Is this 10 bolt W-27 cover a reproduction or original? I want to believe it is a reproduction but have no idea how to tell. I found it on a 72 Supreme.

 

I think its a reproduction ?

 

My guess would be reproduction.

Casting looks to new,like a modern casting,does not seem weathered.

I think I remember reading original castings were more rough and porous looking.

 

Looks like a repop. Originals will have a part # or casting # on the upper middle right side if I recall correctly.

 

Definitely a repop. I was going to buy one exactly like that one off Ebay. But, then I changed my mind. No one is ever going to see it except the guy who does the vehicle inspection on it.

 

Why would you think its original? It is a 10 bolt? All W27 rear ends were 70 only 12 bolt? Not?

 

W27 rear end carriers were a '70 only option with W30, W31 and W32 packages only. The option W27 changed to just a cover in '71 and was available to any car in the fleet except the Toro IIRC.

 

how much do these covers go for on Ebay? i'll probably pick one up when i feel like changing my differential fluid again..

MAW add in some 3:73 gears..

MAW change the control arm bushings..

uh-oh

 

The one I saw went for $30 plus shipping. It wasn't a huge price. I think Tamraz sells them now.

 

Tony last I saw was around $69 plus the ride for a 10 or 12 bolt but technically speaking it would lower the operating temp in the differential and possibly extend the life of not only the gear oil but the gears themselves As far as the MAWs go what the hay it is only $ and time

 

Yikes!

I just looked it up and Tamraz sells them for $121. The one I saw was a private seller and the bid ended at $30 plus shipping.

http://www.ebay.com/itm/70-72-Cutlas...f57193&vxp=mtr

http://www.ebay.com/itm/1970-1971-19...184d95&vxp=mtr

 

I already have all the parts! I just need to actually do it

 

Reproduction. Here's mine before I put the OEM bolts back in, pressed in bushings, added the limited slip tag and filled it with fluid. I was trying to simulate the look of the W27 axle. Not trying to fool anyone into believing it's real:


LOL Good luck with 69 plus the ride. Best price right now is Parts Place - 89 plus ride. Yes it will lower operating temps, partly due to aluminum and fins. Also because it holds almost an extra pint of gear oil.

uh oh is right. You're getting into a big job there my friend. The only way you're going to change those control arm bushings is to drop the entire axle and remove the control arms (uppers and lowers). LOTS OF FUN! 3.73 gears? Don't go talking crazy talk like that - gas in Montreal is way too expensive for that kind of rpms. You can't do 3.73's anyway with your existing carrier. I think the most you can go to is 2.93. After that you need to swap carriers if going 3.08 or shorter. Want help?


Well then, that's a different story. Still it's a big job do drop out the axle and do all those things on your wish list. You know how I know.

 

How did you guess

 

I'll have to keep an eye out, when i changed my fluid last year, i actually painted my diff cover silver because i think the w-27 look is awesome.

 

The diff looks good with the center section in silver.
If I had a 70 to 72 I would do the same, from what I have heard and seen the real W27 diffs were not that great to beat on, more of a show item than a performance piece.

 

I think it looks awesome too. But, the only person who would see it is someone who climbs under the car.....which would be me or the guy who inspects my cars.

I may still get one. I could've upped the bid a little, but decided I wasn't interested. If I had known they are going for over $100, I should have bid, no matter what.

 

." Here's mine before I put the OEM bolts back in, pressed in bushings, added the limited slip tag and filled it with fluid. I was trying to simulate the look of the W27]. Not trying to fool anyone into believing it's real:"

Simulate, but not trying to fool anyone.
Ah...you're trying to make it look like the W27 axle, but, not the "real" W27 axle so as not to fool anyone? So, would it be a "clone" carrier or a "tribute" carrier?
Just kiddin with ya...the description made me do it!

 

Eric, the 71 and 72 W-27 covers did not have the part number on them like the 1970 models, and the cover you have pictured is a reproduction. Hope this helps.

 

I watched a 1970 W-30 drag race in the early 1970's, 4 sped car, and it never broke the W-27. It broke numerous muncies, and cracked the frame... The car was stock with headers and slicks. It ran consistent 12.60's.

 

Believe it or not that cover is actually really easy to see from behind due to the bright coloration.

LOL I guess you could say that. I prefer calling it 'purity'. I never really gave any thought to it being actually more than a glorified paint job on the housing, but the cover just looks cool. I bought that sucker years ago when it was a lot cheaper than today.

 

That is true. But you still have to bend down a bit or stand back quite aways. Another thing I should mention is that I had just bought quite a few things off of Ebay and I didn't want to press my luck with my wife!

