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Sanctifier
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Joined: 07 Apr 2005
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Location: Good question!
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 Posted: Tue Jan 12, 2010 12:59 am Post subject: ~ How-to Guide: PERFECT Evo Handling with LITTLE Understeer. |
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| 2nrM wrote: | Hey man. I got some replies from you wrt an Evo7 ACD transfercase being paired with a non ACD rear diff.
You sound very knowlegeable on this subject. Can you give me your number so I can give you a call please. I can even pay you for your time. Thanks.
2nrM |
Hi 2nrM,
I can even pay you for your time... Thanks for the compliment but I'm not a professional mechanic, my friend. For what it's worth, my suggestions are free... I hope they help.
Evo7 ACD transfercase being paired with a non ACD rear diff... As I said; I'm no expert on the subject.
I'm just researching the same swap for my daily-driver Evo 6 TME 'Clone' now.
| Sanctifier wrote: | Remember...ALL USA E8s and E9s have ACD... with no rear AYCs.
They all have cast-iron LSDs that are MUCH stronger (and gives more consistent handling IMHO.) |
The whole purpose of my E9 ACD swap is to use an ACD T-case instead of the E6 Viscous coupling centre diff. That way I can "reflash" the auxilliary ACD/AYC ECU... get more rear torque transfer... to increase "rotation" (controlled "throttle" oversteer) and also reduce understeer for improved handling like a rwd car.
Unlike common local opinion, I still find that 4wd Evos (and WRX STi's especially) behave like "FWD cars on steroids." IMHO they ALL will eventually put you into DEEP SH!T one day if you're not careful... and NONE have consistent handling characteristics, so it's difficult to get quick (and consistent) AutoX times. This way, I think that I'll get my Evo 6 'Clone' to behave more like a good handling RWD car.
I can't remember if I sent this link before but I got some advice from a 2nr on MLR recently...
Link--> Evo 7 transferbox on e6 gear box.
Based on what Simon says, I think it may be easier (and more reliable) to leave the Evo 7 transfer-case intact and NOT swap bits into E6 T-case housing... Especially since Evo T-cases (and parts) are so scarce (and EXPENSIVE) locally!
I'm thinking about using an E7-E9 engine-to-crossmember mount arrangement, instead of the OEM Evo 6 engine mounts...
That way, clearance for a 3" E7-E9 downpipe will also be possible in an E5-E6 shell... ???
Don't forget that you'll still have to cut and "massage" the centre-tunnel and floor-pan for ACD, exhaust down-pipe and modified drive-shaft clearance.
I'll have to import (eBay) an E7-E9 driveshaft... and modify to fit, if necessary... Don't know for sure yet... but IMHO that's MUCH easier than trying to swap T-case bits between E6 and E7 models. Then... I'll use my E7 full harness... and the ACD pump & reservoir that I bought last year (eBay)...
This info might help too... Link--> Remote ACD reservoir relocation kit.
My $0.02¢
Feel free to call. Much quicker than "PMs"... 684-4552 (C) /633-4552 (H) / 622-5196 (O).
Wade.
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Sanctifier
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Joined: 07 Apr 2005
Posts: 1794
Location: Good question!
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| Posted: Sat Jul 28, 2012 5:24 am Post subject: |
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^ ^ ^ UPDATE! - And LONG overdue! 
Yup a reflashed Evo 7-9 ACD is a VERY good solution to the Evo 4-6's understeer problem.
One thing though... | Sanctifier wrote: | If you use an E7-9 Transfer Case with ACD it MUST be used with a rear LSD from the same model.
From what I've been told, the E4-6 Transfer Case rotates in the opposite direction to the Transfer Case from E7-9. |
But there's another solution too... and it's VERY effective!
| Sanctifier wrote: | The "sting" IS in the tail!  |
More info coming soon! 
Stay "Tuned!"
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Sanctifier
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Joined: 07 Apr 2005
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Location: Good question!
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| Posted: Fri Aug 03, 2012 4:12 pm Post subject: |
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| Sanctifier wrote: | | The "sting" IS in the tail! |
Yup... and here's the solution!...
| Sport Compact Car wrote: | Bozz Performance EVO VI
DRIVETRAIN
Drivetrain modifications:...  high-close gearbox with stock center diff, Cusco twin-disc clutch, Cusco adjustable LSDs front and rear (adjusted very tight in rear, loose in front) |
Okay, so Cusco front & rear LSDs cost the earth!... but there's an economical alternative that's just as effective!
