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Discussion Starter · #1 · (Edited)
Getrags are expensive. It seems this t1000/ Chevete trany will work with a little work for a LOT less. Is this the same trany on the iron duke camaro's?
Seems it would be easier to get parts for too, blow it out just throw it away and go to the junkyard for another one...about $50 at pick a part.
I assume they weigh more, which is a minus. I also understand the shifter is 6 inches back I will just have to live with cutting a bit.


The question is how good are they? Will they hold up in rallycross and solo without losing the syncro's like the stock tranies?

Will they hold up on the occasional spirited take off's or do you have to baby them like the stock trany's if you have a few extra HP?

oh I see that they can be in in GT so I am assuming (again) that it won't be a problem in the rommier manta...right??
 

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I was just thinking about this the other day. this would seem like a good trans for a manta.

1) the manta is roomier and 6 in's farther back doesnt seem like a problem
2) Stronger than the getrag 240.

But what about a trans from an S-10?
 

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OPEL-LESS!!!
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the shifter being back 6 inches further in a manta probably wouldnt be a bother, just need a straight stick shifter as the GT instead of the one bent back so you can actually reach it. maybe i just have bad luck with the S10 borg-werner T5, but i absolutely hate that transmission, its weak as can be and just J U N K. maybe nice for putting cars, but when a 125 HP 2.8 liter S10 can hurt those transmissions, just imagine was a 185 HP rally-cross car will do to it. franks blown 3 in his 89 blazer and i've blown 1 in my 2wd S10, and all the ones in junkyards i find are pretty trashed already too.
 

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Detritus Maximus
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Since the Chevette/T1000 were Isuzu engined cars, what are the odds of later Isuzu transmissions mating up? Maybe like the trans from the Impulse turbo? Stronger maybe?
 

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I moved this to the (newish) Clutch, Transmission and Drive-train Upgrades Forum. I am pretty sure that Keith Lundholm (aka opelspyder) is a proponent of this swap. Have a look around (search for Chevette) and there are a couple of threads discussing this topic.
 

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t-5

The Chevette bell housing is a close match to the Opel one, supposedly, but none of the other t-5 ones are close. Not a big deal, as you should be able to just use your Opel bell housing. The Isuzus we got here all came with a different tranny, with an integrated bell-housing, like the 4-speed chevettes had, and there you run into some issues.

T-5's came with a ton of input shafts, Chevette, 2.8 equipped cars, 4.3/v-8 equipped cars, Mustangs, Volvos, etc., all had a little bit different input, most with different outputs too but the same gear box and center section. Obviously the chevette one is the closest to the Opel one, but the 2.8 Chevy version is the same splines for the clutch disk and just at 3/4" longer, which helps if you want to use the Opel bell housing.

T-5's also had a ton of tailhousings too, the one most easily adapted to an Opel would probably be the s-10 one, because the shifter is as far forward as they made them. The Mustang and Volvo ones are slightly further back, with the Crapmaro ones being pretty much the furthest rearward location.

T-5's are a lot longer, so driveshaft mods are in order, but a lot of the GM and S-10 ones used the same splines as an Opel automatic, so it wouldn't be any tougher than the Getrag conversion from this perspective.

They were constantly upgrading the t-5 the entire run, so the moral of the story is to get as new a one as you can find for long term durability. Also, they used ATF instead of gear oil, and just like Opel trannys you need to keep an eye on level, low level or gear lube killed most of the dead ones you'll find.

As to bolting it up to your Opel bell-housing, here's the scoop. Mantapart used to make and sell the adapters, and a while back they said they were willing to run another batch if there was some interest for @$400 each. Not a lot of savings over the Getrag, so buying from them was pretty much dropped. That said, if you have a friend with a decent sized lathe or mill with a rotary bed, and you have an s-10 2.8 t-5, here's all you basicly need:
-1 piece of scrap aluminum, rougly 10"-12" by 1" thick.
-hold the scrap to the front of the tranny and mark roughly where the 4 bolt holes would go and the input shaft
-measure the input shaft diameter, and machine a hole throught the material just a bit larger than that hole roughly where it needs to be, no real precision required 'till after the hole is drilled, juse "tape measure" accuracy
-once that hole is machined, your machinist will have to take over the measurements, from here on in they need to be precise
-on one side, the engine side if it matters at this point, you need to machine away 1/4" of the entire face of the adapter you're making, with the exception of a ring around the hole the diameter of the bearing retainer hole in the back of the Opel bell-housing. This will "center-up" the adapter in the bell housing and keep everything in alignment, so it's important.
-on the other side, you'll need to cut a circle into the adapter around the hole the diemeter and depth of the bearing retainer on the front of the t-5. It too has to be a good fit, for it's aligning everything too.
-at this point the adapter can be inserted onto the tranny or into the bell housing, so you can mark where the holes are by using a marker through the holes already in the parts to mark on the adapter. Drill the 4 holes for the Opel tranny, counter sink the tranny end enough to use some allen bolts (or even regular bolts if you want to go with a big enough counter sink hole) to bolt it to the bell housing. The ones for the tranny will need to be drilled and tapped, so you can screw bolts into them. Remember, the center is doing all the alignment duties at this point, you just need the bolts to hole everything together.

If you have a buddy with the machinery, and you can score a srap hunk of aluminum off e-bay or somewhere, the whole works is probably not 3 hours worth of work. I was going to make a few myself at one point, but my little 4-in-one isn't quite big enough for the task, and the machinist I did know was my ex-wife's uncle, who isn't on great terms with me anymore. If someone does think they can get these made, I'd sure be interested in one to try out, so let me know and I'll at least supply the materials.
 

