+ Reply to Thread
Results 1 to 20 of 41

Hybrid View

  1. #1
    dwa1971
    Guest
    Location
    , ,
    Member No: dwa1971's Avatar


    Yes | No

    which model/yr of 80's M30 engines had big valves

    I know that certain year m30 engines in the 80's 3.5s had small valves and others had larger ones. I would appreciate it if someone could let me know which is which. Thank you

    dwa1971

  2. #2
    Registered Member
    Location
    , ,
    Member No: 14640 bimmerphile73 is an unknown quantity at this point bimmerphile73's Avatar
    Join Date
    Oct 2001
    Posts
    2,221
    Rep Power
    0


    Yes | No

    Big Valve Engines (M30B35)...

    1987-1992 E32 7 Series
    1988-1993 E34 5 Series
    1988, 1989 E24 6 Series

    Those are all U.S. model years, build dates can be different. For example E32 model year 1987 production began in August, 1986. Model year 1988 6 Series production began in June, 1987. In addition to bigger valves, these engines have higher compression ratio, resulting in 208 hp in the U.S models. Most, except for the very early 7 Series and the 6 Series engines, require an adapter for the right engine mount.

    These engines can be identified by the toothed harmonic balancer and the intake manifold being braced underneath instead of being braced to the valve cover.

  3. #3
    dwa1971
    Guest
    Location
    , ,
    Member No: dwa1971's Avatar


    Yes | No

    Re: Big Valve Engines (M30B35)...

    Is it worth it to go to one of these vs. the smaller valve 3.5s for ease of install to the e9? thanks

  4. #4
    Registered Member
    Location
    , ,
    Member No: 14640 bimmerphile73 is an unknown quantity at this point bimmerphile73's Avatar
    Join Date
    Oct 2001
    Posts
    2,221
    Rep Power
    0


    Yes | No

    Absolutely...

    You can get an adapter from Carl Nelson's shop, La Jolla Independent, 800 466-8184. It's a custom built item, so it'll take a bit of lead time.

    If you're going with the Motronic, the engine is better since you won't need the motronic bell housing, since the sensors are on the front of the engine. If you're going with carbs, the engine is better because it breathes better than the M30B34 engine.

  5. #5
    dwa1971
    Guest
    Location
    , ,
    Member No: dwa1971's Avatar


    Yes | No

    Re: Absolutely...

    Thanks, yes I know Carl well and he knows my credit card well. I plan to go the carb route as I hate electronics and such and prefer old school. I have been planning this for some time and will most likely do it this winter after I find the right engine.

  6. #6
    dwa1971
    Guest
    Location
    , ,
    Member No: dwa1971's Avatar


    Yes | No

    Re: Absolutely...part 2

    What sort of 5 sp do you suggest as I have heard everything from an early 533 tranny to just leaving the 4 spd which I hate. I appreciate your thoughts.

    dwa1971

  7. #7
    Registered Member
    Location
    , ,
    Member No: 14640 bimmerphile73 is an unknown quantity at this point bimmerphile73's Avatar
    Join Date
    Oct 2001
    Posts
    2,221
    Rep Power
    0


    Yes | No

    Getrag 265/6 Overdrive...

    First, the 265/5 is the "dogleg" 5 speed which has a 1:1 final ratio. You don't want that one unless you're planning to do the Pike's Peak Hill Climb. And according to Carl, it's a POS. The 265/6 was in various early '80s 5, 6, and 7 Series, as well as the 1985 5, 6 and few 7 series and also the E30 M3. The 1985 transmissions require the addition of the speedo gears, since those cars had electronic speedometers.

    Don't bother with the Getrag 260 series, the early ones (pre 1985) suffered from poor layshaft lubrication, the later (post 1985) ones aren't much better. The reason BMW went back to the 265 in 1985 was that the 260 wasn't hacking the program. The 260s have an integrated bellhousing and the 265s have separate bellhousings.

    The 262 4 speed is a great transmission, but if you want a 5 speed, the engine swap is the obvious time to do it. Carl can fix you up. His children will appreciate the college educations we are all providing for them.

  8. #8
    Registered Member
    Location
    , ,
    Member No: 130402 PORCHE505 is an unknown quantity at this point PORCHE505's Avatar
    Join Date
    Aug 2005
    Posts
    147
    Rep Power
    0


    Yes | No

    Dont get excited about the valves

    The only change in the m30 valves is for the b35, as mentioned. The thing is that it only grew 1mm. Every other m30 head has 46/38 valves. Nothing to get excited about there. Pistons can be used to bring up compression, so all the b35 really has is displacement. Its not as special as everyone thinks it it.

