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Thread: dynamic compression.

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    Spanner Monkey

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    dynamic compression.

    What dynamic compression is a safe number to use with 98 octane fuel on a pinto 2 litre with twin 45mm side draughts cheers Mario.

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    Re: dynamic compression.

    i would imagine air and under bonnet temps would have a dramatic effect. i would also imagine no one will give you an answer! if your DCR is on the low side your engine will be quite tolerant to timing, but if you starting to push the boundaries then your find the engine will be very sensitive to timing.
    Last edited by Graham; 22-05-2018 at 18:31.

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    Re: dynamic compression.

    hi graham

    dynamic compression at 9;1 cheers mario.

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    Re: dynamic compression.

    i remember reading a long long article on DCR many many years ago, written by vizard if i remember, the net result was all the best supercars from loads of manufacturers at the time had a DCR of 8.8:1 so the upper limit isnt going to be far away from where you are now!

    in practise although we all talk about static compression we are in actual fact making allowances for DCR which is why engine builders use around 10.1 on a fast road cam, around 11.1 on most rally cams and about 12.1 on race cams its not that clear cut but you get the idea.

    to be honest eve if someone gave you an answer, which they wont, how is it going to help you, are you really going to build an engine based around what some bloke on the internet told you?

    i know of a vauxhall xe engine which runs a staggering 15.1 cr on 98 octane. so if you said to me whats the max compression you could get away with on an xe i might answer 15.1.

    But you'd be in trouble if you tried it, because the bit of info i haven't give so far it it breathes through a tiny 19mm restrictor

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    Spanner Monkey

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    Re: dynamic compression.

    Hi graham is it fear to say the more you can fill the cylinder with air and fuel the less compression is need in the engine,
    engine builders there are using 11:1 compression with a Kent gets 2 cam and making 160 rearwheel. Hp

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