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All the discussion on transmission and differential changes have forced me to face some harsh realities . . . Where I live in order to get out of town there are only two choices; Freeway or miles of traffic clogged streets. Freeway speeds here outside of work hour traffic and accidents seldom flows less than 65 miles per hour and 70 to 75 miles per hour is the normal traffic flow speed any speed less than 60 and you create a dangerous traffic slow down and hazards as people pass you on any side there is an opening. Makes... MORE
"What's the sense of gearing these cars primarily for highway cruising?" Well.... 'Cause I didn't get a BE so I could leave it home in nice weather when I commuted down to NYC airports to fly the friendly skies in bascially 70mph limited access highway driving circumstances where having a 5 speed enables me to tune for low and mid-range instead of top end, as one might have to do with a 4 speed and 3.9. :):) All depends upon the driving circumstance, state of tune, spec., etc. Considering my engine spec in terms of torquey low and mid-range... MORE
"Spitfire O/D gearbox" Will this fit the Spridget tunnel, etc? Seems to me this came up before and I sort of got the impression it would not? Cap'n. Bob '60 :{) PilotRob@... 25194... MORE
that's why I added the 'roughly' qualifier! I have read different road test reports with hugely varying mph/1000rpm figures - by more than the diff ratio change! David "David Jacobs" 25184... MORE
Well, Stewart... If the modded 1275 pulls smoothly from idle to the degree you state, I don't see the problem then in terms of low end and clutch wear...I'd go with the 3.7 and see how you like it? Cap'n. Bob '60 :{) PilotRob@... 25193... MORE
The useless road engine was the cars original 948 motor.. that was a right screamer, and overheated in traffic all the time.. The Current one seems much happier, but as I said the result is it will not even notice going right round the rev counter and out the other side in 4th!. The modded 1275 does have a lumpy idle, but pulls cleanly from standstill, and can pull off from rest in 4th although this does require abuse of the clutch (but not as bad as you might think.) I believe my 1500 has a 3.9 diff so... MORE
The Spitfire O/D gearbox is a nice solution. You keep the standard ratios for back-road fun and get a cruising ratio too. And the very slick change achieved with the O/D selector switch makes for rapid and fun driving on fast twisty roads. Guy "Guy Weller" 25161... MORE
You can anticipate the changes by working it out in terms of percentages. Changing a 4.22 diff with a 3.9 diff is about a16% change. Revs in any gear for a particular road speed will reduce by 16%. Or road speed will increase by 16% for the same revs. In theory (but not in practice) acceleration will be worse by 16% which sounds a lot but is barely noticable. That said, acceleration changes are not quite so straightforward as it depends on how well the gearing is matched to your particular engine torque and power characteristics. And these depend... MORE
Stewart..... If your engine is tuned for the high end (and it certainly sounds this way.."useless road engine"...."lumpy idle"), then going to a 3.7 will make it more a useless road engine in terms of the low end. So...it you are using the car mostly at highway speeds (say, 3k or higher) than no problem. Town driving will become more of a hassle as you'll be at lower rpm more of the time at lower speeds, unless you retain lower gears more of the time then you are currently used to. The more available 3.9 might make for a... MORE
I want to put a coin box on it, and mount it on a pedestal in front of the local supermarket as an amusement ride? When you are retired on a fixed income one must come up with ingenious ways to support the spridget habit. :-) I was working out in the driveway yesterday and a fellow saw a couple of my spridgets and commented that he once had a collection of 13 Nash Metropolitans. Men and their one-up-man-ship. All I really want to do is mount my spare the engine and transmission back in my 69 parts car... MORE
You've successfully made every argument on the situation. Pick your poison...'-) The OD unit is probably the easiest and most practical. Your other option is to install a 1275 with a Datsun 5 speed. That's the best choice in my opinion. Easily done too. You could opt for all Datsun drive train too. Gerard "gerardchateau" 25154... MORE
I have a 3.9 matched with my 5 speed and personally I would not not the low end results with a 3.7. Some do like that combo, but what the sense of gearing these cars primarily for highway cruising? Might as weel drive the Volvo. Gerard "gerardchateau" 25151... MORE
