5-speed conversion or not

[Keith_M]

My bugeye is now in the body shop, and I'll continue posting pictures and updates to my restoration thread in this forum. However, as I start considering options, I'm torn about whether to do a 5-speed conversion or not. I have a rebuildable 1275 engine and a rebuilt ribcase transmission (rebuilt professionally about 20 years ago and sitting dry ever since). But the allure of a 5th gear is strong.

It seems that most people use a Datsun 210 transmission for this conversion, but I also see a very expensive conversion kit in the Moss catalog that uses a Ford transmission. I'm building the car for my wife, who will probably rarely drive it over 60 mph, and who likes the feel of the ribcase transmission in my 65 Sprite (short gearshift throw, crisp shifting).

How difficult is the conversion, and what problems am I likely to encounter? How does the tranny feel compared to the original? And has anyone had experience with the Moss kit? I see the Datsun transmissions come up for sale occasionally, so if I'm going to go that route, I need to start looking for one.

Any opinions and/or experience that you're willing to share would be appreciated.

 

[bug_sixty]

Many a comment on this chat line... Besides the lower rpm's on the 65 mph (up) highway driving that make it sound like a top ready implode, the larger than life for the wife who's running around town or country roads will be the sycro in 1st.... every time your in the passenger seat and she forgets to make that complete stop be for the shift....the wince or look orrrr whatever will be the end of a fun experience..... DO IT for the marriage Keith haha

 

[Rut]

Keith,
Synchro 1st x 2! I'm always the driver and when my wife does drive it makes me nervous. She's a great driver in her own right, but I prefer to be behind the wheel.
Rut

 

[Jim_Gruber]

Rut,

Take a look at Gerard's Kit and video. A beautiful piece of hardware that will never be seen but done absolutely right.

 

[drooartz]

To give the opposite view, I ran a ribcase and 3.90 in the Tunebug along with the 1275 and it was a pretty good pairing. Certainly cheaper, and I liked the shift feel. If I didn't live in the mountains I'd probably go that route again...

...that said, I do live in the mountains and will go with the Datsun 5-speed and 4.22 rear end in the new Bugeye. Never felt the 3.90 was a good match for my local roads, needed more revs for the passes especially at freeway speeds. I like the Datsun conversion over the Ford T-9 version as the Datsun one requires no cutting to the car. Need to start looking for a transmission myself.

 

[Rut]

Jim,
X2 on Gerard's kit and that's the direction I'm leaning. I'm preparing 2 transmissions, a 210 and an SCCR...both are in very good condition. I do need to flush both and will start a separate thread on that.
Rut

 

[aeronca65t]

The five speed is nice, but to be honest, the normal ribcase trans is a wonderful unit.
The shift linkage on a ribcase is excellent....as a sports car should be. I can't think of anything that shifts better.

The lack of syncro first gear is very minor in my view, but I rarely sit in stop-and-go traffic (plus, I can double-clutch with the best of them :friendly_wink: )

A 1275 with ribcase trans and a 3.7 final drive is an excellent and simple combo. That would be my choice.

 

[RickB]

Get a 3.7 for $175 here (NFI):

https://seattle.craigslist.org/tac/pts/4174337015.html

(maybe you could persuade him to remove the pumpkin and ship just that to you.
If you're ambitious then just the gears...

 

[Keith_M]

Thanks for all these comments. They've been really helpful. I wasn't aware that the Ford conversion required any frame modifications, and I certainly don't want to do that. Overall, I'm leaning towards the ribcase because my wife drives my '65 Sprite all the time and has no issues with the lack of synchros in 1st (I've taught her well!), and I doubt that she'll ever exceed 65 mph, and even that will be rare.

As was pointed out, the shifting of the ribcase is good, and I don't want to lose that aspect of the car. I hadn't considered at 3.7 rear end. I have a 3.9 now. My own simplistic analysis of this is that a 3.7 will yield about a 5% reduction in rpm's for a given speed. Is that correct? For only $175, it might just be worth it.

 

[MCS]

Best modification I ever made on my Mk III Sprite. The 210 transmission shifts so smoothly, very nice to engage first gear before you stop. The 5 th gear is welcome when driving with a pack of Big Healeys, I did a 125 miles today on the freeway at 60-70 mph, very relaxing in 5th. I have done just about every mod you can think of and if I could only do one it would be the trans. It is virtually maintenance free and robust ,will probably out live most of us.

