Modified 8v project head

Discussion in '8-valve' started by mr hillclimber, Nov 5, 2007.

  1. Tristan Forum Junkie

    Joined:
    Apr 25, 2006
    Likes Received:
    270
    Location:
    Southern IRELAND
    Well my tame local engine tuner deals with REC , and is to ring Paul today or tomorrow . He felt the exhausts are restrictive , when you consider the sharp Short Side Radius , even with porting , it will help the engine breath out . I need to change my guides and valves anyway , so I'm gonna go for the 40/35 combo . With either carbs or TBs , newman fast road cam ,mild skim of head to keep the compression high , and I've a nice 4-2-1 Ex mani. Probably lose the dizzy for either an Omex or DTA ignition too. I'll be hoping for a nice torquey 135-140 bhp .
     
  2. mr hillclimber Club GTI Supporter and Sponsor

    Joined:
    Nov 24, 2005
    Likes Received:
    131
    Location:
    Southwest
    I cant remember what size yours is.. 1800 or 2tlr ?

    A 40mm inlet will be ok on either for a torquey road engine, but for the money, I'd still go up 1mm on the inlet for best performance, esspecially on open induction.

    You should have no problem "at all" exeeding those figures.
     
  3. Tristan Forum Junkie

    Joined:
    Apr 25, 2006
    Likes Received:
    270
    Location:
    Southern IRELAND
    1.8 base Gti block/head with a 1.0mm overbore , lightened balanced crank , flywheel , and rods.
     
  4. mr hillclimber Club GTI Supporter and Sponsor

    Joined:
    Nov 24, 2005
    Likes Received:
    131
    Location:
    Southwest
    1825cc then. Should be good for around 155hp with the 40mm inlet and the right bits.
     
  5. jamesa Forum Junkie

    Joined:
    Nov 8, 2003
    Likes Received:
    301
    Location:
    Abz
    My `old` 1800 produced 140bhp with:

    Solid lifter TSR Pack D head - 40mm in. / 35mm ex.
    285` cam
    Kjet plus KStar (KS301)

    [​IMG]
     
    Last edited by a moderator: Jan 23, 2018
  6. Tristan Forum Junkie

    Joined:
    Apr 25, 2006
    Likes Received:
    270
    Location:
    Southern IRELAND
    interesting graph.... wonder what caused the Spike at 4400?
     
  7. jc.. Forum Member

    Joined:
    Oct 22, 2003
    Likes Received:
    0
    Location:
    Virgin Islands
    105 whp is 140bhp? 33.3%? isn't that a generous figure for 2wd
     
  8. Jon Olds Forum Junkie

    Joined:
    Jan 28, 2004
    Likes Received:
    371
    Location:
    United Kingdom
    seems 'cammy' for a 285. What was the O2 doing?
     
  9. Tristan Forum Junkie

    Joined:
    Apr 25, 2006
    Likes Received:
    270
    Location:
    Southern IRELAND
    I was on to Mr Paul Ivey today , lovely man... He only lists 42 mm In and 35 mm Ex for a solid lifter head , Ex's being 13.30 each . He has 40s and 35s for Hyd heads though . And he doesn't do guides anymore , his machine is broken , nor does he do seat inserts .
     
  10. mr hillclimber Club GTI Supporter and Sponsor

    Joined:
    Nov 24, 2005
    Likes Received:
    131
    Location:
    Southwest
    Yeah a proper old school gent.

    Thats a good price, I need some replacement exhausts.. dont suppose he said if they came with single, or the standard tripple collet grooves.. or 7 or 8mm stems ?
     
  11. Jon Olds Forum Junkie

    Joined:
    Jan 28, 2004
    Likes Received:
    371
    Location:
    United Kingdom
    nice job
     
  12. Tristan Forum Junkie

    Joined:
    Apr 25, 2006
    Likes Received:
    270
    Location:
    Southern IRELAND
    Triple collet grooves , 8mm stem . I had hoped for 7mm....but then it is only road use so won't make a lot of difference . Who does nice bronze guides? And will replacement ones be a fit without machining job , I wonder.....
     