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Cool stephen. thats a great idea. anyone up for it?
 

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Opel Key Master
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Chevette Trans

I disagree about the Chevette transmission. I feel it is a great transmission. Doesn't leak as bad as the Opel 4 speeds tend to, and it has never failed me yet. The 5 speed bolts right up to the 1.9 engine. The difference is the top 2 holes need to be olongated/slotted, and a lower shield will need to be fabricated. The automatic tranny mount bolts right into position and you use the automatic driveshaft. You will have to cut about 1-1/2 inches from the nose of the driveshaft. Use the auto tension spring also. The shifter will be 6 inches farther back-so interior mods will need to be done. I like the feel of the shifter position, especially if you are taller or have changed seats over to miata or other seats. As far as racing, I probably would stick to a 4 speed, this trans really doesn't require the use of 5th gear too much, the 4th gear does great on highway meaning it's ratio seems to be higher than a stock 4 speed. I have often thought a chevette 4 speed might be a good switch, but the "5 Speed" is what is hot. I may do this conversion again on another car soon, and will take photos and such.
Keith
1970 Opel GT
1972 Opel GT (On Rotisserie)
1979 Triumph TR7- hard to work on British car I'm trying to sell for more Opel stuff
 

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crazy opeler
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Interesting idea, does anyone know what a machine shop would charge to do that sort of machining?
 

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I have a T-5 Borg warner with a Manta-part adapter

The T-5 came out of a S-15 forget which year first thing I did was put synthetic ATF in it.

the Adapter plate coat $110 back in the day so $400 is just crazy also it took over 6 months with me calling and calling to get it

if you want to know about manta-part ask some of the long time Opelers

i wrote about this so many times but bottom line the T-5 worked great

many many trips to the drag strip and a whole lot of solo II events convinced me that it was a good setup

there are two different gear sets for them but i cant remember what they are
.72 overdrive on both of them i think

on the chevett trans you also have to slot the two upper mounting holes is i remember right been a long time but i had talked to a guy from DC that had one in his GT

i will post some more if i can remember-- back to making an Air box

Davegt27
 

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Adapter plate

I can make this adapter on my equipment, if somebody has material and the T5 or a really good template of the bellhousing side of the T5. I don,t know that I would want my shifter 6 inches further back in a GT however.
 

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Rich, I don't have the measurements real handy, but the T-5 from an S-10 has the shifter forward of the tailshaft which makes it the most forward mounted of the T-5 trannys. Ford and other GM T-5s have the shifter on the tailshaft. When I installed the T-5/V-6 package in my GT, using the rear tranny mount holes in the frame, I had to move the center tranny mount hole back 2.5 inches from the center of the two cross member mount holes to center the shifter in the console hole. HTH.
 

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Turbos are tough trans....

opelbits said:
Since the Chevette/T1000 were Isuzu engined cars, what are the odds of later Isuzu transmissions mating up? Maybe like the trans from the Impulse turbo? Stronger maybe?
Don't know about the 5-speed Isuzu trans but I am in the process of mating up an Isuzu - Aisin-Warner 4-speed automatic trans up to my Opel motor.
 

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OK few other things

the T-5 is a heavy sucker

the throw out bearing slider thing has to be removed from the Opel bellhousing

the T-5 has its own

about 1/2 inch had to be cut off the end of the T-5 throw out bearing slider

already mentioned-- have to use auto drive shaft splines (same as a power glide i think)

one biggy was the ADJ of the clutch. with the adapter plate the ADJ bolt is now two short (could have left the lock nut off and that probably would have solved the problem) so this made for a slightly low pedal

also i had a special wrench that was used for ADJ of the clutch (big pain)

used the stock cross member moved back to the rear mounting holes

the rear trans mount -- the Chevy dealer let me go in the back and let me dig through until i found one that worked (think its from an Astro van)

i did not use the spring but never thought of the automatic one

Super short drive shaft maybe 6" from where you are supposed to measure them. So short they could not balance the thing

there are PICS in the members area but where taken before i got the drive shaft made

when i herd that the Chevett shifter came out six inches further back then stock that made my decision

at the time Getrags where $1500 so it was kind of a good deal

if you can swing it i would go for a getrag but its always better to have more options


HTH
Davegt27
 

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Getrags are expensive. It seems this t1000/ Chevete trany will work with a little work for a LOT less. Is this the same trany on the iron duke camaro's?
Seems it would be easier to get parts for too, blow it out just throw it away and go to the junkyard for another one...about $50 at pick a part.
I assume they weigh more, which is a minus. I also understand the shifter is 6 inches back I will just have to live with cutting a bit.


The question is how good are they? Will they hold up in rallycross and solo without losing the syncro's like the stock tranies?

Will they hold up on the occasional spirited take off's or do you have to baby them like the stock trany's if you have a few extra HP?

oh I see that they can be in in GT so I am assuming (again) that it won't be a problem in the rommier manta...right??
Calvin, I've been researching this swap for awhile. I know of a fellow Opeler that did the deed. The bellhousing and trans must be from a Chevette, with Opel auto trans rear mount, and the driveshaft also auto trans modified (350 chevy u-joint ) up front. If you can score a T-5 from an S-10, then you swap tailhousings, and the shifter comes out nwithin 1/2 inch of the stock Opel shifter with no butcher work. You need to weld a plate to the top of the chevette bellhousing to use the top 2 bolts, otherwise it bolts right up. You cannot use the S-10 with the chevette bell.- totally different size- just steal the tailshaft end. The guts may swap over-no. am working to make a Mopar type pistol grip shifter handle with maybe a gated cover like the exotics have.t tested yet
 
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