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    • PAW Motorsport offers N54 ported/polished cylinder head upgrade - $3995

      PAW Motorsport is offering a cylinder head upgrade for N54 based BMW vehicles. There is a substantial gain in port flow velocity without a sacrifice in low lift situations. Flowbench charts show an increase of about 35% with gains from 161 cfm to 227 cfm. Both intake and exhaust ports have been ported and polished along with modified intake and exhaust valves. The claimed power gains with the head alone are in the 40 hp range. Charts and pictures are below.

      Expect before and after results on a PAW DCT N54 project car in the next few weeks. For those interested in this upgrade there is a core charge in the $2800 range which obviously is refunded when the core is received.














      Further Details:








      Charts and Data:







      This article was originally published in forum thread: PAW offers N54 ported cylinder head upgrade - $3995 started by Sticky View original post
      Comments 325 Comments
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by DBFIU Click here to enlarge
        Think of it this way, if the rod was 10 feet long all else being the same; what would be the maximum angle it would make with the crank during operation? It will be nearly zero or maybe a few degrees at most.

        The longer the rod the smaller the angle and less side loads. But, it does have it's disadvantages. Because the rod is pointing in one direction (remember the small angle now?) almost all the time, the crank doesnt see the maximum torque it could possibly get, only when the crank is mid throw ( at 90 degrees) will it see maximum torque production during rotation. Having a steeper angle transfers torque to the crank for a longer period of time which can be beneficial (but you dont want too much side load).
        Click here to enlarge

        Just messing, what you are saying makes sense.
      1. DBFIU's Avatar
        DBFIU -
        lol ^ that reminds me of school...

        Too bad I've been doing that for a living for years now, I thought after graduation I wouldn't have to touch it...

        it just got worse.


        vodka helps though
      1. 654's Avatar
        654 -
        Click here to enlarge Originally Posted by DBFIU Click here to enlarge
        But don't you want to increase the rod length to decrease the angle the rod makes with crank centerline thus reducing the side load component vector?
        Yes, longer rods are more favourable.
      1. DBFIU's Avatar
        DBFIU -
        Click here to enlarge Originally Posted by 654 Click here to enlarge
        Yes, longer rods are more favourable.

        THAT'S WHAT SHE SAID



        YEEEAAAAAA
      1. Terry@BMS's Avatar
        Terry@BMS -
        Click here to enlarge Originally Posted by DBFIU Click here to enlarge
        lol ^ that reminds me of school...

        Too bad I've been doing that for a living for years now, I thought after graduation I wouldn't have to touch it...

        it just got worse.


        vodka helps though
        It seemed there was no end to the math and physics courses I had to take for computer science. I enjoyed the physics but hated the math. Once I graduated aside from one Lorentz transform for a graphics program and a few point of inflection formulas haven't touched any of it. Click here to enlarge
      1. 654's Avatar
        654 -
        Any reviews on these?
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by 654 Click here to enlarge
        Any reviews on these?
        Don't think anybody on the board has this upgrade yet.
      1. Forced Air's Avatar
        Forced Air -
        maybe i missed it....but reading PAW's site made it sound like they are claiming 40 hp with nothing else done....Does anyone know if this head has been dynoed, and if so with what mods....it sounds like many are assuming 40 hp with full bolt-ons. But that isn't the impression I got from reading the PAW site.
      1. 5mall5nail5's Avatar
        5mall5nail5 -
        Is this a CNC port job? If not, how are they keeping them uniform?
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Forced Air Click here to enlarge
        maybe i missed it....but reading PAW's site made it sound like they are claiming 40 hp with nothing else done....Does anyone know if this head has been dynoed, and if so with what mods....it sounds like many are assuming 40 hp with full bolt-ons. But that isn't the impression I got from reading the PAW site.
        Yep, 40 crank with the head alone.

        I think I posted dynos somewhere? I'll have to look.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by 5mall5nail5 Click here to enlarge
        Is this a CNC port job? If not, how are they keeping them uniform?
        I don't know, good question to ask them.
      1. LostMarine's Avatar
        LostMarine -
        im not paying 5k for heads, sorry, not happening.. im going elsewhere Click here to enlarge
      1. Forced Air's Avatar
        Forced Air -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Yep, 40 crank with the head alone.

        I think I posted dynos somewhere? I'll have to look.
        So why is everyone quoting $4k for 20 hp?

        Figure if say LostMarine picked these up he would be getting far more the 40 hp...at his level I would expect more like 60 or so whp with a reduction in psi (which, given fuel, could be turned back up for more power). If the data from PAW is anything to go by.
      1. lamia2super's Avatar
        lamia2super -
        Click here to enlarge Originally Posted by LostMarine Click here to enlarge
        im not paying 5k for heads, sorry, not happening.. im going elsewhere Click here to enlarge
        where are you going huh huh?? lol
      1. 654's Avatar
        654 -
        Click here to enlarge Originally Posted by Forced Air Click here to enlarge
        So why is everyone quoting $4k for 20 hp?

        Figure if say LostMarine picked these up he would be getting far more the 40 hp...at his level I would expect more like 60 or so whp with a reduction in psi (which, given fuel, could be turned back up for more power). If the data from PAW is anything to go by.
        It's not quite so clear. I believe the stock turbo housings will become the restriction at LM's level and there is a limit how much air can be pushed through them. So basically it could well be e.g. "only" 45whp or so Click here to enlarge
      1. 654's Avatar
        654 -
        Click here to enlarge Originally Posted by LostMarine Click here to enlarge
        im not paying 5k for heads, sorry, not happening.. im going elsewhere Click here to enlarge
        where are you going now?
      1. LostMarine's Avatar
        LostMarine -
        Details will come when gears are actually in motion Click here to enlarge
      1. Forced Air's Avatar
        Forced Air -
        Click here to enlarge Originally Posted by 654 Click here to enlarge
        It's not quite so clear. I believe the stock turbo housings will become the restriction at LM's level and there is a limit how much air can be pushed through them. So basically it could well be e.g. "only" 45whp or so Click here to enlarge
        Could be....but with just the heads (no increase in boost)...the volumetric efficiency increases drastically given the published numbers. So manifold pressure will drop significantly for the current amount of air the turbos are moving. Which will allow also allow the turbos to work more efficiently because they are pushing against less dense air....So even if the stock housing are at their limit (which they likely aren't given the fuel system has been found to be the major limitation) you still gain a lot just from efficiency even if the same volume passes through the turbos. Cooler air, faster spool, less restriction etc...especially at high rpm where a lot more air will be able to get in per cycle due to the valve job.
      1. 5mall5nail5's Avatar
        5mall5nail5 -
        Click here to enlarge Originally Posted by Matt@Camber-Toe Click here to enlarge
        To rev it higher you'd need a shorter rod to avoid more side load on the rings..
        Incorrect. A longer rod prevents side loading. Shorter rod would put more load on the walls and sides of pistons.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by 5mall5nail5 Click here to enlarge
        Incorrect. A longer rod prevents side loading. Shorter rod would put more load on the walls and sides of pistons.
        Yes, longer rod reduces the max rod angle.

        I think what he was saying though was a shorter stroker will have lower piston speed allowing you to rev higher.