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  1. #31
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    VL heads have 1.94 & 1.6" valves - too big.
    You want HQ style red heads with no exhaust crossover port (heat riser port), doubtfull you'll find any with the correct valve sizes - best bet it to find a set with stock valve sizes that have not been butchered, are not heavily rusted in the water jacket & have minimal core shift.
    Most likely they'll need:
    Hot tank & bead blast
    Guides K-lined
    Spring seats machined for double springs
    Guide tops machined for positive seals
    Seats machined for the larger valves, chamber reliefs cut & throating cuts done - you want an exhaust seat that is radiused into the bowl
    Pocket port with cleaned up runners, a small amount of chamber reshaping to unshroud the valves
    Flow test
    CC'ed & milled for compression
    Valve tip heights checked & ground equal
    Spring installed heights checked & shimmed as required

    The advantages of E85 come from being an oxygenated fuel - it contains oxygen which is released under heat & pressure, so you can burn more of it with X amount of oxygen from the atmosphere = more power.
    It is also very detonation resistant, so you can run much higher compression & see more power gains.
    It also runs cooler, which can be important on a track car.

    All in all it's damn near a perfect race fuel but costs a lot less than anything comparable.

    For headers you want 1 5/8" primary tri-Y's, pacemaker are good, but pretty much any header that fits those specs will get the job done - don't be tempted to run 4-1's, they are great for a street/strip engine but lack midrange punch on a circuit engine.

  2. #32
    Part of the furniture Williamz's Avatar
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    Do early style heads run hotter than post EFI ones because of their siamese exhaust ports? Just asking, thanks.

  3. #33
    Do you ever leave? HQ308Ute's Avatar
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    one little thing i'll throw in with the catch can as well is that those oily fumes the can is catching actually lower your air/fuel mixture octane a few points.. considering we're all grasping for as much octane as possible its a good idea to run a can in any case.

  4. #34
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    Quote Originally Posted by TK383 View Post
    VL heads have 1.94 & 1.6" valves - too big.
    You want HQ style red heads with no exhaust crossover port (heat riser port), doubtfull you'll find any with the correct valve sizes - best bet it to find a set with stock valve sizes that have not been butchered, are not heavily rusted in the water jacket & have minimal core shift.
    Most likely they'll need:
    Hot tank & bead blast
    Guides K-lined
    Spring seats machined for double springs
    Guide tops machined for positive seals
    Seats machined for the larger valves, chamber reliefs cut & throating cuts done - you want an exhaust seat that is radiused into the bowl
    Pocket port with cleaned up runners, a small amount of chamber reshaping to unshroud the valves
    Flow test
    CC'ed & milled for compression
    Valve tip heights checked & ground equal
    Spring installed heights checked & shimmed as required

    The advantages of E85 come from being an oxygenated fuel - it contains oxygen which is released under heat & pressure, so you can burn more of it with X amount of oxygen from the atmosphere = more power.
    It is also very detonation resistant, so you can run much higher compression & see more power gains.
    It also runs cooler, which can be important on a track car.

    All in all it's damn near a perfect race fuel but costs a lot less than anything comparable.

    For headers you want 1 5/8" primary tri-Y's, pacemaker are good, but pretty much any header that fits those specs will get the job done - don't be tempted to run 4-1's, they are great for a street/strip engine but lack midrange punch on a circuit engine.
    Thanks for the info TK, Very helpful! If i want to keep the car Road worthy will i run into troubles with using these heads. Not 100% sure yet but may be a possibility that i keep it on the road.

    How much would i be looking at to get that work done to the heads? The E85 option ill have a think about, sounds like a good idea!

    Ill keep an eye out on ebay etc for some 1 5/8 headers, currently have the efi tri Y's so ill look out for another set for early heads.

    Once again thanks for your help.

  5. #35
    been here .......too long Smitty2's Avatar
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    Quote Originally Posted by Williamz View Post
    Do early style heads run hotter than post EFI ones because of their siamese exhaust ports? Just asking, thanks.
    no...
    but BOTH styles suffer from the rear of head hotspot problem (that blows head gaskets and causes overheating cooling issues)

    the solution for both is the HDT kit or a make your own..so coolant can circulate at the back of the engine
    like this




    and thats the starter coddled in heatwrap at the bottom of the engine...as the exhaust heat kills them
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  6. #36
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    smitty, have you just drilled a hole in the intake at both the rear water jackets and tapped it then added to barb fittings so to speak? also where are you running them to? just the two outlets on the waterpump? also is this a good idea for a everyday driver aswell as a race car? cheers ryan

  7. #37
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    If you already have the injected heads and extractors stay with them.

