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General question about higher redline.

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Old Jun 12, 2006 | 07:29 PM
  #1  
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Default General question about higher redline.

I noticed that on some dyno videos whoever drives the car (on the dyno) sometimes go above the redline... which should be dangerous(?)

I also understood from a friend that the main issue with going above the redline is because the motor runs too fast which cause less oil to get to the right places...

so I was wondering what if you use a thicker oil (synthetic?)?

I know that it might sound stupid... but I just started to really learn how engine works (I'm only 19 )


Thanks.
Old Jun 12, 2006 | 07:38 PM
  #2  
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Default RE: General question about higher redline.

the oil thing might be true but you are also looking at the mechanical limits of teh stock bottom end of the engine. Put some forged internals in and rev that thing to the moon, the moon i say.
Old Jun 12, 2006 | 08:07 PM
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Default RE: General question about higher redline.

the valves can cease to open and close at the correct time if you rev too high.
Old Jun 12, 2006 | 08:14 PM
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Default RE: General question about higher redline.

ORIGINAL: redass02gt

the valves can cease to open and close at the correct time if you rev too high.

I guess I have to put a VTEC sticker on the back window, huh?


How about if I'll rebuild the head with high tension springs?




anyone knows if that would be enough?
Old Jun 12, 2006 | 10:56 PM
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Default RE: General question about higher redline.

Why do you want to rev your engine higher? Haven't you noticed on most of those dyno sheets, max HP/torque has usually already occurred BEFORE reaching max RPM? So not much point in revving the engine past tolerance is there?

Old Jun 13, 2006 | 12:24 AM
  #6  
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Default RE: General question about higher redline.

Not sure about the oil thing, although i believe a thinner oil would help rather than a thicker oil, because it is easier to pump. Either way, your oil should be chosen based on operating conditions and clearances in the engine; to increase oil going to the crank, usually restrictors are put in the lifter valleys (something like that, prevents so much oil from going to the head and redirects it to the crank)

+1, depends on what setup you have in your engine. If you have a forged, balanced bottom end, that thing will rev as high as the bolts will hold it together for (granted the proper springs etc are installed)

It depends on the h/c/i (heads, cam, intake) on where your engine makes power. If you've got 225 cc intake runner heads (extremely large for a 302) coupled with a high rise carb'd intake manifold or a box F.I. manifold, and stick a cam with .650 inches of lift on there, you'll need to rev over 7k rpm just to make some power.
Old Jun 13, 2006 | 03:19 AM
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Default RE: General question about higher redline.

on a related note(or at least i think) what does floating the valves mean??

here is my guess.....oh and im 17

revving so high the valves almost get shot open, or pushed open so fast that they lost contact with the cam and stay open too long.....or am i way off[&:][&:]
Old Jun 13, 2006 | 09:23 AM
  #8  
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Default RE: General question about higher redline.

Yes valve float means the cam is spinning so fast the valve spring doesn't have enough time to close the valve before the cam lobe pops it open again. Heavier valve springs will solve this problem, but can increases valve lobe wear.
Old Jun 13, 2006 | 11:51 AM
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Default RE: General question about higher redline.

ORIGINAL: weasel1088

here is my guess.....oh and im 17

revving so high the valves almost get shot open, or pushed open so fast that they lost contact with the cam and stay open too long.....or am i way off[&:][&:]
yeah, that's was my guess as well, and that's also why I mentioned 'high tension springs'.

I was sure I'm the youngest on the forum, it's good to know young guys like me who like mustangs! [sm=happybounce.gif][sm=smiley20.gif]
Old Jun 13, 2006 | 06:15 PM
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Default RE: General question about higher redline.

wait a second....i though syth. oil was less thick than regular?



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