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Old 10-15-2004, 09:39 AM
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Default Valve question

I have a set of Ferra 2.02/1.57 valves and I put them all in a line on a flat surface as well as put a straight edge across them and visable to the eye they are different heights. Is this a normal thing being different heights, and will this be a problem when installed. When I say different heights I mean where the valve stem is cut for the retainer as well as tip of stem....


Thanks for your input.
Old 10-15-2004, 10:31 AM
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I have heard of this but I would like to know more.
Some of the wormanship today is just plain ****. Can't understand how this can happen in a quality controlled environment.
Old 10-15-2004, 10:57 AM
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The margin of the valve can very depending on what the mfg's +/-'s are. To measure the length though, you need to measure from the top of the keeper groove to the botton of the seat angle. Margin thickness will not effect installed height, just CC volume. Of course it will affect airflow also...

Chris
Old 10-15-2004, 11:07 AM
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Installed on the head you can see that the springs are different heights as well. You can see a difference in height no matter which way you look at them... Wouldnt that cause seat pressure to change? Could it weaken a spring faster not being installed at the recommended height? Valve float?? Geometry to be off? What if I threw .050 more preload into the equasion? Like say .090 preload on a stock lifter and stock rockers with an XE lobe cam and Rev. Dual 1116 springs (none broken).

Car has a loud tick from the drivers side head, and car pops out the exhaust as well as idles like ****. Motor will shake and smooth out for a second then shake and it shakes the whole car....

No Missfires, but there is knock at WOT... leak down test, injectors tested...all good.

?????????????????????????????
Old 10-15-2004, 12:23 PM
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All things being equal, that must affect the spring installed height and the springs on the short valve will be more compressed.
If you did other mods at the same time that may be causing the poor running, but perhaps if the lifter can't take up the lash there is a problem with flow.
I imagine that the lack of adjustment in the stock rockers will mean that you can't take up any lash that may be generated by the lower installed height.
I have one valve that looks to have a slightly lower installed height but I plan on using my adjustable rockers with them.
I would like to hear from others that have had to deal with this.
Old 10-15-2004, 12:30 PM
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OK. well the car ran good for 3 months, came out over the winter and had this problem... nothing was changed... car dropped .4 and 4mph as well as runs bad and pops out the exhaust @ 2500 - 3000k rpms... with a 224 cam. Pop isnt a timed pop (like every half a second) its a spuratic pop, but continuously. Stock rocker arms were twisting in their seats as not shifting from side to side... twisting. Tip of valve stem was covered by half of tip of rocker... all were shifted, some worse than others...????

Last edited by CRAWLIN; 10-15-2004 at 12:36 PM.
Old 10-15-2004, 12:40 PM
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So I presume the original Q was 'retro' and you noticed this whe you first put the valves in.
Were they after-market heads?
Don't really know why you lost time after winter but twisting rockers has to mean the geometry was off.
There must be some other folks that can advise....
Old 10-15-2004, 12:45 PM
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I had the problem and started looking into the problem... pulled the valves out of the head to inspect and yes they are modified heads 2.02/1.57 ferra valves. I did measure from the deck to the valve cover seat on both heads and came up with .010 difference between the 2 heads... Smaller head being the one that i hear noise from... What can throw off the geometry???
Old 10-15-2004, 12:49 PM
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The car had 7.400 pushrods and was supposed to have 7.350's. Car had .090 preload and the heads are 58-59cc chambers with .030 milled. Alls I know is I had a different set of modified heads on the car and these were put on and the other ones lasted a year then swapped for these and less than a year i have nothing but problems and i cant seem to find the problem yet...
Old 10-15-2004, 01:50 PM
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Just wondering whether new guides and seats were fitted incorrectly??? That would throw off the alignment. Check the spacing of the valve tips to see if they are even/correct.
What cam are you running?
Just can't think what would change in 4 months laid up.
No P2V damage (milled heads)?
Old 10-15-2004, 02:10 PM
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New heads done by a company, installed by a shop with specs stated above. Running a 224 cam with heads milled .030 and they cc'd @ 58-59 cc. No visable P2V issues.

I will have to check the spacing of the valve tips...

Someone has to have some insite on this matter????? Anybody????
Old 10-16-2004, 11:05 AM
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Anyone




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