GT6 Restoration

[DJB350Z]

Hello,

I'm Dom and after a long time of looking for a restoration project, last week I bought a Mk3 GT6. This is my first classic car, so I'm very much still learning! The car was bought as a restoration in 1997 from the previous owner of 10 years, and had a lot of bodywork carried out but things slowed down and now 25 years later I'm the new custodian.

The car has been completely stripped, and parts mixed up in various boxes with almost no labelling. I spent the best part of 2 days going through all of the bits and actually it looks quite complete, but there are some missing items (steering rack, indicator stalks etc.) and things that need replacing.

Body work wise it's really solid with lots of new panels welded in already but now it needs tidying, prepping and painting. Underneath is so clean.

The hurdle for me at the moment is identifying the engine. A 2.5 PI engine from a Triumph 2500 is what I have in front of me, and is what is registered on the V5. But, the cylinder head number indicates it's possibly not the original matching head. I'm trying to find out if the 2 are compatible, with an acceptable compression ratio before starting a rebuild. Otherwise, I'll need to consider other options - maybe sourcing a 2.0 GT6 engine or finding another compatible head.

Aside from that the differential looks like it's been overhauled (although no paperwork to back it up), and the gearbox bell housing looks like it's got a hole in it, D'oh.

Anyway, look forward to posting progress on the forum.

[Badwolf]

Hi Dom. Welcome to the madhouse. Don't fret about your storage system. My MkIV Spit was stripped and stored in exactly the same way. 30 odd years later I am still finding strange 'assembly methods'!!

Enjoy the forum, ask the questions, use the search facility. Don't be shy there are no stupid questions, we all had to learn and those like me will, continually, thanks to the wealth of knowledge, good will and talent here.

[Colin Lindsay]

Hi Dom, and welcome. 

Post away, both questions and progress; bear with us regarding thread drift and long-winded discussions but we usually get back to the topic at some stage. We have genuine experts on here and we all milk their brains daily.

By the way there ARE stupid questions, but usually, on this forum, nothing to do with Triumphs.

[JohnD]

Welcome, Dom!

This may help you work out what you have,  block vs head: https://www.goodparts.com/tr6-compression-ratio/     The head thickness is guide top the CR you may expect, but for e reliable calculation, only volumetric measurement will do!

And recall, late in the life of the GT6, Triumph fitted domed pistons to the  2L  engine ( from KE      10,001).     This allowed them to fit the same heads as were going on 2.5L TR6 and Saloon saloon engines.    Presumably, the time and cost of machining the heads from the same castings for the 2L was more than ordering special pistons.

John

[RichTeaBiscuit]

Hi Dom! Nothing to add but I look forward to reading how this develops 👍

[DJB350Z]

2 hours ago, JohnD said:

Welcome, Dom!

This may help you work out what you have,  block vs head: https://www.goodparts.com/tr6-compression-ratio/     The head thickness is guide top the CR you may expect, but for e reliable calculation, only volumetric measurement will do!

That link looks to be helpful! Will get out tomorrow to get a measurement of the head.

Thanks all for the warm welcome. I'll create a separate project thread soon.

[Stratton Jimmer]

Welcome to this place Dom. I have a mk3 GT6 and a Sixfire - Spit 1500 with a GT6 engine. Hybrids like this offer a whole new range of problems for their owners particularly when the conversion was done by a PO. Best of luck with your restoration.

[gt6j]

Alright Dom, just got a gt6 myself look forward to seeing progress on this and finding out how you get on. Good luck!

[Pete Lewis]

this is  from Chris witors site aimed at 2000/2500 saloons but does give some head identification clues that may help

head_applications_chart.pdf (chriswitor.com)

Pete