To start off the motor is a 95 1.8 out of a miata and the head casting number is #BP05-4
the car is turbo and i have the head off "again" because I did not specify a MLS surface finish when I got the head machined...
I am a Machinist so I should have known to specify the surface finish when I dropped it off.

While the head is off "again" im thinking about replacing the stock valves and springs with something a little better.

so far my options seem to look like supertech or flying miata which their spring kit has extremely similar specs to the super tech kit and I'm thinking they are the supertech brand.

My question is, should I upgrade the springs and retainers? I have not experienced valve float with a max rpm of 7000 rpm "yet" but they might be a nice piece of mind, they are just kind of pricey so i would like to know how necessary they are.

also should I put in supertech valves while its off as well and lap them in so they seat properly?

I know many of these questions have been answered and yes I have used the search function but I figured some of you more knowledgeable folks could shoot me a link or tell me exactly what I need to do.

I understand that with the retainers you need keepers from an NB and those are expensive as heck, so what do you guys do to get them cheaper or do you just pay the $175 for them?

thanks for any answers to my questions!

 

save your money for an nb head

 

hmmm... I like the way that sounds. Ill have my current head resurfaced and put it back together to get my car up and running then save money for the NB head and maybe put that on this winter.

Thanks for the input.

 

Unless you have big cams or spin 8k+ RPM stock springs are fine.

I have larger cams in my engine and spin 8k no problem with no float on stock springs, but I run SUBs which lightens the valvetrain.