how's this sound 7.5" drag rear-$300?

[Minion1186]

I found a local whos son drag races a 78 malibu,its runs 1120s consistently and has 520 horsepower.I was talking with his dad the other day and he said his son has a 7.5" 10 bolt,with a c-clip eliminator kit,4.56 gears,a mini spool and moser axles.He doesnt know what spline axles are in it but he did mention it was in the 78 and was ran with slicks down the quarter mile.Anyway,he wants to sell it because they got a 9 inch rear for the 78,he said somewhere around $300 he'll sell it.Since i am not worried about gas mileage with the cutlass since the 355 was put in,i want it,does it sound like a good deal?
And the only thing with it is,when it was in the 78 running the track,something happened with the ring and pinion and the gears that were in there got screwed up.This rear is partially assembled,just needs the new gears put into it.

 

[beermonkey9417]

it sounds good, but that rear has been used pritty hard. so if you do buy it have it checked out for cracks on the pumpkin by the pinion and the over the pumpkin. i got my 4.11 7.5 posi that way for 350 from craigslist. but one that been run that hard might be on its last legs.

 

[krazykyle]

SOUNDS HOESED TO ME

 

[84cutspreme]

I feel like in my opinion a 7.5" drag rear is an oxymoron

 

[84GP455]

I feel like in my opinion a 7.5" drag rear is an oxymoron

Me too, i've broken 2 of them so far and am on my 3rd and my 455 is no drag car,,,,strong and fast, but no drag car. That's why i purchased a GN 8.5 rear end and will be installing it very soon.

 

[monte olrac]

I'm sure there's a reason they are putting a 9inch in instead of rebuilding the 7.5 with that said you wouldn't want to drive it on the street with that spool installed. so all in all you would be paying around 500+ dollars after you fix this rear. if found this site on beefing up a 7.5 for slicks, i would sugguest reading it to gain just a little more info to see if this rearend was really built for drag or if he just added a spool and c-clip eliminators and called it a day

http://www.thirdgen.org/beefinguprear

 

[patmckinneyracing]

Let me give another opinion on this one.

If you do get this rear end, which I think is one helluva deal, then yes take it to a shop and just have them inspect it. If there is nothing wrong with it and everything is in order, then you're ready to go. Only way your gonna end up spending 500$ is if the whole center unit needs to be replaced.

One reason the kid and his dad are probably going with a ford 9 inch is because they're probably going for more power and are making sure the entire drivetrain matches in power and durability. Most guys here have broken the 7.5 rear ends cause they simply neglected the unit themselves. It was probably the stock unit or just a swap in and they put in a good transmission and bigger motors, but neglected to take the 7.5 in for a check up. This is most often the case as it is expensive to have it checked while it's in the car, but most don't want to take the time to pull the rear end and take it to a shop.

Think of it this way, if you put in a new 455 motor in your car that is making plenty of power, which they do on most days anyway, and a solid transmission, but expect a 25-30 year old rear end to hold up to it, then you're an idiot.


I run a 86' monte ss rear end that is technically a 7.625, but identical nonetheless to the 7.5. I took it in once to have it checked and put in new seals and whatnot. About 4 months later, I chipped a pinion tooth cause I figured I would be cheap and use the stock ring and pinion. That was dumb on my part so I am speaking from experience here. I had the same guy put in a new Yukon ring and pinion gear and I've been driving it for 3 years now. That includes on the street, plenty of burnouts, racing, anything you can think of. The engine I'm running is a 400hp/450lb sbc 350.

If this father and son have drag raced this rear end with slicks and a 520hp motor, then I know they've had to use good quality parts that most guys here wouldn't bother putting in their 7.5's cause they feel it is a useless rear end. Hence why 8.5 rear ends are put on such a pedestial and people want stupid money for them.


Now I will agree a spool is something not made for street purposes but can be used for a good amount of time if your not using this as a daily driver.

 

[Minion1186]

They seem pretty serious about the racing part,and they ran wrinkle wall drag slicks and that car has won top eliminator class at the local strip so it does sound like a good buy.I'll take a good look at it before any deal is worked out,and when i get the gear installed by the shop i'll have them go over it just to make sure its good.I have about 402 horsepower/500 ft lb torque and i'll probably end up running drag radials so it should hold up to any abuse i throw at it.I'm also going to get a rearend girdle for it too.

 

[patmckinneyracing]

Sounds good to me as I'm not using a stud girdle myself but for safety sake why not. Have fun with it

 

[monte olrac]

Pat I would agree with you until this part:

And the only thing with it is,when it was in the 78 running the track,something happened with the ring and pinion and the gears that were in there got screwed up.This rear is partially assembled,just needs the new gears put into it.

Unless you are just using your car for the drag strip, that mini spool is not such a good idea for the street IMO.