Dif btw towers rockers & chain housing years

[relayswitcher]

I'd like to know what are the cam tower years in progression... "the same from this year to that, but can't be used on this engine or that one" sort of question I'm asking here.
Same answer for rocker arms, and chain housings, Please.
Thanks. R.

[Flat6pac]

The early aluminum through 67 can be used but there is 6 nuts on the exhaust valve cover side was strengthened to 11 nuts.
68 to 77 were generally the same. Early cam oiler tubes had 2 oils quirters for each cyl instead of 3 as the 70 on had.
76/77 3.0 carrera and turbos had 4 bearing cams as did 78 to 89 911/930s.
The 4 bearings are larger than the earlier 2.7 to differenciate the housings..but the increase in bearing size also allowed for larger, higher lift lobes.

chain boxes were early aluminum, less bolts and nuts
68 on were magnusium until the 3.0 Carrera and later cars were aluminum again

Most like pieces are interchangable.

Bruce

[Flat6pac]

Early rocker arms were forged through 67..jumping time was hard on the bottom end
cast Iron replaced forged steel
early cast iron didnt have brass bushings but soon got them
Bruce

[relayswitcher]

Originally Posted by Flat6pac

The early aluminum through 67 can be used but there is 6 nuts on the exhaust valve cover side was strengthened to 11 nuts.
68 to 77 were generally the same. Early cam oiler tubes had 2 oils quirters for each cyl instead of 3 as the 70 on had.
76/77 3.0 carrera and turbos had 4 bearing cams as did 78 to 89 911/930s.
The 4 bearings are larger than the earlier 2.7 to differenciate the housings..but the increase in bearing size also allowed for larger, higher lift lobes.

chain boxes were early aluminum, less bolts and nuts
68 on were magnusium until the 3.0 Carrera and later cars were aluminum again

Most like pieces are interchangable.

Bruce

Bruce, thanks for the information. Just to clarify to myself... Appreciate your responses, thanks for your help.
So this is what I'm understanding....
A. Towers are 6 bolt exhaust/ alum1965 thru & including 1967.
B. Towers are the same 11 bolt exhaust/ magn. 1968- 77. ( 2.oL , 2.2L, & 2.7L were exchangable towers, but do the '77 2.7S cams fit on a '70 911T etc. Q??: Are the lobe openings in the cam towers the same diameters so all the cams are interchangable? Aren't they different depending on carbs or fuel injection or even still, mech. Injection??

Just so you know where I'm coming from on all this is.....Hope you can follow my writing okay.

I bought a complete '77 2.7L engine partially disassembled. from someone for 300. and the case turned out to be bad, do I bought a 2.4L case from a local shop and had Ollie's Automotive Machining in Santa Ana bore it out for 2.7 P&L specs. I have an in-the-box set of Mahles ready to go. It so cool how they have the rings installed and oiled already.
I know very well about the 2.7L engine stud pulling problems from the factory because of the hot reactors..... so had them place the "coarse thread" stud inserts and resurfaced the barrel seats, so I'll use the 40mm copper gaskets between the new barrels and case they gave me.
I also had these 2.7L heads completely rebuilt including new guides and springs. I then bought a set of S cams on Ebay to use on this build. I'm using CIS for fuel delivery. I needed some towers & rockers so I bought 2 banks of 1973 Heads with rockers, cams, and towers still attached, again from the local shop ( Presicion Motion in Riverside, CA...good folks.) The heads have MF injectors still on them ( so will sell off). I can't tell if they are S, T, or E heads...can you tell from a photo? Anyway, the 2.7 crank mic'd fine so micro polished and its all built with new rod bearings and ready to go.
So here's the rub.... Can I use the '72-73 2.4L rockers for my 2.7L build? Can I use the cam towers with no problem, too. And are the '72-'73 2.4L cams the same as the S cams I bought on Ebay. How can I tell what cams go to what config. .... like CIS, or Webers, or MFI ?

2.4L Heads: 911.104.302.0R Valves: 40/46mm Ports: 30/35mm
2.4L Camshafts 911.105.142.0R & 141.0R 1629 is stamped on each shaft
S cams from Ebay: 911.105.143.0R & 144.0R

I'm also, thinking...... Building this 2.7 is going to cost more than I can sell if for.... I'm thinking in this economy it might be better off if I sold off everything ready for the 2.7L build one item at a time and make more cash in the long run. But..... on the other hand if someone wants a fresh 2.7L there has to be a buyer out there for sure.
Get back to me on this when you can.
Regards, R.
72-73 2.4L Heads MFI injectors....??? :

[relayswitcher]

Close up of one of the injectors on the 2.4 Heads
.....

[Flat6pac]

All the stuff is mix and match. The carriers work across the board as do the rockers.
The heads only match to 2.4 cis with small ports
2.7S use 2.7 S heads with the cis
S cams will be 143/144, early S wont work

Bruce