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Major Modifications done to this 1978

Select the headers below for more information on that particlular subject.

J-Type Overdrive and Gearbox swap
When I found the Mk III a few years after getting my car, it had in it a 1500 engine and J-Type Overdrive, plus it came with another J-Type and gearbox beside it.
A relatively painless disassembly, cleaning, a few new parts, reassembly and installation gave me much better RPM on the highway (~800 less).
GT6 Differential - Not really a major modification, but significant none-the-less.
Although the 1500s destined for Canada had the 3.63:1 differentials, when I learned of the 3.27:1 ratio in the GT6 I was eager to try it out.  I spend a lot of time cruising and came to really hate the screaming 1500 and knew those highway miles were not helping its longevity.
Those 3.27 gears took my RPM down another 300 at 115 kph, so now I was cruising at around 2800 RPM and making good time. :)
Some have mentioned that the lower gears make the car a real dog; I totally disagree, a decent condition 1500 makes plenty of torque and handles the change nicely.  Because of the relatively short first and second gears, it was still great fun on the AutoCross courses.
I think this modification may become popular, so I recently acquired a back-up diff in case something unfortunate should happen to mine.
New Bolt Pattern and Modern Wheels - Certainly one of the biggest aesthetic transformations on the car.
This modification virtually eliminated the front end shake I was getting on the highway.  Granted some or even all of that could have just been from old tires and coming out of balance with wear.
With my already lowered Gear Ratios I was not interested in changing the circumference of the tires just looking for better tire selection, better performance, and a more modern and unique look.
Minilight-style wheels are available for our 4 x 3 3/4" bolt pattern, but everyone has them and although period correct etc. etc. their appeal has been completely lost in the crowd.
Also, I have seen select few Spitfires / GT6s with correct offset for those wheels.  The fronts almost always stick out too far because guys don't select correct offset distinctive for front and back.  I killed a couple birds with this stone; perfect offset front and back and rotatable.
 
 
 
 
 
 
 
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