M60B40 Heads on M62B44 Block

[nrubenstein]

Have you considered using a taller head gasket to slightly reduce the compression ratio?

[Jonsku]

I am still eagerly awaiting some real world data and results. If this conversion DOES work, I would expect over 300 bhp.

Tune M60B40 ECU properly and you're at 300-305hp ... ;) With the 4.4 you should be around 330hp figure.

I remember someone stating that both the b40 and b44 have flat top pistons that reach the top of the block. Assuming that the head gaskets are the same thickness, it should be pretty close to 11:1 comp on the frankenstein.

B44 with VANOS have valve-pockets in the pistons and slightly raised center parts. non-vanos M62's and all M60's seem to have flat pistons.

[Jean]

Have you considered using a taller head gasket to slightly reduce the compression ratio?

I remember when getting gaskets for the m62tu, there were two options, I don't know if the same exists for the M62b44 since thats the gaskets we have to use to match the bottom end, and also custom make the front piece to match the timing covers.

[CoreyZ]

Have you considered using a taller head gasket to slightly reduce the compression ratio?

Now why would you want to go and do that? :twisted:

[The Dark Side of Will]

I remember when getting gaskets for the m62tu, there were two options, I don't know if the same exists for the M62b44 since thats the gaskets we have to use to match the bottom end, and also custom make the front piece to match the timing covers.

So on the M60, the head gaskets include the seal between the upper and lower timing covers.
According to RealOEM, on the M62, the seal between the upper and lower covers is included with the "profile gasket" that seals the upper timing covers to the cylinder head.

So does using the M60 upper cover and heads with the M62 lower cover result in a gap that's too big to fill with the M62 gasket?

[bmwmech1]

So on the M60, the head gaskets include the seal between the upper and lower timing covers.
According to RealOEM, on the M62, the seal between the upper and lower covers is included with the "profile gasket" that seals the upper timing covers to the cylinder head.

So does using the M60 upper cover and heads with the M62 lower cover result in a gap that's too big to fill with the M62 gasket?

Will, the timing covers of the 2 motors are more different than just the sealing system. The big reason to use the M60 lower cover is the crank position sensor mount, which moves it to the front. There is no reason, or way to use the M62 lower cover with the M60 upper covers because of the gasket differences. The M62 head gaskets must be used because of the bore size, but there is no provision for the upper/lower cam cover gaskets. On the M62, the cam cover gasket is a rubber seal that fits into the cam cover, hence the head gasket not having any provision for it. When doing this hybrid setup, I made my own upper to lower cam cover gaskets. The gaskets that seal the cam covers to the block, both upper and lower, are the M60 gaskets. It's pretty much that simple. M62 block, M62 head gaskets, M60 heads, M60 timing covers, M60 block to covers gaskets and homemade upper to lower gaskets...

Garey

[Jean]

I am picking up m62 heads this week from machine shop, then I can measure the head combustion chamber volume. I am guessing I'll try doing it with water and see how that goes.

[bmwmech1]

... I am guessing I'll try doing it with water and see how that goes.

Use alcohol... less of a meniscus, so your measurements will be easier to read in the burette and more accurate...

Garey

[Jean]

Use alcohol... less of a meniscus, so your measurements will be easier to read in the burette and more accurate...

Garey

Good point! Another good use for Vodka?! lol

[iamsam]

ok any more progress on this?

Has anyone else done this? I have been hearing hints that it has been done.

Also, it seems people in this subforum have experience with this, but can you take assembled head to get cleaned, or do you have to strip them down (remove valves etc)? Same story w/ the block with respect to the rotating assembly?

[The Dark Side of Will]

Will, the timing covers of the 2 motors are more different than just the sealing system. The big reason to use the M60 lower cover is the crank position sensor mount, which moves it to the front. There is no reason, or way to use the M62 lower cover with the M60 upper covers because of the gasket differences. The M62 head gaskets must be used because of the bore size, but there is no provision for the upper/lower cam cover gaskets. On the M62, the cam cover gasket is a rubber seal that fits into the cam cover, hence the head gasket not having any provision for it. When doing this hybrid setup, I made my own upper to lower cam cover gaskets. The gaskets that seal the cam covers to the block, both upper and lower, are the M60 gaskets. It's pretty much that simple. M62 block, M62 head gaskets, M60 heads, M60 timing covers, M60 block to covers gaskets and homemade upper to lower gaskets...

Garey

Interesting. Thanks for the info. I haven't been receiving reply notifications for this thread, or I'd have gotten back to you sooner.

So if I were to build one of these, I'd almost certainly go with Cometic head gaskets to optimize the quench clearance. I'm guessing they could cut M60 style gaskets with the M62 bore size. I've ordered directly from them twice and requested a non-standard bore both times. It was a non-issue... they didn't even charge me extra.

[The Dark Side of Will]

Have you considered using a taller head gasket to slightly reduce the compression ratio?

11:1 on pump gas should be fine as long as the head gasket is *THIN* enough to optimize the quench clearance.

My Northstar is running 11.5 and doing fine with 93 octane.

[iamsam]

a little off topic, but not too far off, how realistic would it be to slap M60B40 heads, intake mani, t-chain, etc on an M62TUB44 in an '01 540i M-sport?

That may be a very real need, since the t-chain skipped some teeth when a guide rail exploded.

Ideally, this would eliminate VANOS, but keep everything OBD2.

[Jean]

Ouch! I wouldn't even want to start with that :/

[iamsam]

Ouch! I wouldn't even want to start with that :/

why? Let's hear some backup reasoning...