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Re: (Nissan) What about the bellhousing?

To: chapman-era@Autox.Team.Net
Subject: Re: (Nissan) What about the bellhousing?
From: Keith Gustafson <gusmach@shore.net>
Date: Mon, 8 Sep 1997 11:23:26 -0400 (EDT)
>>Which shift pattern is it?
Regular 5th and reverse to the right

>Well, I forgot to ask about your plans for dealing with the bellhousing.  
>Is this one of the integral bellhousing models?  If so, are you hoping 
>to handle it by making an adapter plate, that goes between block and 
>bellhousing?

Well, since I posted this I have dis assembled the tranny and tried to fit
it to a chassis. the world famous Dave Comeau has several standard and one
spyder chassis in his attic. His spyder is 10+ years old[talk about your
long projects]and I was kind of depressed because one of the diagonal braces
interferes with a piece of the casting. In my spyder[ having been under it
fixing my jackshaft] that frame member is 'flattened', but it still poses a
problem. I may have to cut away the offending piece of casting. Behind it[
passenger side ~21 inches from bellhousing flange] are the ends of the three
shifter rails that the long extension rail chooses when you shift.I can
probably shorten them 1/4" and grind the outside of the selector tabs[making
up terms as I go along]. At this point in the chassis, it is widening and I
don't need too much to clear, once I shift the wide spot forward. 

The bellhousing is larger than the stock one and integral; if I can tolerate
the added length[see above], then I will just make an adapter plate. if not,
I may torch the thing off and adapt the ford one, but that makes even more
problems, plus the nissan has the slave cylinder on the opposite side so no
more heat problems.

For the shifter, it will work out well. The finger that selects the rods is
fixed to the extension shaft at very nearly the exact spot needed to put the
new shifter. The only complication is that while the Lotus shifter is
'mirrored', the nissan shifter is 'half mirrored'. The nissan is direct
acting side to side, but reversed in front to back. If it wasn't so I could
probably cut a hole in the top and bolt the Lotus shifter on top! Actually,
that could be possible with a modified Lotus piece, hmm.....

As for the ratios, my calculations tell me that the difference between
nissan 1st gear and Lotus 1st is 1.3 mph at 6500 rpm [assuming 19.8mph at
1000 rpm in 4th with a 3.77 final drive]. Although 2nd is taller[1.858 vs.
2.0] having a larger gap here is easier to deal with because you have more
available torque in second and it pushes 2-3 and 3-4 a little closer, where
you need it.I am not looking for a racing tranny, as some on the list are,
just a good replacement with the bonus of a tall 5th.

 BTW, another calculation tells me that if you kept the final drive
numerically under 4.4, you wouldn't have to shift from 4 to5 until around
100mph, at which most normal twinks are a bit out of juice, and 5th would
still be quite a bit taller than 4th in the stock tranny. you could have an
autocross screamer and highway cruiser all in one!


wow, there's one for the byte count


Keith "don't get me going" Gustafson


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