5-speed conversion pic

[PeterK]

Since we were just speaking about 5-speed conversions, I thought I'd share a pic of the two HVDA units I'm working on. The top one is for my 3A (aluminum Supra tranny) is being fitted with the shifter housing, and the bottom one for my 4A (from a 94 Toyota pickup) has the bell housing, shifter housing with TR4A shifter, and rear tranny brackets installed.

Just in case you wondered what these things actually look like...

 

[Mickey Richaud]

Nice work, Peter! They look like the same boxes... Are they?

Mickey

 

[aeronca65t]

Thanks!
That'll be helpful to a friend of mine who is considering a similar swap.
Do you have the overall length of these transmissions? (with or without the bellhousing)
Also, if possible, can you give me an idea of the height and width of the actual gearbox part of the trans? (not the bellhousing)
Ta.

 

[bobh]

A couple of links that are useful for understanding the Toyota Transmissions;
https://www.drivetrain.com/transmanualrebuildkit.html
https://www.4wd.net.nz/suprasurf_part2.htm
https://www.geocities.com/spitfiregt6/Supra/supra.html

 

[trboost]

Peter,
I'm in the process now of doing the conversion. My third gear finally said goodby at the 150,00 mile mark. Probably had nothing to do with the abuse. Just picked up a 83 Celica trany W58 & will call Herman soon. The gearing on the pick-up trany is considerably differant than the cars.
Looking forward to a better top end & better cruising rpm's.

Keep us posted with your progress.

 

[71tr]

An interesting aside to the HVDA conversion. Goodparts offers a Nissan rear-end conversion package. His literature states that it is not necessary to shorten the stock TR6 driveshaft if you are running the toyota transmission. The Nissan R200v rear-end is pretty easy to source locally or on ebay as well.

I'm converting over to the Nissan rear end but running a rebuilt TR6 overdrive transmission. Seems that the toyota transmission conversion would match up well with the nissan rear end.

 

[Guest]

My mechanic is doing these two conversions while the engine is out. I got him to do it because that way he can weld the strengthening plates around the diff carrier and they will be done right - whereas if I do them they won't!

He tells me that you have to lock either part of the original driveshaft or the output flange on the box if you are doing both conversions. I haven't seen the gbox yet so have no way to verify this.

Of course I started out intending only to do the rear diff until I realised the stock box if I added the o/d couldn't handle a lot of power, so have a shortened driveshaft that's totally useless to me. He does a really nice job on them btw - I wish my original looked that good...

It's not a big deal to do I'm told, and I'm indifferent at this point because the cost of rebalancing the driveshaft is minor compared to the rest of the work he's doing. I'd have it done anyway as he's changing the U joints while it's out.

I just thought I'd point it out as an fyi if anyone else is contemplating this.

 

[PeterK]

Re: 5-speed conversion pic GEAR RATIOS

Mich, The truck tranny is for my 4A autocross/street machine so the shorter 1st-2nd is OK, 3rd-4th is relatively the same between the two trannies, but 5th can really vary. I don't know how to ID the actual ratio of each gear but I plan to calculate it once they're in the cars.
Here's from the HVDA manual:

For those who asked, these conversions are engineered by Herman VanDerAkker to be a drop in fit, exact dimensions (or smaller). nfi

 

[Guest]

Re: 5-speed conversion pic GEAR RATIOS

Again nfi - I just got off the phone after a long chat with the guy Herman recommends in his emails. This thread inspired me to actually get on with it and order the box (my car is away for at least another 8 weeks so there wasn't a rush).

They basically build them to order and will put any of the ratios that Herman quotes that you want on request.

Cost is of course more than a box from the breakers, but not terrible given the price of the kit. Still competitive with a rebuilt 4sp and conversion to o/d.

 

[Mickey Richaud]

Re: 5-speed conversion pic GEAR RATIOS

I figured that the innards were different, but was wondering about the cases... Just curious...

Mickey

 

[vettedog72]

Hope you will continue taking pictures with the process of installation. Really looks great.

 

[trboost]

Re: 5-speed conversion pic GEAR RATIOS

Hey Peter,
That makes sense. The truck gearbox should be better for the autocross. I picked up a very nice W58 box for $150.00 in a local yard. My first trip out to Conecticut turned up 2 trany's but they were to sloppy.
I can't believe what a nice guy Herman is. We have spoken several times for information & to talk cars. This guy is a true sports car enthousiasts with a true love for the cars & the people.

 

[71tr]

Re: 5-speed conversion pic GEAR RATIOS

alana,
you have a pm.

 

[Guest]

Re: 5-speed conversion pic GEAR RATIOS

71TR - I thought I replied last night. Did it not go thru?

 

[Guest]

Re: 5-speed conversion pic GEAR RATIOS

So to revive this thread slightly.

I was up at my mechanics shop today. The new box and the hvda kit are there now, so I got to actually see them for the first time. That w58 box is LIGHT. Hard to believe it can handle as much power as it can.

The hvda kit is a work of art. It doesn't look that impressive at first - small box and not so many pieces, but the bellhousing is nicely made, and the thrust bearing is really elegant.

It also seems that I was mistaken (or misunderstood what I was told) about having to send out the driveshaft to get it locked as the part comes in the kit, it just needs rebalancing after you install it.

All in all, I'm looking forward to trying it out. I really want my car back...

 

[Guest]

Re: 5-speed conversion pic GEAR RATIOS

I was back up at the mechanics today to get a sample rear hub to send out.

The remanufactured box I bought is now unwrapped and off the pallet. It's missing the speedo drive and the reverse switch. Now I can buy a reverse switch for $20, but the speedo drive is not so easy to find. The company that remanufactures them aren't interested in fixing these omissions, so I would on balance not be willing to recommend them to anyone contemplating this conversion.

I'd have expected better given the premium (more than double) over a salvage box. If anyone is planning on doing business with them I'd say caveat emptor.

/ubbthreads/images/graemlins/frown.gif

 

[derickson]

Re: 5-speed conversion pic GEAR RATIOS

What's your total cost for the conversion?

 

[Guest]

Re: 5-speed conversion pic GEAR RATIOS

Depends on the price you pay for the box. You can get one from a breaker online with a 90 day warranty for under $500. Remanufactured for 2x that. Local breakers for $100 and up. Add 1500 for Hermans kit (approx with shipping) and the cost of a new pressure plate (you get a clutch) and that's it if you do the work yourself.

Mines in the shop, but the engine and box are out anyway so I'm paying an extra $100 to the mechanic to do the conversion while he does the rest of the work. I've no idea what it would cost to get someone to do it, but it will be a number of hours.