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    • N54 cylinder head tech by VTT - Flow, intake valves, exhaust valves, porting, Schrick cams, and N53 head comparison

      The N54 head is not BMW's best work. Why? It did not need to be to hit their goals. People forget this is not an M motor and BMW did not create a high revver or top end monster with the N54. The good part of that is you can pick up nice gains on the N54 head in the aftermarket.


      VTT goes into some of these details in their technical article regarding the N54 head. Read it below.



      This article was originally published in forum thread: VTT Tech Article: Head Flow started by Chris@VargasTurboTech View original post
      Comments 11 Comments
      1. 93siro's Avatar
        93siro -
        Good stuff. What is needed to use N53 head on N54 block?
      1. Chris@VargasTurboTech's Avatar
        Chris@VargasTurboTech -
        Click here to enlarge Originally Posted by 93siro Click here to enlarge
        Good stuff. What is needed to use N53 head on N54 block?
        There are a bunch of things needed, among them:
        Coolant passages are different
        Head bolts are 1 mm smaller
        On the exhaust side it's the same bolt pattern but larger ID on the ports and OD for the gaskets which means you're going to need custom exhaust manifolds or do other trickery.

        It's a high flowing head -flows way better than the N54, obviously- but you have to be willing to do custom work, or pay someone else to do it for you to just be able to bolt 'er on. For some it may be worth it, but for most I think just doing a nice PNP on a N54, maybe even add a cam and you'll see plenty of real world gains with zero fitment issues.

        We were asked by a couple guys "what about a stock N53 head, how does that flow?" We have no idea, and in our opinion that's not a great option for cost savings as you still have to do all the other things to make 'er fit on an N54... if you're gonna do it, while you're in there may as well PNP too!

        Chris
      1. maxnix's Avatar
        maxnix -
        So to summarize, if you are not going for trophy numbers, for a N54 built block, modify the N54 head?

        Is it worth even thinking about a PNP N54 head on a stock N54 block with stock internals? For street only, perhaps?

        It seems at upper rpm the N54 head with its simpler intake valvetrain has an advantage over the S/N55 heads and maybe also over the B/S58 heads?
      1. Torgus's Avatar
        Torgus -
        Click here to enlarge Originally Posted by maxnix Click here to enlarge
        Is it worth even thinking about a PNP N54 head on a stock N54 block with stock internals? For street only, perhaps?
        Only if you can't hit your desired hp #s with your turbo(s) and fuel. I mean you can make more HP than the stock block can take with an off the shelf turbo kit. From that perspective, no need to work the head etc.

        I personally do not see why you would want to build a head and add cams on a stock block unless you were running small turbo(s) for spool reasons or because of a class restriction.

        The bang for your buck is not there on stock turbos unless you wanted to take the stock turbo world record. Which would be comical. I am surprised VTT has not done that yet, even if just for $#@!s and giggles. Weld the wastegates shut and #sendit

        A fully built head is like what 3k+? add another 1k for cams. 4k uninstalled is pricey unless you are chasing records.
      1. JBacon335's Avatar
        JBacon335 -
        Would be nice when trying to make as much as possible on pump gas since you won't have to run as much boost to make the power
      1. Sticky2's Avatar
        Sticky2 -
        Click here to enlarge Originally Posted by JBacon335 Click here to enlarge
        Would be nice when trying to make as much as possible on pump gas since you won't have to run as much boost to make the power
        This exactly and pump gas power is way too overlooked on the platform.
      1. langsbr's Avatar
        langsbr -
        I wouldn't say overlooked, but rather that the value in this platform is only truly realized with ethanol.
      1. Torgus's Avatar
        Torgus -
        Click here to enlarge Originally Posted by JBacon335 Click here to enlarge
        Would be nice when trying to make as much as possible on pump gas since you won't have to run as much boost to make the power
        yeah, at the cost of a single turbo upgrade...I am not saying it is not worth it, but on most cars the money could be better spent elsewhere in most cases.
      1. JBacon335's Avatar
        JBacon335 -
        It would be equally beneficial on a single turbo setup as it is on a twin setup. Maybe even more so. Not everyone has access to ethanol, and race gas ain't exactly cheap
      1. Torgus's Avatar
        Torgus -
        Click here to enlarge Originally Posted by JBacon335 Click here to enlarge
        It would be equally beneficial on a single turbo setup as it is on a twin setup. Maybe even more so. Not everyone has access to ethanol, and race gas ain't exactly cheap
        I agree 100%, that is me in a nut shell, zero E85 is available. Which is one of the reasons I have a single turbo. Twins just blow too much hot air imo.

        There is nothing wrong with a fully worked head and cams, there are obvious gains. $3800 head + $1,500 cams = $5,300 + install.
      1. AWSAWS's Avatar
        AWSAWS -
        It's a really nice upgrade. I'd love to do it but I won't be able to justify the cost.
        I already have GC turbos and I often run them at 21 psi on the street. Sometimes up to 25 psi.
        I have run 27 psi a couple of times but at the time that was about the limits of my fuel supply.

        They can probably do 30 psi but I feel like that's in a bit of a danger territory with the car. Detonation, cracked cylinder liners. Head lift. Plus on a stock drivetrain I worry that parts there will not last long.

        It would be really nice doing big power on regular pump gas though.