Woo-hoo, got a TrueTrac in my V8

[benny]

After over a decade of telling people "No, my V8 Cortina gets surprisingly good traction for a car with an open diff" I finally broke open my wallet, and sprung for a TrueTrac differential.......what a difference!!

Now I can go round any bend in any gear and just punch it without hesitation. There is a momentary 'wiggle' while the diff does its magic, and then the car just rockets forward with no drama whatsoever. I should have done this 10 years ago!!

[zombie289]

Is that the one Eaton make Benny?? does it 'clunk' or unload abruptly around corners??

[benny]

I believe it is made by Eaton, and works on very much the same principles as a Quaife. As long as both rear tires are sensing resistance, it handles the rest for you, but if one rear tire comes off the ground it becomes an open diff. Luckily, Cortinas don't seem to pick up rear wheels, so it should work very well in all conditions.

When I went to the differential shop, I had my mind made up on an Auburn Locker. The guy asked me what I do with the car, and when I told him it's a weekend warrior for the mountains that does the occassional track-day, he told be the Auburn was not a good choice as it would not unload smoothly and would tend to make the car push.

He told me that after the installation of the TrueTrec, I would think I had been ripped off because I would notice no change in the nature of the car.......no change until I exited a corner with my foot down. He was dead right.

There is absolutely no discernable change around town....no racheting, no clunking, no chirping tires. I can do U-turns just the same as before.....there is no difference whatsoever until you romp on it. It's the best $700 I've ever spent on any of my cars.

[zombie289]

Good stuff mate, I was sorta thinking of putting one in my Falcon, but you've convinced me!

[jewels]

ive heard of these
for a 9 inch

recommended as a good compromise for strip and street

[benny]

Yeah, I hate to sound like a salesman for the thing, but I just took the car out for a thrash this morning, and can't find a single thing I don't love about it.

The 8" version is apparently a shortened down 9", so it is also very strong.

The part itself is $550, then I had it installed in my "pumpkin" for $70, plus all new bearings, and I think the total came to $717 with tax.

[Bertil]

Sounds great! I know what such an modification does to a car. But only having done it to english Cortina axles and payed up more than the double of what you payed I must ask what axle you have on your car.

[benny]

I must ask what axle you have on your car.

A narrowed 8" Ford.....out of a mid-70's V8 Mustang, or V6 Pinto estate.

I can go to the scrapyard, and get the axle housing, and two short half-shafts for $75. Then you shorten one tube down by 4", and it's dead-on the correct width for a Cortina, and even has the correct bolt pattern.

You have your choice of ratios from 2.88 (which is what I have) to 4:30+, and you end up with an axle that is absolutely unbreakable (with a brand new TrueTrac) for less than $800 US. If I didn't care about an open diff, I could honestly do the swap with all new brakes for just over $100.

I know shipping would be daunting for the guys elsewhere in the world, but I bet you might get your money back over time, and end up with better durability, and wider options in the long-run. You could ship the axle housing in two pieces, ready to weld back together, and I'd bet the shipping wouldn't be too hard to swallow.

[jewels]

benny who makes these true tracks ?

[Dr Danger]

Detroit/Eaton

[jewels]

is this the diff

HERE ? (http://www.vpw.com.au/productgroup.asp?CatID=758&SubCatID=841&priorCatID=841&PrdGrpID=2798)

[garyeanderson]

Summit racing (super market racing parts warehouse) offerers them for cheap money for most U.S. makes, it looks like a few offerings from Japan also.

http://store.summitracing.com/egnsearch.asp?N=700+400949+314530+115&Ne=100651&NeXID=100651

Gary

[jewels]

would they be suitable for any strip work i wonder ?

[garyeanderson]

A spool would be a lot lighter than the truetrac, especially for the 9 inch. while your shopping maybe get one of these.

http://store.summitracing.com/egnsearch.asp?Ntt=MSR-3062ALU&searchinresults=false&Ntk=KeywordSearch&DDS=1&N=700+115&x=37&y=10

[jewels]

yea but i dont want a spool for driving on the street

not going LSD this time either
not the best for strip work

gary i already have a aluminium housing /carrier :) HERE (http://www.cortina-mk1.com/diff.php)

[Dr Danger]

Those alloy centers seem pretty cheap though Jewels? Cheaper than the one in the 4 door?

[benny]

would they be suitable for any strip work i wonder ?

In a Cortina?.....I think it would be fine.

The owner of the shop where I had mine installed was putting 800 hp through his in his Corvette for a while, but it broke when he hit it with the 400 horse shot of nitrous.

[geoff]

it seems the truetrac is sold under many brand names, but its nothing new .it was fitted to all mercedes unimogs since 1960s. they are big time in 4x4 rock crawlers.and seen in military use. they are a revised torsen screw type gear assembly. have been fitted to many hp cars over the years,they come as standard fittment to xr fords in aust, dr danger and jewles saw some an the weekend,even touched one but i dout they even knew what they were touching.:)

[jewels]

benny, well i wont be seeing that much HP i can tell ya :)

[geoff]

dr danger, $485.00 is only the bare case through in alloy pinion support,6 bearings ,front seal,hardened washer kit ect. $1000.00 now + ++ freight,ring and pinion set,steel hemisphere,lsd kit or whatever side gear kit in 28,31 ,35 spline you need ads up real quick. no housing or axles yet then pay somebody to put it together without stuffing it up. (another head spin)..... :) :) :)

[Dr Danger]

Hearing ya loud and clear Geffro. Just thought that with the Aussie dollar these days that getting the actual parts cheap from the states might offset some of the costs...?