Good golly I'm understeering.

Ok, let's get the various reasons on the table: 1) recently swapped to a ford 8.8 with a trac lok lsd. 2) I haven't yet fitted a rear sway bar back on the car because of the swap. 3) my front tires are made of cheese 4) I purposely overcook the "test" corner (verifying the car at its limits.)

The lack of a rear bar must contribute. The tires suck, but it's the same scenario out back. The real question here is the LSD. It should produce understeer on lift right? So even if I put my rear bar back on, it'll likely still understeer. Meaning I need to adjust my driving habits and maybe trail brake a little more.

The corner in question (abandoned development in an undisclosed area of the world) is a steep downhill into a quick 90° right hander that flattens out at the apex.

Temporarily drop the front bar and see if that helps.

A clutch type LSD will usually cause a little bit of understeer (both power and off, but more so with power on). However, once you get the rear end to start to rotate, it'll be more likely to want to get loose completely.

A rear bar or more rear spring may help with the issue. It might also be solvable with weight transfer / driving technique or an alignment change to get more grip up front. More caster might help by adding some front end grip and getting a little weight off the inside rear when you turn in.

So, did it understeer with cheesy tires before the rear end swap?

Don't make any decisions until after you've changed the tires.

Your chosen testing corner is just about guaranteed to exaggerate understeer. And that being said, the number of cars that won't benefit from more negative camber up front. can be counted on one hand.

The thread title reminded me of this:

https://www.youtube.com/embed/RH4wM5bWDPE

From what I understand the Trac-Lok is a 1.5way LSD, so it will lock up when coasting, and this will cause the rear axle to resist rotation. This will contribute to understeer. But your missing rear sway bar is probably a far bigger issue.

In reply to trucke:

Eh.... Kinda. If I went into the same corner in neutral and no added dive it would understeer. If I trail braked, it would rotate. But that was all pre swap.

Stefan (Not Bruce) wrote: Temporarily drop the front bar and see if that helps.

That's my next step. I want to verify if it's bar related. Side question: where to get a cheap sway bar made?

Duke wrote: Your chosen testing corner is just about *guaranteed* to exaggerate understeer. And that being said, the number of cars that *won't* benefit from more negative camber up front. can be counted on one hand.

I'm guessing the test corner loads the front outside tire more than usual? More Camber can be had, but it's a weekend car, and I'm not wanting to buy tires too often. (I know, I know... Wth is wrong with me)

In reply to Trackmouse:

Have you seen the posts about using a spare torsion bar and end caps to build your own adjustable sway bar?

With no bars, you'll need to turn in earlier to get the car to set and orient to the apex. As long as you have enough camber and caster it should have plenty of grip up to the limit of the tires.

jstein77 wrote: Don't make any decisions until after you've changed the tires.

This.

It's easy to presume that because all-4 tires equally lack grip that the balance of the car won't change with better rubber, but it's usually the exact opposite - and to very extreme differences typically.

Stefan (Not Bruce) wrote: In reply to Trackmouse: Have you seen the posts about using a spare torsion bar and end caps to build your own adjustable sway bar? With no bars, you'll need to turn in earlier to get the car to set and orient to the apex. As long as you have enough camber and caster it should have plenty of grip up to the limit of the tires.

Links to post? This sounds great!

In reply to Dusterbd13:

To the Googles! Because I didn't bookmark it and I don't remember where I saw it now.

Basically the deal was to use a VW Bug torsion bar (or similar like a Super Beetle, 911, 924, 944 or 968) and cut the splined ends off a couple of donor suspension arms (or torsion carriers) and weld them to arms of your own design. Get some bushings of the proper diameter and hangers to mount them to the car, fab up some linkage to the arms and get after it.

The trick is ensuring the splined ends are welded to ensure the arms are even to avoid trying to adjust out an uneven set of arms with the linkage.