So where do I get such a rear LSD?... Here's where---> Link--> Team Rip Engineeering - USA.
This is what you should buy... Link--> MAX-LOCK 12 Plate Upgrade/Rebuild Service... $535.
It's EXPENSIVE... and your Evo will be "down" for a while because you have to "pull" your LSD and ship it to TRE (FedEX etc.)...
but this is what you get for your US $535 (+ options) + 2-way shipping + duty + VAT... 
| TRE wrote: |  magnaflux inspection of differential carrier housing and bearing caps
magnaflux inspection of ring & pinion and spider gearset
12 new friction & drive plates
shot peening of ring & pinion
shot peening of spider gearset
new pinion & carrier bearings
new shim kit for preload of both pinion shaft and carrier housing
adjustment of the spider gearset backlash
modified sheaves & cross shaft
Gyra-finished sheaves & cross shaft
adjustment of ring & pinion for high torque applications
new pinion shaft and axles shaft oil seals
a heavy coat of satin black paint so it looks like new again
new fill plug
new drain plug
new carrier cap bolts
new rear cover bolts
new rear cover with oil sight glass is optional. $100.
new HD side cover is optional. $285.
new TRE spool is optional.
new HD pinion spacer is optional. $85. |
And this is what an Evo is like to drive after a "tight azz" upgrade...
| Sport Compact Car wrote: | The Wizard of Bozz: Beauty and the Beast.
I've only driven two laps and already this car is like an extension of my body. No, my body could never be this good, it's more like an extension of my imagination. No, not even that. I probably couldn't have dreamed this one up if I tried.
I'm on a small side track at Japan's famed Tsukuba circuit. The track is short and tight, just over a mile per lap, and it's crowded with Mitsubishi Lancers. It's an open track day for customers of Bozz Performance, and every version from the original Lancer Evolution to the brand-new EVO VII is here. This should be a fast batch of cars, but from the driver's seat of this beast, it might as well be a meeting of the Chevette club.
Sliding out of Turn Eight onto the front straight, I spot a purple EVO VII already halfway down the straight and still accelerating. He's mine. I mash my foot to the floor. The car erupts, and emits a terrifying, evil sound from the exhaust, like Satan himself just ripped one in the back seat.
Third gear. I just passed an EVO III. The acceleration is ridiculous, there's hardly enough time to get your hand back on the steering wheel before you have to shift again. Fourth gear. I'm at the EVO VII's rear bumper and going way too fast not to pass him now. I dive inside and brake hard for Turn One, a 90-degree right. I notice a well-worn black path from exactly where I'm braking, straight off through the grass and into a bare dirt patch on the berm. This would be a bad time for understeer.
Thankfully, the car has wicked turn-in. The nose points around the corner. The tail doesn't follow. I slide, arse first, across the EVO VII's nose. He probably doesn't appreciate it. Mashing the throttle, there's nothing. I was so pre-occupied with slowing that I forgot to downshift. Still sliding, I fumble around with my left hand until I find second gear. There, boost! All four tires start spinning. All four 255/40ZR17 Bridgestone RE540 road racing tires. That's a lot of rubber. Actually, now that's a lot of smoke.
Even with spinning tires, there's bungee jump acceleration. The car straightens, turning my fumble into a heroic pass. There's another 90-degree right, so close, the two turns blend into one. I grab third, mid corner, and the car starts to understeer. I jump off the throttle and back on, making the tail step out. The tires start spinning again. In third gear.
Let me reiterate, just in case you didn't get that. The tires are spinning. The car is in third gear. All-wheel drive. That's four tires spinning. Just wanted to be perfectly clear on that point.
The tire-spinning slide continues all the way down the short back straight. At the braking point for turn four, a tight 180-degree right, the car is still arcing to the right; the steering wheel still turned left. I slide onto the rear bumper of an EVO VI. He drives off the track to get out of the way. Still sliding, top of third gear, I ease onto the brakes and the slide tightens. This is amazing. I haven't had traction for half a lap, I'm sitting on the wrong side of somebody else's car and I just managed to string three corners into one, beautiful slide. What a car.
