• Weistec releases CNC ported/polished M156 (C63 AMG) aftermarket heads 50+ hp gains, $4895

      Weistec has released CNC ported heads for the Mercedes M156 6.2 liter V8 engine. Weistec claims this is the first head solution although we believe MHP had an option available first. Regardless, claim is a 40-50 horse gain on naturally aspirated motors and 70-80 on supercharged motors. No dynos released but flow charts are below.

      Key Features:
      5-axis CNC machined
      397.88 CFM Intake flow
      257.81 CFM Exhaust flow
      Fully assembled, Read to run heads
      Custom ground factory 40mm intake valves
      Custom ground factory 33mm exhaust valves

      Heads can add an extra 40-50 HP on naturally aspirated engines, and up to 70 HP on supercharged engines with stock cam shafts.

      $4,895 with core exchange.

      Supported Platforms
      2007-2010 S63 AMG
      2007-2011 ML63 AMG
      2007 R63 AMG
      2007-2008 CLK63 AMG
      2008 CLK63 Black Series
      2007-2010 CLS63 AMG
      2008-Present C63 AMG (Sedan and Wagon)
      2007-Present E63 AMG (Sedan and Wagon)
      2008-2010 CL63 AMG
      2009-Present SL63 AMG













      This article was originally published in forum thread: Weistec Releases Heads started by DD GT3 RD View original post
      Comments 47 Comments
      1. MHP LLC's Avatar
        MHP LLC -
        Click here to enlarge Originally Posted by DD GT3 RD Click here to enlarge
        If there was a hood that let it fit, could you use the SLS heads?
        You can use SLS heads with a M156 intake manifold, they have 40mm int. valves and 34mm exhaust valves vs 40/33 for M156 heads, however ported M156 heads will flow better than stock SLS heads, so it's kind of a toss up as to which is more cost effective. Ported SLS heads would be the way to go but also the most expensive and we are talking about Maybe 10-15hp difference. The castings are just so good from the factory.

        also, how does the SLS get the extra power over the C63 ? I know my car supposedly has parts from the SLS...but is the extra power on the SLS just do to intake/heads and ecu? seems like some of the parts could be used on our engines, no? or is the whole set up just different and nothing really transfers over?
        It has over 170 changes, dry sump, cams, rotating assembly, heads, intake manifold, TB placement, exhaust manifolds, etc. SLS's actually make 600HP stock. A good tune will net another 35HP+ or so. SLS is a 2013 viper chassis essentially so there's a lot more room under that hood plus the dry sump lowers the engine enough that the taller manifold fits. The rot assembly (crank, pistons, rods, rings) is .5 kilo lighter with P31/SLS bottom end vs M156 but static CR is the same 11.3:1 so all the power comes from software not the bottom end. Heads, cams will work but that's about it hardware wise.
      1. MHP LLC's Avatar
        MHP LLC -
        Click here to enlarge Originally Posted by I am Jeff Click here to enlarge
        Andy. I'm glad you're able to voice yourself here! In the other forum, it would have either deleted or the thread is locked.
        Thanks Jeff, it's nice to be able to speak ones mind. Click here to enlarge
      1. 600whp S4's Avatar
        600whp S4 -
        Click here to enlarge Originally Posted by MHP LLC Click here to enlarge
        Thanks Jeff, it's nice to be able to speak ones mind. Click here to enlarge


        I love the info thanks for clearing it up. what do your billet cams add hp wise? Seems to me a set of cams and nitrous is the only way to go on these cars(aside from long tubes and a tune)
      1. MHP LLC's Avatar
        MHP LLC -
        Click here to enlarge Originally Posted by 600whp S4 Click here to enlarge
        I love the info thanks for clearing it up. what do your billet cams add hp wise? Seems to me a set of cams and nitrous is the only way to go on these cars(aside from long tubes and a tune)
        Hard to say yet, based on the dimensions of the smallish stock cams (ridiculously small really) and our changes 60-80HP is realistic assuming the car already has our LTs/Mids.

        Thanks
      1. 600whp S4's Avatar
        600whp S4 -
        Click here to enlarge Originally Posted by MHP LLC Click here to enlarge
        Hard to say yet, based on the dimensions of the smallish stock cams (ridiculously small really) and our changes 60-80HP is realistic assuming the car already has our LTs/Mids.

        Thanks
        damn why did dad uninstall his?
      1. DLV-Engineering's Avatar
        DLV-Engineering -
        Air speed numbers? It can flow great CFM but have horrible air speed through certain areas in the port. Thats something that needs to be watched.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by TaZaM3 Click here to enlarge
        Just shut up already....
        Taza, please cut it out. He is just saying he wants the claims to be backed up.

        I want the claims backed up as well.

