Mopar 8 3/4 users question for ya

Scatpacktom · 11-14-2009, 09:43 AM

How many passes are your 8 3/4s good for? What are your 60s and what kind of special treatment are you spending money on?

I'm building a mid 11 second automatic stocker that will weigh 3600 or so and to be honest I'd like to make it as user friendly as I can. I own all kinds of 8 3/4s and Danas. Parts is not the problem.

I guess my real question is,if you could go back and start over would you take the 60 lb weight hit and just stick a Dana in your car? Or is the 8 3/4 a "real" advantage?

Thanks, Tom

Bob Pagano · 11-14-2009, 10:41 AM

Put the dana in and forget about it, it will be cheaper in the long run.

gmonde · 11-14-2009, 01:04 PM

i have two center sections that i swap with and i have over 100 pases on the 4.56 ,50 passes on the 4.89 both are 489 cases ,one after market nodular iron ,one stock case with mark willaim caps ,,car weighs 3690 ,,1.540 60' so far so good gmonde

Duster 7695 · 11-14-2009, 03:39 PM

I have 250 passes on mine. It is a factory 489 case with Mark Williams caps and Strange 35 spline spool. I just went from 4.56 to 4.86 gears. The old gears still look new. I have not done anything to the Richmond gears that I run. My car is a high 11 second car that weighs 3300 lbs. I foot brake it. If you are going to use a tranny brake or have a manual tranny I suggest you put the Dana in it. There are a lot of 10 second and 11 second stock eliminator Mopars that are using the 8 3/4.

bob gonier · 11-14-2009, 08:32 PM

I run one in my 69 Firebird LOL.................................. I usually get between 350-500 passes on a ring and pinion. My car weighs 3550lbs and goes low 10's @ 135mph. Its got a 1.76 glide and 4.10's w/28" tire. It goes low 1.50's with the glide and has seen 1.36 with a turbo trans. I see no need for a Dana in your application. Just use the "better" 742 case and you'll be fine.

jmo.........

bob

Michael Pliska · 11-16-2009, 03:14 PM

I've got one in my S/G car, but it has pro gears (the special 4.75 ratio ones). When I bought the rolling chassis it had 4.89 pro gears, and they lasted a couple of seasons on the trans brake (around 1.32 60' times, car weighed around 2500). After they broke I ended up using "street" gears, and they would last about 300 passes or so before breaking. I think I broke 3 sets, and no two sets broke the same way. Nowadays the car runs 1.29-1.30 60' times, weighs about 2400, and has been working well with the 4.75's in it.

Regards,

Philip Saran · 11-16-2009, 03:17 PM

Can I ask how many of you use a brace welded onto the back side
of your 8-3/4 housing?

Tom keedle · 11-16-2009, 07:20 PM

Quote:

Originally Posted by Philip Saran

Can I ask how many of you use a brace welded onto the back side
of your 8-3/4 housing?

i'm thinking about it.....

gmonde · 11-16-2009, 07:48 PM

any car with a stick or a trans break should have it ,,a foot break car should be ok but there are some foot break cars with some low 60' that mite need one,,i do not have one ,but if i go to the stick it will get one

gmonde

Scatpacktom · 11-17-2009, 08:32 PM

Thanks for the replies guys.

11-14-2009, 09:43 AM	#1
Scatpacktom Junior Member Join Date: Jul 2005 Location: Phila, PA Posts: 11 Likes: 0 Liked 0 Times in 0 Posts	Mopar 8 3/4 users question for ya How many passes are your 8 3/4s good for? What are your 60s and what kind of special treatment are you spending money on? I'm building a mid 11 second automatic stocker that will weigh 3600 or so and to be honest I'd like to make it as user friendly as I can. I own all kinds of 8 3/4s and Danas. Parts is not the problem. I guess my real question is,if you could go back and start over would you take the 60 lb weight hit and just stick a Dana in your car? Or is the 8 3/4 a "real" advantage? Thanks, Tom

