Oh wise one you ask all the right questions it looks like the head fell off the valve first so the cam was the egg.Now you look at the pics and till me how I came to that?classicdat wrote:Oh Wow, don't think that will buff out. Was the cam the chicken or the Egg?
O shit this is what happins when you get to clever
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gman
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Re: O shit this is what happins when you get to clever
Last edited by gman on Sat Apr 16, 2016 9:48 pm, edited 1 time in total.
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Bartman
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Re: O shit this is what happins when you get to clever
Ohh that's nasty!
They don't call me the man with the rubber arm for nothing you know.............
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volodkovich
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Re: O shit this is what happins when you get to clever
What is the cam profile and what were your open & closed spring loads? I'd be happy to look into this a bit for you as I have never seen an L smash a cam to bits like this! Could be a harmonic issue.. Ramp acceleration doesn't change spring requirement much, it is more the negative acceleration over the nose that does. High opening acceleration however does tend to increase the Fourier content of the profile which can excite valve springs in a bad way.gman wrote:No the spring rate had to be so high because the ramp on the cam is so harsh.So looks like I am going to have to make a chromoly cam?broke wrote:Did you remove and refit the cam towers?
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gman
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Re: O shit this is what happins when you get to clever
Thanks Man I had to go up 10% on the springs last rebuild because I was getting sign of spring flutter and it looks like it pulled the head off the valve and the pistons have come up and hit the valves and that's broken the cam.volodkovich wrote:What is the cam profile and what were your open & closed spring loads? I'd be happy to look into this a bit for you as I have never seen an L smash a cam to bits like this! Could be a harmonic issue.. Ramp acceleration doesn't change spring requirement much, it is more the negative acceleration over the nose that does. High opening acceleration however does tend to increase the Fourier content of the profile which can excite valve springs in a bad way.gman wrote:No the spring rate had to be so high because the ramp on the cam is so harsh.So looks like I am going to have to make a chromoly cam?broke wrote:Did you remove and refit the cam towers?
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gingofthesouth
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Re: O shit this is what happins when you get to clever
So basically this is what I heard in my head when I read this!volodkovich wrote:What is the cam profile and what were your open & closed spring loads? I'd be happy to look into this a bit for you as I have never seen an L smash a cam to bits like this! Could be a harmonic issue.. Ramp acceleration doesn't change spring requirement much, it is more the negative acceleration over the nose that does. High opening acceleration however does tend to increase the Fourier content of the profile which can excite valve springs in a bad way.gman wrote:No the spring rate had to be so high because the ramp on the cam is so harsh.So looks like I am going to have to make a chromoly cam?broke wrote:Did you remove and refit the cam towers?
https://www.youtube.com/watch?v=vHk40Vv ... tu.be&t=59" onclick="window.open(this.href);return false;
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datsunboy
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Haha that video is awesome
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1970 Datsun 1600 - CA18DET - Sold!
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240znz
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Re: O shit this is what happins when you get to clever
Only one word required.
Bugger!
Bugger!
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kobyn
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O shit this is what happins when you get to clever
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Bartman
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Re: O shit this is what happins when you get to clever
Do you have a replacement cylinder head? I know where there's an.old l26 that might have a good head.
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gman
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Re: O shit this is what happins when you get to clever
Thanks Bart always looking for heads. well now its time to work out what to do I think I will get the little women a new handbag and me some more HP?Bartman wrote:Do you have a replacement cylinder head? I know where there's an.old l26 that might have a good head.