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I would think that the hydraulic grind does not maximize the solid roller lifter advantage. But they can run together. I've seen it but the power was only equal but elevated by 3-400 RPM in the band. |
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Yes, you can increase the rpm capability of a hydraulic roller and the gentler ramps of a hydraulic roller is easier on the valvetrain.
Only issue is that valve lash is usually a lot less than with a normal solid roller application, to the point where you set cold lash at almost 0. |
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Right, you just have to make sure that you get it right, or you could keep the valves hung open at cold startup.
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Again I really appreciate everyones input. Not trying to start arguments. Just trying to find a solution to my problem. With the economy the way it is I also feel the crunch which I can't afford to swap out my entire valvetrain. I already had the cam fixed so I can't justify getting rid of it, not to mention my custom length pushrods(took 5 weeks to get),valve springs, etc. Brent, my advertised duration is in 288 and ex is 292 @.050 252 in and ex 255. Lobe separation is 104....valve spring data open ht.1.250 @lbs400. Thanks agai. Berm
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Stay away from any roller lifter for street use due to excessive maintenance, stress and expense. I went through two sets, one non oiling and the next HPPO (Crower). After the second set sent ground up needle bearings through the engine I changed out to ceramic coated solid flat tapit and are happy that I did. Two times off the road was frustrating.
You need to put in perspective what you use your car for and make your decision based on what sort of useage your into. |
Well the situation is trying to preserve monies all ready invested, cam, valve springs, pushrods primarily. Doesn't leave a lot of options. Back to solid roller or POSSIBLY pressure fed solid roller. PF roller may require another set of push rods though depending on size/legnth of the new lifters.
Solid roller cam profile; would that rule out hydraulic rollers 100%? |
Ernie, you'd have to have very light weight valvetrain in my opinion to get away with running hydraulic lifters on a solid roller profile.
I tried a custom camshaft in a 445ci Windsor once. It was a hydraulic roller with very steep ramps. Even with titanium valvetrain components and 150/425lb springs, it was lofting the lifters and floating the valves. Not good. Berm, That is a very large cam to peak at 5900. I'm wondering if you've had excessive lash problems, or even valve float issues all the time. Something is up as that cam with those good heads should make power up high. Also, what is the seat pressure on those springs? Normal SBF install height is around 1.800-1.850, so if you have 400lbs at open pressure, that's not enough. Nowhere close. Your seat pressure with that cam should be around 200-250 lbs with about 550 at open pressure. The springs could have caused both problems.....loss of valvetrain control, and loss of power up top. I would check seat pressure and post back here, but at this point, I would send them back and let us help you get new ones. If you want to keep that camshaft, then a set of pressure fed lifters would work just fine. You can get a set of Comp pressure fed lifters for $339. |
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I agree Vector.
That may explain why the lifter failed....and if the seat pressure is where I think, it would explain why the power went away at 5900 rpm. That motor should just start pulling hard at 5900. |
springs
400 lb open is way too low for that roller cam with steel valves, especially if with steel retainers, heavy aftermarket roller rockers, etc. That would even be marginal with titanium valves. Almost guaranteed that is the problem.
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What I should have done was scan my cam card. So here it is. I need to talk with my machinist where I am at on my springs. and I will get back to ya. Ultimatley I am trying to salvage the valvetrain. I haven't taken any short cuts and not wanting to start now . Here is my cam card. Berm
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i posted earlier about your peak hp rpm, i was wrong and not considering the lsa. i haven't seen too many 104's. i was looking at an article with a 406 and they tested three different cams at 107, 110, & 113, all peaked tq at 4800, 4900, 5000 in that order, but the hp was reversed 6300, 6200, 6200. looked at one of the cam sites and closest lsa was 106. looks like you have a circle track cam, going to have a narrow power band btw. i think you could do better with cam selection, some of the guys here could help. ask your machinist if the top end has oil restrictors.
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My understanding the tight lsa is to bring the torque #'s at low rpms which it did on the dyno. I know there are restrictors at the mains but I don't know about the top end. Where would the resrtctors be for the top end. The back of my block is tapped for threaded plugs but in the lifter galley I have the press in plugs. Berm
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If you are running the AFR race ready heads with the standard springs they are 225# on the seat. But, those springs are very cheap, low quality, offshore items that go away quickly compared to hi quality springs. I broke an AFR inner spring at a track day and lost 500 rpm instantly. Had I broke an outer spring I would have lost a motor. Seat pressure was good before the event. IMO, when running a solid roller on the street, afford the best springs you can run.
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Money an issue? Flat tappet cam is cheaper than any roller combo.
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