Mitsu/DSM active rear toe.

Mitsu/DSM active rear toe.

Postby presterone1 » Mon Oct 01, 2012 1:16 pm

It seems like the only feedback I can get on this is people who drag race. I am looking at buying a kit that eliminates the active rear toe in my Galant VR4. I no longer have 4 wheel steering and I was wondering if this would be a good idea for hillclimbs and track days. I currently have one of the eccentric toe adjusters seized in the bushing so I'm going to have to replace it anyways.
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Re: Mitsu/DSM active rear toe.

Postby sachilles » Mon Oct 01, 2012 2:08 pm

Send a message to user skivittlerjimb, he is a galant VR4 guy who has hillclimbed in the last few years. I remember him mentioning the exact same issue. If he doesn't respond right off let me know and I'll send him a message on facebook.
If you use facebook, he is part of the sccv group and would see the message there.
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Re: Mitsu/DSM active rear toe.

Postby presterone1 » Mon Oct 01, 2012 4:23 pm

thanks. Just saw his name below
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Re: Mitsu/DSM active rear toe.

Postby DaveEstey » Mon Oct 01, 2012 5:41 pm

I can't speak for DSMs, but my RX7 has active rear toe and it felt downright spooky sometimes this fall. I'll be replacing the bushings with chunks of aluminum, which should make it more predictable.
1987 Mazda RX-7 GXL (Hillclimb)
1987 Mazda RX-7 Sport (Lemons)
2008 Mazda MX-5
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Re: Mitsu/DSM active rear toe.

Postby skivittlerjimb » Mon Oct 01, 2012 11:47 pm

Definitely a mod that's worth it. There are other ways to accomplish eliminating the active rear toe in built into the DSM/GVR4 rear suspension than the $175 Jay Racing kit, but it's probably the most advisable way. The other ways include welding big washers in place of wear the rubber toe bushing the trailing arm are now. I've heard of folks welding the rear steer arms place as a way of fixing the rear toe and creating an ersatz rear reinforcement bar, but this seems like a bad idea to me. Having rear toe flex under load creates toe-in that makes the rear of the car more "stable" but definitely contributes to the terminal under steer on asphalt that these cars are cursed with.

All the factory 4WS system did was actively flex the rear toe in proportion to how fast you cranked over the steering wheel (P/S fluid pressure spike). This created a cool effect of super fast lane changes at highway speeds and good slaloming, but really offers no advantages in fast or slow track or hillclimb corners, and can lead to a "spooky" handling effect that others have described that have tracked a working GVR4 4WS system. Frankly I'd get ride of all the 4WS stuff you can, rack, lines, actuator arms, etc. and replace it with non-4WS from a DSM. It's all just dead weight. If it's not working now don't bother fixing it unless you want to keep your GVR4 "stock" for the value of that.

It's been a bummer I haven't been able to get the GVR4 out on the track or the hills in the last two years, mostly due to getting deep into Lemons racing, because it really is a fun platform to work with. It will probably never be as quick as the STIs, Evos, and even the DSMs given that it's got a weight, horsepower, and handling characteristics deficit on all those cars, but it's got a great cool factor. The slightly longer wheel base the GVR4 has than the 1G DSMs also makes it easier to drive in the wet and slippery stuff.

17x8 wheels, 245/40R17s, swapping in DSM knuckles and hubs to get the five-bolt pattern, good coilovers (mine has "Hot Bits" which are quite good despite the goofy name), and a fat rear sway bar (I think mine is maybe 26mm diameter?), and getting some sort of rear LSD (again, swapping in the DSM viscous rear is a good idea) to replace the open stock one are the best mods to make to make the car handle well. Power mods are well known of course, and it's relatively "easy" to get 350-400 reliable hp out of the 4G63T with a non-exotic turbo and reasonable inter-cooler if you pay attention to good tuning (DSM Link is simple and has worked for me) and lots of cooling and appropriately sized injectors and a good fuel supply via an upgraded pump.

Watch out for vacuum leaks, boost leaks, and oil leaks, and ancillary coolant lines that can develop small leaks. Upgrading the oil drain tube from the turbo and putting in a better oil cooler than the factory filter sandwich style one are also great reliability mods. Other known failure points I'll fallen afoul of are the clutch slave cylinder (esp. if you put in a stiffer clutch) and the alternator. The alternator is located right near the turbo and gets roasted under lots of WOT use. Heat shield the crap out of it, and carry around a spare alternator, seriously. Lastly, make sure the ECU's capacitors aren't leaking acid onto the ECU board. Lots of places offer replacing the capacitors and cleaning up and testing the board.

Charlie North also knows GVR4s and older Mitsus inside and out, as does Don Taylor.

Any chance you're bringing your car to Philo?
-Jim B.
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Re: Mitsu/DSM active rear toe.

Postby presterone1 » Tue Oct 02, 2012 1:17 pm

Yes I will try and get my car to philo I don't have a level sender in my fuel cell so long trips become quite the adventure sometimes. I have the rear steer deleted as well as Jackal ECU that is a speed density setup. I have seen a build of your car on the DSG website, its very nice. I'm ordering the jay racing kit this weekend, hopefully an easy install.
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Re: Mitsu/DSM active rear toe.

Postby presterone1 » Tue Oct 02, 2012 1:18 pm

Its nice to see an older mitsubishi used for more than a drag car.
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Re: Mitsu/DSM active rear toe.

Postby sdwarf36 » Tue Oct 02, 2012 6:56 pm

DaveEstey wrote:I can't speak for DSMs, but my RX7 has active rear toe and it felt downright spooky sometimes this fall. I'll be replacing the bushings with chunks of aluminum, which should make it more predictable.


I'd say that was more slicks vs. the road crown.
Translating road racing to hillclimbing:
Proper tire selection== nothing hooks up on moss or wet leaves.
Staying on the racing line==anything paved is considered good.
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