Hi all,

Firstly I did a search under clearancing cam, clearance cam, camshaft clearance, camshaft gap, camshaft clearancing, clearancing camshaft and other things similar. All with no find on this site and yeas from the beginning - WTF. Surely it has been mentioned, I just can't find it

Anyway, what methods do you use to clearance the camshaft. Milling, grinder, lathe, die grinder, file (take a while), flapper wheel or what.

I would like to just do it at home for free, but also don't want any issues with weakening the camshaft. I personally don't like the idea of reducing the whole circumference on a lathe, I would just like to do the flat spots x 8.

Thanks, Kev

Plenty info out there.......google is your friend !

http://vwpwr.com/inbetween-races-the-turn-around/ 
http://www.thesamba.com/vw/forum/viewtopic.php?t=323796 
http://www.shoptalkforums.com/viewtopic.php?t=42457 

Thanks Craig,

I think I had already read those 3 links, but was just after feedback of what people here are doing. I have a die grinder but am a little reluctant to use that, so I may buy a narrower wheel for my bench grinder and try that. Just need to be careful that I don't get to much heat into it.

Kev

Ive never done one, so good luck

I've done some.....

I use a die grinder then flap wheel.

Like you said Kev, with big strokes the clearancing is best done in the areas that are necessary, the machined method becomes too weak for my liking.

How did you go with the cam gears?

Quote:

Originally posted by Craig Torrens Ive never done one, so good luck

Well, I got into it today and am happy with the outcome. Due to the shape of my rods, I made the clearaning curved rather than flat like others I have seen on the net.

Was trial and error, checking for clearance, pull it out and take a little more off it, back in and check, pull out and take more off again until I was happy with all.

Hopefully I have done it right. Thanks again for your input.

Kev

What clearance spec are you shooting for Kev? For that matter, what stroke and type of crank, and rpm do you expect, it's all relevant to this job

Hi Mat,

that photo my be a little deceiving. Trying to hold the conrod, the camera/phone and push the button all at once I may have altered the angle of rod making the gap look huge. I was aiming for 1mm or 40 thou, Scat crank and rods and I hope to rev it to about 6.5 - 7k.

Have a good long weekend (all), Kev

Thanks Kev, I was actually thinking it was looking tight. With type1/Chev journal crank (my guess) I'd recommend every bit of that and closer to 0.060 radial clearance for me to be happy. Enjoy Easter

Kev, hows your crank cheek and lifter to lobe clearance and rod cap to cam bearing shoulder clearance?

I also like to slight arris the cam lobe edges just to get rid of the jag.

Hi big fish,

have already taken the edges of the cam lobes and will make a few more checks today with what you mentioned thanks.

This is a photo I already had taken showing lobe to lifter clearance, I haven't measured the gap but will also do that today. What's your thoughts on gap size here.

Cheers, Kev

EDIT: Just measured and there is only .08mm or 30 thou gap, is this enough ??

*[edited]* oops
0.040" for lifter clearance, it's easy to get by radiusing the id of the lifter bore

Thanks Mat, looks like more mods required to the engine case. Glad I am double checking all this stuff before I bolt it together

Kev



EDIT: Mat, just been looking at the net and found this. Not disregarding your thoughts, just showing another's view -

Don't machine your lifter bores. Get the thin base lifters.

Machining the lifter bores can cause low oil pressure if the machinist goes a bit too deep.

I have a very expensive aluminum "race case" with machined bores that has always had low pressure when hot. I have to run a 30mm Melling pump in it to compensate.Oil pressure escapes from around the lifter when the bore boss is shortened.

Click here for the LINK to this info.

I like min 0.040" max 0.070" but have run as little as 0.025" on a mild cam 1776

There are a couple of ways to skin a cat as long as you're within spec, it's the first time I hear of low oil pressure due to lifter bore to shoulder clearance most likely caused by incorrect lifter body to bore clearance, lifters do vary in thickness if ever so slightly which will affect oil pressure.

Will check out the link in question.

I agree with Ben, that the oil pressure issues are excessive lifter bore clearances where the lifter is often under factory spec. This in a mild case can be rectified by ceramic coating the lifter, and a bad case, resleeving the lifter bores.
To get the cam full lift clearance, only a small radius is required for cams I've used and so this becomes negligible regarding weakening the lifter bore or reducing oil pressure. Having said that, I have to appologise as I rethought/checked my original spec for the full lift clearance required, 0.040" (1mm) is all that is required hence the small amount of radius required to achieve this. I have ammended my original post to reflect this.

c'mon Matty you were just testing us amateurs to see if anyones paying attention.

Quote:

Originally posted by fish26 c'mon Matty you were just testing us amateurs to see if anyones paying attention.

Yeah testing you guys....all part of the fun.

Matt, that engine of yours is a testament of your workmanship, smooth as silk, revs nice, drives hard and streetable.

Kev, whats the rest of the combo on this beast? or is there a build thread? How's your cam thrust and are there any tight spots on cam/crank gear?