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    This is probably a really dumb question but is there anyway to put an I cam and valve springs in a Super ETA without pulling the head off the engine? I'm really doubting it but it'd sure be nice.

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      Originally posted by 884door View Post
      This is probably a really dumb question but is there anyway to put an I cam and valve springs in a Super ETA without pulling the head off the engine? I'm really doubting it but it'd sure be nice.
      you are going to have to drill oil passage holes in the cam bearins and remove valve springs. If you can keep the cylinder pressuized you can swap valve spring one pressurized cylinder at a time. And you would have to make sure you get ALL the aluminum shavings out of the head from the drilling.
      Drilling the holes is easy, I did this to an eta head not too long ago.
      -Andy

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        You do not have to drill squat in a super eta head. It already has a 7 bearing cam since it is an i head, the only difference is the cam profile and the dual springs. However, you cannot (easily) replace the springs without pulling the head, which is fine since your head gasket is probably old and could stand to be replaced.
        -P

        Moosehead Engineering

        Comment


          Originally posted by mooseheadm5 View Post
          You do not have to drill squat in a super eta head. It already has a 7 bearing cam since it is an i head, the only difference is the cam profile and the dual springs. However, you cannot (easily) replace the springs without pulling the head, which is fine since your head gasket is probably old and could stand to be replaced.

          Yea I was presuming it'd be hard/impossible to keep the valves in place while replacing springs.

          I've had a complete I top end sitting around for months and now I'm really itchin to put it on. Just need to come up with some money for gaskets and an ecu first. Oh and I figure it's probably worthwhile to replace the timing belt while I have the motor all ripped apart anyway.

          Comment


            The hardest part would not be keeping the valves in place. The hardest part is pulling the rocker shafts, then finding a valve spring compressor that can actually do the valves from the top. The gasket set and head bolts are not that much, and a timing belt and tensioner are less than $50, so you'll have the money soon enough. PM me if you need an i computer. Good luck.
            -P

            Moosehead Engineering

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              Now that I have converted to i electronics and '89 engine harness, I'm wondering if it is possible to do the stomp test. I don't have a "check engine" light (1986 325) but it seems like you could wire up a bulb to act in its place. Any thoughts?
              sigpic

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                Find the wiring diagram and hook up a light bulb and you should be good to go. I think the signal comes from the small plug in the engine harness next to the ECU. It won't really tell you much, though.
                -P

                Moosehead Engineering

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                  Can you guys let me know what you think about this recipe?

                  M20B27 crank, block and rods
                  11:1 cr pistons (from early euro eta)
                  will the 731 head work with these pistons?

                  OR

                  M20B27 crank, block and rods
                  10.2:1 cr pistons (euro eta)
                  i head (I can use the i head because the 10.2:1 Mahle pistons have flat tops, right?)

                  Comment


                    Originally posted by structured View Post
                    M20B27 crank, block and rods
                    11:1 cr pistons (from early euro eta)
                    will the 731 head work with these pistons?
                    The 731 head is almost identical to the 200 casting, and should work keeping an 11:1 cr. Flows better (not quite as good as the 885 head), and can take advantage of the "i" intake. Only downside is the smaller valves.

                    Originally posted by structured View Post
                    M20B27 crank, block and rods
                    10.2:1 cr pistons (euro eta)
                    i head (I can use the i head because the 10.2:1 Mahle pistons have flat tops, right?)
                    While the combination should be sound, the 10.2:1 pistons are still dished, not so much as the standard eta pistons. When paired with the 885 "i" head, you should see something in the neighborhood of 9.5:1. The only drawback is that the pistons do not match the combustion chamber of the head, and may leave a few HP on the bench as a result.

                    Given a choice between the two, I'd choose the 10.2:1 pistons with the 731 head. That at least gives me some options when at the pump!

                    (Related to original post - Just finished an e to "i" swap on a 528e. Thanks to this thread (a few others like it), it went off with out a hitch! Well, maybe a few minor ones. But those get filed under lessons learned.)

                    Comment


                      Originally posted by rcfanatic View Post
                      Now that I have converted to i electronics and '89 engine harness, I'm wondering if it is possible to do the stomp test. I don't have a "check engine" light (1986 325) but it seems like you could wire up a bulb to act in its place. Any thoughts?
                      1986 Model year, or build date? I was pleasantly surprised to find the check light portions of the harness present in my 12/86 528e. It just required a little digging behind the instrument cluster to un-earth.

