8 3/4 Center Section H.P Ratings / Aluminum

[moparcrazy]

How Many of you guys are still running your 8 3/4 at the track, or Dana or Hate to say it 9" or After market set up's ?? I'm really wanting to keep my 8 3/4, its lite and easy to change center sections for track or street use, Mark Williams offer's Pro Gears for the 8 3/4 plus Shot penning and other service's not available to the mopar Guys before, I've also considered the Aluminum 8 3/4 Center section just like the Ford guy's have had for years !!

 

[1967coronet440]

When I decided I was going to be making some good power I went with a strange s60

 

[Fran Blacker]

Thought pro gears are to soft for the street, or is it just name?

 

[1967coronet440]

Thought pro gears are to soft for the street, or is it just name?

Ya Cass told me if it has any street time to avoid the pro gears.

 

[6PKRTSE]

I ran 4:88 Pro gears in my old 69 Pro Street Charger for 5-6 years with a lot of street miles & many 1/4 mile passes with no issues, then sold the car.

 

[PurpleBeeper]

I know you can get a back brace welded onto the 8-3/4's and I've been running one for years BUT I'm not running slicks/hardened axles. "Word on the street" is don't run an 8-3/4" with slicks with a b-body....maybe OK with an A-body or REALLY light car.... or so I've heard.

 

[Cranky]

The 9" has that extra little bearing behind the pinion and that seems to help but if you do not use all the 'good' parts like the nodular iron case etc, it's not much better if any than the 8 3/4 is. The killer isn't so much as housing flex but the pinion deflecting and that's what kills the gears. Also, the lack of the stronger parts like the Pro gears over the years is why you see so many gear failures. They were available many years ago but since there wasn't a large call for them, most places that made gears simply quit making them. The aluminum case was also available many years ago too. And if you set up your own gears and run a Dana, I can tell you that it goes pretty fast once you get two or three sets made up. Just keep your shims with those gears when you pull them out and the next time you want to use them, it's a slam dunk.

 

[Mike Gaines]

Give it up on the 8 3/4 and spend the money ONE TIME for a DANA.
The Dana rear end is like having the 4 bolt mains on your block.
Sooner or later you will blow the 8 3/4 and it will take the tranny with it.

 

[1967coronet440]

Give it up on the 8 3/4 and spend the money ONE TIME for a DANA.
The Dana rear end is like having the 4 bolt mains on your block.
Sooner or later you will blow the 8 3/4 and it will take the tranny with it.

Happened to me already with a 383 when I first finished my car, launched it with my et streets on the back, rearend blew up driveshaft wen through the floor and took my brand new 727 out with it, I don’t plan on having that happen again.

 

[moparcrazy]

Thought pro gears are to soft for the street, or is it just name?

Fran blacker pro gears are not for the street, but I do have friends who run them on the street, my plan is to have two deferent center sections, one with 4.88 P.G and the other 4.10 for the street None Pro~Gear.

 

[Fran Blacker]

Fran blacker pro gears are not for the street, but I do have friends who run them on the street, my plan is to have two deferent center sections, one with 4.88 P.G and the other 4.10 for the street None Pro~Gear.

Ah So, I see.

 

[Mike Gaines]

My brother in law has a pro-street 55 chevy...big motor...he bought and installed a Gear Vendors Over-Under Drive. He has 4.88 gears for drags and then kicks in the overdrive that cut's it back to around 3.23 for highway and street use. It's about 3 grand, I think.

 

[moparcrazy]

My brother in law has a pro-street 55 chevy...big motor...he bought and installed a Gear Vendors Over-Under Drive. He has 4.88 gears for drags and then kicks in the overdrive that cut's it back to around 3.23 for highway and street use. It's about 3 grand, I think.

Yes Sir I also have the Gear Vendor and Love it !!

 

[1967coronet440]

Come on man, I KNOW you already got the mega block and trans, bit the bullet and get yourself a dana.

 

[moparcrazy]

Check out his Tire RPM Calculator
https://www.reillymotorsports.com/speed-tire-rpm-calculator.html

 

[moparcrazy]

Come on man, I KNOW you already got the mega block and trans, bit the bullet and get yourself a dana.

LMAO just trying to do what they say cant be Done !!

 

[LemonWedge]

Putting the money into a Dana is probably the solid choice. With that said; while I only make somewhere around 525 hp, I do throw 3800+ lbs at my 8-3/4 on slicks, at the track, and often. It’s backbraced, runs a 742 pig with steel caps, Richmond 4.10’s on a spool and 35-spline DrD axles. Will I break it (again) someday?.... Yeah, probably. But it’s working for me currently.

My guess is that the MP aluminum center section turns the 8-3/4 into a pretty reliable item, but it’s WAY too expensive as far as I’m concerned. If MP wonders why they don’t sell many, they can look no further that the full grand asking price.

 

[451Mopar]

I looked at upgrading my 8-3/4", but it would have needed everything. Axles, spool, gears, bearings, back brace, and yoke. The cost added up close to what the Strange S60 was.
For drag racing I like using the RedLine Shock Proof gear oil. I think the gear oil helped keep the 8-3/4" alive until it was swapped.

 

[dvw]

8 3/4 will live in a lot of applications. Once a 3300 lb and up car gets to 11.0 it's on borrowed time. Junkyard Dana's are cheaper than aftermarlet 8 3/4 parts upgrades. You can transfer your housing ends, axles, brakes to a truck Dana with a little thought. We have even run the Junkyard gears in 800hp+ aplications. A spool , a $200 gear (if needed), either donor parts from your 8 3/4 (or axles and housing ends), a little welding and your ready to go. My street gears survived 450 passes 900hp@3350lbs before they became noisy. I bought another set of $200 street gears from Dr Diff and I was back in business .
Doug

 

[2quick]

I'm running an 8 3/4 I actually bought from Mike Gaines. When I bought it I wasn't planning on making the power I am now but I think I've given it a fighting chance. Is a S60 in the future? maybe but for now the 8 3/4 is still in there.

Narrowed 8"
Moser axles
4.10 gears
Detroit Locker
Back and Top Braced
Willwood disc's