Steel caps for 8.75" Mopars??? - Page 2

bill dedman · 06-09-2009, 10:31 AM

Thanks again for all the good advice, guys!

This setup has new, Moser, hi-strength axles, a new cone-type Sure Grip, a crush sleeve eliminator, a new driveshaft with 7290 u-joints and 11/16" axle/wheel studs.... You're right; I'm probably not gonna hurt it footbraking it, with this ol' 360, boost, or no.

I really do appreciate all the good advice!!!

Bill

Frank Bialas · 06-10-2009, 08:50 PM

Never enough money to do it right the first time, and than we do it right the second time.

If you think your alright than leave it alone, but remember this when it does break, now you also need a transmission fix and possibly a case too, the sprag doesn't like to be hit like that.

bill dedman · 06-11-2009, 12:10 AM

Your point is well-taken... I did put a crush-sleeve eliminator in it...

John Dinkel · 06-11-2009, 10:23 AM

My suggestion is too find a 742 case. I broke a 489 with my stocker.

Chuck Beach · 06-11-2009, 11:14 AM

John is right, find a 742 case. My 3500 lb. stocker has gone low 1.40 sixty foot with a 340. Last time I broke a rear end it was costly, it took out the trans and also damaged the thrust bearing in the motor. Contact Jim Bailey and have him process your gears and housing, it will help it last much longer.

Jim Wahl · 06-11-2009, 11:51 AM

John and Chuck are right. Use a 742 case from the get go. Every gear I ever broke in the SS car was in a 489 case. Jim

racerAL · 06-11-2009, 06:51 PM

Quote:

Originally Posted by Sean Haning

My 66 Belvedere with a 3500 converter, 440, slicks and 4.30 gears running low 7's never broke the 8 3/4. Who knows how old the center section was. I bought it used and was on stock axles for 3 years. So if its not your daily driver and you can't afford to beef up, just enjoy it until it needs it.

dittto......my 67 Satellite is set up almost identicle to this and i have had no problem with my stock 8 3/4. I'm running low 7's leaving off a trans brake ..i'm only running 4.10 gear though.

[/IMG]...well i tried for a half hr. trying to post a pic of my heap...lol..ive posted pics of it all over the net but for some reason i can't do it on this site...no biggie you get the idea. run that rear-end till it breaks...imo

bill dedman · 06-11-2009, 06:55 PM

Gotcha...
I have a 742 case on the floor in the garage. Got a 2.73 in it.... Bonneville, here I come!!!

No, I'll start buying parts for it as soon as there's some loose change around here; just spent each dime I could afford on a new driveshaft and that crush sleeve eliminator for the 489.

Now, lets see if this ol' 360 can do any damage to this much-maligned 489... LOL! New tires comin'...

Thanks, everyone, for all the good advice!!!

Bill
PS Al, mine's a 4.10, too...

ET6201 · 06-21-2009, 02:32 AM

Quote:

Originally Posted by bill dedman

Gotcha...
I have a 742 case on the floor in the garage. Got a 2.73 in it.... Bonneville, here I come!!!

No, I'll start buying parts for it as soon as there's some loose change around here; just spent each dime I could afford on a new driveshaft and that crush sleeve eliminator for the 489.

Now, lets see if this ol' 360 can do any damage to this much-maligned 489... LOL! New tires comin'...

Thanks, everyone, for all the good advice!!!

Bill
PS Al, mine's a 4.10, too...

I've found the tapered pinion is ok, as long as the crush sleeve is replaced with the spacer. The last time I checked, the only pro gears for the 8-3/4" were for the 1-3/4" 'stepped' pinion gears (4.44 and 4.86:1 ratios). That's the only reason I went away from the tapered pinion.

I think the weak link is the differential. I've had both late and early Suregrips ('68 & '69 340-S Barracudas) and burned up both. As the late style wears out, it deposits trash in your gear oil. The ring & pinion don't like that.

The early type (that uses clutches) lasts longer. Another advantage is that you can just throw a new clutch pack at it, and be on your way. A machinist friend (L.D. 'Dennis' Smythe) has rebuilt the late 'cone' style but it involves milling some material off the small end of the cones and installing taller springs.

Early style Suregrips are hard to find, and expensive when you find one. On the other hand, spools are easy to find, and VERY hard to break!

Bryan (aka By-Run)
"Be a good sport at the drags...
help your competitor O-U-T!"

