's in it. Fuel econ with get a bit worst yeah? What RPM would you be doing at 110 kmh Steve?

Could you please PM with how much your new "Built" 4L60E was please.


Cheers,


Troy :)

[NickS]

Could you please PM with how much your new "Built" 4L60E was please.

4L65E actually Bomi.

Good stuff Steve, would be awesome if you can get the car running consistent 11.0Xs. Is it possible to get this close to a 10 consistently without managing to drop a 10th accidentally ? Any plans for a cage ?

Good luck.

[oztrack]

Usually during a meet the time barely moves within a meet. It just drifts in ET with temp and pressure. The biggest risk would be if it did i first up in a meet when its cold. If it got cold later in the night - i would guess it is going to be close and take it easy. sub11.00 would be a break out anyway. It will still be hard to go below 11.00 i think maybe just under 11.1.

I worked out that at 109kph it wil rev like it does now at 120kph. I drive too fast on the freeway anyway so it should slow me down. It gets just under 10L/100km now at 120kph so economy it should be OK and it will make the car need less throttle at slower speeds so im - guessing it might not make that much difference where i drive the car these days. No trips needed in it. We use the Forester. I will be able to get the car to lock the converter with 4.11s, now its at 64kph but could be shifted to 58kph for same rpm.

Interesting that Markone2 just did about a 0.079s/0.943mph quicker with 4.11s than 3.91s in a stalled A4 11.6s caprice. The predicted gain at the same rate for 3.73 to 4.11 (if its all a fair test) is 0.15s and 1.9mph.

So im hoping for a gain of around 0.25s all up from both.

The box work cost was around $3300 plus the extra work on the converter.
I had a 4L65e to build up. People are best to ask Craig for prices - it all depends on what is put in it. This one has all the good stuff and can handle 3-4 WOT changes if i dont want to ring the engines neck in 3rd with the 4.11s.

[BOMI]

Thanks Steve.

Nick I knew that :lmao:

Troy :D