Stefan (Not Bruce) wrote: In reply to Dusterbd13: To the Googles! Because I didn't bookmark it and I don't remember where I saw it now. Basically the deal was to use a VW Bug torsion bar (or similar like a Super Beetle, 911, 924, 944 or 968) and cut the splined ends off a couple of donor suspension arms (or torsion carriers) and weld them to arms of your own design. Get some bushings of the proper diameter and hangers to mount them to the car, fab up some linkage to the arms and get after it. The trick is ensuring the splined ends are welded to ensure the arms are even to avoid trying to adjust out an uneven set of arms with the linkage.

I'm pretty sure Loosecannon did that with a 911SC on the E/Mod MG GT B.

In reply to NickD:

Very, very likely. Thank you.

I'll have to search for a link. How can you control the spring rate of a torsion bar? Isn't it set from the factory?

Trackmouse wrote:

Duke wrote: Your chosen testing corner is just about *guaranteed* to exaggerate understeer. And that being said, the number of cars that *won't* benefit from more negative camber up front. can be counted on one hand.

I'm guessing the test corner loads the front outside tire more than usual? More Camber can be had, but it's a weekend car, and I'm not wanting to buy tires too often. (I know, I know... Wth is wrong with me)

Yes, indeedy:

• Downhill under braking adds forward weight transfer
• Paving is (probably) off-camber through the turn
• It's a right, so weight bias is against you

Regarding camber, I've never found static negative camber to cause wear problems in front unless it is extreme due to alterations or damage. Usually it helps with outside shoulder wear on a street car. Toe is what causes excessive wear in my experience.

In reply to Trackmouse:

Same way you would adjust a regular sway bar. You change the diameter. You can't change the spring rate any other way. You can adjust the effective rate to some extent, but that's not the same thing.

Using an off the shelf torsion bar from a popular vehicle(s) means that you can change the bar out for different diameters much more easily.

For fine tuning you can do the same thing as you would with a standard sway bar, change the lengths of the lever arms (generally through a sliding clamp or different mounting holes on the arms) Much the same way one would adjust shocks or tire pressures.

Duke wrote:

Trackmouse wrote:

Duke wrote: Your chosen testing corner is just about *guaranteed* to exaggerate understeer. And that being said, the number of cars that *won't* benefit from more negative camber up front. can be counted on one hand.

I'm guessing the test corner loads the front outside tire more than usual? More Camber can be had, but it's a weekend car, and I'm not wanting to buy tires too often. (I know, I know... Wth is wrong with me)

Yes, indeedy: * Downhill under braking adds forward weight transfer * Paving is (probably) off-camber through the turn * It's a right, so weight bias is against you Regarding camber, I've *never* found static negative camber to cause wear problems in front unless it is extreme due to alterations or damage. Usually it *helps* with outside shoulder wear on a street car. Toe is what causes excessive wear in my experience.

+1^ Especially true on the tire wear if you fail to rotate your tires every other oil change like a good car owner.

You also can change the bar rate by altering the length of the arms.

Stefan (Not Bruce) wrote:

Duke wrote:

Trackmouse wrote:

Duke wrote: Your chosen testing corner is just about *guaranteed* to exaggerate understeer. And that being said, the number of cars that *won't* benefit from more negative camber up front. can be counted on one hand.

I'm guessing the test corner loads the front outside tire more than usual? More Camber can be had, but it's a weekend car, and I'm not wanting to buy tires too often. (I know, I know... Wth is wrong with me)

Yes, indeedy: * Downhill under braking adds forward weight transfer * Paving is (probably) off-camber through the turn * It's a right, so weight bias is against you Regarding camber, I've *never* found static negative camber to cause wear problems in front unless it is extreme due to alterations or damage. Usually it *helps* with outside shoulder wear on a street car. Toe is what causes excessive wear in my experience.

+1^ Especially true on the tire wear if you fail to rotate your tires every other oil change like a good car owner.

Can't change tires. Rear is five lug, 4 lug in front. (I could swap tired to the wheels, but that's getting expensive.)

In reply to Trackmouse:

Walmart will swap and balance tires for $13/rim if they're off the car fwiw.