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OPEL-LESS!!!
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Discussion Starter · #1 ·
ok, searched forums for an hour, and did not find much about alternatives to five speeds other than the getrag. me being the cheap kid that i am, and not wanting to put big dollars into my GT to go faster and affect its driveablity, i'd rather do a 5 speed swap, to get the feel of more power, better gas mileage, and driveability is not made worse.

so is it correct if i got the implications that the only other options are the s-10 5 speed and the chevette/pontiac t-1000 trans? and to use these transmissions, you need a opel automatic driveshaft (most chevy splines are the same as automatic opel)? speedo cable must be used from the new transmission also, and the shifter is 6 inches too far back, and the shifter location cannot be changed.....am i correct on all of this, or is there another way that has not been discussed, or is there a way to move the shifter atleast? i know the s-10 cannot be moved, as its what i believe is called a toploader trans.
 

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Old Opeler
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5,564 Posts
Jap Boxes

I'm a great advocate for automatic gearboxes in "around-town" cars - simply because it is so much less stressful in stop-go traffic.

However, there is nothing quite like a slick stick-shift in a sports car!

One of the gearboxes used extensively here is the cast-iron case Toyota Celica five-speed. It is plenty strong and has a detachable bell housing. Is used in every thing from six-cylinder Holdens (to replace stock 3-speeds) to SB Chevy conversions and even as an upgrade for Jaguars.

I have used one in a Holden and have a spare in a dusty recess of the storage shed but had not thought about it till now.
There is also a lighter alloy case model that would be plenty strong for even a 2.4L Opel motor in a light car......

Seems some measurements may be in order!
 

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If it were me I would search the local bone yards for a getrag 240. The modifications to put it in are simple. And you are looking at modifying a driveshaft with whatever tranny you choose. The reasons I would recomend the getrag are simplicity to install, instruction and help is everywhere and the speedo conversion seems to be the easiest. I put one in mine from OGTS for 600 and it was so easy, but that price could probably be beat at a salvage yard.

Just an idea but if the tranny side of the driveshaft is GM wouldn't it be easier to find a suitable back yoke? No cutting or looking for odd drive shafts.
 

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I agree that the 240 would be a good way to go. Easy to bolt in etc, and that 2.0 would be pretty happy with the .86 overdrive :) If you want ill keep my eyes open for one, I've seen a few of them. If you had more power, you'd need to look into something bigger.

----A bit off topic, the 265 getrag has been tossed around on the forum before, and I was curious if anyone had pictures or confirmation of one being stuffed in a gt. I really dont want to cut up the car...or atleast keep the cutting to an absolute minimum. I'm thinking of using a 265 in my 2.4l conversion as they are easy to get a hold of and are more then tuff enough to hold up to that torque. I know the linage is a bit different, but I can come up with an adpater, I'm mainly concerned about the tranny tunnel. Also the output shaft is different, any comments or advice will be greatly appreciated.
 

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OPEL-LESS!!!
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2,116 Posts
Discussion Starter · #5 ·
does anybody have a list of what cars use the 240 Getrag?
need years and or models, and a way to identify them, got lots of junkyards around here, and one of the bigger ones i get stuff at under half of normal cost
 

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crazy opeler
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558 Posts
greensmurf20 said:
ok, searched forums for an hour, and did not find much about alternatives to five speeds other than the getrag. me being the cheap kid that i am, and not wanting to put big dollars into my GT to go faster and affect its driveablity, i'd rather do a 5 speed swap, to get the feel of more power, better gas mileage, and driveability is not made worse.

You will not be able to "feel more power" with the 5 speed, 1-4 has the exact same ratios as the four speed, it just has an extra gear for highway driving.

If you are cheep you can import the 240 from Germany for a lot less than it would be to get one from OGTS, I have seen them sell on ebay.de for around $130 it might cost an arm and a leg to get it here though. You will still need to do all the modifications, but there are very detailed instructions on the web.

There is another 5 speed option, I forget what car it came from but at one time there was an adapter produced so that it would bolt up to the Opel bell housing. Does anyone remember what trans that was?

A side note, it is my humble opinion that the 5 speed is not really a worth while upgrade. I put one in my first GT and unless I was on the highway I NEVER used the 5th gear. So really unless you are doing a lot of driving on the highway and the car is your daily driver, it is not worth the cost or the effort. I wouldn’t do it again unless I was loaded and just got it to "Have" a 5 speed.
 

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crazy opeler
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558 Posts
greensmurf20 said:
does anybody have a list of what cars use the 240 Getrag?
need years and or models, and a way to identify them, got lots of junkyards around here, and one of the bigger ones i get stuff at under half of normal cost

The one that fits the GT was never imported to the US, to get one you will need to get in contact with somebody in europe.
 

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OPEL-LESS!!!
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Discussion Starter · #8 ·
Chris had a good point about the gear ratios it would just be practical for highway use unless you had a lower rear end gear ratio.

did i remember correctly if the kadette rallye had lower gears that fit in the GT rear end with a spacer? the speedo would need calibration, and therefore i'd get a 5 speed with gears inbetween the stock 4 speed and a 5 speed right?
 

