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Redblock head porting

A member inquired about porting and I figured I may as well share it with everyone. I've also got a 530 head kicking around that someone else ported that I will try and motivate myself to post pictures up of. When I do my 16 valve head I'll add that to this.


Way back in 2008, I more of less just followed what I saw in pictures on turbobricks and elsewhere online when I ported my 405 head which is more or less the same as a 351.

This is what I started with, some of the worst scum build up I've ever seen, came from a low km car that was probably driven to gently.

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Valve stems are removed in the pics because I replaced them while i was at it. Some people cut/grind the valve stems short so they don't protrude into the intake port. Increased flow, likely reduced longevity of valve stems as a result but may well not be significant.

Bigger 38mm exhaust valves were installed and the combustion chamber opened up around them. The extents of how far it could be opened up were found by overlaying a headgasket and marking around the fire ring leaving a mm or so buffer. Was planning on going turbo at the time. I wouldn't bother doing it if I did it again now.

Both the combustion chamber and the exhaust port were done to a polished finish. Intake was a slightly rough finish which is meant to be better for fuel atomisation. Intake ports and the intake manifold were gasket matched. This is done by overlaying the intake gasket, marking the edges of the gasket, and porting up to that line.

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It was all done with a dremel and a die grinder using sanding drums and sanding flap bits. Grinding stones don't work because they get clogged with aluminium shavings. Where you need to take lots of material off a carbide bit can be used.

See following random pics of tools gleaned from the interwebs.

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I have head the head off again since porting and it all looked good, the smoother ports seam to really help stop scum building up on them.




Vee_QueKlaptrap24RamrodfunkDauntlessbgpzfm142

Comments

  • Bigger 38mm exhaust valves were installed and the combustion chamber opened up around them. The extents of how far it could be opened up were found by overlaying a headgasket and marking around the fire ring leaving a mm or so buffer. Was planning on going turbo at the time. I wouldn't bother doing it if I did it again now.

    You wouldn't bother with 38mm valves and porting again? Too much work not enough gain?
  • Maybe I would have seen gains if I got round to turboing it but poor value for money/effort in my mind. Between the valves and getting the seats cut to suit it cost a couple hundred. On the other hand general DIY porting costs very little other than time.
  • Vee_QueVee_Que (@Vee_Que) South Eastern suburbs Melbourne.
    Wouldn't enlarge the combustion chamber.
  • RamrodfunkRabbitt (@Ramrodfunk) Ryde,Sydney
    edited May 9
    Found this on Instagram. 8 valve racing in Sweden. Couldn't read the Swedish blurb but if someone could this looks like some insane headwork.Could be billett head,maybe.2woz88v4268s.jpeg
    Dauntlessnugget_940
  • jamesincJames (@jamesinc) Oz Volvo Ice Fortress
    @Ramrodfunk that's definitely a billet head, the chamber is totally different (plus it's covered in machining marks). I've heard there are some truly insane heads available but they cost like $10k or more.
  • This might be the head that was advertised on turbobricks Facebook a little back. Full CNC head
  • GT_PaulGT_Paul (@GT_Paul) Devonport Tasmania
    Some of my work
    i4izslyjej5a.jpg
    e2db24yquw83.jpg
    x6lujm128kc0.jpg
    hg3timviycvu.jpg
    Dauntless
  • GT_PaulGT_Paul (@GT_Paul) Devonport Tasmania

    reliefs
    tr4vvkgi2oc0.jpg
    jamesincbgpzfm142Dauntless
  • jamesincJames (@jamesinc) Oz Volvo Ice Fortress
    edited May 9
    Here's a couple photos from my first attempt last year. I got a good tip to not clean the ports too much beforehand as the carbon makes for a nice way to see which areas you've not touched yet. I scribed port throats from gaskets and went from there. I didn't modify the chambers other than to deburr sharp edges as I read that sharp edges can encourage pre-detonation due to the pressure fronts that occur around them.

    2djab3x7irql.jpg

    6r7hkl5gm5e1.jpg

    Dauntlessbgpzfm142
  • I've been following the build of that billet head - pretty interesting. The car was making 1300hp on methanol prior to the billet head. Now has 40/44mm valves and obviously different port angles. An awesome exercise in the extreme!

    efki9lypvkp2.jpg

    zhngyabxw9sr.jpg

    Dauntlessnugget_940
  • edited May 10
    I've been following the build of that billet head - pretty interesting. The car was making 1300hp on methanol prior to the billet head. Now has 40/44mm valves and obviously different port angles. An awesome exercise in the extreme!

    efki9lypvkp2.jpg

    zhngyabxw9sr.jpg

    :open_mouth:

    I wonder what they've done to strengthen the block
  • It's not an original block

    It's been designed to be stronger and you can buy the same block from Sweden
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