I found the solution to the B20A "RARE" transmission.

[cygnus x-1]

One thing that might make this easier, is to use the B20 flywheel and pressure plate, and the B18 clutch disc. Or see if The B18 disc and pressure plate could be bolted up to a B20 flywheel. Or even see if a B18 flywheel will bolt up to a B20 crank. This is what Acme Adapters does to get a VW diesel engine to mate up with a Suzuki gearbox. They modify a Suzuki flywheel to fit the VW crank, then there's a simple adapter plate that matches up the Suzuki bell housing to the VW engine.

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[2oodoor]

D series is close. i think you can get the spline in and one bolt in when i tryed with an old DOHC ZC engines box

any b18 gearboxes i find will be available for purchase here.
i have successfully swapped a prelude gearbox onto the b18 bellhousing. Be sure not to mess the 1st and 2nd gear syncros up, they may look the same but 2nd gear will not work!!

VERY interesting, that was the reply I wanted to see, a successful bell housing swap.

Yes get Rob a bell housing so he will be able to sell me his transmission with short gears for my NA. yea yea

the transmission fitament.

[markmdz89hatch]

Guy, thanks for digging this one up from the dead.

I'm going to pull this in a different direction for just a sec. Given that we've (theoretically) established that all the gearboxes have the same bolt pattern, and it's the bellhousing that acts as the "adapter plate" to mate the gearbox to the motors, I have to ask...

...does the B20A, or B18A (or any other gearbox sharing that same bolt pattern) have a factory LSD, or alternatively, have a readily available aftermarket LSD? I know there's one lone ranger out there that does make an aftermarket LSD for the A20 but I need to explore ALL options.

anyone?

edit: for those that need it drawn out (me included) here's what I put together for us to better understand what options we have.

...can someone please look over this diagram and verify that it reflects the facts we've established in this thread so far?

my goal is to add as many gearboxes as possible to the far right. The more we can add, the better options we'll all have for gearing, and aftermarket options...

[cygnus x-1]

Whoa, whoa, whoa, wait a minute.... So what you're saying is that some of the A and B series gearboxes are potentially interchangeable? Meaning that we could maybe use a B18 gearbox with an A20 engine as well? Man would that be cool.

http://hondaswap.com/swap-articles/b...n-guide-29099/

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[2oodoor]

This thread WAS exclusive to the B20 JDM 3rd gen accord and 2nd gen prelude. We have this issue, lack of availablity of manual trannys. Plenty of B20 made it to the US with automatics behind them, and those of us like me would ultimately rather have a 5 speed.
JUst clarifying that before any confusion develops. I have no problem with research and sharing the information of all 3rd gen accord transmisssion hybrids possible but it has the potential to develop into a hole nubba sticky.
(ps, this section does not smiley so.. ;o))

[RobT5580]

The B16A differential fits the B20A directly i have the quaife unit in my car.

[markmdz89hatch]

The B16A differential fits the B20A directly i have the quaife unit in my car.

Rob, is that just the diff, or did you bolt the whole B16 gearbox w/diff to the B20A bellhousing? Also, are you using a clutch spec'd for a B16 or B20? I wonder if the spline on the main shaft is the same with all of these trannys (B-whatever, as well as A20/A18)

Guy --> You're right about my comment opening up a whole new can of worms, but it's really just a reverse thought of what was started. I'm going to put the hush on my never ending questioning for right now. Once I get some sound evidence that that diagram is not just forward, but backward compatible as my hunch suggests, I'm going to post up a new thread with the findings.

Cygnus --> If you're willing, let's connect on PM to see if we can put our heads together and figure this one out. I have a few complete A20A 5sp trannys, an A18, and have access to a few B series (although I'll have to see exactly which B-series that is).

[TWOLOUDNPROUD]

B2K5 ratios are:
1st 3.166 40.68MPH
2nd 1.857 69.35MPH
3rd 1.259 102.3MPH
4th 0.967 133.19MPH
5th 0.794 !62.2MPH
Reverse 3.000
Final reduction 4.066

And

F2K5 ratios are:
1st 3.166 40.68MPH
2nd 1.772 72.68MPH
3rd 1.185 108.68MPH
4th 0.967 133.19MPH
5th 0.794 162.2MPH
Reverse 3.000
Final reduction 4.066

And

93-01 GSR
S80/Y80 ratios are:
1st 3.23 37.14MPH
2nd 1.9 63.15MPH
3rd 1.36 88.22MPH
4th 1.034 116.03MPH
5th 0.787 152.45MPH
Reverse 3.000
Final reduction 4.4

[RobT5580]

Im running just the differential with a B20A5 clutch. I do recall someone on preludepower running a B16/18 clutch but im not sure if it was mixed.

