Announcement

Collapse
No announcement yet.

E30 Stroker 2.7L CA Smog Questions

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    E30 Stroker 2.7L CA Smog Questions

    I recently bought an M20B25 engine with about 165k on it. The plan with this build is to complete an engine overhaul and then find a decent E30 to swap the engine into. I've got it pulled apart and am cleaning and replacing all the bolts, pumps, and brackets. However, I feel I am at a major crossroads with this engine. I was planning on going with a standard M20B25 bottom end with a Bimmerheads Super Sport head with the 274 cam. After reading a ton of material on strokers, I might be interested in a M20B27 bottom end and the M20B25 head. The main BUT in this whole idea is I live in California and must comply with the stringent smog laws. I know the policy is if it looks stock there is no reason they can fail you. Before I make an expensive leap, I need some guidance. So, my questions are as follows:

    Has anyone had a 2.7L stroker in California and been able to pass smog?

    What do I need to do electronically to make it pass smog?

    Will I have to pull everything off every two years to pass smog? (Frowning on this because I had to do this on my E36 M3)

    Will the Super Sport head from Bimmerheads and the stroker even pass smog?

    What are the differences between the 2.7 block and the 2.5 block and will all of the accessories be the same?

    Are things like the oil pan different between the 2.7 and the 2.5?

    Are the gaskets the same between these engines?

    Does an early model 2.7 fit a later model 2.5 head?

    Any advice and leads on posts are appreciated. Thanks in advance.

    #2
    Originally posted by Rockonp04 View Post
    I recently bought an M20B25 engine with about 165k on it. The plan with this build is to complete an engine overhaul and then find a decent E30 to swap the engine into. I've got it pulled apart and am cleaning and replacing all the bolts, pumps, and brackets. However, I feel I am at a major crossroads with this engine. I was planning on going with a standard M20B25 bottom end with a Bimmerheads Super Sport head with the 274 cam. After reading a ton of material on strokers, I might be interested in a M20B27 bottom end and the M20B25 head. The main BUT in this whole idea is I live in California and must comply with the stringent smog laws. I know the policy is if it looks stock there is no reason they can fail you. Before I make an expensive leap, I need some guidance. So, my questions are as follows:

    Has anyone had a 2.7L stroker in California and been able to pass smog?

    What do I need to do electronically to make it pass smog?

    Will I have to pull everything off every two years to pass smog? (Frowning on this because I had to do this on my E36 M3)

    Will the Super Sport head from Bimmerheads and the stroker even pass smog?

    What are the differences between the 2.7 block and the 2.5 block and will all of the accessories be the same?

    Are things like the oil pan different between the 2.7 and the 2.5?

    Are the gaskets the same between these engines?

    Does an early model 2.7 fit a later model 2.5 head?

    Any advice and leads on posts are appreciated. Thanks in advance.
    don't know what's involved in SMOG but go easy on the cam and a proper tune is all you need to consider really for tailpipe emissions

    blocks are for all intensive purposes the same, different blocks have different main bearing tangs which is a not a 2.7 vs 2.5 thing more the age and some have an additional rear Welch plug

    steer clear of a 2.7 bottom end and b25 head, a 2.7 based "i" engine is a better option.

    if you have a good core then get the head refresh by a competent shop in the area it will save you a bunch which is better spent on ecu and tuning.
    89 E30 325is Lachs Silber - currently M20B31, M20B33 in the works, stroked to the hilt...

    new build thread http://www.r3vlimited.com/board/showthread.php?t=317505

    Comment


      #3
      Originally posted by digger View Post

      don't know what's involved in SMOG but go easy on the cam and a proper tune is all you need to consider really for tailpipe emissions

      blocks are for all intensive purposes the same, different blocks have different main bearing tangs which is a not a 2.7 vs 2.5 thing more the age and some have an additional rear Welch plug

      steer clear of a 2.7 bottom end and b25 head, a 2.7 based "i" engine is a better option.

      if you have a good core then get the head refresh by a competent shop in the area it will save you a bunch which is better spent on ecu and tuning.
      I've been seeing the "2.7i engine" term thrown around. What does 2.7i mean?

      Comment


        #4
        Originally posted by digger View Post

        don't know what's involved in SMOG but go easy on the cam and a proper tune is all you need to consider really for tailpipe emissions

        blocks are for all intensive purposes the same, different blocks have different main bearing tangs which is a not a 2.7 vs 2.5 thing more the age and some have an additional rear Welch plug

        steer clear of a 2.7 bottom end and b25 head, a 2.7 based "i" engine is a better option.

        if you have a good core then get the head refresh by a competent shop in the area it will save you a bunch which is better spent on ecu and tuning.
        I've heard good things about using the 2.7 block with 130mm rods and Seta pistons with the B25 head. Can you elaborate on the cons?

        Comment


          #5
          Forget the seta pistons. They were a one year only thing, and was 8.5:1 vs the b25's 8.8:1.

          2.7i is in reference to adding an 885 head to an ETA rotating assembly. Unless you are starting with an ETA, this is less powerful than a than a stock b25.

          To build a stroker in a budget, use b25 pistons, and b27 crank/rods with 2mm shaved off the block deck -or- b25 pistons with 84mm crank (from m52b28 or m54b28) and 130mm rods (ETA) and .5mm shaved off the block.

