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    Holy crap, thanks! So much good information I needed.

    I think the only thing that I am missing from that is if I need to deck the block the ~2mm he suggests in order to get the CR he talks about. He doesn't follow up on how decking the block changes the CR before and after it appears.

    I have a 1990 325i and a 1986 325e I am mating together so it sounds like I'll be at 9.5:1 CR using 325i pistons which is great... unless it decking the block is required and I really don't want to deal with that.
    Last edited by LovelessAndroid; 04-08-2017, 01:45 PM.

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      Correct that would be with decking
      Swanny!
      SUCKERS.

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        Cp101

        Ok....I made it to page 12....so I'm just going to ask....what I got is a 87 325e chassis just dropped in a 88 m20b25 with harness....getting spark and fuel pressure....but injectors won't open....everything checks out ....but what about cp101 plug is there any pins that need swapped around ?

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          So do you happen to know what the CR using 325i pistons without decking the block is then? Is it almost stock like 8.75:1 or still above 9:1?

          I'd really like to get as close to 10 as possible... sounds like if I don't want to do any machining I should swap my 885 head directly onto the ETA block and not swap pistons and try to find a thin head gasket. This appears to give me a 9.4:1 and with the higher displacement and without machining or bottom end disassembly.

          Or I could try to find a set of early 325i pistons which without decking the block looks like it would get me to around 10:1. But they then need machining... and I also really don't want to drop a grand on custom forged pistons.

          Or are there any stock 132mm conrods? Haha that'd be too easy.

          If my donor car is a 1986 I wonder if there is any chance its an early high compression ratio one... that would be super lucky.

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            Originally posted by LovelessAndroid View Post
            So do you happen to know what the CR using 325i pistons without decking the block is then? Is it almost stock like 8.75:1 or still above 9:1?

            I'd really like to get as close to 10 as possible... sounds like if I don't want to do any machining I should swap my 885 head directly onto the ETA block and not swap pistons and try to find a thin head gasket. This appears to give me a 9.4:1 and with the higher displacement and without machining or bottom end disassembly.

            Or I could try to find a set of early 325i pistons which without decking the block looks like it would get me to around 10:1. But they then need machining... and I also really don't want to drop a grand on custom forged pistons.

            Or are there any stock 132mm conrods? Haha that'd be too easy.

            If my donor car is a 1986 I wonder if there is any chance its an early high compression ratio one... that would be super lucky.


            http://www.r3vlimited.com/board/showthread.php?t=193894 is another good thread for piston rod crank combos
            Swanny!
            SUCKERS.

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              Originally posted by Bulldog View Post
              Ok....I made it to page 12....so I'm just going to ask....what I got is a 87 325e chassis just dropped in a 88 m20b25 with harness....getting spark and fuel pressure....but injectors won't open....everything checks out ....but what about cp101 plug is there any pins that need swapped around ?


              Which harness do you have and what ECU? Its possible with the late harness the injector connection has corrosion causing firing issues. Are you sure fuel is getting into and through the rail?

              I had to jump a relay to get my fuel flowing properly in my 87is. Took time with the ETM chasing down wires to get it all sorted out since they're a weird in between model.
              Swanny!
              SUCKERS.

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                It's 88 harness and I'v checked every connection cleaned and used tons of eletric grease.....running a 173 dme

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                  Originally posted by Swanny View Post
                  http://www.r3vlimited.com/board/showthread.php?t=193894 is another good thread for piston rod crank combos
                  So they immediately list the 2.7 stroker as ETA block, rods, and SETA pistons... however on Strictly ETA's website it shows the compression ratio of a stock SETA as 8.5:1. According to E30zone wiki, swapping an 885 head directly onto an ETA block will yield 9.4:1.

                  Why does the "default" stroker build use SETA pistons?

                  There appears to be a lot of conflicting advice between Strictly ETA and E30Zone, especially with the results of using 325e pistons with the 325i head...

                  I also like the idea of using the M52 crank with my 325i pistons which yields a 2.8L stroker, and the M52 crank can be found readily for under $100 and the price of a crank spacer. (Oh lawdy, just saw the price for the MM crank spacer... $200. Anyone selling one?!) Someone lists that combination as 9.3:1 without decking the block, 9.7:1 with the decking... so again I'm still in the same CR range of just swapping the 885 head onto the stock ETA block BUT I get to 2.8L.

                  Would decking the block 0.5mm require an adjustable cam gear? Or can I get away with it since I want to go to MSPNP and can adjust my ignition tables that way? It appears that I would need one.
                  Last edited by LovelessAndroid; 04-09-2017, 08:22 AM.

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                    In this thread digger touches on some good points
                    Swanny!
                    SUCKERS.

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                      Originally posted by Bulldog View Post
                      It's 88 harness and I'v checked every connection cleaned and used tons of eletric grease.....running a 173 dme


                      Get the ETM for 87 and 88 and go side by side. Probe test with a multimeter to be sure you have power where you need it.
                      Swanny!
                      SUCKERS.

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                        Originally posted by Swanny View Post
                        In this thread digger touches on some good points
                        http://www.r3vlimited.com/board/showthread.php?t=304600
                        I've officially gone down the rabbit hole for the stroker build...

                        I am liking the 2.8L M52 more and more since I have all of the expensive parts and just need the crankshaft and spacer.

                        However, I have a follow up question too... instead of getting an IE 272 regrind or a Bimmerheads 274 regrind, if I run the stock cam will that yield the most low-end torque? Or should I at least aim for a 270 to make the most of it?

                        I stumbled upon the 2.8 article on E30wiki and it is pretty great.

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                          tagged

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                            So I have a 87 I harness, is it completely plug and play? From what I've been reading it sounds like I'll still have to change the c101 connector wiring. Should I just cut the old plug off my eta harness and wire it to my new "I" harness? Thanks in advance.

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                              Originally posted by RichiesE30 View Post
                              So I have a 87 I harness, is it completely plug and play? From what I've been reading it sounds like I'll still have to change the c101 connector wiring. Should I just cut the old plug off my eta harness and wire it to my new "I" harness? Thanks in advance.


                              What year is the shell?
                              Swanny!
                              SUCKERS.

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                                Originally posted by Swanny View Post
                                What year is the shell?


                                87 eta shell


                                Sent from my iPhone using Tapatalk

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