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5 speed alternatives.

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58Custom

58Custom

Jedi Warrior
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I am in the planning stages of my eventual Midget rebuild. Mo Powah is high on the list. I have decided to keep a hipo A-series rebuild as an option. It kinda depends on if I find an a15/5speed before I start the build. This will be a car that will be driven hard in the hills and canyons of LA County and PCH.

I want somewhere around 100HP from whatever engine I build. An A15 would have no problem with this, a 1380 could do it and it's still the "right" engine. The Duratec idea has been abandoned. Sort of. Maybe. Nah. Well...

Anyways, I am wondering what OD alternatives I would have to the Datsun 5 speed. I want to have a list so that if I find any one of them first I can snap it up.

Is a ribcage with the factory OD OK for fast road service? What other options? I have my pencil ready...
 
Type 9 Tranny out of a Ford Sierra is also an option. That's what is done over the pond as Datsuns as we know them did not exist over there. You could also go Miata powertrain ala The Mite if you have not seen it.From Aus they are using Toyota Tranny's with a Toyota Powerplant. All sorts of options, all depends on how good an engineer you are and how good you are with a welder. The A15 Option with tranny is probably the easiest fit since it was modeled after an A series engine and physical dimensions are pretty close to the same. I think even the motor mounts bolt right up.

Remember, the power needs to get to the back wheels and there is a limit to what the stock rear end will handle without breaking halfshafts.
 
When using the A-series engine, the two options that have all the bugs already worked out are the T-9 (kits from Mo%$ and others) as Jim says or the MorrisService/Rivergate Datsun. I understand that in Australia there is a kit for a Toyota but that model of Toyota didn't make it to these shores. As far as power goes, the problem with using other than the A-series is WEIGHT. Change the amount over the front wheels and the handling characteristics that are the reason we live/breathe/and eat for the these "antiques" are quickly altered, not for the better. The Supercharger (again from Mo#$)seems like a great option for getting the power you want?
 
I should have at least 80hp out of my 1275 build (limit being the lower octane gas around here, could easily have pushed it higher but needed to keep the compression ratio down):

https://www.drooartz.com/index.php?page=44.3

I'm sticking with a ribcase 4-speed with a 3.90 rear end. Should allow cruising in the 60-70 range, which is plenty for my use. I want a more vintage feel, so I'm sticking with BMC parts.

Quite a few folks here have done the Datsun swap, it seems to be the simplest with the least modifications to the car. Hap (ACME Speed Shop, he built my motor) sells the T-9 kit as well, which does require a few mods but is, as mentioned above, well sorted.
 
The T9 trans is a tough trans. Probably stonger than a datsun. Don't forget the 4AGE toyota motor and trans out of a supra if I remember correctly. Far more power than you are looking for in a tiny power plant. Also mazda rotary. There are guys on this list that are doing or have done all of the above.BTW the A15 datsun motor mount on the left side can be used the other has to be fabricated as does a remote oil filter setup and intake manifold if you want to keep everything under the bonnet. Pan or frame mods as well.
KA.
 
Also -

If you are looking at the Datsun A15 then try to find a GX head.
You can get side draft intakes and put on SU's or side draft webers.
With the GX you can pretty easily move up beyond 130 hp.
The lump is about the same size as the BMC 1500 but IIRC it is a little lighter.
It's built better and stronger, they licensed the design then improved it.
Yes the passenger side mount has to be changed and the front needs a bit of a cutout for the front of the pan.
 
Rick, just the common mid 70's B210 head and cam should get him somewhere around 90 hp. If you find a bunch of old datsuns tha stuff will be there. I agree though that GX stuff would be the ultimate barring the 4AGE swap. That swap is good for 160hp non boosted if memory serve's.
KA.
 
I didn't know the A15 was an A series clone. I'm gonna have to start looking fer one.
 
Well, it isn't a 5 speed. It has no overdrive. It's noisy as all get out. It is fun to use. A straight cut, close ratio, gear
set for the ribcase tranny isn't for everyone but it can be an option. Makes for a pretty strong gearbox. Nice for autocross or twisties. Not cheap.
Like another mentioned. Beef up those axles.


