Opening up a 202 head
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- Minor Friendly
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Opening up a 202 head
Got a couple of spare 1098 heads kicking about and have decided to have a go at improving one (a la David Vizard's interesting book) so I need a die grinder...prob. mains electric (my compressor good for paint but runs out of breath with rotary tools) anybody found a good one? The main target is opening up the cylinder head around the valves a little to improve air flow, the ports themselves just need a bit of smoothing apparently.
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- Minor Fan
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Re: Opening up a 202 head
I did the same many years ago when I overhaled the engine. I followed the book but did not go the full hog. One thing I did do was open up the carburetted in the way he suggests, from round to square bore and feather the throttle disk etc. Every thing went smoothly and the car runs OK. I can't say that it dramatically improved things or produced more power but the engine seems to run smoother. Good luck with your project.
1969 Traveller in Almond green. Owned since 1979.
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- Minor Friendly
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Re: Opening up a 202 head
Yes I might not go the whole hog either. Bigger inlet valves would prob. make a big difference but then there's a trade off with fuel economy.King Kenny wrote: ↑Fri Apr 05, 2024 8:00 pm I did the same many years ago when I overhaled the engine. I followed the book but did not go the full hog.
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Re: Opening up a 202 head
After reading some bad reviews re: longevity of electrical grinders, think I'll prob. go back to air, also more choice, including 90degree beasties which i think would be easier to handle. Anybody used one of these for carving cast iron?
https://ffx.co.uk/products/draper-drape ... der-117022
https://ffx.co.uk/products/draper-drape ... der-117022
Re: Opening up a 202 head
Hope the modifications go to plan, on a personal note, and it’s just my view, it’s not worth it !
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- Minor Maniac
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Re: Opening up a 202 head
I have to agree with Les.
If you want improvement - source a 12G295 head, skim 0.060" from the head face and you have a very good and efficient head without having to do much work.
The down side of the 12G295 head is the price.
Saying that here is a 12G295 head going cheap (at the moment)
https://www.ebay.co.uk/itm/135038889336 ... Sw0HlmL5Qz
I would suggest that a straight grinder would be better than a right angle grinder.
My cheap and cheerful WorkZone 135W combi tool/mini grinder is more than adequate for re-shaping cast iron cylinder heads.
If you want improvement - source a 12G295 head, skim 0.060" from the head face and you have a very good and efficient head without having to do much work.
The down side of the 12G295 head is the price.
Saying that here is a 12G295 head going cheap (at the moment)
https://www.ebay.co.uk/itm/135038889336 ... Sw0HlmL5Qz
I would suggest that a straight grinder would be better than a right angle grinder.
My cheap and cheerful WorkZone 135W combi tool/mini grinder is more than adequate for re-shaping cast iron cylinder heads.
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Re: Opening up a 202 head
Cheers folks, some good advice there.
I'm just a bit curious as to what could be got out of the 202 head, probably not a lot, but I've got a good inlet m'fold, lcb and a cooper cam so I've got the basis to get enough out for a more interesting drive hopefully without upsetting my reground 60 year old crank? Perhaps needs another think, there are other jobs that need attention 🫣
I'm just a bit curious as to what could be got out of the 202 head, probably not a lot, but I've got a good inlet m'fold, lcb and a cooper cam so I've got the basis to get enough out for a more interesting drive hopefully without upsetting my reground 60 year old crank? Perhaps needs another think, there are other jobs that need attention 🫣
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- Minor Legend
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Re: Opening up a 202 head
You could " blueprint" the head to manifold , I'm sure gasflow doesn't like those steps...
John ;-)
John ;-)
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Re: Opening up a 202 head
I suspect that you have put the above as an example but I notice that the head in the above photo is not a 202 item and you have removed the manifold locating rings which are there to line up the manifolds and so aid gas flow.
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Re: Opening up a 202 head
Yes, you're right...that's one of the things that might help. Quite an interesting project, thinking I might save it for the autumn/winter and make the most of the weather now (paintwork ). Putting in slightly larger valves is another possibility...but I don't have the facilities to attempt anything like that in the near future.
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Re: Opening up a 202 head
Correct, it's a 12G940 , but just look at the steps , whoppers on the heads exhaust side of things...not just the inlets.philthehill wrote: ↑Wed May 01, 2024 8:08 am I suspect that you have put the above as an example but I notice that the head in the above photo is not a 202 item and you have removed the manifold locating rings which are there to line up the manifolds and so aid gas flow.
John ;-)