Mystery 24v cam, tray, and lifter questions?

[YeOldeBuggy]

Starting info: I have an m52 swapped e30, with what were supposed to be s50 cams, trays, and lifters (I bought and installed them myself off of bimmer forums a few months back)
Gents, I've been ramming my head into a brick wall trying to figure THIS shit out. I recently purchased new lifters to replace the noisy supposed s50 lifters. However, the new lifters (confirmed to be correct by Blunt himself) are about 1/16th of an inch smaller in diameter than the old lifters (and also the bore in the trays, just an fyi) and also about 1/16th of an inch shorter. But the cams fit in both the old m52 tray and the new "s50" tray with no issues. And the car runs fine with the new cams, trays, and lifters.... what fucking trays do I have that would have lifters of that size in them? I've been hunting online, and Blunt sent me the link to realoem showing that the s50/m50/s52/m52 all use the same lifter part number...... Thanks ahead.

/rambling question

Thad.

[328ijunkie]

Idk where you got the lifter part number but early and late models use different lifters/trays. The late model lifters/trays are smaller diameter than the early model ones.

[YeOldeBuggy]

Interesting information, do you have an early model part number? s50 is early I assume, and the seller seemed legit. That's why I was confused. But realoem does show that all of the engines use the same lifter, wtf? It seems that the m50 is the only engine that has a different part number for it's lifter.

[YeOldeBuggy]

I found on vac motorsports that the early m50 head has 35 mm lifters and all of the rest are 33 mm... hmmmmm, sounds like I got screwed on my "s50" cams...

Thad.

[Wanganstyle]

I found on vac motorsports that the early m50 head has 35 mm lifters and all of the rest are 33 mm... hmmmmm, sounds like I got screwed on my "s50" cams...

Thad.

NON vanos M50 has weird larger size lifters.

usa s50 and s52 have same lifter size as all M50/m52 vanos

are both your cam trays using same size lifters?

if your intake cam was from a M50 Non-Vanos, it would not work with vanos. they are not compatible; does your engine have vanos?

If you post some photos of both camshafts I'm sure some one on R3v can ID them.

its possible that your cam trays are M50 non vanos paired w s50 cams (or s52 with modification)

[YeOldeBuggy]

Well, how could I have vanos cams with nonvanos lifters and trays? And why would they've been paired together?

Thad.

[graphikg]

I thought you could not use s52 cams with M50/S50 trays. I am not sure about the tray bore size though. If you have S50 cams, make sure your trays are for an S50 or M50 also, and make sure the lifters match for the trays. Pics may help you though. Cams are an easy thing to sell and make money off of them being bogus.

[YeOldeBuggy]

The only thing truly in question currently is the cams, the trays and lifters must be early m50, due to the fact that they are 35 mm lifters, I just found out how to mic the cams, and shall do so, they seem to have slightly more lift than my m52 cams, which makes me wonder if they could be reground m50 cams, or what exactly they are, I shall see soon. Fuck, what a mess.

Thad.

[graphikg]

Get the part numbers off the cams and make sure... and just buy some used M50/s50 vanos lifters and trays, and you should be good.

[YeOldeBuggy]

From what I've read, it isn't that simple, the numbers on the cams aren't necessarily part numbers, I've read that some think they could be casting numbers, or something to that extent. I've read that the best way to tell m50 cams from s50 cams is by mic'ing them and getting the lift of said cam.and, since they are m50 trays and lifters, if my cams are s50 cams, they should work wonderfully well together.

Thad.

[Wanganstyle]

take a photo of the casting numbers, and we will all dig through photos, I have photos of S52 cams and S50 cams side by side....somewhere that I took myself

it is possible that the early cam carriers could be modified to fit Vanos cams, as these things are pretty modular- obd1 vanos cam carriers can be modified to fit obd2 cams with counterweights. I dont see why the cam carrier lifter size should matter when putting in cams, S50 cams will fit all cam carriers with no modification- s52 ones need OBD cam trays because of the additional counter weights on the cam itself.

People have documented modifying early cam carriers for obd2 s52 cams; I don't see why a non-vanos one shouldn't be able to be made to work- its just a bearing surface; the carrier tray bore determine the HLA lifter size.

I installed S52 cams+cam carriers +Vanos on a M50 1991/2 non vanos head on purpose, then stuffed it into my 97 M3; ran with Stock OBD2 electronics; S52 everything.

Gain was double valve springs and thicker (more durable, not higher performance) valve stems.

[EduardoGomez]

the new lifters (confirmed to be correct by Blunt himself) are about 1/16th of an inch smaller in diameter than the old lifters (and also the bore in the trays, just an fyi) and also about 1/16th of an inch shorter.

New lifters that you got are M52/S52 lifter. Old lifters that you got are M50tu/S50 lifters. And it looks like you got the M50tu/S50 trays as well.

But the cams fit in both the old m52 tray and the new "s50" tray with no issues.

Correct. 1995 S50 M3 camshafts will fit the older M50 and newer M52 trays.

So this means the guy who sold you the engine told you the truth. You got S50 cams and trays and lifters in there.

[YeOldeBuggy]

I did not buy the engine, I bought the cams, trays, and lifters from the engine. And, unfortunately, you are incorrect. I measured the lift on the cams, and came up with 9 mm. Same as my old m52 cams. It is very hard to distinguish m50 and s50 cams. And the only thing that tipped me was the difference between the lifters when I went to replace some of my noisy ones. Now I think you are incorrect in the assumption that both m50 and s50s use 35 mm lifters. All of my internet research points towards early m50s ONLY, using 35 mm lifters.

Thad.

[328ijunkie]

S50s also use 35mm lifters.

and for cam differences you should be able to visually tell which is which:

http://forums.bimmerforums.com/forum/showthread.php?t=1559524

[328ijunkie]

Get the part numbers off the cams and make sure... and just buy some used M50/s50 vanos lifters and trays, and you should be good.

Check the thread i just posted. There isnt part numbers on them.