newb questions about S52 swap

[Larry e30]

I have an M50TU and plan on swapping that engine out within the next month with an S52. Now with the S52, I only have the block and some other parts, so I'll be using the head from the M50. So do I have to buy new head bolts? I heard not to reuse them, and also should the number one cylinder on the S52 be at top dead center when I put the new head on?

-Larry

[Tarn]

As far as the head bolts, yes you must replace them because they get stretched on install. Not to sure on the head matching the s52 so im going to leave that alone.

[madjurgen]

As far as the head bolts, yes you must replace them because they get stretched on install.

I dont think so. Head bolts arent torqued above their yield point afaik.

[matt]

I dont think so. Head bolts arent torqued above their yield point afaik.

Wrong. They certainly are.

[quillbro]

Where do you get new bolts? Is it a common thread pitch and size? Or is it a special OEM part number? Just asking cuz I'll be assembling a block and head soon

[matt]

Buy them from BMW or OEM, they are sold in a set. You need to install them properly also... this is critical.

[quillbro]

Found a link to em on Fleabay...

http://cgi.ebay.com/ebaymotors/Parts-Accessories_Car-Truck-Parts-Accessories__BMW-Set-14-of-Cylinder-Head-Bolts-S50-S52-M3_W0QQitemZ320225028950QQddnZPartsQ20Q26Q20AccessoriesQQadnZCarQ20Q26Q20TruckQ20PartsQ20Q26Q20AccessoriesQQddiZ2811QQadiZ2865QQcmdZViewItem?_trksid=p3756.m20.l1116

Install correctly? I imagine thats a Cris-Cross incremental torque pattern with a certain lb/ft torque spec? Care to tell?

[Drew325is]

Head studs are not something I would be going to ebay for. Also, buy a good workshop manual (e.g. Bentley) and follow the correct 3-stage torque-down procedure.

[quillbro]

Head studs are not something I would be going to ebay for. Also, buy a good workshop manual (e.g. Bentley) and follow the correct 3-stage torque-down procedure.

They're from Bavauto recycling and supposedly new... but yeah im a newb at these things anyway...whats a good source? Id rather not lay out 189dollars for the APR ones.

[Drew325is]

I'd just be going somewhere I'm 100% sure of (maybe that's Bavauto Rec - I have no experience with them, and am not trying to knock them)...but in this case I'd just suggest having some local accountablility and maybe get some technical advice as well.

[Van Westervelt]

Just pick them up at the Dealer. They are only like $40. Or call up BMAparts.com and make an order for them.

[broke30]

Head studs are not something I would be going to ebay for. Also, buy a good workshop manual (e.g. Bentley) and follow the correct 3-stage torque-down procedure.

Those are not head studs. And to the original poster, BMW oem head bolts as Matt said ARE torque to yield. Head STUDS on the other hand are not, in most cases you can reuse head studs. A new set from pelican is dirt cheap, I don't know why you would even think about reusing the old ones to save like $30......
Max

[Drew325is]

Those are not head studs. And to the original poster, BMW oem head bolts as Matt said ARE torque to yield. Head STUDS on the other hand are not, in most cases you can reuse head studs. A new set from pelican is dirt cheap, I don't know why you would even think about reusing the old ones to save like $30......
Max

Sorry, meant bolts...and I agree with not reusing them.

[Larry e30]

Alright cool, is there anything else that shouldn't be reused other than gaskets?

[gobuffs]

If you are asking these questions, do you have the know how and abilities to undertake such a project?


And on the reusing head bolts....this debate is ongoing on S14, there are reputable engine builders that say they can be reused, some say to get new. I have friends that have reused them with no ill effects.