Sprigetmania sells 'em.

https://www.spridgetmania.com/web/Item/C-AJJ3319/InvDetail.cfm

They also sell whole boxes with the gears too.

https://www.spridgetmania.com/web/Item/C-AJJ3319/C/InvDetail.cfm
 
My stock A15 with the economy head and the stock downdraft carb gets me to 90mph too quickly. :devilgrin:
 
Question to the 5-speed guy's (running with a 1275).
What modifications to the body or any other mounting points need to be preformed to install a Datsun 5-speed? Is there anything, anything at all?
Dug
 
Dug: No, just lay down the cash and rivergate or morris service has done everything but the install.
KA.
 
Tom: There was'nt a OD for the ribcase box that I'm aware of that was available to the public. The triumph box fitted to the late 1500 midget's had a OD but I don't know if it will fit a spridget. I'm curious to that as well. Anyone?
KA.
 
I don't believe there was ever an OD unit to go with the early tranny! I would love to learn if there are any that fit/would work!
 
nomad said:
Tom: There was'nt a OD for the ribcase box that I'm aware of that was available to the public. The triumph box fitted to the late 1500 midget's had a OD but I don't know if it will fit a spridget. I'm curious to that as well. Anyone?
KA.
Click to expand...
The Spitfire 1500 trannys that used a Laycock J-type overdrive will fit, with "minor" modifications. The inspection port will have to be opened out to the crossmember, and the crossmember cut out under the tunnel. The tunnel will have to be bellied out slightly from the inside using a scissor jack. Then the crossmember will have to be re-inforced lower down, or a removable subframe that bolts in will have to be fabricated. (There are some good webpages that show the process; many people have done it before. I plan to, as soon as I find a good affordable OD tranny.)
 
nomad said:
Tom: There was'nt a OD for the ribcase box that I'm aware of that was available to the public. The triumph box fitted to the late 1500 midget's had a OD but I don't know if it will fit a spridget. I'm curious to that as well. Anyone?
KA.
Click to expand...

OK. I once saw an OD for an MGB in the junkyard (that someone had messed up) and wondered if there was an OD ribcase. I hate that non-synchro first gear anyways. I'm a long-time Ford Toploader user and am used to have any darn gear I want when I want it.

The easiest option for me is an A15/5 speed. I know this. But I was flirting with the idea of a robust 1380 build just for fun. I'll just go back and stick with the A15/5 speed idea. It really is the simplest.

Thanks to all for the responses. It does help to test your decisions from time to time.
 
The easiest option for me is an A15/5 speed. I know this. But I was flirting with the idea of a robust 1380 build just for fun.

Thanks to all for the responses. It does help to test your decisions from time to time. [/quote]

Good luck with the A15/5. Sounds like a hot setup.
I LOVE my robust 1380. It's more fun than a barrel of monkeys.
I find I rarely use 1st except for starts and close gear sets
means for most road use the 2nd is as low as I go once rolling.
In a pinch you CAN get first without a full stop by matching revs and a little double clutching.

Kim is right about the diff ratios working like an overdrive.
I went the other route and stuck the 4.22 back in my BE instead of the 3.7 one. Without an increased rev range the poor old thing would be redlined at 65 mph.

A 5 speed box would be VERY nice. I suspect the 1st gear is a granny gear which should make jack rabbit starts a lot of fun
and you'd still get the OD you are looking for.
 
I'm a dealer for the T9 5 speed conversions, and I sell mostly MGB T9 kits, for the MGB this is great option, it require no mods, and use 100% MGB flywheel and clutch components, however with that being said the kit is available for the Midget, but require crossmember and trans tunnel mods, so it nothing I ever pushed and I personally feel the Rivergate/Morris conversion are more Spridget friendly, the good thing about the Borg Warner T9 is every internal part is avaialable, and this is not the case for the Datsun gearboxes, but all in all the Datsun gearbox is excellent choice for the Spridget. Kim mentioned diff ratio and he has a fairly rare ratio in his, that lets him cruise quite comfortably, this or a 3.7 can be a alternative to a 5 speed gearbox, it's all about what you are doing with your car, Like David's car with it SC/CR gearbox, the SC gears do have a whine to them, that some folks would not like, but the gears are much stronger, but when it comes to screaming up the in the Mountains, David's gearbox is weapon, it's all about what you want.
 
Hap Waldrop said:
Kim mentioned diff ratio and he has a fairly rare ratio in his, that lets him cruise quite comfortably, this or a 3.7 can be a alternative to a 5 speed gearbox,
Click to expand...

What's he got, the 3.55 VB offered a while back?
 
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