How high can stock valvetrain reach? do I need to upgrade?

[OmarM]

I am wondering how high I can rev on stock valve springs? I need to decide whther or not I should upgrade my valve springs, or just buy a decent cam. I was thinking a 260degree cam with 8.8mm lift. Would I need valve springs for that?

[boost_boy]

I am wondering how high I can rev on stock valve springs? I need to decide whther or not I should upgrade my valve springs, or just buy a decent cam. I was thinking a 260degree cam with 8.8mm lift. Would I need valve springs for that?

Why not upgrade if you're going to go as far as put cams in it. It sure won't hurt it. Stock valve train is good for about 8400ish rpm, but the valves are already floating at this time, so you be the judge.

Dee

[Swedish Mike]

Yeah, I´ve been running 8500 rpm on stock valve train and light weight pistoms.Used this set up for a year before I sold the car and I don´t know if it workes today. Would never do this on a customer engine but funny to try on your own car if you got a lot of spare parts.

/Mike

[Akihisa]

The stock retainers do not like stiffer springs and 9k+ rpm.

[boost_boy]

The stock retainers do not like stiffer springs and 9k+ rpm.

That's not true! The stock retainers can care less if your springs are doubled, tripled or whatever. If your retainers are fatigued (regardless of what they're made of) they will cause a catastrophic failure. I've never had one failed and I've owned enough CA engines.

Dee

[OmarM]

Well did car run fine for a year before you sold it, cause I plan on having my motor rebuilt with forged pistons and all new gaskets and pumps, so i assume 8000 rpms on stock valvetrain should be fine with 8.8mm lift cams, what do you think?