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    ht1 vs ht1e

    anyone had experiences with the ht1 vs ht1e , i'm getting different views of information some saying its not as good for power as the older HT1 and that the HT1e power drops off earlier , why would that happen ? as the HT1e is meant to be a newer and advertised better cam

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    Re: ht1 vs ht1e

    Quote Originally Posted by JefferySnow View Post
    anyone had experiences with the ht1 vs ht1e , i'm getting different views of information some saying its not as good for power as the older HT1 and that the HT1e power drops off earlier , why would that happen ? as the HT1e is meant to be a newer and advertised better cam
    There’s some info here on a thread I started as my big valve head came with a ht1e, I’ve not done anything with it yet tho.

    http://www.turbosport.co.uk/showthre...931&highlight=

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    Re: ht1 vs ht1e

    Thanks Warrior for the link , very interesting . from what I can gather the HT1 seems to work better that a HT1e with the correct bottom end spec . Im still trying to get my head around how the HT1 is a cam that can give power of over 200bhp when the lift it gives is less that 12.5mm I though cams over 13mm give the power

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    Re: ht1 vs ht1e

    Quote Originally Posted by JefferySnow View Post
    Thanks Warrior for the link , very interesting . from what I can gather the HT1 seems to work better that a HT1e with the correct bottom end spec . Im still trying to get my head around how the HT1 is a cam that can give power of over 200bhp when the lift it gives is less that 12.5mm I though cams over 13mm give the power
    I am fair from an expert on this, all I know is what people have told me on here and from reading,

    I have seen a lot the the advertised specs of a newer cam are not always correct and that they are there to sell the cam,

    also the compression and correct bottom end as you mentioned,

    theres assorts of variants, electronic ignition vs dizzy, fuel injection vs carbs etc,

    difference in big valve heads, graham has done a lot of development with pinto heads, just slapping some big valves in is useless without the correct porting,

    the only way you would truly know would be to degree and measure both new and old cams or do back to back test on a rolling road or similar.

    graham will be able to shed a lot more light on this than me,

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    Re: ht1 vs ht1e

    Sadly I never had a HT1 camshaft in and never measured the real profile (do have the HT1e profile). On internet, I get confusing info. One day I have to believe this cam is faster build up as the HT1e, next time other info seems to send me in the opposite direction, letting me believe it is less aggressive. I'm almost sure this is the case.

    First of all, if you can find a super cylinder head, HT1e is probably the fastest cam which can make and power and torque. But I've not seen these heads yet. With Super head I mean a cylinder head which can make easy 200 bhp. Let say 210 - 220. Piper A8 is a better option if you can't make 200 Bhp but get stuck just as I did round +/- 190 Bhp (because of the head, not cam).

    I'm currently working on a compromise A8. One who can make the same power as A8 but more torque. And probably a second, one step up but not as much lift at TDC as the HT1e.
    Last edited by onyd; 12-03-2018 at 17:53.

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    Re: ht1 vs ht1e

    Quote Originally Posted by JefferySnow View Post
    Thanks Warrior for the link , very interesting . from what I can gather the HT1 seems to work better that a HT1e with the correct bottom end spec . Im still trying to get my head around how the HT1 is a cam that can give power of over 200bhp when the lift it gives is less that 12.5mm I though cams over 13mm give the power
    depends on the head, if max airflow is at 12.5mm or less, lift then lifting higher will not gain you any more unless you also get more duration. most heads the airflow difference between 11.5mm lift and 13mm is actually quite small, if you ask dave walker he will say you really only need to lift to 12mm to get real power, well actually he says 480 thou, which is near as dam it 12mm

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    Re: ht1 vs ht1e

    Quote Originally Posted by Graham View Post
    depends on the head, if max airflow is at 12.5mm or less, lift then lifting higher will not gain you any more unless you also get more duration. most heads the airflow difference between 11.5mm lift and 13mm is actually quite small, if you ask dave walker he will say you really only need to lift to 12mm to get real power, well actually he says 480 thou, which is near as dam it 12mm
    If you look at the overall valve lift of the Newman cams, most of them are only around 470 thou lift. Are some of these cams the old Emerald ones which were designed by Dave Walker? If so it bears out what you are saying Graham.

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    Re: ht1 vs ht1e

    Quote Originally Posted by Forest_rallying View Post
    If you look at the overall valve lift of the Newman cams, most of them are only around 470 thou lift. Are some of these cams the old Emerald ones which were designed by Dave Walker? If so it bears out what you are saying Graham.
    correct, although even then the cams were based on old holbay profiles

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    Re: ht1 vs ht1e

    Most cams hanging around are Holbay copies very often made in different in and exhaust combinations. If you start measuring Piper, Kent and Newman cams, they all come very close to each other.

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    Re: ht1 vs ht1e

    Onyd have you ever experienced a Kent gts4 vs an A8 piper ? The gts4 is a similar grind to a holbay cam

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    Re: ht1 vs ht1e

    No, never had it in You may always send me the cam, I'll measured ad send back.

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    Re: ht1 vs ht1e

    Quote Originally Posted by JefferySnow View Post
    Onyd have you ever experienced a Kent gts4 vs an A8 piper ? The gts4 is a similar grind to a holbay cam
    The Kent GTS4 is a copy of the Old Holbay 4011 FHL.

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    Re: ht1 vs ht1e

    That must be why the gts4 gives big bhp figures in a good flowing head .. Holbay were the daddys back in the day

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