Well, finally plucked up trhe courage to go for a ride with the new gears installed - no dice - battery flat

Charged battery, did about 25 miles, including some motorway (freeway?, highway?, whatever you call it.)

The back wheels turn round, and there is no whine, so it will do for me. Guess I must be very lucky

The 3.54 ratio is GREAT compared to a 2.59. breaking the back tyres loose at around 30 mph is no problem, and doing 80 -85 on the motorway is not too busy. I would recommend to anyone.

So thats it, finally finished all the mods on my C4, just enjoy driving it now


(PS what's this about a 2600 stall converter?)

 

Sounds like a successful project. 2600 converter !! Tires will be smoking.

 

That much of a ratio change ought to feel as if you added 50 HP. The convertor will let it launch at a much higher RPM. You'll want to do your research and make sure you don't over do it for your purposes. Anything from 2000 to 2600 would work well and be a noticable change. Good luck and enjoy that American HP that we're glad to share with Euro brethren!

 

Just for my knowledge, did you measure the backlash? I'm getting ready to do 3.91's in my D44. I know the magic number for an 8.8 ford but I have never done a dana.

 

Congratulations! I'm glad it all worked out.

RACE ON!!!

The backlash is the EASY part. Right, britvette?

RACE ON!!!

 

The backlash was specified as .008 + or - .004. I figured more is better than less, especially with an auto., so I got it to 10 - 11 thou.

To measure the backlash I made a holder for my micrometer (out of a short piece of exhaust pipe) which bolted onto the diff case. This meant I could measure to within approx 1 thou.

The hard part is the pinion depth.(special tool me no have), and CFI gave me some good info and suggested a viable method on this one, (thanks CFI) - trouble is I chewed up the old shims getting the old bearing off - but I reckoned pinion depth is only a way of getting to the correct tooth pattern, so I thought progressive iteration (OK, trial and error) would have to be the way.

Problem here of course is that means the bearings would have to come on and off a few times, and they are a TIGHT fit.

So, I took the old bearings off the old gearset, put them on the lathe and ground the inner face down with a stone so that they would slip on and off easily. These I could then use as checking bearings to determine the correct number of shims.

To get the pinion depth in the ballpark, I put one stub axle in and eyeballed through the other stubaxle hole with a digital vernier inside the case. I reckoned I could estimate to within a couple of pinion shims either way by this method.

Plenty of time, plenty of engineers blue, and I thought it was about right.

Now here is the really clever bit - then I took it to a pro, and asked him to check my work! Got the green light, swapped the checking bearings for the new bearings and nailed it back together.

Just hope it lasts now, I really don't want to take the axle out again.

- Oh and about the stall converter, that was just a joke. I don't want a new converter. Really. Not at all. No way. Silly idea.

(I hear Vigilante are pretty good?)

 

Do you performed this on a Dana 36? or 44?

 

doing 80 -85 on the motorway is not too busy. I would recommend to anyone.
What rpm at 80 in OD???? Thinking of doing this too.

 

36

Dunno - I was too busy listening for nasty noises

Less than 3 grand though.

Iam not sure I would actually recommend doing it yourself, by the time I had made the special tools and had it in bits a zillion times, I was pretty sick of the sight of it.

If your as sad an individual as me it's OK though.

 

Does your car see the drag strip? If so I'd love to see before and after results.

 

Not yet, but there is a strip in York (that's the old one, not the New one), about 30 miles from me, maybe next season. I have never been to a strip, so the car might be OK, but I'm sure I would be rubbish. (insert silly smiley of your choice).

 

I am so glad it worked! Now, cruise over to Santa Pod and get some numbers!

 

Yup, just as sad. I refuse to pay anyone for what I can do myself.