I'm looking for a set of springs for a 509 cam that will work with a unmachined 906 heads and my stock retainers. I've read that take offs from Performer RPM's will work - but can I use my stock retainers? What diameter springs will fit the stock? Any suggestions? I'm trying to go the cheap route...

If it turns out that you can use the edelbrock springs, I have 2 brand new sets that I replaced the springs from RPM heads that you can have cheap. Never used...just taken off.

Thanks to Zippy I ran the Edelbrock performer RPM springs with a 509 cam with no issues, I think I reused the stock retainers and locks too.

Thanks for the reply.

Do I need to cut the spring seat?

Does anyone know? Will the edelbrock springs fit on the stock head without machining?

Thank you

What ever happened to Zippy and the GTX? He is a cool cat.

I definitely don't remember the seats needing machining, but this was like 12 years ago and my memory is fading!

Zippy is on facebook, he is more heavily involved with music now. I don't think the GTX has been out much but he did put the old 440 from his GTX into the '72 Polara he had.

I used the Mopar P3690933 Hemi springs with my 509 in my 383 with no problems.Ran it to 6500 rpm's.

From Edelbrock catalog:

Valve spring diameter: 1.55"
Valve spring maximum lift: .600"

R.

That Edelbrock 1.55" spring has a seat load of 140lb at 1.880 installed height and a spring rate of 354 lb/in. For a .509 cam it'd have 320lb over the nose. Coil bind is 1.160" It appears to have enough margin for close to 0.700" lift.

Is it too much for a hydraulic flat tappet cam?

R.

The MP 0933 and the Comp 911 springs work great w/ the 509 cam. Don't think you need to cut the spring seat at all. Don't know about the stock retainers...I throw all the stock stuff away. I never measured to see how much lift you can run on stock heads w/o cutting the guide bosses down...I always cut mine down low and use positive type valve seals.

If you use Edelbrock springs, have them tested and install them at whatever height gets you to 130-140 closed pressure.
It would appear that Edelbrock has at least a couple of different vendors for that spring and they def aren't all the same.
Don't assume they are the same as the spec in the catalog. Sometimes they are, sometimes they aren't.

Thanks everybody for the help!

Chargerfan68

Check your messages please.

Dodgeballs, you have a PM

Hey guys - another question or two. I want to get some new retainers and locks for the 1.55 edelbrock single springs. I have stock valves in the heads. When I look for locks for stock valves, I find 4 groove for the exhaust valves (which is what I have), but 2 groove for the intakes. But my intake valves are single groove, I have two sets of 906 heads and both of them have intake valves like this. I guess I'm more concerned about getting the right intake locks since I am only seeing 2 groove retainers when I search for them (at least for the stock retainers).





Valve off other 906 head:




Should I get one of these these retainers?:

Comp Cams 780-16
or
Edelbrock 9644


And for locks?:

Comp Cams 604-16 (4 groove for exhaust)

Comp Cams 603-16 (1 groove for intake)



Sorry, I have never replaced retainers/locks before and want to make sure I get it right.

Thanks

What are the retainers in the picture? Almost looks like titanium. Hard to tell, but shiny

Aluminum I believe. One cracked so I'm changing them. I think they were put on in the 70's or 80's.

Here's a pic of the lock for the intake valve. I guess 2 groove valves were common on other BB heads, but the 906 had these single groove valves?



I went and ordered the Comp Cams 603-16 single keepers. I hope they fit.

Those aren't stock intake valves. The single wide groove is pretty much the industry standard and better than the factory setup. Every stock head I've disassembled had 2 and 4 groove locks.