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Discussion Starter #1
Alright guys, got a few questions for y'all. I know this setup is not ideal, meaning I'm not surprised it's floating the valves, but I would think that with the given setup, it wouldn't float until around 7k. Here's the setup:

Comp Cams Magnum 286H-10 (hydraulic flat tappet) .490/.490 236/236 @.050dur, 286/286adv. 110LSA, 106ICL, Exhaust Closes 30ATDC, Exh. Opens 70BBDC, Intake Opens 35BTDC, Int. Closes 70ABDC.

The Cam calls for these springs:
Top: OD 1.065 ID .650
Bottom: OD 1.240 ID .825
Seat Load 110 @1.700
Open Load 292 @1.175
Coil Bind 1.115

I bought a set of patriot aluminum heads back in '08 (yeah, I know) and I used the springs furnished with the heads which are:
Max. Valve Spring Lift: 0.575''
Spring Pressure Closed: 115 lbs. @ 1.800''
Spring Pressure Open: 310 lbs. @ 1.225''

Which is over both open and closed spring pressure recommended, but for whatever reason, I'm getting some pretty nasty valve float starting at around 6k, and it's basically a rev limiter and hangs around 6,500 which is normally where I shift any way. Could this be a problem due to the apparent installed height issues the heads may have? I've read up that the installed height on these heads can be an issue, but this was on a big block forum, on BBC heads.

Anyway, I floated them pretty good today, and I'm wondering if there's any danger running it the way it is, basically what I'm asking is 1) given the valve timing events, is it possible to kiss the valves to the pistons, if I already haven't, and could it possibly eat a valve? and 2) Is this more of a problem with the heads do you think, or simply because it's a heavy hydraulic lifter? I know the ramps on the cam also effect how the valves act/float etc... But I've heard the ramps are "lazy" on the Magnum series, but I don't know that much about cams. I want to go to the track this weekend, but I don't want to go home with a hurt motor. I plan to go LS over the winter break, but would like to maintain drivability until then.

The Deck height is .015" Distance in the hole, and a .025" gasket, so .040" quench, if that gives you an idea of how close the valves are to the piston.

Sorry for the long read, I just wanted to give y'all all of the info, I know it helps. One last thing... I see guys running stock LS hydraulic roller lifters on some pretty aggressive cams, with $60.00 ebay china springs, and they spin to 7k with 15-20lbs of boost with absolutely no float. What gives?

Thanks in advance!
 

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The springs on the Patriot heads are probably Chinese springs. You have floated them more than once so you know the spring pressure is off. Buy the recommended springs before you blow the engine.
 

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If you are sure the valves are floating, then the answer to your question: "I'm wondering if there's any danger running it the way it is" is a definite "yes".

Check with the cam manufacturer for the correct recommended spring AND the recommended installed height. Check installed height. Check actual pressure on the seats. None of those tasks is that difficult and you can find relatively inexpensive tools to check them out.

Get the correct springs in there. .040 quench is a good thing. In fact, I am running .035 in a 4 inch bore. It helps ward off detonation.

Good luck.
 

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Discussion Starter #4
If you are sure the valves are floating, then the answer to your question: "I'm wondering if there's any danger running it the way it is" is a definite "yes".

Check with the cam manufacturer for the correct recommended spring AND the recommended installed height. Check installed height. Check actual pressure on the seats. None of those tasks is that difficult and you can find relatively inexpensive tools to check them out.

Get the correct springs in there. .040 quench is a good thing. In fact, I am running .035 in a 4 inch bore. It helps ward off detonation.

Good luck.
This is the reply I was looking for. It seems the springs are up to snuff, if they are what they say they are, and Patriot actually gets all of their parts in Alabama, apparently made in the US. I'm thinking you're right on the installed height, I will also test the springs to see where they're at. Luckily, my neighbor races, and will help me. I'll see when he can help and report back, should be interesting as there's not much info on how these heads are actually set up. I used to bash them when I first got them, but honestly, for $800 with yella terra rockers, they're a pretty good deal, and I know it makes at least 330 at the wheels being I have about 1/2 a length on my buddy with a ls1 '69 that makes right at 330whp.
 
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