Alan Cochrane Posted May 4, 2014 Report Share Posted May 4, 2014 Hi Everyone I'm going to start my 250 resto project this Summer and thoughts turned to the engine. I'm going to upgrade it to TR5 spec and so was wondering what the full list of mods I'll need to make. I've already got:- NOS 2500 UK spec cylinder head Complete PI system and most importantly of all, an alloy rocker cover! So l'll need to change-the camshaft and the dizzy obviously, but what else. The cylinder head came without valves,rocker shaft or pushrods, so I'm not sure if any of the 250s head can be swapped over. Cheers Alan Quote Link to post Share on other sites
pfenlon Posted May 4, 2014 Report Share Posted May 4, 2014 Hi Everyone I'm going to start my 250 resto project this Summer and thoughts turned to the engine. I'm going to upgrade it to TR5 spec and so was wondering what the full list of mods I'll need to make. I've already got:- NOS 2500 UK spec cylinder head Complete PI system and most importantly of all, an alloy rocker cover! So l'll need to change-the camshaft and the dizzy obviously, but what else. The cylinder head came without valves,rocker shaft or pushrods, so I'm not sure if any of the 250s head can be swapped over. Cheers Alan seems your almost there Alan, my memory cells aren't what they were but I found a 2500S head when I did the change over on my 250, which was said to be the better one but who knows. I got a cam from this forum too, best of luck with it. Quote Link to post Share on other sites
Guest ntc Posted May 4, 2014 Report Share Posted May 4, 2014 Alan You need to say what casting and stamped numbers are on the head also how thick it is. Quote Link to post Share on other sites
Alec Pringle Posted May 4, 2014 Report Share Posted May 4, 2014 Hi Alan, presumably your nos head is one or another saloon variant - in which case perhaps the best thing you could do is to despatch it to Peter Burgess and let him do a sensible job for sensible money, then you might have some chance of achieving the mythical 150 horses . . . . . Cheers Alec Quote Link to post Share on other sites
Andy Moltu Posted May 5, 2014 Report Share Posted May 5, 2014 You might need an exhaust manifold (unless you are going for a tubular one) - some of the US spec heads had different port spacing to most European (and for that matter US spec cars) Quote Link to post Share on other sites
Alan Cochrane Posted May 5, 2014 Author Report Share Posted May 5, 2014 Thanks for all the replies. I'm going to have the head reworked to take unleaded petrol so your recommendation is much appreciated Alec. Maybe I can achieve the magic 150. The head was still in it's original Stanpart box when it arrived. The PO had lathered it in grease, so it was like new underneath. I'm thinking of having it gas flowed to the old stage 2 level- is it still called that and matching it with a fast road cam. I tried this combo in my GT6 many years ago and would recommend it to anyone contemplating a rebuild. Still not sure about the interchangeability of the valve gear though- can anyone clarify please? I know there is more than one length of pushrod available. I'm popping down to the lockup later so I'll get the serial number then. I'm planning to fit a full stainless steel exhaust system. It makes economic sense in the long run. I used to have to change the GT6s back boxes every 2-3 years due to trapped moisture perforating the pipes immediately behind them. A common problem with classics that hibernate for the Winter. 12 years down the line and the stainless system looks as good as new. Cheers Alan Quote Link to post Share on other sites
Alan Cochrane Posted May 5, 2014 Author Report Share Posted May 5, 2014 Hello again It's May Day so plenty time to think. The 250 engine ran at a much lower CR than the 5. I'm assuming that this was due to the US spec head and not the block who's internals are identical to the 5? Cheers Alan Quote Link to post Share on other sites
Alec Pringle Posted May 5, 2014 Report Share Posted May 5, 2014 Hi Alan, yes it's the head that differs. Peter Burgess has reworked several nos heads for me, on behalf of friends overseas, I've been impressed with his work and with the value for money. Fast road heads for want of a better description, and in your position I'd be asking him to do a proper job complete with his valves and springs - you might wish to ask for advice about cams from some of the regulars on here. Ditto exhausts.Then you'd be wise to get the dissie to Martin Jay for rebuilding to match the engine. Cheers Alec Quote Link to post Share on other sites
Tom Fremont Posted May 5, 2014 Report Share Posted May 5, 2014 Head thickness difference is circa 1/16" between TR250 and P.I. Inlet port spacing is different but exhaust is the same. Valve gear is interchangeable as the head height variation can be compensated by the rocker adjustment provision. In short, you're good to go with what you have or will soon acquire. These NOS heads keep coming out of the woodwork! Quote Link to post Share on other sites
Alan Cochrane Posted May 5, 2014 Author Report Share Posted May 5, 2014 Thanks again for the recommendations. I think it would be wise to fit new valves, springs and rocker shaft as a matter of course. I've no idea what state they're in at the moment but judging by the rest of the car not good is probably the answer! Alec Do you have contact details for Peter Burgess & Martin Jay? Cheers Alan Quote Link to post Share on other sites
stuart Posted May 5, 2014 Report Share Posted May 5, 2014 Here you go. http://www.mg-cars.org.uk/peterburgess/ http://www.distributordoctor.com/ Stuart. Quote Link to post Share on other sites
Alan Cochrane Posted May 5, 2014 Author Report Share Posted May 5, 2014 Thanks Stuart Quote Link to post Share on other sites
Richard71 Posted May 6, 2014 Report Share Posted May 6, 2014 Hi Alan, I notice you're from Kirkaldy, it's a shame you weren't undertaking this project some years ago as I recall visiting some chap's premises in the shadow of Raith Rovers stadium who had a Triumph graveyard. 20yrs ago my boss sent me in while I was in the area to collect some parts for a GT6 I think. I happened to be working in Kirkaldy today and curiosity got the better of me, seems that somewhere in the last two decades he's moved on and property developers have moved in......surprise surprise. I'm sure you got have got yourself all of what you needed from him. Can't remember the name of the company, do you? Richard. Quote Link to post Share on other sites
Alan Cochrane Posted May 6, 2014 Author Report Share Posted May 6, 2014 Richard Yes that would be Chic Doig who's now moved up to a wee village north of Kirkcaldy called Cardenden. I'm still a frequent visitor after 28years of Triumph ownership. I bought my GT6 from him in 1986 fort £1200. If you check out EBay you'll see he sells lot's of.stuff at quite reasonable prices. The sale items are always pictured lying on his headed notepaper. Let me know if you're coming back to the Kingdom. Alan Quote Link to post Share on other sites
Richard71 Posted May 6, 2014 Report Share Posted May 6, 2014 Hi Alan, I am familiar with the name Chic Doig and fairly certain I've bought from him via eBay, just never made the connection with him to Kirkaldy. I'm in Fife fairly often though I think today was the first I've set foot in Kirkaldy in donkey's. I'll drop you a line next time I'm in the area and if we both have time I'll come have a gander at your 6. Cheers! Quote Link to post Share on other sites
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