Triumph Spitfire Overdrive Conversion

Triumph Spitfire Overdrive Conversion

Author
Discussion

peterjfox

Original Poster:

17 posts

6 months

Friday 26th February
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Anyone had a 1500 Spitfire Overdrive conversion recently?
Any idea of price recommendations?
Thanks

Spitfire2

1,835 posts

153 months

Saturday 27th February
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The price of exchange boxes and overdrive units has gone up a lot in recent years so I expect converting from a regular 4 speed will be a hefty price.

Might be looking for an exchange gearbox for mine soon as I've chipped a tooth in first. Although 2 gearboxes ago I lived with the same first gear tapping away for about 6 years .......

Yertis

16,221 posts

233 months

Sunday 28th February
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There’s the electrical side to consider too. I think if I was in your shoes I’d be exploring the five-speed ‘box alternatives, for simplicity and longevity.

hilly10

5,877 posts

195 months

Sunday 28th February
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Yertis said:
There’s the electrical side to consider too. I think if I was in your shoes I’d be exploring the five-speed ‘box alternatives, for simplicity and longevity.
Ditto that’s what I would do

//j17

3,704 posts

190 months

Monday 1st March
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A lot depends on if you can find a conversion kit/cheap 1500 O/D gearbox on eBay, etc.

None online at the moment but the £2,300 cost of a Frontline 5 speed kit gives you a good budget for a second hand box + other bits (rear mount, prop., Speedo cable and angle drive, some wire).

And with a 1500 Spitfire you're talking about a J-Type overdrive so the electrics are simple.

tapkaJohnD

1,610 posts

171 months

Monday 1st March
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Similar thread here, two years ago, found that Mike Papworth was the man to talk to: https://www.pistonheads.com/gassing/topic.asp?h=0&...

The other gearbox guru is Tony Lindsey-Dean. Bioth are so busy and sought-after that they don't bother with a website, but Mike's contac is on that other thread, and Tony appears on Facebook.

John

caziques

2,009 posts

135 months

Saturday 6th March
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In 1975, Triumph switched to single rail gearboxes for the Spitfire 1500 and Dolomite 1300/1500/1850.

Making an overdrive version of the single rail box was quite complex, there are all sorts of different parts, whereas a three rail gearbox is relatively straightforward to convert to overdrive.

A car fitted with overdrive is so much better than one without.

It looks like the three rail overdrive adaptor plate (part number 313085) is still available - a D or J type overdrive can use this plate.

//j17

3,704 posts

190 months

Tuesday 9th March
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caziques said:
Making an overdrive version of the single rail box was quite complex, there are all sorts of different parts, whereas a three rail gearbox is relatively straightforward to convert to overdrive.
...
It looks like the three rail overdrive adaptor plate (part number 313085) is still available - a D or J type overdrive can use this plate.
Umm, it's no more or less complicated to convert either a single or three rail gearbox to overdrive - but it's generally easier to get hold of a second hand single rail o/d box, which is the way to go - trying to convert your current 'box means laying your hands on everything from an o/d mainshaft rearwards (RKC767 for a single rail/TKC923 for a 3-rail with D-type/TKC899 for a 3-rail with J-type).