7500 jdm cams, valve springs, manly h beem rods. usually shift at 6800 but have taken it to 7500 few times...
Even with upgraded valve springs, if your cam isn't making power up to 7,000 rpm, you're just beating up the valvetrain taking it north of the power peak. I probably could take mine to 7,500 rpm without remorse, but my max power number is likely in the 6,600 to 6,800 rpm range, so I have no reason to go there. Rev limit set at 7,000 rpm. Ported VMP Gen II with 10% lower, 2.5" upper. Rods are Manley I-beams.
So 2.5 upper stock lower?2.8kb pullied for 24psi, made 20psi on dyno cuz of cams
Boost may determine peak power, but the rpm it occurs is based primarily on the camshaft. Case in point, here is BJ's dyno numbers from an article in Ford Muscle with his new, built bottom end sporting 9.7:1 compression ratio with the difference between the two sets of numbers being camshafts only. BJ is not making any more power beyond 6,250 with his stock camshaft despite the fact that he's running 23 psi of boost. This is with a Gen II R, with a 15% lower and 2.4 upper. Boost is down 5 psi with the NSR cams. That's the same rpm power peak you'll see for a bone stock 5.4. There's no shortage of dyno charts in the sticky section of this forum that show the same thing from engines in between. I think the peak on the NSR cam is with his stock valve springs with 50k miles on them.The blower and pulley combo will usually dictate peak power more so than the cams will.
So 2.5 upper stock lower?
Boost may determine peak power, but the rpm it occurs is based primarily on the camshaft. Case in point, here is BJ's dyno numbers from an article in Ford Muscle with his new, built bottom end sporting 9.7:1 compression ratio with the difference between the two sets of numbers being camshafts only. BJ is not making any more power beyond 6,250 with his stock camshaft despite the fact that he's running 23 psi of boost. This is with a Gen II R, with a 15% lower and 2.4 upper. Boost is down 5 psi with the NSR cams. That's the same rpm power peak you'll see for a bone stock 5.4. There's no shortage of dyno charts in the sticky section of this forum that show the same thing from engines in between. I think the peak on the NSR cam is with his stock valve springs with 50k miles on them.
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Never do it on stock valve springs. I'm sure that cam has a lot more in it, but if the springs can't control the valves in the higher rpm range, it's a moot point.
I guess I don't understand your thread. I'm out.
I think he means that the valves will float if you spin it too high. Sure the cam probably has the capability but the valve train does not.
With a billet crank gear and oil pump gears and rods, 7000k at least.
BUT the key to your redline is your valve springs. Stock 07-12 id stick to 6500 unless your valve springs are also upgraded.
What are yall spinning the stock crank to with a built bottom end?
Also state what blower/pulley combo you are using.
Thanks.
With a stock crank I wouldn't go over 7500, Mihovetz says 7200 is reliable limit.