High throttle miss

[Texasdoc]

Ok, just got a call from the shop. At least one broken valve spring. He said these springs are only good for 6000 rpm and up to 600 lift. I need springs for 7000 (I run up to 6000) and 650 lift (I have 610).

Any spring recommendations? I will probably need new retainers, etc. Anyone have a good site where I can get info about spring size, height, shims, pressure, etc. Also info about how to correctly setup everything?

It's weird, AFR says the stock springs that come on these AFR 195 renegade heads can handle 7000 and 650... Maybe they changed them at some point.

[DWRAT]

Originally Posted by Texasdoc

He said these springs are only good for 6000 rpm and up to 600 lift. I need springs for 7000 (I run up to 6000) and 650 lift (I have 610).

AFR 195 Renegade heads are rated to 7,000 rpms per ARF specs.
I'm betting you have a different problem causing your misfiring.

[Texasdoc]

Originally Posted by blykins

How many broken springs did they find?

They took the driver's side valve cover off and found "at least one" broken inner spring. I don't think they did any more than that. Once he found the broken spring he called me to see what I wanted to do. The labor alone on replacing them all was quoted as $1k. He was going to go"talk to the machine shop" to see what springs they recommended. I don't know anything about their machine shop, and I trust Brent, So I just told him to put it all back together and I would do the work myself.

Originally Posted by DWRAT

AFR 195 Renegade heads are rated to 7,000 rpms per ARF specs.
I'm betting you have a different problem causing your misfiring.

That's if AFR used the same springs when I bought these heads as they do now. Yes, the current springs are rated for 7k, but I read on other sites that previously the 7k springs were an option, not standard. They have since started using the better springs as standard. I don't know which springs I actually have.

The shop guy said a spring was broken. He said they were only rated to 6k and were weak. I didn't ask how he decided that. Either way the springs need to be replaced if there is a broken one.

When I get it back tomorrow, I'll see if I can figure out what springs they actually are, then find their ratings. They should be painted with a color stripe for identification.