103.942 head onto a 103.983?
 

will a 2.6 liter head from a 90 260e fit on a 89 300te? Im seeing a different gasket part number.

Any ideas about this union?

less power, will not mate? better fuel economy. etc

mostly though will or would it work?

found at ehow
 

Comparing the 2.6 L and 3.0 L
The Mercedes Benz 2.6-liter M103 was almost mechanically identical to its larger 3.0-liter stablemate. The only difference between the two engines was an increase in bore from 82.9 mm in the 2.6-L to 88.5 mm in the 3.0-L variant, smaller intake valves and a slightly different air box. The 3.0-L M103 with a catalyst produces 177 horsepower at 5,700 RPM and 188 ft.-lbs. of torque at 4,400 RPM while the version without the catalyst generates 185 horsepower at 5,700 RPM and 191 ft.-lbs. of torque at 4,400 RPM.

3.0 L Swapability
Due to the mechanical similarities between the 2.6-L and 3.0-L variants of the M103 engine, swapping them out between models is moderately easy as it's as simple as a bolt-on process, without any extra fabrication. Those seeking to gain a performance upgrade by swapping in the 3.0-L engine can find this larger power plant in the 1986 through 1993 W124 300 E, the 1988 through 1989 W124 300 CE, the 1988 through 1993 W124 300 TE, the 1989 through 1991 W126 300 SE, the 1989 through 1991 W126 300 SEL and the 1985 through 1989 R107 300 SL. It was also offered in the W463 G-Class SUV, but this model never made it to the United States other than through the gray-market.



Read more: 260E M103 Engine Specs | eHow.com http://www.ehow.com/list_7164985_260e-m103-engine-specs.html#ixzz1HCh5WQ8r

Physically they fit, yes. But I thought you couldn't use the later 3.0 head (90-92) with the different style combustion chamber, on an early block? So I assume the opposite would be true (late 2.6 head onto early 3.0) Or does it work, but compression will be affected?

Another thing you definitely don't want is the non-hardened camshaft/rockers that came on the 86-89 cars, unless they have already been replaced.

What's wrong with your current head? Unless it's badly warped which is very rare, everything can be rebuilt to factory spec and skimmed for $200-300 by any competent machine shop.

short story 5 cent tour
 

I am a everyday driver so downtime is big deal. In my little head I got a brite idea, have a rebuilt head to replace the existing head henceforth no big downtime... 1st picked out a head at j-yard, turned out to be warped .013 and not enough material left to take additional .020 off to correct.
Went back to j-yar and eyed a 90 300sel, sweet car, head bolts pushing 200ft-lbs of torque and cant do it, give up on that one.
Look at a sweet little 90 260e head and pull it, not its here in garage awaiting word on the works to have it machined.
If it wont go or not worth it I will face the music and deal with downtime to get the original resurfaced.

THe 2.6 has a significantly smaller combustion chamber and although such monster might run it would be plagued with problems that couldn't be easily engineered out.