I need to figure out how to determine what size valve springs I need? They're Isky Tool Room springs that are most likely 1.950 or 2.00 installed height but I've been told you can't measure them on the head without a special tool. Any ideas?

I'd think you could make a good measurement with a dial caliper.

Use a really good machinist scale
I have been doing it this way for years
Bobby Layne

https://www.goodson.com/VST-60G-Anal...Spring-Tester/ The engine builders use something like this, one of the lesser expensive tools in their shop. They also make a small hydraulic portable unit that is used to check springs in the engine but it is much less accurate. Valve spring pressure is a critical element in engine design but unfortunately the optimum pressure is a trial and error endeavor. Goodson is the go to place for engine building equipment, check out their catalog and you can begin to appreciate the cost in building a racing engine.

Honest Dad himself

https://www.goodson.com/search.php?m...keep_https=yes A guy Could make himself a mechanical stop or plug to limit the travel of his machinist vice for repeat ability and use one of these little scales in a low production (back yard) environment, still lacking a little in precision. When choosing a gauge keep in mind your most accurate readings will be at mid scale of the gauge.

Faster

I may have miss read your post? Were you talking about valve spring installed height? If so you might want to watch>>>. https://www.youtube.com/watch?v=igDKPVxPtcc This shows you how to check installed height, then you next have to be concerned with valve stem height to keep all of that valve train (Geometry) at the correct angles. Seems like it never stops does it. And all you wanted to do was install some valve springs.

Honest Dad himself

This:
http://www.summitracing.com/parts/pro-66902/overview/

Awesome video, answered a lot of questions.

I used to be just plain old smart but now with the help of my puter i are plum Google Smarts. Good luck "Dirt" any thing you do in that motor requires a lot more than most people realize. Always look at your screw ups as learning experiences and keep in mind that asking questions might just help avoid a few learning experiences.

Honest Dad himself

Dad Bobby Motorhead Sp33dy thanks for the replies. I appreciate the help. That video was good. The micrometer is a neat piece. I think I've got a handle on it. Got an engine builder smarter than me coming by to lend a hand. Thanks again fellas!

Got another question for you guys. What's your opinion on titanium locks and retainers? Are they worth the price? Do they wear that much faster than steel? This is on a non-wing 410 with titanium valves. Thanks