[carotman]

markmdz89hatch, you will have to modify the diagram a bit.

You can't use the B18A or A20A bell housing on the B20A transmission. The B20A transmission can only be bolted to the B20A (or B18A) using it's own bell housing.

What can be done is use the B18A housing on the A20A transmission.

[AccordB20A]

and dont forget the B18 we are talking about is a twin carb dohc 1.8 that also came in the accords kthx

[markmdz89hatch]

markmdz89hatch, you will have to modify the diagram a bit.

You can't use the B18A or A20A bell housing on the B20A transmission. The B20A transmission can only be bolted to the B20A (or B18A) using it's own bell housing.

What can be done is use the B18A housing on the A20A transmission.

Ok, my brain officially hurts now...

...so, I can use the B18A bellhousing with an A20A gearbox (transmission), which means the reverse should also be true (ie. I can use the B18A gearbox (transmission) on the A20A bellhousing). Correct?

...so, i'm going to need some clarification, I thought the original point of the thread was to say that we could use the B18A bell-housing on the B20? I'm sooo confused. for now, I'm going to pull that diagram so I don't confuse anyone. As soon as I get it finalized, I'll repost. Can we connect over PM to get this all figured out.

[TWOLOUDNPROUD]

Ok, my brain officially hurts now...

...so, I can use the B18A bellhousing with an A20A gearbox (transmission), which means the reverse should also be true (ie. I can use the B18A gearbox (transmission) on the A20A bellhousing). Correct?

...so, i'm going to need some clarification, I thought the original point of the thread was to say that we could use the B18A bell-housing on the B20? I'm sooo confused. for now, I'm going to pull that diagram so I don't confuse anyone. As soon as I get it finalized, I'll repost. Can we connect over PM to get this all figured out.

It not the USDM B18a it the JDM twin carb dohc B18a that also came in the accords . I need the JDM B18a bellhousing to for i can put my other B20a in my other Accord.

[carotman]

Ok, I made a quick diagram that shows what works with what.

[cygnus x-1]

Ok, I made a quick diagram that shows what works with what.

That's pretty good! Now my only question would be about USDM vs JDM. To me those are ALL JDM since they don't have the number on the end. Where do the USDM models fit in?

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[2oodoor]

That's pretty good! Now my only question would be about USDM vs JDM. To me those are ALL JDM since they don't have the number on the end. Where do the USDM models fit in?

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I was going to say DUH, but I digress because EDM models could be identified as well. So I stand by you Cygnus! Thank you Carotman, that is a great start !

[2ndGenGuy]

Isn't the implication of that chart more like A18Ax A20Ax B18Ax etc? I'm under the assumption that all the A series blocks and bellhousings are compatible with each other in regards to what's relevant to our cars. Might be gearing differences at the most across markets... Same goes for the B18A I imagine those are the same across JDM, EDM, etc, as well as B20A's. That list could become massive if you really wanted to list out everything. A20A1 A20A2 A20A3 A20A4, BT, BS, ET, ES, EZ, A18, A16, etc etc. There isn't really even an A20A engine is there? I think it's best to keep it simple unless there are differences.

[carotman]

Yes, I wanted to keep this simple. All the A series for our cars have the same block casting. Same goes with the B series made for our cars.

[cygnus x-1]

Yes, I wanted to keep this simple. All the A series for our cars have the same block casting. Same goes with the B series made for our cars.

So if I understand correctly, a B18A1 transmission from an LS Integra will fit on the B20A block? If that's the case then there should be no problem finding transmissions for the B20A.

It also means that I could use an LS Integra gear box (or any other B18 gear box) in place of my A18 gearbox. That would be seriously cool! More gearing choices and an LSD! Woohoo!

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[A18A]

just the b18a not the b18a1

[MessyHonda]

you could also run integera gears with it.

[thegreatdane]

There isn't really even an A20A engine is there?.

Actually there is, I used to have one :)

[A18A]

i also believe they are in all jdm ca5 accords?!?1/.>?!

[markmdz89hatch]

right, ok, so based on that diagram (thanks Carot) I think I'm just repeating what you said on that first post, but the B18A bellhousing is the missing piece to the puzzle that will open up a serious amount of options for all the B20A guys out there that want to move their auto to a 5 spd.

But that also opens up options for us A guys on which tranny we want to run. I already knew the A18/A20 were interchangeable, but now we also have the option of the B18A, which could be cool too. ...more importantly, that 'may' open up other options for us on the B series front for direct bolt-ons. We'll have to see.

[A18A]

it's just a B18A gearbox, the B18A engine is a completely different engine from a B18A1, and gearboxes are not interchangable between them