are aftermarket cams just as fragile?

[haaken675]

Hey everyone. Trying to further plan my build and am a bit curious on this one. I know that the stock m5x/s5x cams are hollow and can easily snap if you are not removing them or installing them just right. That is literally the only part of my build I am planning that concerns me since I have never swapped cams on an overhead cam motor before. I would hate so spend big money on aftermarket cams just to snap them on install...

Does anyone have experience with schrick, sunbelt, or cat cams? are they solid instead of hollow? Are they any more robust then stock, or just as fragile? I searched online but couldn't come up with the answer I was looking for.

Thanks

[nando]

I don't think stock cams are hollow (BMW didn't do that until the N52) - they break because cams are made of a really hard/brittle steel that will crack if you stress it too much.

If you are careful when removing the caps (go slowly and work evenly to keep the pressure the same along the camshaft) it shouldn't be an issue. You could also use a cam bearing tool which supports to the cam while you loosen the caps.

[haaken675]

Hmm, I thought they were hollow. Either way, at least I know they are brittle!

I will look into the cam bearing tool. I haven't heard of anyone using that yet. I know there is a good article on pelican parts I have read a few times about finding a "sweet spot" were there is as little pressure from the valve springs as possible. It's also possible I blow out of proportion how fragile the cams are since I always worry about stuff like that.

[nyChris]

It is insanely nerve racking, but go slow and even and you will be ok. I've done it personally 4 times now. It takes me around 20 minutes to loosen them all because I go 1/4 turn at a time.. Its tedious.

I don't think stock cams are hollow (BMW didn't do that until the N52) - they break because cams are made of a really hard/brittle steel that will crack if you stress it too much.

If you are careful when removing the caps (go slowly and work evenly to keep the pressure the same along the camshaft) it shouldn't be an issue. You could also use a cam bearing tool which supports to the cam while you loosen the caps.

The s52 cams at least are 100% hollow.

Good luck finding the tool... I tried. Anyone who has it will not rent it, and the dealer mechanics obviously wouldn't let me use theirs.. I'm suspicious they didn't even have one. Its like a $4K tool I was told. I also heard a story that the tool is made by one man in a small shop in Germany, and that there is a wait list even if you wanted to buy your own.. don't quote me on this myth.

[haaken675]

It is insanely nerve racking, but go slow and even and you will be ok. I've done it personally 4 times now. It takes me around 20 minutes to loosen them all because I go 1/4 turn at a time.. Its tedious.



The s52 cams at least are 100% hollow.

Good luck finding the tool... I tried. Anyone who has it will not rent it, and the dealer mechanics obviously wouldn't let me use theirs.. I'm suspicious they didn't even have one. Its like a $4K tool I was told. I also heard a story that the tool is made by one man in a small shop in Germany, and that there is a wait list even if you wanted to buy your own.. don't quote me on this myth.

That is the exact same story about the tool I have heard. I am willing to bet most dealers do not have that tool at all...

When you loosened each nut/bolt on the cams, did you first rotate them at all to try and find a point with less tension?

[nrubenstein]

The tool is completely unnecessary. It's easy to do, just don't stress about it.

[328ijunkie]

Stock cams are hollow. (N52 cams are hydroformed hollow) If youre slow and keep load even youll be fine.

[haaken675]

Awesome. Thanks for the feedback everyone!

[nrubenstein]

Also, if you don't have one, buy a speeder bar. For this kind of work, where power tools are a bad idea, it's wonderful.

[haaken675]

Also, if you don't have one, buy a speeder bar. For this kind of work, where power tools are a bad idea, it's wonderful.

I will look into that. I have never heard of a speeder bar, but I do love me some tools!

EDIT: just looked into a speeder bar. I didn't realize that is what those were called. You learn something new everyday...

[Northern]

That's the first time I've heard it called a "speeder bar" instead of "speed handle"
Probably just one of many tool names that vary on location/trade lol.

[ForcedFirebird]

Stock 24v cams are 100% hollow cast iron, and always have been AFAIK.

They do break, but as mentioned, if you go a thread on each cap back/forth you will be ok. Also note the rotation of the cam, there will be one spot that has the least resistance on nearly all the lobes.

[M3PO]

Just pay attention to which cylinders have pressure on them and be careful not to back those cylinders off too fast. This transfers the stress further away which is what causes them to bend and break.

[MR E30 325is]

Please follow this guide.

http://www.pelicanparts.com/BMW/techarticles/E36-Camshaft-Removal/E36-camshaft-removal.htm

This job is not difficult at all.

Slowly loosening all of the caps at once is a way to get the job done, but it is too slow and the drama is sustained for far too long.

Simply rotate the camshaft to a position where just one set of valves is open, i.e. one cap has load on it (you can ensure this is the case by spinning the lifters of the unloaded valves with your pinky finger. If it spins then no load is being applied to the camshaft). Hold the camshaft in place, rotation wise, with a crescent wrench. Remove all 6 caps with no load. Finally, loosen each of the two nuts on the last cap 1/4 turn at a time.

Voila. This works for both intake and exhaust. I think I used cylinder 2 as my pressure point.

Just did this. No sweat and no issues. Much easier than freaking out for 20 minutes as you try to remember each and every nut that you turned a boatload of times.

[haaken675]

Please follow this guide.

http://www.pelicanparts.com/BMW/techarticles/E36-Camshaft-Removal/E36-camshaft-removal.htm

This job is not difficult at all.

Slowly loosening all of the caps at once is a way to get the job done, but it is too slow and the drama is sustained for far too long.

Simply rotate the camshaft to a position where just one set of valves is open, i.e. one cap has load on it (you can ensure this is the case by spinning the lifters of the unloaded valves with your pinky finger. If it spins then no load is being applied to the camshaft). Hold the camshaft in place, rotation wise, with a crescent wrench. Remove all 6 caps with no load. Finally, loosen each of the two nuts on the last cap 1/4 turn at a time.

Voila. This works for both intake and exhaust. I think I used cylinder 2 as my pressure point.

Just did this. No sweat and no issues. Much easier than freaking out for 20 minutes as you try to remember each and every nut that you turned a boatload of times.

That is exactly the article I was referring to I think in my original post. I will have the cylinder head off for this job, so hopefully it won't be too big of a deal. Im sure I can always find a way to hold the valve open if I really get antsy as well...