11-14-2009, 10:41 AM	#2
Bob Pagano VIP Member Join Date: Jun 2002 Location: New Holland, PA Mooresville,NC Posts: 1,163 Likes: 232 Liked 16 Times in 11 Posts	Re: Mopar 8 3/4 users question for ya Put the dana in and forget about it, it will be cheaper in the long run. __________________ Bob Pagano A/SA

11-14-2009, 01:04 PM	#3
gmonde Senior Member Join Date: Nov 2007 Posts: 615 Likes: 56 Liked 165 Times in 59 Posts	Re: Mopar 8 3/4 users question for ya i have two center sections that i swap with and i have over 100 pases on the 4.56 ,50 passes on the 4.89 both are 489 cases ,one after market nodular iron ,one stock case with mark willaim caps ,,car weighs 3690 ,,1.540 60' so far so good gmonde

11-14-2009, 03:39 PM	#4
Duster 7695 Member Join Date: Dec 2008 Posts: 140 Likes: 1 Liked 8 Times in 6 Posts	Re: Mopar 8 3/4 users question for ya I have 250 passes on mine. It is a factory 489 case with Mark Williams caps and Strange 35 spline spool. I just went from 4.56 to 4.86 gears. The old gears still look new. I have not done anything to the Richmond gears that I run. My car is a high 11 second car that weighs 3300 lbs. I foot brake it. If you are going to use a tranny brake or have a manual tranny I suggest you put the Dana in it. There are a lot of 10 second and 11 second stock eliminator Mopars that are using the 8 3/4.

11-14-2009, 08:32 PM	#5
bob gonier Junior Member Join Date: Dec 2005 Location: monroe twp nj Posts: 66 Likes: 0 Liked 1 Time in 1 Post	Re: Mopar 8 3/4 users question for ya I run one in my 69 Firebird LOL.................................. I usually get between 350-500 passes on a ring and pinion. My car weighs 3550lbs and goes low 10's @ 135mph. Its got a 1.76 glide and 4.10's w/28" tire. It goes low 1.50's with the glide and has seen 1.36 with a turbo trans. I see no need for a Dana in your application. Just use the "better" 742 case and you'll be fine. jmo......... bob

11-16-2009, 03:14 PM	#6
Michael Pliska Member Join Date: Oct 2008 Location: Happy Valley, OR Posts: 260 Likes: 0 Liked 0 Times in 0 Posts	Re: Mopar 8 3/4 users question for ya I've got one in my S/G car, but it has pro gears (the special 4.75 ratio ones). When I bought the rolling chassis it had 4.89 pro gears, and they lasted a couple of seasons on the trans brake (around 1.32 60' times, car weighed around 2500). After they broke I ended up using "street" gears, and they would last about 300 passes or so before breaking. I think I broke 3 sets, and no two sets broke the same way. Nowadays the car runs 1.29-1.30 60' times, weighs about 2400, and has been working well with the 4.75's in it. Regards, __________________ Michael Pliska 643 S/G

11-16-2009, 03:17 PM	#7
Philip Saran Senior Member Join Date: Oct 2006 Location: Parker, CO. Posts: 727 Likes: 160 Liked 14 Times in 11 Posts	Re: Mopar 8 3/4 users question for ya Can I ask how many of you use a brace welded onto the back side of your 8-3/4 housing? __________________ Phil Saran Parker, Colorado

11-16-2009, 07:48 PM	#9
gmonde Senior Member Join Date: Nov 2007 Posts: 615 Likes: 56 Liked 165 Times in 59 Posts	Re: Mopar 8 3/4 users question for ya any car with a stick or a trans break should have it ,,a foot break car should be ok but there are some foot break cars with some low 60' that mite need one,,i do not have one ,but if i go to the stick it will get one gmonde

11-17-2009, 08:32 PM	#10
Scatpacktom Junior Member Join Date: Jul 2005 Location: Phila, PA Posts: 11 Likes: 0 Liked 0 Times in 0 Posts	Re: Mopar 8 3/4 users question for ya Thanks for the replies guys.