Valve spring recommendation?

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turbovan

turbovan

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I installed a craigslist 360 to get my project car on the road, and I believe I'm running into valve float at 5200. Engine is from a circle track car, and although not exact, cam is close to the howards 712901-12. https://www.summitracing.com/parts/hrs-712901-12/overview/make/dodge

the Howards website does not list valve springs, but summit says they're required. The springs are currently stock or close to it with roughly 80lbs on the seat, hydraulic lifters, and it has heavy 2.02 stainless valves installed. The engine also sat in storage for 3 years which I've read doesn't help my situation.

Am I right to assume I am experiencing valve float with this combo, and can anyone recommend a replacement spring?
 
Must be for a stock lift and stock springs type of class. This cam ain't gonna be a great 'cruising around' cam. As the springs at the stock installed height of 1.650"? If so, maybe look at Hughes 1110's (which sure looks like a Melling 466434....). There may be cheaper Melling single springs if you want.
 
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I know the cam isn't optimal, but the engine is being used to sort out a fuel, and ignition system for another build. I was considering the comp 942-16 springs, but i have seen the hughes 1110's suggested often on this site.

Yes, they are installed at the stock height.
 
They look to be essentially the same spring rate and almost identical closed and open specs. And the Comps look to be cheaper. Open pressure will be around 260 lbs for that lift.

How hard do you have to run things to sort this out? LOL
 
lol
I want ~6200 rpm out of it. After I sort fuel, ignition, and the transmission I'm building a turbo setup using this engine as a test mule while I build a long block. Right now it wants to idle at 1K rpm with 10 inches of vacuum and 22 degrees initial timing...i'm trying to live with it. I feel the 942's give me some room to grow if i decide to ditch the cam.
 
Howard catalog shows spring 98438, retainer 97110. Odd thing is it says dual spring.

425 lb rate. 122lb/1.65" 353lb/1.10".
 
Coronet 500 said:
Howard catalog shows spring 98438, retainer 97110. Odd thing is it says dual spring.

425 lb rate. 122lb/1.65" 353lb/1.10".
Click to expand...
I can't find this on their site. Are you looking at a physical catalog?
 
in that case maybe the comp 926 is closer, but is that spring rate because up the 6500 rpm range?
 
The Comp and Hughes rate numbers are very close to each other; so close as to not be distinguishable. The Howard part mentioned is a big step up again. One thing in the back of my mind is that you are going to step up lifter-to-lobe pressure on an already broken-in cam; a BIG step up in pressure might be a problem. I would certainly put in break-in oil and go through a new break-in procedure.

I'm gonna bet that the Comp or Hughes PN's will go to your RPM; that RPM is not horribly high, and that is a pretty typical spring for all sorts of cams in the .400-.500" lift range.
 
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