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Discussion Starter #1 (Edited)
I've been thinking about a rebuilding a head for my spider for a few months now, finally got round to buying 1.
I plan to get the ports gas flowed but keep the rest standard!
Can any body give me some advice please as I'm in new territory!
What's the best way to clean the valves?
I understand all the gubbins that go with each valve has to go back in the same order taken out?

Thanks Andy
 

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Yes, you must keep all the parts together and put them back in the same place. As for cleaning the valves, lapping them in obviously cleans the seat but depending on how much build up there is, you have to be quite harsh, scraping and abrasive wire wheel I used (before having to replace them all as they were all bent :lol:)
 

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Discussion Starter #3
Cheers Mitch! I had a look for the project thread you did but couldn't find it. Now I see you have a link on you post :lol: I remember you rebuilt the head and probably have some good info there ;) Would you recommend replacing any part/parts in the rebuild?
 

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Discussion Starter #4 (Edited)
Heads stripped down studs as well. Everything labelled and bagged up. Pics of course! carbon exhaust build up and cleaned.
There seems to be a slight lip on the exhaust manifold side of the head, filed a bit back to show improvement. (last pic, filed bit on the left)
Should this lip slow down exhaust gasses leaving the head?? Mass produced heads will have imperfections so tiding up by hand should see improvements???
 

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Wikipedia cylinder head porting..

it's a good read..

Especially.. the.. 'porting and polishing myth' section..
 

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Your right it was a good read! ........confused.com :lol:
Ha Ha.. interesting isnt it.. goes back a long way when most production cylinder heads were.. well ..crap.. over head valve heads..
anyway everybody set about trying to make them better by grinding and polishing.. eventually a few switched on guys using a thing called an 'air flow bench' discovered.. like a lot of things in the tuning world that 'what looks good aint necessarily good'..
it was recognised that polishing not only was a complete waste of time but it had a detrimental effect.. also any work in the exhaust ports was also a waste of time..inlet side could be improved if you knew what you were doing..
To be honest these cylinder heads are pretty damn good from the factory.. but a bit of a clean up wouldn't do any harm..
in fact the main reason for having two camshafts is to keep the inlet and exhaust tracts as straight as possible.. if you look at your photo you can see straight through.. which is good.. :)
 

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Discussion Starter #10
Cheers for taking the time out to share that! This forum is full of great characters with good advice :thumbs:
 

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Discussion Starter #13 (Edited)
The most time consuming part I found was putting the collets back onto the valve stems.
The rebuild was most enjoyable tho :D
Cost all of £110 including the head.
£75 head
£30 skim
£5 valve grinding paste
 
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