                      And it works fine. Stomp test and all. Mind you, all it really does is inform you that the ECU has detected a fault with a sensor. (Which can be helpful after you complete the ECU swap. Did you know the engine will run (poorly) with the temperature sensor wiring swapped? :oops: )

                      Comment


                        Originally posted by jmc1590 View Post
                        The 731 head is almost identical to the 200 casting, and should work keeping an 11:1 cr. Flows better (not quite as good as the 885 head), and can take advantage of the "i" intake. Only downside is the smaller valves.



                        While the combination should be sound, the 10.2:1 pistons are still dished, not so much as the standard eta pistons. When paired with the 885 "i" head, you should see something in the neighborhood of 9.5:1. The only drawback is that the pistons do not match the combustion chamber of the head, and may leave a few HP on the bench as a result.

                        Given a choice between the two, I'd choose the 10.2:1 pistons with the 731 head. That at least gives me some options when at the pump!
                        I assume you are talking about octane. What would be necessary for the 11:1 setup?
                        Also, would any special engine management be necessary? Or just some 2.7I software?

                        Comment


                          Originally posted by mooseheadm5 View Post
                          You do not have to drill squat in a super eta head. It already has a 7 bearing cam since it is an i head, the only difference is the cam profile and the dual springs. However, you cannot (easily) replace the springs without pulling the head, which is fine since your head gasket is probably old and could stand to be replaced.
                          I have learned something new the other day. Regardless of what the parts catalog says, if your super eta was made from 3/87-8/87, you may have the 4 bearing super eta cam and you will have to drill the bearings if you want to use the i cam. If your super eta is 9/87 on, it has a 7 bearing cam. I have spoken to someone that did the i cam swap on a late super eta, and he claimed the power increase was negligible, but IIRC, he did not do the full i swap. There you have it.
                          -P

                          Moosehead Engineering

                          Comment


                            Originally posted by mooseheadm5 View Post
                            I have learned something new the other day. Regardless of what the parts catalog says, if your super eta was made from 3/87-8/87, you may have the 4 bearing super eta cam and you will have to drill the bearings if you want to use the i cam. If your super eta is 9/87 on, it has a 7 bearing cam. I have spoken to someone that did the i cam swap on a late super eta, and he claimed the power increase was negligible, but IIRC, he did not do the full i swap. There you have it.
                            haha YES! Mine's 9/87 :)



                            Okay motronic 1.3 wizards I have a question for you. I found a mostly clean shell I want to put my engine in for a good price, but it's an 85 eta. How hard would it be to put the m1.3 system from an I in it with my super-eta motor? I'm completely confident in being able to do the swap other than that part, well even if I have to splice every wire in the harness I know I can still do it I just don't really want to. Will it be mostly plug and play since I'm using a m1.3 engine AND ecu? Or will I have to do a ton of cutting up of the harness?

                            I'd possibly like to even put the 85 eta motor in my 88 after and sell the car but that's technically not legal in CA.

                            Comment


                              bump this back with this weird question

                              I have 1986 325es with 230k miles or around (manual). I also have this 1988 325is car also with only 133k miles (autotragic).

                              easier for me to swap whole motor from 88 to my 86? or its easier for me to do I-head conversion? I know I wouldn't use some of harness on the motor because of auto.

                              Thanks.

                              Comment


                                Do the "i" head swap. It is far easier. The only thing that will cause you some difficulty is adapting the '88 "i" harness to the '86 fusebox. (IIRC, the '86 still uses the rectangular C101. The '88 has the large round C101.)

                                When converting to M1.3, you can leave the block in place, only having to remove the head. (And everything attached!) If you chose to swap the entire engine, you'll still have to resolve the C101 connections, as well as remove even more from your engine bay.

                                As far as the differences betwen the manual and automatic, I don't belive there are any differences betwen the two engine harnesses. I know there are no differences in the Motronic 1.3 ECU. (Kickdown cable on the throttle body. I think that's all.)

                                Since you have both vehicles, you have all the needed parts. The question remains, is there something wrong with either vehicle that forces the swap , or are you looking to consolidate driveway space? :)

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