Best strength using mostly stock parts? T1 or 002/091 in '65 Bus

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Bobby74
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Best strength using mostly stock parts? T1 or 002/091 in '65 Bus

Post by Bobby74 » Sun Jun 03, 2018 5:19 am

It has been a really long time since I've had to make a post, but I need to get some input on this one. :)

I have most models of transaxles from T1/T2 early 60's-76, all the way through '79 T2 091....
I even have a '78 Bus Auto trans, and I believe a '68/69 002 acorn nut trans. Sold the ultra rare 411/412 trans a few years ago to someone who needed it. ;)

I have a '65 Bus that I converted to T2 68/69 Baywindow IRS.
Currently using a stock '73 Ghia trans using stock '68 Bus axles, T1 CV on inner and T2 CV on out.

Looking for the "best" transaxle combo for a 2270cc Type 4, around 180HP.

Want to cruise at 70mph. Mostly street use, but occasionally take to the strip but use street tires (215/60/R15).
I don't side-step the clutch, and I preload the trans before any hard launch.

I can keep it T1 based for ease, but if T2 091/002 is going to be a better choice, what changes to axle choice does that make?

If using Bus 3rd/4th or Late 113, the factory already welded the hubs, correct? Or do they still need to be welded for added strength?
What upgrades should I do while I'm in there? I can use any combo of parts you suggest.

Budget is $1500-2000.

Thanks for your help!

Casting Timmy
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Re: Best strength using mostly stock parts? T1 or 002/091 in '65 Bus

Post by Casting Timmy » Sun Jun 03, 2018 9:13 am

I'd use the 9 tooth mainshaft, put the 091 idler, 1st synchro, and 091 1-2 slider as well. Early swing boxes had a 1.32 third gear, probably a 1,2,3 drag race if you are going to keep it streetable.

Bus you get a 8" ring instead of the 6" ring in car transaxles.

The 9 tooth mainshaft has splines for the 3-4 hub. The hub will move towards 4th, the stock clips are NLA so you can machine for 091 clips. Slwoly sneak up on it with pressing the hub towards fourth as you don't want end clearance to disappear with hub movement. It's a pain to go through, but well worth the effort. (Press on hub and install clip, then press hub towards 4th on clip and measure clearance, press hub away to remove clip, press hub off)

Bruce plate works for 9 tooth mainshaft or all bus irs, but requires nose cone clearancing with bus. Simpler although install method is with silicone is the thrust plates. I really prefer the Bruce plate or Folt's makes a super duty plate for use with his bus gear carriers and can machine the nose cone if you send it to him.

9 tooth mainshaft you can do 091 or 002 mainshaft bearing, some flip the 002 over so the plastic cage is caught inside. I personally like the race built into the bearing race and would go with the 091 bearing.

If the case calls for the big nut pinion bearing you can use a 113 big nutpinion bearing if you have a good one or machine first gear out the distance of the swing axle washer for the pinion bearing and then substitute a 1st race machine down and a shorter idler bearing.

I'd use metal caged single roller bearings on all idlers, stock had some double roller space double roller bearings I don't like as much as single spaced bearings. 3rd will require popping out a roller and using a thin Dremel wheel to spilt the cage top and bottom to go over the splines. (Keep the square pocket end and pop the roller back in after installation.)

Chromoly pinion nut, bronze clutch shaft bushing, weld the clutch shaft up so the arms don't break, super diff (bus could be converted to 091 diff or 091 super diff but would need 091 flanges on 091 diff and bus cv's)

Gotta run to church, but others will list more stuff I'm sure

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Bobby74
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Re: Best strength using mostly stock parts? T1 or 002/091 in '65 Bus

Post by Bobby74 » Sun Jun 03, 2018 11:19 pm

Sounds good, and I also like the idea of the 091 style race as opposed to the plastic cage style (002). I bet it would get better lubrication and should be a little stronger.

Is the 8" Bus ring gear a lot stronger for street/strip use? I have seen a few chipped 002 rings but never found a T1 style (6") ring that had obvious failure.

The 091 is massive.....
Are you money ahead starting with a 091 or is a good late model '74+ T1 case best for less than 200HP? What about the zig-zag rib '75+ style T1 cases? I have 2 of the T1 zig-zag cases.

Finally.... What about the ERCO 091 to T1 housing and using T1 style shift rods? How much work is it to setup one of these? Does it make the 091 shift like a beetle trans?
Sorry for all the questions but I couldn't find a direct answer to most of them.

Casting Timmy
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Re: Best strength using mostly stock parts? T1 or 002/091 in '65 Bus

Post by Casting Timmy » Mon Jun 04, 2018 6:54 am

The 091 and 002 mainshaft bearings both have a plastic bearing cage. Just the 091 has the thrust washer built into it and angled back, which I like the idea of as the washer can flex out I think.

The 8" rings are stronger, but as you will notice running the numbers they have different ratios. The bus ring and pinions won't do as well with the highway like the beetle ring and pinions that are higher.