  8. #38
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    Quote Originally Posted by kiwiwalkinshaw View Post
    If you already have the injected heads and extractors stay with them.
    Thats what my original plans were as i do have them, just was looking for a manifold and cam to suit but have been advised that early heads are the better choice.

  9. #39
    been here .......too long Smitty2's Avatar
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    Quote Originally Posted by ryan350 View Post
    smitty, have you just drilled a hole in the intake at both the rear water jackets and tapped it then added to barb fittings so to speak? also where are you running them to? just the two outlets on the waterpump? also is this a good idea for a everyday driver aswell as a race car? cheers ryan
    spot on mate.... (and saves having to tap and plug the heater outlets on the water pump on the race car )
    as something to do on your daily?...cant really comment but probably a waste of time (and where do you hook up the heater hoses..unless you get the HDT kit)
    plus
    really I dont think its needed as you would not have the engine running at WOT at very high temps on a streeter (unless its Sat night on the industrial estate...if you get my drift )
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  10. #40
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    haha i hear you loud and clear mate! thanks

  11. #41
    Part of the furniture matty12's Avatar
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    Smitty, with the hoses set up on the water pump is that pulling hot water from the heads back into the inlet of the engine?? Would it be better but also harder to run it to the thermostat housing so the hot water can then be cooled by the radiator. I just remeber seeing speedway cars that run four hoses from either corner of the inlet manifold to four fittings on the inlet to the radiator.

  12. #42
    been here .......too long Smitty2's Avatar
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    Quote Originally Posted by matty12 View Post
    Smitty, with the hoses set up on the water pump is that pulling hot water from the heads back into the inlet of the engine?? Would it be better but also harder to run it to the thermostat housing so the hot water can then be cooled by the radiator. I just remeber seeing speedway cars that run four hoses from either corner of the inlet manifold to four fittings on the inlet to the radiator.
    I am not an expert on this...but after losing a lot of head gaskets in the first 2-3 years of trackwork, I went chasing solutions (as headgaskets swaps after every event is a PITA)
    and I found out about the HDT solution ...developed by Larry Perkins which uses a hollow manifold bolt and hooks the rear head coolant into the heater cooling circuit via a thin hose.
    (Rare Spares sell them)

    The whole idea is to remove the hotspot in the rear of the heads...as coolant gets there, does not circulate, gets superheated and turns to steam...and blows the head gasket away!

    like this...


    Problem was..on a race car you dont have the heater hooked up (in fact most remove the whole HVAC unit for weigh saving) so how...?????
    I wanted it simple so I went with hoses hooked up to the water pump coz i knew the coolant would circulate (and eventually go thru the radiator)
    and
    since doing that mod..NO head gaskets have been lost! guess it works. And since doing my mod I have seen other variations ...like from the rear
    to a fitting inserted on the top radiator hoses..or to the thermostat housing. All swear they work (probably coz the coolant does move)


    hth
    Last edited by Smitty2; 09-03-2012 at 12:21 PM.
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  13. #43
    Part of the furniture Williamz's Avatar
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    [QUOTE=Smitty2;492944]no...
    but BOTH styles suffer from the rear of head hotspot problem (that blows head gaskets and causes overheating cooling issues)

    the solution for both is the HDT kit or a make your own..so coolant can circulate at the back of the engine
    like this

    Thankyou mate Certainly things to consider in the near future
    Torque is how many horses you have. Power is how fast they can run.

  14. #44
    Do you ever leave? immortality's Avatar
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    Quote Originally Posted by Smitty2 View Post
    since doing that mod..NO head gaskets have been lost! guess it works. And since doing my mod I have seen other variations ...like from the rear
    to a fitting inserted on the top radiator hoses..or to the thermostat housing. All swear they work (probably coz the coolant does move)

    hth
    I think you've nailed it in the last sentence, because the coolant is moving. That is exactly what some cooling system guy told me a few years ago, keep the coolant moving and prevent local hot spots which will cause the coolant to boil and create air pockets leading to blown gaskets (exactly as you have shown). Good to see it really does work. Those guys at HDT didn't miss much.

    When I get my new manifold it will definitely be modified to suit

    something else I spotted in a pic of the engine bay of the last of the "big banger" HDT Commodores, it looked like they had some sort of swirl pot plumbed into the top coolant hose going from the radiator to thermostat housing. Any body have any idea what that was for?

  15. #45
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    Quote Originally Posted by immortality View Post
    something else I spotted in a pic of the engine bay of the last of the "big banger" HDT Commodores, it looked like they had some sort of swirl pot plumbed into the top coolant hose going from the radiator to thermostat housing. Any body have any idea what that was for?
    Are you talking about a little black cylinder with a lid on top plumbed into the top radiator hose? (cant see the pic) If so, it's a filter.

    Tefba Radiator Filter
    Last edited by Bill355; 09-03-2012 at 03:01 PM.

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