Understeer all day every day

[e30_302]

Put a zip tie around the shock shaft and see how far it gets pushed up.

How do the front tires appear to be wearing? Signs of rolling over?

If the front is significantly stiffer than the rear, it'll be unbalanced. A McP strut car needs a lot of roll stiffness to keep the camber curve in check, however. Work on optimizing the front before you turn to adjusting on the rear to get the balance you want.

[FredK]

6kg F / 8kg R corresponds to 336 lb F / 448 lb R. With a 21mm front bar (hopefully not a 12), the car should have OK roll stiffness, i.e. not feel like it's plowing on corner entry.

Even with the stock suspension, an M42 car rotates very easily, and is superbly balanced.

Are there any alignment settings available?

[ForcedFirebird]

6kg F / 8kg R corresponds to 336 lb F / 448 lb R. With a 21mm front bar (hopefully not a 12), the car should have OK roll stiffness, i.e. not feel like it's plowing on corner entry.

Even with the stock suspension, an M42 car rotates very easily, and is superbly balanced.

Are there any alignment settings available?

The ratio for F/R is a little biased. Spec e30 with H&R are running at 315f/570r (5.6kgf/10.1kgr), and people tend to still complain of pushing. The higher the front spring rate in in relation to the rear, the more the car will want to push. I had stock sways on my e30 during HPDE with 450f/700r and had to disconnect the rear sway to balance it back out.

OP, cheap/easy way to see if your rear springs are too stiff in relation to the front is unbolt your rear sway links. Can do it at the track for back to back comparison.

Also if you have rear adjusters you can toe the rear out to compensate,b but it's not the correct solution.

[Emre]

I don't want to be "that guy," but you also have to consider driving style.

I've had many students who induce understeer into corners by coming off the brakes too early and turning in too sharply. It can feel fast/exciting to "toss the car into a corner," but it can sometimes turn even a well-balanced car into an understeering pig.

Not saying that's what you're doing ... but it's something to consider.

[econti]

Put a zip tie around the shock shaft and see how far it gets pushed up.

How do the front tires appear to be wearing? Signs of rolling over?

If the front is significantly stiffer than the rear, it'll be unbalanced. A McP strut car needs a lot of roll stiffness to keep the camber curve in check, however. Work on optimizing the front before you turn to adjusting on the rear to get the balance you want.

I'll give the cable tie thing a go and see what happens.

Fronts seem to be wearing well. Fairly even as far as I can tell, no feathering and minimal camber wear.

6kg F / 8kg R corresponds to 336 lb F / 448 lb R. With a 21mm front bar (hopefully not a 12), the car should have OK roll stiffness, i.e. not feel like it's plowing on corner entry.

Even with the stock suspension, an M42 car rotates very easily, and is superbly balanced.

Are there any alignment settings available?

Like, it's very good, feels really nice and goes stupid fast, but I'm interested in reducing understeer to go even faster ;D

Last alignment was -2.6 camber +0.05 toe +9 caster

The ratio for F/R is a little biased. Spec e30 with H&R are running at 315f/570r (5.6kgf/10.1kgr), and people tend to still complain of pushing. The higher the front spring rate in in relation to the rear, the more the car will want to push. I had stock sways on my e30 during HPDE with 450f/700r and had to disconnect the rear sway to balance it back out.

OP, cheap/easy way to see if your rear springs are too stiff in relation to the front is unbolt your rear sway links. Can do it at the track for back to back comparison.

Also if you have rear adjusters you can toe the rear out to compensate,b but it's not the correct solution.

I'll drop the sway and see what happens.
No rear adjusters

I don't want to be "that guy," but you also have to consider driving style.

I've had many students who induce understeer into corners by coming off the brakes too early and turning in too sharply. It can feel fast/exciting to "toss the car into a corner," but it can sometimes turn even a well-balanced car into an understeering pig.

Not saying that's what you're doing ... but it's something to consider.

You can be "that guy" all you like, I freely accept I'm not a well trained driver. Decent, but not trained professionally.

I have been messing around with my driving, and it doesn't seem to make much of a difference. The understeer happens regardless of whether I'm on power or under brakes.

[ak-]

Is it bouncing and understeering at the same time when hard cornering, just pushes madly?

[econti]

Just pushes. Doesn't matter if I'm under brakes or on power. Always understeers well before oversteer, even if I'm trying to slide it.
Granted, it is a M42, but still...
Even if I come hard in to a downhill corner under brakes with the back totally unloaded, it'll just four wheel slide

[Emre]

You can be "that guy" all you like, I freely accept I'm not a well trained driver. Decent, but not trained professionally.

I have been messing around with my driving, and it doesn't seem to make much of a difference. The understeer happens regardless of whether I'm on power or under brakes.

Your alignment settings look right. The 318is should have excellent turn-in response (I drove one from 1991 until I sold it in 2010). So, I'm thinking you may be turning-in too sharply, which will induce understeer in any car.

The other thing to keep in mind is the condition of the rear diff. The small-case LSD in the 318is wears out pretty quickly (in my experience). If your diff isn't locking up tightly anymore, that can make the car feel more understeery.

[ForcedFirebird]

The other thing to keep in mind is the condition of the rear diff. The small-case LSD in the 318is wears out pretty quickly (in my experience). If your diff isn't locking up tightly anymore, that can make the car feel more understeery.

Typically the higher the lock, the more the car will push as a result of the wheels being less "independent". The inner wheel will want to travel at the same rate as the outer wheel, making the car want to go straight. This is very severe in welded diffs.

[Emre]

The M42 doesn't make any power and the stock diff hardly locks up at all. The car underteers much less when the diff is working well (rotates better). We're not talking about a 750 hp muscle car with Detroit locker.

[markseven]

As FredK stated, these cars handle well stock, great on aftermarket suspensions, with a tendency to oversteer as you were expecting. IMO adding camber as a solution is a bandaid considering the level of understeer you have described.

Corner balance with you in the car. That's where I would start.

[kronus]

16x8 wheels, 205/50 Federal 595EVOs

The tyres aren't track spec but they're pretty decent albeit a year old or so. They've been through a lot of heat cycles but it's always tended into understeer, just now more so than ever.

you understeered enough that the outsides of your front tires are totally toast

[kronus]

also 205 on 16x8 is enough stretch that the tires aren't going to fold over at all during turning, which decreases your contact patch significantly and always puts it on the same roasted outside bit of your tire

also, not a lot of weight upfront on stiff springs and uprated sways -> car skates across line instead of digging in and gripping

(assuming by 12mm sway you do mean 21mm sway)

[markseven]

also 205 on 16x8 is enough stretch that the tires aren't going to fold over at all during turning, which decreases your contact patch significantly and always puts it on the same roasted outside bit of your tire

also, not a lot of weight upfront on stiff springs and uprated sways -> car skates across line instead of digging in and gripping

(assuming by 12mm sway you do mean 21mm sway)

22mm?

[kronus]

22mm?

op says 12, that's not a front bar size ever offered on e30s