Cheers Phil

 

[Pythias]

I've never heard of anyone who did the Dastun conversion wishing they hadn't. It's easily reversible, as there are no changes to the frame. It could be undone anytime, with no marks showing that it had ever been changed, yet it is NEVER undone. What's that tell ya?

 

[nomad]

Well, I have a few spridgets and quite a bit of experience with the Datsun 5 speed but in my BE I have the ribcase and a 1275. Rear gears right now are 3.9 with 165/80 tires.
I need to replace the tires and will go with 155/80's. Since the BE is so light and I, like Nial, like the ribcase I'm fitting a 3.7.
I personally think your wife would be happy with that if she likes the ribcase anyway.
You can always dig up a 5 speed later if you are not happy with it. Probably won't make it a comfortable free way cruiser but, to me, a BE is most fun at the lower speed's anyway.
The modern trend seems to be a 6 speed and, though I like to stir my own, I'm having a hard time seeing where that is necessary.

Kurt.

 

[JPSmit]

Don't want to divert this thread - but, no 5 speed here - though I kind of wish I had. When I was doing Ms. Triss, I got to the point where every good idea was another $1000 (minimum) and 6 months - and I just wanted it done. And, while I usually wish I had another gear, in reality (except for the 50th at Road America) I don't drive far with the Midget - so, most of the time I really don't "need" the transmission.

So, both sides of the debate. But, now a question. You can buy a 3:55 rear end from Moss for about $600 - Is this a cost effective compromise?

 

[nomad]

JP, what rear end gears do you have now? I'm wondering if 3.55s might be a little high for getting started but they should give you about right high end cruise.

Just checked and there is a 210 5 speed on flea-bay for 1275!!

I'm sure they can be found for less but are getting hard to come by.

Kurt.

 

[nomad]

Mixed up my numbers....its $1250!!

Kurt.

 

[bug_sixty]

How ridiculous...... If you have time on your side just wait it out for some 210 junker around your area and offer to take it away for $___ pull the tranny and haul it down to the junk yard. A few years ago I caught a sign on such a deal at a Home Depot store... turned out the guy work at the store..... His car blew an engine on the way to work and he needed to just get rid of the problem quickly. Paid a two spot right there and had it out of the parking lot that day which was part of the deal... Years ago a buddy and I would go up and down back alleys on the first nice spring weekend of the year... the majority of residence would have their garage doors open.... Mostly looking for neglected or forgotten BE's or spridgets ....but you get the idea...

 

[RickB]

Mixed up my numbers....its $1250!!

Kurt.

Gee - I've been letting them go cheap!
Try setting up a RSS feed page and then do Craigslist searches for "Datsun 210" - scroll to the bottom of your search results and click the "RSS" link, it will them ask you where you want to send the RSS feed, point it to your reader of choice and then let them come to you.
Don't be afraid to buy the whole car, if it's a driver you can find a 4 speed to swap in, sell the car or use it and you get a 5 speed trans for cheap.

 

[RickB]

So, both sides of the debate. But, now a question. You can buy a 3:55 rear end from Moss for about $600 - Is this a cost effective compromise?

JP - just do the math.
If you have a 3.7 now then a 3.55 won't get you a lot - roughly 4%.
If you have the 3.9 then you'll get about 9% - so 4000 RPM becomes 3640 RPM - that would make a difference, and the 3.55 is far cheaper than the 210 transmission and the adapters / peripherals you have to buy.
Not to mention a LOT easier to install.
Also there is a good market out there for your used diff so you can recover a little of the cost.

 

[Gundy]

I just had to raise a hand for the sc/cr box. Loud...love the whine... And those
ratios are nifty. Don't know if they are durable but it is holding up to my tortures.
Shoot the wife once tried first gear for third after I made her wind it up. I've never seen my left arm and hand move like that. Automatic reflex .
Heck I love the 4.22 .
Just throwing in from the fringe.

 

[Keith_M]

This is an interesting discussion. I was completely unaware that the last two years of Midgets used a 3.7 rear end or that a 3.5 rear end is also available. I am now weighing the cost/benefit of the 3.7 or the 3.5 as compared to the 3.9 that I have. Has anyone had experience with the 3.5? I would think it might make the car a little less quick to accelerate in the lower gears.

I am also surprised at the importance of synchros in first gear. This has never really been an issue for me in my '65 Sprite (1275 and 3.9 rear end) or my Bt7. If I'm moving at all, I just shift to second instead of first; both engines have sufficient torque to allow smooth acceleration in second.