Dear Listers, After tinkering with my '75 Midget all summer I finally have the beast to some standard of reliability having (knock on wood) cured the lean running problem. My next endeavor is to swap the Stromberg for a pair of SU's and to replace the clutch due to weak springs, I hope. I will probably lighten the flywheel while I'm at it. Since I will be pulling the engine anyway why not address the unsatisfactory gearbox as well. Running 4000 rpm at 65 mph doesn't sound good to me. Unfortunately the 1500 engine doesn't have a nice swap... MORE
could also be a bent clutch fork.. "Beckers" 25118... MORE
Nigel, Hmmm. 8/39, that would make it a 4.875:1 ratio and a new one on me. I see from the link David J. provided there really is such a thing. As David says, quick acceleration but soon high rev's. Stock Bugeyes and early Spridgets were 4:22, later Spridgets (post 68) were 3.9 and the last Midgets were 3.7. 4.55's were used in Morris Minors and loved by racers. Gerard "gerardchateau" 25140... MORE
Gerard Thank you, that was most helpful. It was an 8/39 which I guess is a ratio of 4.8 - is that good/bad? I'm afraid it doesn't really mean anything to me! Bearing in mind, these diff's were given to me by a guy who used to race Spridgets in the 60's. Thanks, Nigel "amukdigiphoto" 25136... MORE
Hi guys I was given a couple of Spridget differentials recently, but I can't seem to figure out what ratio's they are. Does anyone know if there are any identifying marks on diff's to indicate what ratio they are? Thanks in advance. Nigel "amukdigiphoto" 25126... MORE
Don't know. The car was not driven for almost a year and I do not know what all the PO did to it. The guy I bought it from bought it running, drove it home and a couple of times around the block, did some work on the battery pan, put in a new radiator and hoses then got too busy at his job to do more so never took it off the no-op license and let it sit for almost a year, then when he tried to drive before selling it discovered he could not get it into... MORE
Don, Have you watched underneath to see if you have enough travel on the slave cylinder pushrod while someone else depresses the clutch? You may have air in the line or perhaps your TO bearing is worn down to nothing (or worse*). Another possibility is a worn pivot on the clutch fork. You should feel the kind of movement (wiggle) and freeplay (travel) you have in the clutch fork while the engine is off. *I picked up a '71 once where the TO was worn down so far, it actually fell off the clutch fork when I wiggled it.... MORE
Not correct according to my source. This information is from the Chilton's Nissan 210/1200 repair manual. 1974 B210 Sedan and Coupe- A13 1975 B210 Sedan and Coupe- A14 1976-78 B210- A14 1979-81 210, 210 MPG -A15 The book goes on to discuss A series into 1982 models, but the question was about A series engines. A-series engine were used in the 210, B210 and 1200 Nissans. beginning from 1973. These include A12, A12A, A13, A14, A15. The A12 is considerered to be very disirable because it is the least choked and detuned due to SMOG restrictions and it has... MORE
Hi David, The engine mounting plate is identical to the Spridgets as are the rubber mounts. Because the frame is completely different in the Morris, the frame to rubber mount bracket is completely different. The Datsun engine has the motor mounts near midway in the block, so new mounting points to the frame are required. Also, they are not symetrical like the Spridgets, so two differnt length frame mounts are necessary. Paul A. makes the motor mounts and so there was no need to reinvent the wheel. I just purchased them from him. Placement is a matter of position... MORE
Went to the DMV and took my Purple 73 rwa off non-op today then took it out for its first freeway speed run. Was hoping a good run would cure my transmission problem I posted about before . . . can start it in first and reverse and runs fine in first and reverse, however once I drive and shift up to second and above then stop I cannot get it back into first or reverse . . . gears grind (yes, I do shift into second first, then try first) I do not want to force for fear... MORE
I'm still trying to put a Datsun/Nissan A14 engine/5spd tranny in a 71 Midget. I have seen pictures of one in a 76 or 77. It looks like it comes from the factory. The Datsun engine seems to be an almost direct copy of the Spitfire engine, but with improvements: 5 main bearings, good oil seals front and rear thrust bearings integral with main bearing(it won't fall out!), aluminum head with great intake ports, etc. The 5 spd tranny is butter smooth and quiet. May not get you the horsepower a RX7 will get but it can produce 100+... MORE
You can certainly put a RX7 rotary in a Midget, but you'd better put in the RX7 trans too. There'll be a lot of parts which will have to be fabricated - exhaust, guage hook-ups, cooling, etc, etc, etc. You'll then have a car which will go faster than either the suspension or brakes can safely handle. I'd suggest you just sell the Midget and buy a RX7. "Jeffrey Holmes" 25076... MORE
if he does, you could turn the engine 90 degrees, and then run a drive belt from the engine to the skateboard wheels - think of the power to weight ratio! "David Jacobs" 25074... MORE