  13. mr hillclimber Club GTI Supporter and Sponsor

    Joined:
    Nov 24, 2005
    Likes Received:
    131
    Location:
    Southwest
    Arrow do valve guides... http://www.arrowprecision.co.uk/... though no listings on line so a phone call would be needed.

    Failing that, 8mm is the standard size so genuine or an engine reconditioners, or GSF. I paid about 1.40 a guide for the project head from GSF, though my machinist said they do two different types, the ones I had that came in a plastic bag (which he said were ok-ish, though he is a fussy bugger) and apparently another type that come in a hard plastic case, which are allegedly better... worth asking I spose.

    All guides should be fitted by a pro so the clearance can be checked after against the valves being used.

    As for the 7mm stems.. it's all in the details.. 7's are better but if your not chasing the last couple of hp the standard size will be ok.

    You dont have to use valves listed for VW, but it's a lot of grief to have the head's of a thin stem valve turned down, then find alternative collets if the grooves are different etc.
     
    Last edited: Jan 24, 2008
  14. mr hillclimber Club GTI Supporter and Sponsor

    Joined:
    Nov 24, 2005
    Likes Received:
    131
    Location:
    Southwest
    Small update...

    After discussing the design of the exhaust on the project MK2, we came to the obvious conclusion, that the baffle plate which the exhaust gases had to go around to exit the twin tailpipes from the single inlet, was'nt exactly the best idea from Magnex for good flow.

    As my friend had to re-pack the exhaust a couple of years ago, it already had an access plate in the box. He removed the plate and modded the perforated tubing along the lines of the Supersprint systems as we discussed.

    With the silencer re-packed, the difference is immediately obvious. My friend claims a "seat of the pants" feel of between 5-10hp gain, better throttle responce and freer reving.

    [​IMG]

    The moral.. dont always presume a "performance" exhaust is designed with performance in mind.

    A recent motorway round trip resulting in 300 miles on 3/4's of a tank, and comments of "it "kin flies between 80-110" (kmh obviously officer!) from someone who regularly rides a 600 Bandit, seems to be proving the worth of the conversion. We've still yet to swing the cam timing and optimise the fueling.

    The bug has now bitten, the factory soundproofing from under the carpet has gone, the tow bar is following soon... moddified cars eh..
     
  15. Jon Olds Forum Junkie

    Joined:
    Jan 28, 2004
    Likes Received:
    371
    Location:
    United Kingdom
    Ashley

    To re-inforce this, I bought the Ashley 16V mk1 manifold and
    had a look up it from the outlet. It had overlapping pipes and was generally
    not a good shape.
    Chopped it up with a hacksaw, "gas flowed" it (got rid of the obvious shape mismatches) and re-elded it together. Job done. It still had a poor shape around cyl 1 near the manifold though.
    It all counts. From the bellmouth to the tailpipe, don't think of the head in isolation.
     
  16. jamesa Forum Junkie

    Joined:
    Nov 8, 2003
    Likes Received:
    301
    Location:
    Abz
    Not sure ... the KStar altering the fueling perhaps ?

    Hopefully ... :)

    TSR 103 cam ~ 11mm lift, O2 not measured AFAIK
     
  17. Jon Olds Forum Junkie

    Joined:
    Jan 28, 2004
    Likes Received:
    371
    Location:
    United Kingdom
    lambda

    If the mixture was doing something stange as it came on cam it may exacerbate the curve shape.
     
  18. jamesa Forum Junkie

    Joined:
    Nov 8, 2003
    Likes Received:
    301
    Location:
    Abz
    No lambda fitted.

    The KStar uses it`s own injector .. connected to the WUR to reduce the fuel pressure in accordance with the ignition curve (vac. connection at dizzy is blanked off). Vac. connection runs to the KStar module.
     
  19. A.N. Other Banned after significant club disruption Dec 5th 2

    Joined:
    Oct 23, 2003
    Likes Received:
    395
    Found a Dave Walker article on 8-valve race heads from the Golf, April 2001

    Scan here
     
  20. A.N. Other Banned after significant club disruption Dec 5th 2

    Joined:
    Oct 23, 2003
    Likes Received:
    395

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice