Handling not so good after m52 swap...

[Codym42]

I've put around 2500 miles on my m52 swap and it feels like the balance of the car has been lost. I used to be able to drive the car hard on twisty roads with no issues, but now it feels like the rear end is about to come unglued. It is effortless to get the car sideways which is fun, but is not a good feeling when taking sharp turns. The car is on H&R Race springs and 150k mile Bilstein sports which seem to still ride okay and the rear camber has not been fixed. I'm currently running 205/55/15 tires. The fronts need to be replaced but the rears are still okay. I'm considering buying all new tires and running a 225 on the rear but I'm not sure if that will make much of a difference.

I'd really like to take the car up to the mountains or get back into autocross but I don't think it performs as well as it should... definitely not like it was when I had the m42. Just looking for some advice on what to upgrade or replace before I put more money into this car. Thanks in advance!

[WAM3]

When my rear had that feeling it was due to the ruber RTAB and rear subframe bushings being worn. Once I put poly AKG bushes in, the rear end was tight. I got the larger rear bushing which helps reduce negative camber on h&r sport. With race springs, they definitely will help correct camber.

[kronus]

You’ve put a good 80 additional horsepower into the car. You will need to relearn how to drive it.

[ForcedFirebird]

You’ve put a good 80 additional horsepower into the car. You will need to relearn how to drive it.

...and it was an m42 car, so it's worse than an m20 car. The m42 didn't have the ~70lb of trunk tar/deadening.



OP, remove your spare tire and put a couple of 35lb lifting weights in there - it's what many 318-chassis Spec e30 racers do to get the corner balance back in check.

[Victell]

More front sway bar or less rear sway bar

[Codym42]

When my rear had that feeling it was due to the ruber RTAB and rear subframe bushings being worn. Once I put poly AKG bushes in, the rear end was tight. I got the larger rear bushing which helps reduce negative camber on h&r sport. With race springs, they definitely will help correct camber.

Are you referring to subframe riser bushings to correct the camber?

...and it was an m42 car, so it's worse than an m20 car. The m42 didn't have the ~70lb of trunk tar/deadening.

OP, remove your spare tire and put a couple of 35lb lifting weights in there - it's what many 318-chassis Spec e30 racers do to get the corner balance back in check.

Yep, no trunk tar but I do have at least 50 lbs of audio equipment in the back (lukebox and amp).

You’ve put a good 80 additional horsepower into the car. You will need to relearn how to drive it.

This is probably true to some degree but I'd really like to have a little more traction in the rear.

More front sway bar or less rear sway bar

I should have mentioned that I have ST sway bars front and rear. Maybe I should remove the rear and put the stock bar back on??

[Victell]

I should have mentioned that I have ST sway bars front and rear. Maybe I should remove the rear and put the stock bar back on??

I would try that first before spending money on anything else. And if thats feeling better to you try no rear bar as well, carefully.

[ForcedFirebird]

Easy reversible test is to just unbolt the rear links.

[Jb325is]

What tires? I have been driving my s52 car with the 225/50/15 Kumho all seasons that it came with and it's absolutely diabolical. I don't see how people that aren't interested in driving can use tires like this without crashing on a regular basis.

[Sh3rpak!ng]

What tires? I have been driving my s52 car with the 225/50/15 Kumho all seasons that it came with and it's absolutely diabolical. I don't see how people that aren't interested in driving can use tires like this without crashing on a regular basis.

ROFL AGREED I wont go for even a spirited drive without the track wheels/tires r888s on... the general all seasons break loose if I just think about them wrong. Also disconnecting the rear swaybar has made a big difference. Dialing out rake also helps. You do need wider stickier tires. I also run all poly bushings and the rear camber/toe adjusters, you do need to fix rear camber.

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[e30austin]

Not to sound like a dick, but you added about 100 lbs up front and roughly 80 hp. What did you think was going to happen? Also, do keep in mind, the suspension on your car is meant for an M42 engine (different spring rates).

Go take the car for a long, spirited drive over a weekend and relearn how to drive it. My best advice to give you.

[nrubenstein]

ROFL AGREED I wont go for even a spirited drive without the track wheels/tires r888s on... the general all seasons break loose if I just think about them wrong. Also disconnecting the rear swaybar has made a big difference. Dialing out rake also helps. You do need wider stickier tires. I also run all poly bushings and the rear camber/toe adjusters, you do need to fix rear camber.

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A decent modern tire should grip fine. If the car is “diabolical,” then it probably has some other suspension issue. It’s just an M52. It’s not like we are talking about much power here.

That said, I will 100% agree that swap cars handle worse due to the extra nose weight.

[Codym42]

What tires? I have been driving my s52 car with the 225/50/15 Kumho all seasons that it came with and it's absolutely diabolical. I don't see how people that aren't interested in driving can use tires like this without crashing on a regular basis.

Haha damn... I have Kumho all seasons too.

ROFL AGREED I wont go for even a spirited drive without the track wheels/tires r888s on... the general all seasons break loose if I just think about them wrong. Also disconnecting the rear swaybar has made a big difference. Dialing out rake also helps. You do need wider stickier tires. I also run all poly bushings and the rear camber/toe adjusters, you do need to fix rear camber.

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So you don't run a rear swaybar anymore? Also, I know that fixing the camber will make my tires last longer but will it make the car handle any better?

Not to sound like a dick, but you added about 100 lbs up front and roughly 80 hp. What did you think was going to happen? Also, do keep in mind, the suspension on your car is meant for an M42 engine (different spring rates).

Go take the car for a long, spirited drive over a weekend and relearn how to drive it. My best advice to give you.

Yeah, I mean I didn't expect it to drive the same but I also didn't think it would be quite as wild as it is right now. I know the H&R race springs are used in Spec E30 racing so I thought they'd be a good match for the weight of an aluminum m52 and ZF trans.

[dude8383]

I don't run a rear sway bar at all. The car was useless when I would autox it with the sway connected. Went to an event where it rained and couldn't get the rear to stay put... so I disconnected the rear and never looked back. It was still tail happy with the S52 but it was far more manageable.

With the M42 its far more forgiving but I don't miss mine (and that was YEARS ago).

Like the others have said... you need to relearn the car. It's a totally different beast.

[kronus]

one major thing that changes is weight transfer. with that much more power, weight can move front/rear much more quickly with throttle and brake input, which can cause you to have rear traction problems if the suspension is not settled when (newly substantially increased) power is applied.