Aluminum head valve spring choice

[peabodyracin]

I recently picked up a new pair of Promaxx aluminum heads for a 440 I'm assembling. It appears from their website the only spring selection was for hydraulic roller. The guy I bought them from said they were roller springs. I'm running a solid flat tappet cam, .552 lift. I really only run one or two events during the season. The biggest one for me is a nostalgia event in Sept.

I just noticed on 440 Source's website they're selling a double spring for both solid flat tappet and hydraulic roller applications. This got me wondering if I can just run the springs that are on the heads. It seems there's more mass involved with a roller cam setup and because of that I wonder if the roller spring would be too much for the flat tappet setup. Hate to take out a camshaft in a fresh engine.

Opinions? Thanks in advance.

 

[HEMI-ITIS]

You can not use "roller springs" on a SFT cam. Spring pressure is less for a SFT than a roller.
Give Todd a call at The Moparts Connection Performance Parts - Discount Prices Main Index .He can set you up with the right springs!
He is my go to guy.

 

[Bird 426]

I agree, but the OP may want to see what he a actually has. Check his install height and open pressure first.

 

[DanielSlocum]

The way i see it......and people may disagree...... having more spring than necessary doesnt hurt other than its maybe some harder on lifters and rockers and cam lobe wear.
Not enough spring will only limit rpm capability and not actually hurt anything beyond premature valve float as far as i can see off the top of my head.
That said...iv seen several engines do just fine with a bit less spring than recommended.

 

[gkent]

Whatever you do, have the heads machined for and install steel spring seats.

 

[PRHeads]

You need to know what installed height the spring will be used at.

With the “correct” length valves, Comp cams steel retainers, 10* locks, and a .060” spring cup, the PM Victor copy heads will end up with about 1.900” installed height.
Change any of those components and who knows what you’ll get…….which is why it’s important to measure it on your heads, with your components……then select the springs accordingly.

I have seen a few sets of those heads(Victor copies) that have had incorrect length valves in them, and that can create a situation where the only viable work around is to replace the valves.

Depending on how aggressive the cam you’re running is, I’d shoot for springs that provide 130-150lbs on the seat, and 340-380 open.

 

[peabodyracin]

Thanks for all the good input! This confirms I think my doubts about trying to run the current springs on the heads. When I pulled one I was shocked at the length of the uninstalled spring compared to the 28006077 springs I was thinking of using. That immediately got me worrying about the valve stem length issue mentioned above, so I checked installed height and found that the existing were just about right on at the 1.83" the 077 need. So I'm comfortable at this point the valve stems are not too long or the valves sitting too low in the seat.

I should mention the cam is not a new one. I've had it in the former engine for some time and although it's seen limited use I've been happy with it overall. 1/8 times have been better than before but the car feels a bit soft on the top end. That got me thinking about the aftermarket heads and better valve springs. I couldn't see spending a bunch of money updating cast iron heads.

I am a bit baffled by the retainers that came with the Promaxx heads, as they don't fit into the 077 springs. Measuring the ID of the roller springs vs the 077 I get 1.12" vs 1.08" so the "step" of the retainer won't fit into the 1.08" spring. It appears the current Comp Cams style retainers on the market are sized for the larger spring ID.

 

[PRHeads]

Retainers come in all manner of sizes and fitments for different spring, stem, and lock configurations.
It’s no surprise that your old MP springs and the retainers on your PM heads don’t fit together.

Most cam companies offer a wide range of retainers to fit the various spring/stem/lock configurations……… you’ll just have to do some “shopping” to figure out what you need.

Are the heads you have the Victor copies?
If so…….You do know those require offset intake rockers, right?
And they usually end up needing a little relieving for intake pushrod clearance.

 

[peabodyracin]

You got me going there. The heads are the Maxx 210 on their website. They no longer appear to be available or the website is not being maintained. I'd bought these a year ago and at the time my checking had determined offset rockers were not required. Anyway, when I read your post I had to run back out to the shop to check again as I doubted my recall. Anyway the Crane roller rockers I have line up properly with everything (relief). I do note the 'tunnel' the pushrods go through is not terribly large, but visually it appears things line up OK. I'll have to check pushrod clearance to be sure though. Paranoia is getting me now.

The one thing I really liked about these was the angled spark plugs, which helps me with a tight clearance issue I've always had between #7 and the steering shaft. The engine short block is already sitting in the car pictured in the corner. Being an early A body things are a tight fit. Do you think I made a mistake picking these up? Time is going to be running out soon for me to make the Sept event so if I need to change direction it should happen soon. Thanks again for your input!

 

[PRHeads]

Disregard everything I said about the valve length and rockers.
Major brain fade on my part.
You said Promaxx…….but I was thinking “Pro Comp”.

I’m pretty sure the heads you have are the same castings as the Sidewinder heads, and some others.
I’ve never had a set of the actual “PM” branded heads here, but have done several sets of those castings……..no issues with them.

You’re right, the intake pushrod tunnels are not very generous, and often require some relieving when 3/8” pushrods are used.

 

[peabodyracin]

Thanks much for the info and your expertise! Guess I'll keep plugging on them. Thanks again.

 

[PRHeads]

This isn’t to say the springs that came on your heads would suffice, but…….I often use the same springs on SFT cams that I’d use on some HR cams.

If the heads came with springs for a SR cam……they’ll need replacing.