I bid on it, but once someone outbid me, I left it alone for fear of the rolling pin coming towards my head!

 

So in car terms are you classifying your wife as a 'beater'?

 

The two that I now of both had problems one was a local car and it had gear/posi issues and the second one was a axle tube rotation issue with bolt on ladder bars. Both these cars were beat on. 12.60's with out hurting the W27 with slicks that is very good.

 

if you are in a car behind the car with the W27 cover you can actually see it, it is pretty noticeable. Its so dark under the car the cover sticks out. I have had multiple people pull up to me and ask what kind of rear end I have in my car because of the cover.

30 bucks for a repo cover is cheap.

I heard the full rearends broke easily as well, but I have never spoken to anyone who actually raced with one so maybe they were as strong as any rear end in the day.

 

Yes! Psst......whatever you do, dont say old beater....

But in truth, she's pretty lenient with my spontaneous ebay purchases.

 

I ended up buying a front passenger side marker for $7.00 (you can see it in the picture). Now I'm kicking myself for not buying the cover.

 

Yeah you're probably right Al... My car already guzzles gas at 1.35/litre that we're paying in montreal.

I'm just trying to find good ways of juicing a couple extra horsepower out of my car. My dad keeps telling me his old 4-4-2 could run circles around mine..

Need to prove the old man wrong.....

So far my upgrades are

Edelbrock 7111 intake (Performer RPM)
HEI ignition off a 75 Cutlass, rebuilt and tuned.
I did the timing chain.. but that was just for good measure. and she runs like a clock.

Maybe dual exhaust would help me out. I'm still running the single w/blockoff.

 

So how can we tell that this cover is a repo?

Don W

 

the originals had some sort of crispness to the lettering that the repops dont have, there was a thread about this once upon a time, but now it's just easier to post your cover and ask if it's a repop.

 

looks like a repop

 

That is cool because the smaller packages are always cheaper than the larger packages.

 

I would suggest that after being on a car for 42 years it's not going to look that good. Here are a couple pics taken of 2 (12bolt) covers. One is claimed to be original (which I believe), the other is from Supercars Unlimited. the quality of the repro is amazingly good. Technically the W27 10 bolt cover was only offered in 1971, but obviously it will bolt right onto the 72 since it's the same differential housing. There were no distinguishing marks on the repro I bought and bolted on. Since I'm not offering it up as original it's not an issue to me or anyone I discuss the car with. I just really liked the look. Sort of like the rear deck wing - not available in 72 but a lot of folks put them on because they like the look. Just saying.



This one belongs to a guy I found on the web - goes by jmskutnik, he says it is 100% authentic. If you want to check out his post, here is the link: Complete Original Olds W27 Axle


For those of you who are currently thinking of buying a repro cover? Parts Place is currently running a sale on them for 69.00 - your choice 10 or 12 bolt. Looks like there's a lot of interest based on the amount they've sold so far. Here's the link to the W27 Cover Sale if you're interested.

 

Thanks for the pics Allan.

With the original and repop side by side you can see the difference of the crispness in the lettering and edges Tony mentioned.

The original seems to have a smoother texture also.

 

Now I'm curious. I see the OEM W27 appears to have blacked out lettering/numbers and bolts. Hmmm, Joe has 2 of these. I'll send him and email and find out what's up. I agree the OEM cover looks a lot smoother - almost as if it had been machined or polished when new.

 

I was looking at what appears to be blacked out numbers,letters and bolt holes.

I was wondering if that isn't just years and years of accumulated crud built up.

 

Here's the cover as it was on the car.
HPIM1984.jpg

 

Looks nice,what kind of paint did you use on the center section? I like that.Might try coping that.

Here's mine,it's a Brian Trick built 3.42 posi with all new internals.Eaton,motive,timken.

 

Now, the W-27 covers for 1970 thru 1972 were available over the counter as a kit. The kit included instructions, gasket, and clear sinc bolts that are marked RBC. The W-27's used special bolts that were longer. The W-27 covers were not painted black, and not polished. The mounting surface of the covers were machined flat for a true fit, and the face of the cover was machined smooth. Some covers for the 1970 model had one fin machined off, and others were casted without the fin. An original cover will bring some serious coin and even more if it is NOS.

 

Brian does great work. I used Dupli Color High Performance aluminum wheel paint for my differential. It's an exact match and I love how it looks.


Thx Joe, saved me the PM. As always, great information sharing. I didn't use longer bolts, I just bead blasted the heads of the originals and painted them the silver matching color. They seemed to be long enough to do the trick.