  9. #9
    Registered Member
    Location
    , ,
    Member No: 14640 bimmerphile73 is an unknown quantity at this point bimmerphile73's Avatar
    Join Date
    Oct 2001
    Posts
    2,221
    Rep Power
    0


    Yes | No

    Right...

    And the difference between 182 hp and 208 hp is inconsequential. That could have been easily accomplished with just an increase in displacement and compression ratio? I'm guessing not, otherwise BMW would not have invested all that time and money changing the valves (and the head, and the intake manifold) in the first place.

    But I'm no fluid dynamics engineer, maybe someone has a flow analysis that can show why they wasted all that effort.

  10. #10
    Registered Member
    Location
    , ,
    Member No: 130402 PORCHE505 is an unknown quantity at this point PORCHE505's Avatar
    Join Date
    Aug 2005
    Posts
    147
    Rep Power
    0


    Yes | No

    Can you say motronic 1.1?

    That, the 264 degree cam, the higher compression pistons and motronic 1.1 would be more than enough to do it. Or do you honestly think it was a 1mm larger intake valve instead of more modern fuel injection, a hotter cam and higher compression?

  11. #11
    Registered Member
    Location
    , ,
    Member No: 14640 bimmerphile73 is an unknown quantity at this point bimmerphile73's Avatar
    Join Date
    Oct 2001
    Posts
    2,221
    Rep Power
    0


    Yes | No

    LOL! I need to open a palm reading place...

    I knew you were going to bring that up.

    No, if you will read my post carefully, I asked if you thought that just an increase in compression ratio and displacement would be sufficient to raise the power that much. By implication, they do have an effect. Motronic 1.1 has some nice driveablity improvements, such as controlling cold starting from the ECU rather than using a cold start injector, but that doesn't increase power. Try putting Motronic 1.1 on a B34 engine. Will it produce any more power? No, 1.1 doesn't cause the extra power and torque, its mapping allows the B35 engine to take advantage of the increased compression ratio and cam duration. Motronic 1.1 has greater spark advance, which is needed to take advantage of the higher compression ratio, which in turn requires premium fuel. But you can do those things using carbs and a distributor, as well. 1.1 just does it in a very elegant manner. As I mentioned in the very first post, the bigger valves allow the engine to breathe better. The bigger valves let even more air in during that longer duration intake cycle. Maybe 1 mm doesn't seem like much but evidently it's enough. Again, tell me why BMW would bother if all the other changes were enough.


  12. #12
    Registered Member
    Location
    Rio Rancho, NM, United States
    Member No: 124000 528ita is an unknown quantity at this point 528ita's Avatar
    Join Date
    Apr 2005
    Posts
    2,833
    Rep Power
    0


    Yes | No

    The math says:

    Thats only another 13.4 cubic millimeters. The motronic 1.1 and 264 cam compliment each other for the extra power. I dont think another 13.4 cubic millimeters of valve opening is going to blow anyone away. Its the cam and matching EFI.

  13. #13
    Registered Member
    Location
    Perris, CA, United States
    Member No: 129993 Earlyshark is an unknown quantity at this point Earlyshark's Avatar
    Join Date
    Aug 2005
    Posts
    452
    Rep Power
    0


    Yes | No

    Carl had done a friends 3.0 CS a few years ago

    It's not that big a deal, when looking at both heads side by side, the B35 head is a more "open chamber" design, which would result in lower compression on an earlier engine. The intake ports are wider and the stock intake manifold barely seals on the sides. It produces a "step" going from the intake to the head, not a smooth transition. I am going to install an M90 (same bore and stroke as the M88/S38) in my '74 Euro 3.0CS. It is the engine used in the '79-'81 M535 and Euro '79-'81 635 and 735 - 218 HP. In california a '74 or earlier CS will not need to wory about smog issues, so I may upgrade with a Schneider cam, headers and B35 head with L-Jet manifold with motronic 1.1. A friend installed a new B35 that had been in his 633 into a '89 635 and he said the newer electronics "woke it up". The motronic bellhousings for the 265 trannys are very hard to come by, Carl just got one a week or 2 ago.

+ Reply to Thread


Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

     

Bookmarks

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
1e2 Forum