Giddy with red-misted confidence, I grab second gear to power out of the slide and... no boost. I hesitated half a second too long, and slowed too much. Doesn't matter, there's traffic anyway. I crawl around the next corner, holding up the tail of a four-car EVO conga line.
Apexing late, it's hammer down the capacitor kicks in, and all three Lancers are gone at once. Looking in the mirror, I half expect to see two flaming tire tracks, and maybe Christopher Lloyd's dog, Einstein. Instead it's just a swarm of EVOs flittering around in my wake like so many autumn leaves.
Oh, left turn! Gotta look where I'm going.
Back on the brakes, the tail is wandering away again. I'm sliding left, the track's about to go right. There's a wall on the outside of the turn. My heart jumps and grabs hold of my trachea as I remember my freshman physics class. Then I remember rally school. A little picture of Tim O'Neil floats above the car, playing the air steering wheel and talking in his soothing New England accent. "Release the brake, stab the gas, release the gas, countersteer, downshift, back on the gas."
The car snaps around, the tires ignite again, the shutter clicks, we get the cover shot, and here's another 90 right. Brakes. Gas. Both at the same time. Whatever. Another whirling trail of tire smoke follows the car onto the front straight. The left rear tire just touches dirt exiting the corner. The guy in the flag stand is cheering. I need a cold shower...
Getting the car to handle this well took more than less weight and big tires. Adjustable everything was actually painstakingly adjusted. Hisada gathered a group of drivers, a shop full of technicians and took them to the track for a day of sorting. The drivers, Satoshi "Gorilla" Saito, Kasuhiro "Professor" Koisumi, Horoshi Hashizawa, and Yuichi Moriyoshi were chosen for the varied driving styles, from gymkhana specialists (Japanese gymkhanas are similar to our autocrosses, but with tighter courses that reward all-wheel-drive power slides) to magazine test drivers. The hope was their varied input would result in a well-rounded car.
Time after time, the drivers would take a few laps, make suggestions, and then stand back while the adjustments were made. Some, like damping changes, were simple. Others, like the pre-load of the Cusco front and rear differentials, required extensive teardowns.
No detail was overlooked. At the suggestion of Rays Engineering, the wheel sizes were even staggered, with a wider, 9.5-inch wheel in the front, and a narrower 8.5-inch wheel in the back, both wearing the same 255-width rubber. The theory here was the front tire's carcass would be more square, offering high grip and exceptional turn-in. The rear tire, rounded from squeezing onto the narrower wheel, would break away more progressively.
It worked. Combined with a very tight rear limited slip, a very loose front one, a massive 26mm rear anti-roll bar, the strangely distorted tires offer the grip you expect from a track car, with the progressive breakaway and easy slide control of a gravel car. To a rally-driving power junkie like me, this car is perfect... quite simply the most entertaining car I've ever driven. |
This is where I'm going with the Evo 6 'Clone.'...
| Sanctifier wrote: |  E8 Transfer Case w/ACD & Pump  (+ ACD ECU Reflash)
rear Evo 8 LSD (+ Max-Lock Upgrade.)  |
... These two upgrades should solve the understeer once and for all! 
My $0.02¢
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VK-Sportsman
Zorce Jedi Apprentice
Joined: 05 Nov 2005
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Sanctifier
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Posts: 1794
Location: Good question!
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| Posted: Sat Aug 11, 2012 7:28 am Post subject: |
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Hi VK. Yup, IMHO you have to do three things at the same time...
Playing with alignment setings with aftermarket bits will alter handling characteristics...
But the actual speed through the corner will not be significantly increased... with the emphasis on "significantly." Increased adhesion (wider tyres) is the main answer to that issue.
Altering torque transfer with the two "mods" above... AND using aftermarket bits (alignment)... AND increased tyre widths (adhesion)... will increase overall speed through the corner and improve handling characteristics and driver feedback.
You'll have to excuse the confused thinking... Just killing time 'till the water receeds...
Right now we're flooded out in Petit Valley (2.5 feet water... now 2-6" mud) and waiting to start the clean-up... FU(K 
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