gengis

I don't mind going a bigger cam, I have had the 72 for over 5 years and the car never rev's under 3500 as it is a track car only... If I end up doing the bottom end eg just a clean up then I would feel better about going passed the 6500 which I short shift at now as I had the age of engine in mind...

That makes sense, I did not think of the under side of the lobe... Thanks to every body for their suggestion. I will let you know how I go... Keep well, Gengis

All good advice, Thanks heaps, So I will just shave the minimum off the head to ensure no warping, the compression will go up a little it will have to do as I see the knock on effect of adding would need to be done to raise compression considerably. I have just been to a cam regrind shop, they informed me that they could re grind my existing cam which they say is a 72 after I gave them the 487 number stamped on the end. They can grind it to a 74. I am not sure how they can do this? Don't they need to add to the cam lobe in order for the valve to open longer thus more fuel go's in etc... to add Duration etc... I am no expert but I did ask them if they add to the cam however they said they did not but would regrind mine... Am I wrong here and should I go to another shop or are they telling me the truth?

Thanks for the advice, At what compression ration is to high to run on 98 at the pump fuel... I was thinking to increase the compression to 10 to 1. And how much would be needed to shave of the head to achieve this. Or is this something they would know at the machine shop?

The head has never been off. So it has never been shaved. Great news about Clive cams, I will look them up and see if they can provide another cam perhaps one jump up. I did read the post about chain tensioner earlier thanks for that. I will change the head gasket as suggested thanks Dat2kman.... Any body know a good machine shop as I have never done this job before...

Hi All, I have never posted any thing to this forum before however have had many hours of great reading. Thanks to all for this. I have owned my 260 for 26 years now and in the early days it was my daily drive. During its life it has been stored for extended periods while I had children etc. 5 years ago it was turned into a dedicated track car which generally gets a day or so each year at Philip island or Sandown to live the dream. I was getting it ready for a track day or two this year and whilst changing the oil discovered the dreaded milky colour and a river of silver. I took off the rocker cover and discovered the cam had been damaged and I have noticed that what I believe is water had entered the cylinder closest the fire wall of the engine bay. I have taken photos of the spark plugs and one of the cam for those to comment. I know on my last track day 2 years ago the car over heated, I have since changed the suspect stock radiator for a race one and am in the middle of installing an oil cooler. Previously I had installed a Wade cam the number stamped is 487 stamped on the end I would like to know if any body knows the specs of this cam as I just found out Wade cams has closed it's doors for good in February this year. I need to purchase another cam and would like to go bigger and not less than the damaged cam I have now. While I take the head off to change the head gasket I thought I would have it shaved a little to gain some compression. My questions are as the bottom end is stock what is the highest compression I should look to obtain and where should I go take my N42 head to be cleaned and shaved. I live in Mentone, Melbourne. The wade cam in it now pulled really well up to 6500 however I did not push it any further as I know it is an old engine and I did not want to break anything. I have Triple dellortos extractors and 2.5 inch exhaust straight through. I am in now way a mechanic, however probably just like most guys on the forum love car stuff and engines and want to tackle this myself and perhaps learn a couple of things along the way. Any help would be appreciated. Keep well, Gengis