[Tim Corcoran]

Yes, even with the heli-coil tangs broken off they are still about an 1/8 inch short of seating tight against the guide plates.

[Nobuddy]

Originally Posted by Tim Corcoran

The heads I received the holes for the rocker studs were not deep enough to install the studs all the way. I will have to cut an 1/8" inch off the studs to get them fully seated.

Similar on mine and depends on the studs and guideplates used. With the original tangs removed, ARP 100-7101 bottomed out. The blind hole is deep enough so I just wound out their coil, used a helicoil bottoming tap to add more threads, and also used a longer helicoil. I had the tools so cost me nothing.

Barry

[mysticmissle]

I trimmed the studs for the pair we have running
Many versions of the bbc 7/16 stud out there I went taller to get geometry where I wanted it
Cutting a little off the bottom Was not a big deal breaker for me

These are good Budget heads anyone that thinks otherwise hasn’t driven a car with them on

[Skip Fix]

I want to think I use ARP 7102s.

[grandam1979]

I had to shorten studs to fit factory iron heads just a month or so ago.

[chiefbigb]

Edelbrock guide plates are thicker. That would help with this issue but like a few others I just trimmed up the studs. I have run into this on iron heads also.

[mrennie]

Originally Posted by Johnny406

Does anyone know what the valve spring open/closed pressure is on the SM HR heads?

I'm looking for the same info, but for the flat tappet version if anyone has it handy.

[Johnny406]

Originally Posted by mrennie

I'm looking for the same info, but for the flat tappet version if anyone has it handy.

If you're running a solid flat tappet, the HR springs are quite adequate.

[mrennie]

Originally Posted by Johnny406

If you're running a solid flat tappet, the HR springs are quite adequate.

I bought the HFT version for a future project. Don't have a cam picked out but the spring specs would be helpful.

[Tim Corcoran]

Wouldn't Speedmaster be able to give you the spring rates? I'd give them a call.

[Steve C.]

Of interest......

https://www.speedmaster79.com/1.450-....060-Coil-Bind



.

[Steve C.]

I noted the springs linked above are the only set that are 1.450" O.D. at 1.800" installed which is listed for their Pontiac cylinder heads.
I presume they would use the springs they sell.
Also noted the 1.800" - 1.060" Coil Bind info listed does not correlate with their 0.580" max lift stated.

Side note, regarding the 1.800" installed height stated.
I've seen two posts regarding two different sets of heads received and they were measured at 1.780" and 1.825" installed height.



.

[Stan Weiss]

Steve,
This shows that many valve springs have those same differences listed.

Stan

[Steve C.]

Understood. But doing the
Math with it just doesn't jive with the max lift.

[Tim Corcoran]

Steve
your link has this below. Notice at the bottom is says those springs are for small SBC and SBF heads.

Brand: Speedmaster
Part Number: PCE272.1007
Part Type: Valve Springs

Number of Springs Per Valve: Dual
Outside Diameter of Outer Spring (in): 1.450 in.
Coil Bind Height (in): 1.060 in.
Damper Spring Included: No
Spring Rate (lbs/in): 130lbs @ 1.800 in.
Inside Diameter of Outer Spring (in): 1.080 in.
Inside Diameter of Inner Spring (in): .834 in.
Valve Spring Style: Standard
Coated: No
Quantity: Sold as a set of 16
Notes: Dual valve spring commonly used in aftermarket aluminum Small Block Chevy and Small Block Ford Heads.

[Stan Weiss]

Originally Posted by Steve C.

Understood. But doing the
Math with it just doesn't jive with the max lift.

Steve,
Maybe they are using different Math. By that I mean these springs may want a difference min distance at coil bind than we are normal use too.

Stan

[Tim Corcoran]

I cc'd the 78cc heads today and they measured 75cc's. I need closer to 80cc's, can I remove some material from the combustion chamber and get a few more cc's?

[Steve C.]

Tim,
I see what the link says regarding Small Block Chevy and Small Block Ford Heads. However they state their Pontiac heads use a 1.450 O.D. spring, and from what I gather at a 1.800 installed height.
That is their only spring that matches that criteria as far as I can find in their catalog.



.

[Dragncar]

Originally Posted by Tim Corcoran

Wouldn't Speedmaster be able to give you the spring rates? I'd give them a call.

Speedmaster ? I bought a fuel pump, 2 filters and a filler neck for my fuel cell.
Nothing from them comes with instructions ? Who sells a fuel pump with no instructions ? Not even a "in-out" on the pump or what amp fuse to use.
The fuel filters, one 8AN has O rings on the caps. When you tighten them by hand you can not feel the O ring contact the tube. I think it will leak unless I change it to O rings that seal.
The other filter is a 3/8" hose deal and the nipples are barely long enough for a hose clamp and the little bump on the end is not big enough for my liking. It was 8 $ so what the heck.
Not saying none of this stuff will not work but you have to double check everything.
Simple instructions would be nice.
I guess they feel they can just copy what they want and put it out there without any.
Hey, they stuff was cheap but the you get what you pay for rule applies.

[mrennie]

Originally Posted by Tim Corcoran

Wouldn't Speedmaster be able to give you the spring rates? I'd give them a call.

Probably, but was looking for actual results if anyone had measured them on a tester. I have no doubt SM can give me specs but I have trust issues. Will likely measure them myself prior to doing anything but was just curious if anyone had some existing experience.