• 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 dzenno Click here to enlarge
        seriously Click here to enlarge i've emailed on 3 separate occasions...first time they sent me the specs even but then later on nothing...

        i guess i'll call them but now with VAC just around the corner I have to see first what they've got in store and wait for my next impulsive purchase moment lol
        Absolutely evaluate VAC's option but seriously, please give PAW a call.
      1. LostMarine's Avatar
        LostMarine -
        VAC stg 3 heads vs PAW heads

        Attachment 9618
      1. dzenno@PTF's Avatar
        dzenno@PTF -
        nice LM...both of them look great but man they look totally different in what they'll provide and how they deliver...PAW has just slightly higher flow up top but considerably lower than VAC down low...VAC seems like a torque monster while PAW seems it might enjoy high RPMs more...what do you guys think?
      1. LostMarine's Avatar
        LostMarine -
        i dunno, i just have data thats been in my email for a few weeks now and im trying to catch up on what i missed
      1. 654's Avatar
        654 -
        Note the differences in their "stock" figures.

        What about exhaust?

        Did VAC upgrade the exh valves? Price?

        Torque we have enough...
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by dzenno Click here to enlarge
        nice LM...both of them look great but man they look totally different in what they'll provide and how they deliver...PAW has just slightly higher flow up top but considerably lower than VAC down low...VAC seems like a torque monster while PAW seems it might enjoy high RPMs more...what do you guys think?
        Where you really need to focus on this motor is up top.
      1. LostMarine's Avatar
        LostMarine -
        Click here to enlarge Originally Posted by 654 Click here to enlarge
        Note the differences in their "stock" figures.

        What about exhaust?

        Did VAC upgrade the exh valves? Price?

        Torque we have enough...
        no idea, can you explain what you mean by the variation in stock figures? i see the difference, but what does each side of it say?
      1. dzenno@PTF's Avatar
        dzenno@PTF -
        also just because one has higher flow numbers in a certain area doesn't mean jack when you actually go and run it UNLESS they also ran it and saw advantages of more vs. less porting...only once these are bolted up and tuned with will we know really what's going on...for all we know at this time, they look great on paper, will for sure deliver more power BUT how and in what way remains to be seen, at least to my very untrained eye
      1. oddjob2021's Avatar
        oddjob2021 -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Where you really need to focus on this motor is up top.
        exactly right sticky, this car has enough torque as is, and the only people that will, or should be interested in this will be uppd chra (and definitely when they come, -single) turbo guys and with them you shift at redline instead of short shifting due to power drop off/taper. up top is the way to go, the n54 does not need more down low is for sure!
      1. 654's Avatar
        654 -
        Click here to enlarge Originally Posted by LostMarine Click here to enlarge
        no idea, can you explain what you mean by the variation in stock figures? i see the difference, but what does each side of it say?
        I mean what the companies refer to as "stock head flow figures" are not the same. So, I believe their stock figures come from a used car before working on the head, and they might be a bit different due to the carbon build up or then there could be differences in how the flow bench reads the flow. In any case calculating the percentual increases in the flow, should rule out some variation.
      1. PEI330Ci's Avatar
        PEI330Ci -
        Click here to enlarge Originally Posted by dzenno Click here to enlarge
        also just because one has higher flow numbers in a certain area doesn't mean jack when you actually go and run it UNLESS they also ran it and saw advantages of more vs. less porting...only once these are bolted up and tuned with will we know really what's going on...for all we know at this time, they look great on paper, will for sure deliver more power BUT how and in what way remains to be seen, at least to my very untrained eye
        Wise statement.

        Making power isn't just about flow....it can be a lot about mixture preparation as well. (Especially with DI) I've actually seen restrictors or "bumps" put in cylinder ports to improve the mixture preparation in the cylinder that resulted in more power but lower CFM flow rates.

        Something else is that there can be massive differences in flow between flow benches. It's all about how they are set up....

        From the little that I've learned so far, I think putting the head on an engine is the only real indicator of the performance difference.
      1. LostMarine's Avatar
        LostMarine -
        Click here to enlarge Originally Posted by PEI330Ci Click here to enlarge
        From the little that I've learned so far, I think putting the head on an engine is the only real indicator of the performance difference.
        well, ill start an acount for people to donate to so i can get these put on Click here to enlarge
      1. BavarianBullet's Avatar
        BavarianBullet -
        Everyone seems to be assuming both vac and paw are flow testing the same port and I didnt see if vac was even using stock valves. Flowbenches are just like dynos- they vary a bit and it's the deltas that you care about. I'd also want to know the before/after combustion chamber size and what effect on compression ratio it might have.

        As pei330ci pointed out, flow numbers aren't everything. four-valve cylinder heads in particular suffer from cylinder air movement problems such that the ports need to be designed not just flow and velocity.Turbo engines in particular have backpressure and reversion concerns and if you change the flow in one direction, you're bound to change it the reverse. That's why its also very important to know what the valve event numbers are.

        Chances are these are mild to moderately ported heads with some valvework done and they will likely make more power. But without knowing and having control over the valve timing, its a bit of a crapshoot to me if they'd make much more power vs stock on something ASR or RB turbo N54s.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by BavarianBullet Click here to enlarge
        Everyone seems to be assuming both vac and paw are flow testing the same port and I didnt see if vac was even using stock valves. Flowbenches are just like dynos- they vary a bit and it's the deltas that you care about. I'd also want to know the before/after combustion chamber size and what effect on compression ratio it might have.

        As pei330ci pointed out, flow numbers aren't everything. four-valve cylinder heads in particular suffer from cylinder air movement problems such that the ports need to be designed not just flow and velocity.Turbo engines in particular have backpressure and reversion concerns and if you change the flow in one direction, you're bound to change it the reverse. That's why its also very important to know what the valve event numbers are.

        Chances are these are mild to moderately ported heads with some valvework done and they will likely make more power. But without knowing and having control over the valve timing, its a bit of a crapshoot to me if they'd make much more power vs stock on something ASR or RB turbo N54s.
        Bevy of great posts here including this one, nice work.
      1. BavarianBullet's Avatar
        BavarianBullet -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Bevy of great posts here including this one, nice work.
        Thanks Sticky.
      1. PEI330Ci's Avatar
        PEI330Ci -
        Lenny has a new secret....or secrets more accurately. Click here to enlarge
      1. fundahl's Avatar
        fundahl -
        No secrets!

        These heads need to start being moved out. Click here to enlarge
      1. 654's Avatar
        654 -
        I believe they have had their own 135i for a while. They must have been working on it to show some figures...
      1. dzenno@PTF's Avatar
        dzenno@PTF -
        Secret? Strong enough for a man but made for a woman?
      1. oddjob2021's Avatar
        oddjob2021 -
        i recently got information that PAW has a local customer who is going with their heads. the customer does not have upgraded turbos atm but i was told he's working with a turbo company and he wouldnt give me the info on them. will be interesting to see what develops.