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View Full Version : Getting the "feel of the car" at/near the limit



DeLorean
06-01-2011, 11:00 PM
Most of the time on back roads, I drive fast. Getting the feel of the car at and near the limit has always been very important to me for many reasons, and I have noticed that the Delorean at stock ride height does a few... "funny" things. Has anyone else noticed the following?

On a sharp crest, the front wheels don't have very far to go to come off the ground, on rises / crests where the car gets light, the front wheels seem to lose grip first. It tends to get rather funny if you are too fast into this sort of a situation. It seems as though initially you get understeer, followed by oversteer when you regain solid traction in this sort of a situation

On flat ground, coming into a sharp turn a bit too fast under normal conditions, the car will just plow (understeer). applying more power or letting off does not seem to affect this under most conditions.

On take off, 1st gear, coming into a sharp turn, WOT, the car behaves better than most RWD cars I have driven in the past. I guess the weight combined with the lack of a lot of power makes it quite controllable. It just sort of goes, no drama there. Even when I tried intentionally it is rather hard to kick the rear end out in this manner.

Hitting an expansion joint for example, in a sharp turn at good speed under power the car tends to get funny and start to oversteer. This is kind of scary because it is not the general tendency of the car.

letting off the throttle, coming into a sharp turn and getting hard on the brakes is also a bad idea. I tried this in a parking lot to see what would happen, and this makes the car come right around, 180 degrees.


My D at the moment is pretty standard, with new Michelin pilot exalto A/S's (about the only fair-good tire you can get now in the correct size). Are these characteristics pretty normal? I normally drive an 2011 STI, and I do not expect the DeLorean to perform like that, and respect it for what it is, but I find that it's quite a bit more of a "challenge" to keep the DeLorean at a high rate of speed while speeding through the Pennsylvania back-roads.

DMCMW Dave
06-02-2011, 12:38 AM
Lowering the front end will make an absolutely huge difference. You are correct, the shock are near the limit of upward travel when sitting, so the front does get "light" easily. The othe issue due to the nose-high attitude is that any compression causes the front to go to a toe-out condition.

When you lower the front, you get the shocks more centered in travel, AND you get to set the static toe such that spring compression or expansion cause toe-in, which feels a whole lot more stable. This is because a lowered car will have the tie rod ends almost exactly horizontal at rest, where with the stock springs there is a very notable angle downward from the rack.

thegovernor9912
06-02-2011, 07:13 PM
my experience has been understeer, followed by understeer, with an additional extra schlopppy addition of understeer. The only time I have gotten the rear sideways, was when I was doing it on purpose using the combination of throttle and diminished traction(either dirt or rain).

I haven't done it but I assume if you try the "scandanavian flick" on the DeLorean you can get it to spin.

My car has brand new Mastercraft tires, lowered with marty miar's KYB shocks, eibach springs, boxed control arms, Toby's front sway bar kit, the european LCA bushings, and the front strut bar. I end up driving the car rather fast, especially when trying to keep up with the local Lotus club...

Upgrading the 30 year old suspension will def help out how the car feels before you get to the limit of traction, and I highly recommend you do that.

DeloreanJoshQ
06-02-2011, 09:46 PM
What is, "Toby's front sway bar kit"? Do you mean bushings?

mluder
06-03-2011, 02:58 AM
Has anyone encountered a problem with sterring whell vibration at freeway speeds? It seems like when I get into the neighborhood of 50-60 mph I get a little shimmy from the steering wheel. It's not like violent but noticeable.

I once recall reading something about balancing the tires for a different size then what's actually on there.

Anyone?

Steve
#4456

thegovernor9912
06-03-2011, 08:10 AM
What is, "Toby's front sway bar kit"? Do you mean bushings?

Yes, I also heard he is coming out with a add-on rear sway bar.

DMC3165
06-03-2011, 08:33 AM
Has anyone encountered a problem with sterring whell vibration at freeway speeds? It seems like when I get into the neighborhood of 50-60 mph I get a little shimmy from the steering wheel. It's not like violent but noticeable.

I once recall reading something about balancing the tires for a different size then what's actually on there.

Anyone?

Steve
#4456

I have this same exact problem. Both DeLoreans I owned did the same thing regardless of what suspension setup I had in either car and one even had aftermarket rims. Two of my stock rims now on 3165 are slightly out of round and I have a connection at a powdercoating shop that does wheel repair and they said they can fix it for me. But it may not make a difference so I'll probably just live with it. I have tried different balances but its made very little difference.

louielouie2000
06-03-2011, 09:41 PM
It seems like when I get into the neighborhood of 50-60 mph I get a little shimmy from the steering wheel. It's not like violent but noticeable.

Every single DeLorean I've ever driven has done this. I think it's inherent to the beasts. It may even be harmonic resonance from the tires & fiberglass underbody.

DeLorean
06-04-2011, 10:02 AM
Well at highway speeds, mine is pretty solid feeling but there is ever so slight but noticable steering play. Between the steering rack itself, the U-joints, the inner rod ends, and the rod ends all being original on my car- when I checked it out, just about everything has a miniscule amount of play, but it apparently adds up.

If you DO have any sort of shimmy it's probably related to tire balance or some other rotating assembly like a drive axle. Steering play, even VERY slight will exasperate this feeling. It will also make this feel worse if you have shot brake rotors.

Jacko
06-04-2011, 10:22 AM
I think the slight shimmy at highway speeds has to do with the Lotus design front suspension using the anti-roll bar to locate the fore and aft movement of the wheel. This design allows slight movement of the wheel hence the shimmy.
Although I read years ago a quote from an 'authority' on D's that any shimmy in the front end is the result of an unbalanced tire ... period. Additionally, if the service is available in your area the tires should be balanced on the car. The complete rotating mass is balanced.

DeloreanJoshQ
06-04-2011, 10:52 PM
My car has the slight shimmy as well. I had the tires re-balanced and the shimmy was still there, ever so slight. I believe if the lower control arm bracket upgrade is added, it might help...maybe someone can chime in on this...I will be doing the upgrade in a month....

thegovernor9912
06-06-2011, 08:10 PM
I had my control arms "boxed" in and it didn't help with any of the front suspension play I had. It did greatly improve hard braking, almost eliminating the nervousness the car exhibits in these instances.

Lotus's design of doubling the sway bar as a strut rod, was not one of their best. It does fit Chapman's desire to simplify things though...

DeLorean
06-26-2011, 12:40 PM
I have also noticed that under hard braking on bumpy or un-even ground the steering wheel really likes to jump around a fairly significant amount. I am wondering if this kit to reinforce the LCA's will help with this? -

http://www.delorean.com/dmcmidwest/images/lowercontrolarmkit600.jpg

I really notice this the worst when coming into a corner I can make around at about 40 mph coming in at about 80, while hard on the brakes - a few pot holes or pavement imperfections during this maneuver really "shake things up" On a track or fairly flat ground this would likely not really ever come up... I'm not sure how well controlled the front wheels are for this sort of driving with the factory sat up which uses the front ARB to double as a guide / track rod. Granted, plenty of other cars are set up like this too (saturn SL/SC for example), but typically the ARB is HUGE on this sort of set up.

I also suspect that an upgraded front sway bar may also help with this "bad feeling" when hard on the brakes over bumps.