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I put the 5 speed in mine so I didn't have to listen to that 4 speed. Not to mention the fact that with more power from the motor I always had to baby that 4 speed. I still remember dropping a gear and punching the old one. Turns out I didn't drop "a" gear. I split the case and dropped the entire counter shaft and cluster gear out on the road. Very ugly experience, and more reason for a better tranny. Not to say everybody is that hard on things, but I like to upgrade before I grenade.
 

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When I see that the pilot bearing in (some?) 2.3 Fords is interchangable with 1.9 CIH Opels it makes me wonder is one of the 5 speeds from a Ford would work.

2.3's where used for many years in cars and trucks.

Garry
 

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OPEL-LESS!!!
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Discussion Starter · #12 ·
ford would probably be expensive, i hear the 5 speeds for the 2.3 for cyl ford is actually hard to find, just from what i hear, i have not tried to find one, or check out their cost.
 

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If I read the post correctly that transmission wuld be a BW T-5, so yes the transmission and bellhousng would be two seporate pieces. There was an adapter sold to bolt the T-5 (and T-4) to the Opel bellhousing. I believe it was sold by mantapart, but I'm not sure. I can supply measurements for the mounting ears since I have a T-4 sitting in my garage if anyone is interested. The T-5 is a good transmission that was used in quite a few vehicles in the U.S., so there are quite a few different gear choises from the factory. There is also a ton of aftermarket support and replacement parts available. Note however that this is a very heavy transmission.

Darrin
 

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OPEL-LESS!!!
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2,116 Posts
Discussion Starter · #14 ·
rallye73, please post measurements. i think more of us would convert to a 5 speed if we had a cheaper route than a 600 dollar getrag or than to cut holes in the floor and fabricate consoles.
 

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All measurements are referenced to the mounting plane between the transmission and bellhousing unless otherwise noted. The transmission measured is an ’82 Borg-Warner T-4 (4-speed), Removed from a Chevrolet S-10 Blazer with a 2.8 litre V6. The T-5 should be approximately the same size, but heavier.

Input shaft: 7 3/8”
Case Length: 24 ½”
Case Body: 10”
Case width: 9” (figure 11” for reverse switch)
Tailshaft width: 4 ½”
Rear Mount: 14 3/8”
Shift Lever: 12”
Speedometer gear: 17 3/8”
Reverse Switch: 5 ¾”
Input shaft height: 6 1/8” (output shaft is the same)
(from bellypan)
Case Height: 11”
(from bellypan)
Input Spline: 1” x 14T (same as Opel)
Output Spline ?” x 28T (need to check diameter, larger than Opels)
Weight: 62lbs (compare to Opel’s 43lbs)

Bell housing bolt pattern: All measurements taken center to center unless otherwise noted.

Upper Bolts: 8 5/16”
Lower Bolts: 9 1/16”
Vertical Distance: 4 13/16”
Input shaft hole: 4 11/16”
(Top of shaft hole is approximately 1/16” higher than the top of the upper bolt holes)

That should be most of the important measurements. If I have left something out please let me know.

Darrin
 

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OPEL-LESS!!!
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2,116 Posts
Discussion Starter · #16 ·
thanks darrin: i'll post the measurements of the stock 4 speed bellhousing and trans tomarrow to compare numbers "side by side" so to speak.
 

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Another transmission that has been discussed here is the T-9. It's lighter and you might be able to get one fairly cheap from a Merker that is upgrading to a T-5.

Darrin
 

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One thing I forgot to note. Not All T-5s will work, unless you feel like changing clutches, or adapting parts. You will need one with a 1x14T input shaft. Given a make, model, and engine I can tell you if it will work. But there are probably too many possibilities to try to list them all here.

Darrin
 

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Uh, not quite

Fist off, the Ford transmissions are out on GP, and on the fact that they use a wierd mounting face.

The GM T-5, in particular one from a 2.5-4 or 2.8-6 car/ truck have the exact same input splines and such as the Opel trans, so the clutch doesn't need to be re-worked. The T-5 input shaft is almost an inch longer than the Opel one, though, so the adapter will need to be that thickness, which really isn't that big a deal, except that the transmission is already VERY long, leaving you with a tiny driveshaft. You may be able to adapt the shorter tail housing from a 4WD S-10 trans to couple to a drive-shaft, but I'm not sure about that. The t-5, with it's aluminum case, actually weighs less than the Getrag, and since the Ford, GM, and Jeep internals are all interchangable, you have some choices for each of the gears if you mix and match or have one built by a shop.

The down side is that the adapter is $480 from Mantapart, and they do not have any on hand anymore. They said they would be willing to make a few more, last time I talked to them, but there are rumors that they are slow to make stuff too. When my "new" lathe shows-up in a couple of weeks I'll whip one up to post some pictures of so you guys can take a look and decide for yourselves.
 
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