Gta v6 rebuild

Well I have now started my atmo rebuild and upgrades, The engine is now out and is surprisingly in really good condition, it was like new inside even the bearings look like they've just been put in. I have now hit my first problem. I have started the labourious process of porting the heads and I was wanting to put 46mm inlet valve's into the heads, however the 46mm valves seem hard to find as mega parts have them listed but have run out of stock as well as Simon auto and thay are not going to get any more in. Does anyone know where you can get some or a cross reference to a different engine. There is a valve maker are near me that will make them however the small quantity that I require they are pretty pricey does anyone want some 46mm valves, if I can get the numbers up then the price will come down a lot, or as they are being specially manufactured we can get them made any size we like.

[Alpineandy]

Have you asked Jon Law or Mr Faulks?

Thanks no I have not

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Thanks for the reply, yes g&s are good the old Aussie that owns it is well in to his valves, he made some for a 1935 trumph I had. If I am going to have some made everyone seems to have stuck to the 610 46mm becouse that's what was available off-the-shelf, but if it's an open book there seems to more space to put something bigger in is that possible, ie there is enough metal to put a bigger seat in.

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Well I have tried to Buy some from the normal suppliers and they say they are all out of stock and are not replacing. With the amount of work you have carried out on these engines you probably have a few more contacts than me. How much are you after for your heads that are already dun?
Stuart.

Well I decided to keep the standard inlets valves as I was concerned about valve clearance with the Pistons once the heads were planed. However the porting wasn't that bad a gob to do as the aluminium cut out very easily. Then had the heads planed and the valve seats cut back and angled.

Once the heads were of there was very little wear on the bores but thay were glazed, so I decided to remove the liners, Cleen out the water jacket and hone the bores, there was no sine of wear on any of the bearings at all which was a relief.
Once it was all reassembled I then had to machine of the top of the chain case down to the new head height. After this just down to the replacement of all the ancillaries and back into the frame.

After carrying out maintenance on the rear swingarms I decided to put the spax shockers on I had from the 610. It's now all back in the car and there is a marked improvement in the performance, however to get the best out of it the timing still the main issue, I was hoping to put the programmable system on from amethyst, however it turns out it will not cope with old fire engines. I then found another system which I thought was going to solve the problem from mallory but thay have gone out of business. The problem is this

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Yes I know I need to get it down to rolling road, however I have been trying to get it in roughly the right place I've been doing it the old school way with a vacuum gauge and driving, and noting the response I burnt a tank of fuel and it has been quite an interesting experiment. The engine has a holly conversion and the manifold is not heated, most articles say it should be between 30 and 36° Depending on the sparkplug location down to speed of Bern etc. I'm using manifold vacuum so I get 9° extra Advance and obviously when you put your foot down vacuum drops away. Doesn't seem to be a Middlepoint if you pull the timing back it goes like stink at the top end but at the bottom is not so good, and fuel economy is appalling. And if you advance it you get a good economy but obviously you lose the top end. This is why if you could get a programmable ignition I think it would be amazing plus the fact I've opened up the Inlet ports and the stock inlet manifold ports are now smaller than the head. So really a new inlet manifold needs to be made this would also mean that The carburettor could be mounted centrally on the manifold plus the Inlet ports would be of a more even length. At the moment the best setting which seems to get the middle road between top and bottom end is an advance of 34° flat out 43° on a cruise.

Well good day today, I had to go and get some paint for a two wheel machine and decided to take the alpine. Took the timing light and made probably only 1/2 a degree change, my god it's like I have fitted a v8 pulls like mad from 1200 right up to 6000 even spinning up the rear in 3rd on the old hard rubber, plus the fule gauge is not going down as fast. Working out the timing it seems to be 36 degrees which seems high but the odfire seems to be totally different to any other engine. Even the smell of the exhaust has that smell when petrol is burning right, no more tinkering

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Hi Martin bloody work gets in the way all the time, Well had a look it's clockwise I have also now done a mpg check average traffic fast mega foot down 24mpg worked of satellite not the speedo as thay are normally over read by 3/4 mph.