Diff Cover Drain

[Supercharged111]

In 2015 my car dynoed 70hp low. Turns out I'd lost a rod bearing the last race of the year prior. I forgot how weird the car had felt the last lap or 2 and how I'd just cruised there because we were really spread out by that point. I grabbed a crank off of CL and had it polished, pistons and rods used off of Fleabay, new bearings and gaskets, honed in my garage, all in for about $800. That motor is still in and healthy, has been good and made good numbers. It's getting replaced by an LS. While the rest of the crap is an asspain to hunt down cheap, the motor itself was $220 from the pull and pay for an aluminum LM4. Gotta find another for a spare. 170k and I'm not doing anything to the bottom end. Got a late LS1 cam for free fiddy to pop in there and that's it. I don't believe in machine shop engines for these cars when stock seems to last just fine.

[Pranav]

Leave the ls1 cam alone.

An lm4/lm7 as is with some work on intake exhaust restriction is all you need.

If you throw the ls cam in there you may have trouble getting the torque you need after choking the power down to get under the HP limit.

[Al Fernandez]

I'm pretty confident the reason for Gm having worse rear end reliability than the Fords is all due to axle hop and no diff cover is going to fix that. I've never blown a rear end, and only rebuilt mine recently because the 13 or so yr old T2R was feeling like it wasn't working well any more.

[liquidroam]

a little late to the party on this one.... but what an entertaining read. A bit off the wall at points but good entertainment value! Ya mine was in the early days before I did any sort of mechanical prep to the car and was running HPDE. Do much more these days but Hallett will show that my experience is about the same. Looking forward to getting that part of my racing career behind me. Well to the extent that is reasonable.

[Pranav]

I'm pretty confident the reason for Gm having worse rear end reliability than the Fords is all due to axle hop and no diff cover is going to fix that. I've never blown a rear end, and only rebuilt mine recently because the 13 or so yr old T2R was feeling like it wasn't working well any more.

So what can we do about eliminating axle hop?

If there's one major platform disparity, it's that fact that F-bodies have to drive and brake bias around rear axle hop while the ford guys can actually use their rear brakes and go fully aggressive with brake compound.

If I understand correctly it can be as simple as converting the nose end of the torque arm to be a sliding type instead if a fixed bushing with no other geometry changes.

[Sook]

So what can we do about eliminating axle hop?

If there's one major platform disparity, it's that fact that F-bodies have to drive and brake bias around rear axle hop while the ford guys can actually use their rear brakes and go fully aggressive with brake compound.

If I understand correctly it can be as simple as converting the nose end of the torque arm to be a sliding type instead if a fixed bushing with no other geometry changes.

As an alternative, we could allow torque arms on mustangs to induce wheel hop.

[Fbody383]

6.33.7 Suspension bushing material is unrestricted.

Does this include the torque arm bushing?

[RichardP]

So what can we do about eliminating axle hop?

If there's one major platform disparity, it's that fact that F-bodies have to drive and brake bias around rear axle hop while the ford guys can actually use their rear brakes and go fully aggressive with brake compound.

If I understand correctly it can be as simple as converting the nose end of the torque arm to be a sliding type instead if a fixed bushing with no other geometry changes.

Apparently one of the best fixes for axle hop is a stiffer, aftermarket torque arm that doesn't attach to the transmission. Other than that, you are playing with spring/damping/tire pressures to make the car less likely to hop. When that inevitably doesn't work, you crank the rear bias to almost turn the rear brakes off...


Richard P.

[Pranav]

Apparently one of the best fixes for axle hop is a stiffer, aftermarket torque arm that doesn't attach to the transmission. Other than that, you are playing with spring/damping/tire pressures to make the car less likely to hop. When that inevitably doesn't work, you crank the rear bias to almost turn the rear brakes off...


Richard P.

Fixed that for you. I know the the Mustangs have a shitty rear suspension, but are at least able to run ideal rear brake compounds and spring rates. We, not so much...

[Pranav]

Gary's street 3rd gen has a nice sliding type bushing that uses an otherwise stock torque arm setup, will see if he can send pics.

It involved modifying a stock torque arm.