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Running a GM automatic transmission behind your redblock

Q

qwkswede

Old and Slow
300+ Club
Joined
Mar 19, 2003
Location
Denver, CO
I think I caught most of the lunatics who would dare mate a TH400 to Red Block Volvo already. But just in case some people are sleeping and not watching the for sale forum I wanted to cross post this... It has progressed from an idea to ordering the parts in about a 2 weeks. We are going to get this done. Its a great way to get a strong transmission behind your high powered turbo volvo...

Adapters are for sale in group buys here:
http://forums.turbobricks.com/showthread.php?t=230330

Details..
icon1.gif
Volvo Redblock to GM Torque Converter Adapter Sale and Group Buy
<hr style="color: rgb(153, 153, 153); background-color: rgb(153, 153, 153);" size="1"> I have been running a TH400 in my Volvo 740 since late last year. There are two essential parts needed. One is the Block to transmission plate that gsellstr is selling. Here is a link to his sale thread: http://forums.turbobricks.com/showthread.php?t=209426 The other part needed for the conversion is an adapter plate that bolts to a GM torque converter and mates to the Volvo flex plate and crankshaft. This is a precision part that takes up the space between the crankshaft and converter and aligns with the center of the crankshaft.

I had quite a few people asking me about the design so instead of just sending drawings to people for a bunch of scattered one off runs; I decided to help out and get the parts made here in Colorado. That way we can get some economy from a bigger run, and I have some decent connections for this type of stuff.

After some initial estimates with the machine shop, and quick material shopping its looking like I can sell these for $250 each. So for simplicity, I'll just make the price $275 total with shipping to anywhere in the US. If you want one in another country, I'll have to recalculate the shipping costs. If you want to pick up in person you can save the $25

I would like to get a list of names that want to be part of this first run. The more plates I can get ordered, the better the pricing can be. I will look into cutting a little better price if we get to 10 plates. For now, I worked prices with a 5-6 part run in mind.

Some details about the adapter...
1. This works for B21/B23/B230 engines.
2. GM transmissions that work are 700R4, TH350, TH400 for sure. All these have been tested. I'm currently running a TH400 in my car. Additionally, 4L80E and 2004R should work, though I'm not 100% sure about the bolt circle diameter on those converters. A custom converter would solve the problem. The bolts holes for the converter are drilled for 10mm bolts. And thats very close to 3/8" for the older standard size American converters.
3. This will work/should with the LH2.4 style flex plate with a trigger wheel on the perimeter. This is a change I made for this batch. My current plate doesn't fit with the LH 2.4 flywheels. Now, it should all bolt together. However, I do have some concern about the trigger signal with the steel torque converter bolts so close to the trigger wheel. I don't know what they will do the the signal when moving past the sensor. Maybe Stainless Steel bolts would fix the problem with the drawback that they are much weaker than a good alloy steel bolt.
4. And last. I am always nervous about selling my hair brained ideas to other people and having some negative repercussions. I'm not a professional engineer, and never said I was. And I can't guarantee that this thing is 100% safe in any way though I try, and I'm running mine with a kevlar blanket around the trans and bellhousing. This part hasn't been destructively tested for an SFI rating or anything even approximating that. This is old school DIY hotrodding. I'm jut trying to help some others out here. So no gaurantees, warrantees, manatees or anything like that are implied. That said, I'll help with technical questions the best I can...


Here is what the current design looks like. This picture doesn't show the removable alignment dowell in the center, but this is the new design....

converter%20adapter.JPG
 
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Ken,

what's the story with torque converters and driveshafts for this swap? Is a custom t/c required or can I pull something from the pull-a-part, or off the shelf at the local autzone?

Re. the driveshaft, did you graft on the front and use the volvo 2-piece d/s or get a new 1-piece d/s made?

best.

Mike

PS... can't wait for the adapter.
 
gotta get an aftermarket converter, but the point of the plate is so you can get any aftermarket converter with a gm pattern on it, and not a custom converter
 
Regarding the converter...

The need for the aftermarket converter is primarily due to stall speed rather than fitment, correct? The adapter plate allows the use of a standard bolt pattern TC, but you get one spec'd with the stall speed you need.
 
You guys are correct about the converter and stall speed. I have not tested any of the huge 12" and 13" converters on the Volvo motor. Those might have clearance issues with the Volvo starter. My 2 aftermarket converter are a 9.5" and 10" for the body size. There are 2 common bolt patterns for GM converters, 10.75" is the smaller one I used and the large pattern is 11.5" (i think). Alot of aftermarket converters come with both bolt patterns drilled on the feet. Mine did, and i had to trim the feet down a little bit to make them clear the starter. A TC with only the small pattern should be fine. Those are common for TH350 and 700R4. And some have suggested V6 TH700R4s and 2004rs will have a smaller converter. That might be a good junkyard alternative.