Michael Pliska · 06-23-2009, 05:42 PM

Quote:

Originally Posted by ET6201

The last time I checked, the only pro gears for the 8-3/4" were for the 1-3/4" 'stepped' pinion gears (4.44 and 4.86:1 ratios). That's the only reason I went away from the tapered pinion.

Who still makes pro gears for the 8-3/4"? Is my recollection correct that the above mentioned 1-3/4" stepped pinion is for 742 case?

Thanks,

06-09-2009, 10:31 AM	#11
bill dedman VIP Member Join Date: Feb 2002 Location: Conway, AR Posts: 1,739 Likes: 0 Liked 6 Times in 4 Posts	Re: Steel caps for 8.75" Mopars??? Thanks again for all the good advice, guys! This setup has new, Moser, hi-strength axles, a new cone-type Sure Grip, a crush sleeve eliminator, a new driveshaft with 7290 u-joints and 11/16" axle/wheel studs.... You're right; I'm probably not gonna hurt it footbraking it, with this ol' 360, boost, or no. I really do appreciate all the good advice!!! Bill __________________ Bill

06-10-2009, 08:50 PM	#12
Frank Bialas Member Join Date: Sep 2007 Location: NJ Posts: 252 Likes: 6 Liked 23 Times in 13 Posts	Re: Steel caps for 8.75" Mopars??? Never enough money to do it right the first time, and than we do it right the second time. If you think your alright than leave it alone, but remember this when it does break, now you also need a transmission fix and possibly a case too, the sprag doesn't like to be hit like that. __________________ Frank Bialas 1570 STK

06-11-2009, 12:10 AM	#13
bill dedman VIP Member Join Date: Feb 2002 Location: Conway, AR Posts: 1,739 Likes: 0 Liked 6 Times in 4 Posts	Re: Steel caps for 8.75" Mopars??? Your point is well-taken... I did put a crush-sleeve eliminator in it... __________________ Bill

06-11-2009, 10:23 AM	#14
John Dinkel Senior Member Join Date: Nov 2005 Location: Pinckney, Michigan Posts: 507 Likes: 399 Liked 263 Times in 68 Posts	Re: Steel caps for 8.75" Mopars??? My suggestion is too find a 742 case. I broke a 489 with my stocker. __________________ John Dinkel 3295 STK

06-11-2009, 11:14 AM	#15
Chuck Beach Senior Member Join Date: Jun 2006 Location: Delaware, Ohio Posts: 664 Likes: 12 Liked 58 Times in 13 Posts	Re: Steel caps for 8.75" Mopars??? John is right, find a 742 case. My 3500 lb. stocker has gone low 1.40 sixty foot with a 340. Last time I broke a rear end it was costly, it took out the trans and also damaged the thrust bearing in the motor. Contact Jim Bailey and have him process your gears and housing, it will help it last much longer. __________________ Chuck Beach 3340 STK

06-11-2009, 11:51 AM	#16
Jim Wahl Veteran Member Join Date: Jan 2002 Location: Central Florida Posts: 5,843 Likes: 666 Liked 683 Times in 129 Posts	Re: Steel caps for 8.75" Mopars??? John and Chuck are right. Use a 742 case from the get go. Every gear I ever broke in the SS car was in a 489 case. Jim __________________ Jim Wahl....NHRA #2239 S/SS - IHRA # 8 Stock, D2 Stock Champion (forever I guess) 2019 Baby Gators Stock Champion 2009 D2 National Open Stock Champion 1981 D2 West Palm Beach LDRS SS Runner Up Past President, Southern Stock / Super Stock Association.

06-11-2009, 06:55 PM	#18
bill dedman VIP Member Join Date: Feb 2002 Location: Conway, AR Posts: 1,739 Likes: 0 Liked 6 Times in 4 Posts	Re: Steel caps for 8.75" Mopars??? Gotcha... I have a 742 case on the floor in the garage. Got a 2.73 in it.... Bonneville, here I come!!! No, I'll start buying parts for it as soon as there's some loose change around here; just spent each dime I could afford on a new driveshaft and that crush sleeve eliminator for the 489. Now, lets see if this ol' 360 can do any damage to this much-maligned 489... LOL! New tires comin'... Thanks, everyone, for all the good advice!!! Bill PS Al, mine's a 4.10, too... __________________ Bill