The 091 has advantages and disadvantages, there is less of a used market for gear ratios. A late 3 rib and all 5 ribs use the same main case as the 091, the 091 main case is a little stronger than the 5 rib case and a bit more than the 3 rib case. The 5 rib case is usually placed for strength between the skinny ribbed 6 rib and the tapered rib 6 rib.

The T1 Zig Zag cases are the strongest cases from the factory.

Personally I would think about going with a 5 rib or a T1 as I could keep the 002 3-4 catch keys with the synchros for it. I think the 091 with 002 catch keys doesn't match the 091 synchros are well. I also like the idea of no clips on an aftermarket main shaft if using a hybrid mainshaft from Weddle.

If you have a large pile of transaxles I would sell some and get the money to increase the budget. If you're trying to determine best buys I usually don't buy cores anymore unless they're really cheap as they all have a lot fo miles on them. No rebuilders in my city historically means that people took them out for some minor issue and then later someone else "upgraded" their broken box to this great box that just made a little noise. Repeated a couple times and no one ever thinking to change gear oil makes some interesting tear downs.

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Bobby74
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Re: Best strength using mostly stock parts? T1 or 002/091 in '65 Bus

Post by Bobby74 » Mon Jun 04, 2018 10:48 pm

That gives me a lot of great ideas on what direction to go.. Thank you.

You said the zig-zag T1 cases were the strongest cases. Do you mean strongest T1 or strongest overall? (stronger case than late 6-rib?).
I have a NEW German FAG 113/big nut pinion bearing I've been saving for a good case. :P

Too bad I sold a 5-rib a few years ago. It had a good R&P, but I got a good amount of money for it....not what it was worth though!

Since I have so many T1 cores that are in good shape, I think I may go with the T1 if you think a zig-zag case would be best for this?
I think I have all the gear ratios mentioned, especially if I have a box or 2 with the .82 4th.

I can look it up but any idea how many teeth the 1.32 3rd has? I have quite a few 60's boxes, so I may have one. You think the drop will be too far from 1.32 to a .82? Or should I go with a 1.26? The T4 has a lot of torque compared to a T1.

I assume you mean 3.88G or K or are you talking about using a 4.12 R&P?

Thanks again for all the help!

Bruce2
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Re: Best strength using mostly stock parts? T1 or 002/091 in '65 Bus

Post by Bruce2 » Tue Jun 05, 2018 6:36 pm

Bobby74 wrote:
Sun Jun 03, 2018 11:19 pm
Is the 8" Bus ring gear a lot stronger for street/strip use? I have seen a few chipped 002 rings but never found a T1 style (6") ring that had obvious failure.
It's not the strength of the ring gear that matters, it's the pinion gear that fails. A bus R&P gearset is a lot stronger than Type 1 gearset.
There are other factors too. The Bus is a hypoid gear set, so that also means it's stronger.
Bobby74 wrote:
Mon Jun 04, 2018 10:48 pm
You said the zig-zag T1 cases were the strongest cases. Do you mean strongest T1 or strongest overall? (stronger case than late 6-rib?).
You can't really compare the T1 to a T2 case. It's the internal parts that fail, hurting the case usually. Since a Type 1 R&P is weaker than a Type 2, if you're breaking R&Ps, use the Bus trans.. Many drag racers have switched from Type 1 to Type 2 in order to get the stronger R&P.
The zig-zag is the strongest Type 1 case, IMO. Stronger than the earlier SSC case, and half a pound lighter!
Bobby74 wrote:
Mon Jun 04, 2018 10:48 pm
You think the drop will be too far from 1.32 to a .82? Or should I go with a 1.26? The T4 has a lot of torque compared to a T1.
A 1.32 with a .82 is a mistake, even with an engine that makes lots of torque. Years ago I had a 1.26 with a .82 in my car. At the time I thought it was ok since I had quite small diameter rear tires. When a friend drove my car and shifted for the first time into 4th getting on the freeway, he instantly said he could never tolerate that big hole between 3rd and 4th.

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Bobby74
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Re: Best strength using mostly stock parts? T1 or 002/091 in '65 Bus

Post by Bobby74 » Wed Jun 06, 2018 6:58 am

I figured that would be a huge drop from 3rd to 4th, but wasn't sure.

The Ghia trans I'm using now has almost perfect ratios for my Bus and engine. Sometimes it would be better if the gears were a little closer for 1-2-3 since the current ratios feel pretty wide.

It's really tough to decide what direction to go. I think in the longrun, I will probably go with a T2 091 type trans. It really comes down to how much fab work and changes I want to make to my Bus. If I keep it T1 based, its pretty much bolt in already. If I go T2, I have to change axles, mounts/or run an ERCO housing.

I haven't broken any parts with this setup yet, so I may just keep it T1 based until I start breaking parts and then make the big jump to T2/091.

Hypothetically speaking, would a 4.57 R&P do well on the street/strip with a .82 or a .77 4th?
The higher ratio (4.57) R&P would make the trans "feel" more narrow in 1-2-3 than a 4.12 or 3.88, correct?

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