          Your passing emissions will have more to do with tuning than hardware, as long as you select a proper cam as mentioned. Too much overlap/duration for the selected compression will bleed contaminates into the exhaust.

          john@m20guru.com
          Links:
          Transaction feedback: Here, here and here. Thanks :D

          Comment


            #6
            Originally posted by ForcedFirebird View Post
            Forget the seta pistons. They were a one year only thing, and was 8.5:1 vs the b25's 8.8:1.

            2.7i is in reference to adding an 885 head to an ETA rotating assembly. Unless you are starting with an ETA, this is less powerful than a than a stock b25.

            To build a stroker in a budget, use b25 pistons, and b27 crank/rods with 2mm shaved off the block deck -or- b25 pistons with 84mm crank (from m52b28 or m54b28) and 130mm rods (ETA) and .5mm shaved off the block.

            Your passing emissions will have more to do with tuning than hardware, as long as you select a proper cam as mentioned. Too much overlap/duration for the selected compression will bleed contaminates into the exhaust.
            Will shaving off 2mm of the block alter timing? I also heard, the b25 pistons will have to machined to clear the b27 crank. Are the m52b28 or m54b28 cranks and the 130mm rods hard to come by?

            Comment


              #7
              b25 pistons clear the eta crank just fine. The larger cranks (84mm+) need either the pistons or crank modified for clearance.

              Yes, shaving the block will alter timing a little, but nothing to be worried about. Even with a stock cam, they are good for 175-180whp.

              See here: https://www.r3vlimited.com/board/for...52#post7038352
              john@m20guru.com
              Links:
              Transaction feedback: Here, here and here. Thanks :D

              Comment


                #8
                If you have a proper tune and a functioning / fresh catalytic converter, you will be fine. I've been passing the tailpipe sniffer with flying colors for nearly a decade with my 2.1L M42 (11.5:1 CR, hotter cams, larger injectors, etc), and for the first few years it even had sort of a bogus tune in it, but I put a fresh Magnaflow weld-in cat on. I assume the M20 cat is a little bigger and more costly, but a CA-legal Magnaflow one for the M42 is like $275 installed. If you are still running the original one, consider replacing it. The OEM one is not CA legal, so you have to go aftermarket.

                The real ass kicking with SMOG comes from the visual inspection. Some shops are rigorous about it, some are not. A LOT of stuff under my hood is clearly not stock, but the car blows clean and has a properly maintained evaporative emissions system, so I pass. If everything outside of the engine looks original, you are 75% of the way there.

                Transaction Feedback: LINK

                Comment


                  #9
                  had a SETA/I . M50 injectors and a MarkD Tune, Passed smog with Flying colors.

                  Comment


                    #10
                    i feel your pain,Ive invested so much money into this next stroker, i really hope it blows clean for the sniffer, as you stated, i have a smog tech that will pass it if it blows clean, ForcedFirebird is actually the one building this stroker for me, 84mm crankshaft /I pistons
                    ill let you know how it goes when its all said and done,

                    Comment


                      #11
                      I had a conversation with Ireland Engineering in Duarte, CA and my questions were pretty much answered. They have been doing these for a long time and have all the kinks worked out. Their thoughts were the 2.8l stroker with a 272 cam, M20B25 block, 885 M20B25 head, M20B27 crank, Ireland Custom Pistons, upgraded injectors (either 17lb or 19lb), custom tune chip from Enhanced Automotive Technology, stainless steel valves, new OEM springs, and a new cat should pass with flying colors. They recommended Steve's Machine Shop in Azusa. It's amazing what you can find out in a day when you talk to someone who has been doing this for decades.

                      If anyone has any other advice I am all ears.

                      Comment


                        #12
                        ^^^that would be a 2.7, though, and the combination I mentioned above with the exception of using stock pistons and shaving the block vs custom pistons. Even boring it out to 85mm and using a 81mm (b27) crank it only displaces 2757cc.

                        Also, you don't "need" upgraded injectors. The stock injectors are actually quite supportive. I have gotten 255whp in a client car at work from stock m50 injectors/ECU, and there was room to grow. I have built many variations similar to what IE told you, and they typically make about 175-180whp and use stock injectors (176 & 180 in our two race cars to be exact). A chip might not even be totally necessary, the 176hp car uses a stock ECU and actually ran fine on the stock chip (9.4:1 m20b27 with 272 cam), but made about 8whp more once the chip was remapped on the dyno.
                        john@m20guru.com
                        Links:
                        Transaction feedback: Here, here and here. Thanks :D

                        Comment


                          #13
                          I'm sure I could use the stock injectors but I am trying to get as much power out of this car as possible. This will be a forever build and I want to do it right the first time, so spending the extra dough on injectors and a chip isn't a huge deal. But its good to know I can use the stock injectors in case i need to step it back down

                          Comment


                            #14
                            Injectors won't change the power output, that's a common misconception. The only reason you should ever need larger injectors is when you reached maximum duty cycle.
                            john@m20guru.com
                            Links:
                            Transaction feedback: Here, here and here. Thanks :D

                            Comment


                              #15
                              Originally posted by ForcedFirebird View Post
                              Injectors won't change the power output, that's a common misconception. The only reason you should ever need larger injectors is when you reached maximum duty cycle.
                              What is the duty cycle of the stock injectors in the 2.7/2.8 stroker

                              Comment

                              Working...
                              X