Sure Grip rears... Good for the occasional drag racers?

[Glennster]

 I want to go to a 3.91 rear gear to do a little drag racing. I'm going to buy a chunk/pig rather than putting new gears on my 742 pig. I spoke to Cooter for quite a while (great guy) but still don't quite understand how much the Sure Grip will lock up both rear tires at the old drag strip.
 I've got about 460 HP and plan to buy some drag radials that will fit under my stock fenders.
Does the 741 Sure Grip lock up like a 489 and a 742? Are all the Sure Grips the same from a lock up standpoint?

[70_Hemi_Cuda]

I would think a suregrip would be just fine for occasional drag racing. I ran a 489 case with 4.10 and a suregrip and I never had issues with uneven traction, it would lay down 40-50 feet of rubber and be exactly even.

[Moparal]

Did cooter say it was a cone or a powerlock?  These two types fit all the number cariers. Also, 490 hp isn't gonna hurt either unit, spinning one in the water and leaving the other on dry ground will burn them up tho. Usually a 741 had a power lock since it's the older unit and is rebuildable.  741 is the smallest pinion bearing size, but will easly do the job for your combo

[Glennster]

Cooter has the 741 cone type......I'm not sure what a bargain is for a 741, he wants $400.
 It sounds like I'm safe with 460 HP and an auto trans running a 741. I was not sure if one type of Sure Grip would lock up both tires real good and the other would not.......
 

[Chryco Psycho]

if they are in good condition both types will lock up with power

[Cooter]

Basically, I stated Nothing will LOCK the rear tires when say one tire is in the mud and one on asphalt...ANY Sure Grip will always apply the power to the wheel with the less grip and therefore ...Spin that wheel....The ONLY rear is a spool that will pull BOTH rear wheels even when one is "Unloaded"...


It would depend on the rear suspension set up as to how well ANY Sure Grip hooks BOTH wheels evenly..Now, when your talking Spinning, well as long as BOTH rear wheels are "Unloaded" the same then, therefore both will spin evenly...I also stated that there are folks out there that will sell a "489" or a "742" Clutch style chunk for $50.00, but I'm of the opinion that while stranger things have happen, I wouldn't count on gettin' that "Good" chunk for that deal...If this one isn't worth $400.00, then it'll sit right here  until there's no other option cept paying Randy's $1500.00 for a new "489"/"742" chunk...
If strength is the issue, then there's always a Dana 60 I got laying around...

However, a "741" worked fine in my 1.89 60 Ft., 505 Stroker Dart, ran high 6's 8th mile for over 14 years...You break it with a small block stroker and someone's doing something other than launching with an automatic and a 2200 stall....For everything Moroso puts out, there's Somebody that will find a way to break it, and blame the quality...Yes, I wouldn't trust, or sell this chunk to someone with a 4-spd..... IMO, the "741" Chunk got the same treatment as the '73-'78 440 blocks..

[Glennster]

Cooter,
 THANKS for clearing that up! I appreciate your time!