The driveshaft was easy. Just measure the distance, and have a GM yoke welded to the end of the Volvo driveshaft. The crossmember requires some minor fabrication to make work. I think I paid $100, with a new Volvo center support bushing installed, and all new U joints. I think I had to shorten the shaft. So that made it cheaper than making a longer one from scratch.

Here are some pictures:

10" Art Carr converter bolted to the adapter and volvo flexplate. Notice the unused bolt holes on the converter feet. I had to trim those down for starter clearance. (read as... grind like hell with an angle grinder). The second converter I had "trimmed" at a machine shop so it looks nicer, probably balances better too?
IMG_0511.JPG


Here you can see my crossmember. If you look close, you can see I welded a 1" tall "box" on top of the volvo trans member. And the GM rubber mount bolts to that. The trans mount had to be raised at the rear to make the driveshaft angle work.
DSC02368.JPG


The shifter installation. I Used a cable shifter. It makes things easy.
DSC02367.JPG
 
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Ken, again, many thanks for doing this.

I"ll let you know how a 2004R fits... I found a builder to build me one.
 
gsellstr said:
Regarding the converter...

The need for the aftermarket converter is primarily due to stall speed rather than fitment, correct? The adapter plate allows the use of a standard bolt pattern TC, but you get one spec'd with the stall speed you need.
Click to expand...

no there's another reason, I don't specifically remember any more since that was all test fitted back in 2003 or 4, I think it had to do with the nose of the starter. the other issue you might run in to with a stock stalled converter is that it stalls around idle speed on the volvo engine (a lot of them are well sub 2000rpm stall speed on the gm apps, and that's behind em air chebby tree fiddies and fo-hunerts). I had a 3500 stall converter in mine and it would MAYBE stall up to around 2700.

new converters can be had relatively cheap too, I wanna say the one I had was in the sub-$200 range, so who knows, it might have ballooned on me eventually if the trans hadn't let go first.

Another side note: a lot of the converters are rated to a certain stall speed for a given engine.. small block might stall to 3k, but a big block might stall it to 3500 (and they'll slap a 3500 stall rating on it and move on, you gotta try and find the details). Which means that it'd probably stall to about 2100 in a volvo :lol:
 
The KL plate is still quite a bit more than the plate I've got. :)

Had an idea on the shifter as well. What about using a ZF-equipped shifter from a 7-series? They're a P-R-N-D-3-2-1 pattern, which should work nicely as a drop-in with maybe just some adjustment on the shift linkage arm on the trans to get the ratio correct.

I forgot about the different nose sizes on the TC's. There's 2 or 3 different sizes as well. Probably something to include on the TC adapter details.
 
gsellstr said:
The KL plate is still quite a bit more than the plate I've got. :)

Had an idea on the shifter as well. What about using a ZF-equipped shifter from a 7-series? They're a P-R-N-D-3-2-1 pattern, which should work nicely as a drop-in with maybe just some adjustment on the shift linkage arm on the trans to get the ratio correct.

I forgot about the different nose sizes on the TC's. There's 2 or 3 different sizes as well. Probably something to include on the TC adapter details.
Click to expand...

I like the Volvo shifter idea if its a street driver. They aren't really a race type shifter made to be shifted manually. But it would make a sweet conversion if you could use the Volvo shifters.

Chevy converters all have the same snout diameter. Are the other GM brands different? The 2004R for example? The chevy ones I have seen all seem to be 1.700.
 
varg said:
Read my post again.

Also, they're still available apparently, so I should be able to buy one now.
Click to expand...

You need a converter adapter too. Let me know if you want to get in on the buy. I might be able to get one more into the pool for Friday's machining.
 
I saw something, perhaps on TCI's site that listed a couple different snout diameters, all for the 700R4 I was looking at at the time. I just checked their site and saw only 1 size mentioned. Don't remember where I might have run across it. Could be fuzzy logic in the brain as well...
 
If anyone is interested in doing this conversion. I still have 2 of these plate available from the group purchase. I was holding them for people for a while, but they don't want them any more. Let me know if you want one. They are boxed up and ready to ship.

Price is
$250 plus shipping...
 
thread bump!!!

have not forgotten about the upright mounted redblock version, should have a file ready for Gary soon.....
 

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Very nice! I like the picture... I'm going to have an intake manifold for vertical mounting soon. Maybe I'll do the vertical mount in the fall after I get a few trips to the track this summer with the current combo.
 
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