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H6 5spd d/r tranny swap


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I know I asked this before... but after several hours of burning my retinas on archives... Which 5spd d/r bolts to the H6 motor? I've got my H6 and my turbo for my Brat and I need the tranny to get this insanity rolling. (It's a Gen 2) I also remember someone saying that the donor flwheel would be the same as the H6. True? Thanks, Ski:headbang:

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the standard ea82 trannies are a little weaker, but will bolt up. Since you're going turbo you want a tranny off a turbo (rx) or from an xt6, but I don't think the xt's got dual range.. Try to get an RX tranny and rear diff.. I think this would probably be best for what it sounds like you're trying to do.

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I'm fairly ignorant on the newer Subes. What year RX would have the d/r and is it a direct bolt on? Flywheel? If I go with the EA82 tranny I don't need the rear diff but if I go RX I have to have it do to the ratio change, Yes?

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So this is sounding like you're swapping the XT6's 2.7L H6 into another car? Your best bet would be either an XT6 transmission or the RX transmission. Both are full time 4WD. If you grab the RX transmission, it has a dual range and a rear LSD. The RX has a gear ratio of 3.7. The XT6 doesn't have dual range or a rear LSD, but it has a gear ratio of 3.9. (we're speaking strictly 5 speeds)

 

As for flywheel, use the XT6 flywheel. Its lighter.

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RX's came from '85-'89. You want to find one from '87.5-'89 since they will have a Full Time 4wd dual range 5-speed with locking center diff, and a rear LSD as well. You can use a XT6 flywheel and clucth with any EA82 tranny as well.

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if lifting for bigger tires for off-roading (not rallying) (27"+ tires) then go for a 5 speed D/R from a carb or SPFI 85-89 wagon.

 

the RX D/R or FullTime Box will be better if you are Rallying (no lift)....

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Did the RX have a part time version? Daily driver and wheeler it will be me thinks...

 

Just a clarification: The Full-time 4WD of the RX has a center differential. It acts like a normal AWD car on the road. When you lock the center differential, it acts like the d/r 5 speeds of the part-time EA82s, plus the LSD gives you more traction. It's the best of both worlds, and it doesn't hurt it to drive it on the street (with the diff unlocked).

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I guess on top of durability for the bigger engine, lift and bigger tires, I'm also wondering about the mpg difference from FWD to AWD. It sounds like the AWD with the diff is more or less a 60/40 power split until locked like the old full time Chevys. If the mpg is negligable, then it sounds like the lower ratio and LSD on the AWD is the way to go...If one can be located.

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I guess on top of durability for the bigger engine, lift and bigger tires, I'm also wondering about the mpg difference from FWD to AWD. It sounds like the AWD with the diff is more or less a 60/40 power split until locked like the old full time Chevys. If the mpg is negligable, then it sounds like the lower ratio and LSD on the AWD is the way to go...If one can be located.

 

what do you think your ratio of road driving to off-roading will be?

 

what size tires will you be running?

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Apparently I'm snorting too much starting fluid at work... The tires I'll be going with will be 225/235 75R15. After looking back on that I had to go to the tire size calculator and run numbers. I'm sure this changes the opinion. BAD Ski, BAD Ski!!! Is the wagon tranny going to take 200HP?

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Apparently I'm snorting too much starting fluid at work... The tires I'll be going with will be 225/235 75R15. After looking back on that I had to go to the tire size calculator and run numbers. I'm sure this changes the opinion. BAD Ski, BAD Ski!!! Is the wagon tranny going to take 200HP?

 

the're still gonna be bigger than 27's so I'd still go with the wagon tranny...

 

how big a lift?

 

I probably have the same street/offroad ratio, but it's still my offroader, and I would definitley take the better low range for off-roading.

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So let me get this straight... you are putting an ER27 into a Brat? With a turbo? And then lifting it? For a daily driver?!?!

 

Since no one has asked this stuff:

 

1. Are you aware you will need to relocate the radiator?

 

2. The ER27 is much too high compressio to run any sort of turbo.... are you putting in EA82T pistons? Even so, the heads are the same design as the EA82 MPFI head, and are most likely not going to handle the added heat of the turbo. If you change the pistons, you might be able to reliably run 5 lbs on it or something. Basically the ER27 is the EA82 with extra cylinders - ask around the board about people that have run even a carb block (9.0:1) with turbo heads - lots of power for about 5,000 miles. The ER27 is going to be 9.5:1 same as the EA82 SPFI and MPFI. Then of course there is the totally seperate issue of the cams.... you'll have to have custom cams done.

 

3. Fuel management - I hope you have some ideas - megasquirt I guess. Stock ECU isn't going to cut it. Might as well do crank fired ignition and do away with the disty while you are at it - one less thing to get wet.

 

4. Turbo engines are generally not good for off-road. For one it's difficult to keep them spooled, and at lower non-spooled RPM the turbo is just a big anchor backing up your exhaust flow. Also off-roading in a lifted Brat with 235's (you'll need more than 4" for 235's BTW) is going to be mostly slow crawling and some speedier stuff, but nothing over 20 MPH really. That's going to be rough on the heat situation - turbo's generate a lot, and to get that turbo power you'll need to get it spooled.... even more heat.

 

5. Daily driver..... :lol:. Your mileage with 235's will be worse than most large SUV's. Think 15 MPG with a turbo ER27 and those tires. I get 20 - 22 in my wagon with 215's and an EA81. Turbo's SUCK the fuel. Ask anyone with an EA82T. Mods just make them suck more fuel too. For comparison I get near 30 in my stock Brat.

 

Just some stuff to think about - don't want to discourage you, and the ER27 is a great swap.... I just think the turbo part is a waste of time for what you want.

 

GD

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Yes, I know I have to relocate the rad. I've looked and taken some measurements and with some fab I can drop it down and forward keeping my bed free. You did bring up some valid points. I was going to have cust cams ground. As far as the turbo issue on the bottom end... I've got a few friends who have the 22R turbo trucks and they really have no complaints. Granted they're not remotely the same bird and there are more gearing options for Toys. There are ways to relieve back pressure on the bottom end. I didn't know the CR was that high on the ER27, but I do know there have been 3 or 4 successful builds of this type and I'm still trying to track the owners for info. Yes, the fuel injection is going to be a pain in the a**. Again, more info required. With your points I am re-thinking. What would your recommendations be to sqeeze more ponies out of the ER27? I'll start a separate thread for that......

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