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5-Speed plus a 3.9 or stay with a 4.22

Bill, Eric on ahexp.com has a thread going on a Group Purchase for Speedhut to do a Custom Template. They used to do it but now want a lot of 20 to produce. Check their site if Tach and Speedo can do + Ground.
 
Both 1st and 2nd are lower in the datsun trans, but there is a pretty big jump to third. With a healthy 1275, stock flywheel, 3.9 and datsun 5 speed it is possible to start in 2nd gear with very little clutch slipping.
 
I have the Datsun 5 speed in two cars and the BMC 4 in my BE. I like them both! Think that after I go through the engine on the BE I will keep the stock trans and go to a 3.7 in the rear. The BE is light enough that I think 1'st will be just right and the jump to second won't be quite as quick. In my Datsun engined Midget I regularly go from 1'st to 3'rd to 5'th if I'm not in a hurry and the terrain is flat.

Kurt.
 
I like the 4.2 but also use a taller first gear. Sc/cr is noisy but man o man the spacing is super.
4K revs at 60 or so isn't really a problem when you redline is 7K . Noisy? Yes....especially with
a free flowing exhaust....just like I like it. 2nd and 3rd are sweet in the mountains.
I have a 3.7.... Stinks with my transmission.
It is not my daily driver however.
 
High folks,

With my 1275cc and about 100 hp I am planning to change my 3.9 into a 3.7 diff. Keeping 4 gears is keeping the car British..
 
Remind me what years the 3.9 was standard in spridgets?
 
Remind me what years the 3.9 was standard in spridgets?

Started in mid 1968 till 1978??? Not exactly sure when BL went to the 3.7 but I am sure on the start since I bought a 68 parts car and to clinch the deal I had to crawl under and check. I wanted a 3.9.

Kurt.
 
Started in mid 1968 till 1978??? Not exactly sure when BL went to the 3.7 but I am sure on the start since I bought a 68 parts car and to clinch the deal I had to crawl under and check. I wanted a 3.9.

Kurt.

The switch to a 3.7 did not occur until August '77. Introduction of the 3.9 was December '68
 
I recall Frank Clarici advocated the 4.2 with the 5 speed. I miss that guy, always good advice on every forum. :cheers: to Frank!

Personally with a built 1275/ribcase I've been wondering why I don't put the 4.2 back in... Probably going to. The fun power is further up in the rev range and 70mph is double most of the posted speed limits around here.
 
Gerard just sent me a note that my 5 speed kit, clutch kit, flywheel, and front tilt bracket shipped last Friday. Bugsy gets a new fun accessory soon. Yeah one worth waiting for. Thanks Gerard��
 
I recall Frank Clarici advocated the 4.2 with the 5 speed. I miss that guy, always good advice on every forum. :cheers: to Frank!

Personally with a built 1275/ribcase I've been wondering why I don't put the 4.2 back in... Probably going to. The fun power is further up in the rev range and 70mph is double most of the posted speed limits around here.

There's no right or wrong answer here... it's a matter of personal taste and driving preference. I like the 5 speed with a 3.9. A number of people like it with the 3.7, but I think it's completely unnecessary to to that low, as I think you sacrifice too much low end and you'll already be turning in around 3200 at 65 MPH. Others really want as much of the line "oomph" and stick with the 4:22. How much freeway driving is necessary in your locale will somewhat dictate to which extreme you want to go.
 
Gerard just sent me a note that my 5 speed kit, clutch kit, flywheel, and front tilt bracket shipped last Friday. Bugsy gets a new fun accessory soon. Yeah one worth waiting for. Thanks Gerard😊

Hi Jim,

Your box should arrive on Thursday. You'll have fun opening it.
 
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