        There isn't any bashing, you would say the same if someone released an S54 product claiming large numbers without any support.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by 600whp S4 Click here to enlarge
        damn why did dad uninstall his?
        Good question.
      1. TaZaM3's Avatar
        TaZaM3 -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Taza, please cut it out. He is just saying he wants the claims to be backed up.

        I want the claims backed up as well.

        There isn't any bashing, you would say the same if someone released an S54 product claiming large numbers without any support.
        Although this turned out better then the supercharger thread, I do believe they are purposely negatively commenting on threads about competitor's products which is distasteful as a a professional company... The way they posted on the supercharger thread was just horrible, so my posts on this thread are still undergoing from that thread. Anyways I let it go and refrained from talking even after more insults were thrown at me but you brought it up again. So in fact I had cut it out until you brought it back up, thanks.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by TaZaM3 Click here to enlarge
        Although this turned out better then the supercharger thread, I do believe they are purposely negatively commenting on threads about competitor's products which is distasteful as a a professional company... The way they posted on the supercharger thread was just horrible, so my posts on this thread are still undergoing from that thread. Anyways I let it go and refrained from talking even after more insults were thrown at me but you brought it up again. So in fact I had cut it out until you brought it back up, thanks.
        I'll try to respond to posts more on your time table than when I see them but glad we can drop this. Hopefully Weistec provides numbers to substantiate the claims.
      1. MHP LLC's Avatar
        MHP LLC -
        Click here to enlarge Originally Posted by 600whp S4 Click here to enlarge
        damn why did dad uninstall his?
        Couldn't wait for the tuning, wanted to race too bad. Don't blame him it's taken us much longer than we anticipated.
      1. MHP LLC's Avatar
        MHP LLC -
        In case anyone was wondering about Ford 4v heads Click here to enlarge, it was written in late 2004 and is still the most comprehensive and accurate guide to date for Modular 4 valves :

        http://www.mustang50magazine.com/tec...ide/index.html
      1. 600whp S4's Avatar
        600whp S4 -
        Click here to enlarge Originally Posted by MHP LLC Click here to enlarge
        Couldn't wait for the tuning, wanted to race too bad. Don't blame him it's taken us much longer than we anticipated.

        so we might see a 9 sec pass with a 160shot and cams?
      1. MHP LLC's Avatar
        MHP LLC -
        Finally here are pics of our heads, you can see clear differences vs the CNC port in the valve guides, around the guides, in the throats, bowls, chambers, and in the shape of the ports. Pretty much everything is different.

        Click here to enlarge

        Click here to enlarge

        Click here to enlarge

        Click here to enlarge

        Click here to enlarge

        Yes that's my Serdi in the last pic TaZa Click here to enlarge
      1. MHP LLC's Avatar
        MHP LLC -
        Also keep in mind that peak lift with stock M156 cams is around .450"
      1. Exeenom's Avatar
        Exeenom -
        40 to 50 hp gain does seem like a little bit too much especially on a very well made piece of hardware. It'd be interesting to see if Weistec will indeed backup their claims with before and after dyno graphs.
      1. DD GT3 RD's Avatar
        DD GT3 RD -
        MHP have you put these heads on a motor with stock headers/exhaust? What do you think the gains would be with stock headers exhaust or is a waste without doing full exhaust?
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by MHP LLC Click here to enlarge
        Finally here are pics of our heads, you can see clear differences vs the CNC port in the valve guides, around the guides, in the throats, bowls, chambers, and in the shape of the ports. Pretty much everything is different.

        http://www.bimmerboost.com/images/im...010/02/534.jpg

        http://www.bimmerboost.com/images/im...010/02/536.jpg

        http://www.bimmerboost.com/images/im...010/02/538.jpg

        http://www.bimmerboost.com/images/im...010/02/535.jpg

        http://www.bimmerboost.com/images/im...010/02/537.jpg

        Yes that's my Serdi in the last pic TaZa Click here to enlarge
        What is the difference between your approach to the heads and Weistec's?
      1. MHP LLC's Avatar
        MHP LLC -
        Click here to enlarge Originally Posted by DD GT3 RD Click here to enlarge
        MHP have you put these heads on a motor with stock headers/exhaust? What do you think the gains would be with stock headers exhaust or is a waste without doing full exhaust?
        Never tried it on a stock exhaust car, it would be a waste IMO no question.
      1. MHP LLC's Avatar
        MHP LLC -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        What is the difference between your approach to the heads and Weistec's?
        Pretty much everything, valve angles, port shapes/contours/sizes, quality of short/long turns, bowl blending, etc. I think they remove more material than we do and we leave the guides longer for longer valvetrain life and stability, mowing them down isn't worth 8-10cfm there are other ways to gain and N/A it's about velocity. That being said most of these heads will be paired with their superchargers so the extra port size won't matter as much due to the blower supplying the velocity.