Eric,
the red line is not set in stone. WST runs his car at 7500.
Two things have to be considered. His engine will not last 100k miles,
and he may have used higher quality components to make it more suitable
for higher revs.
That said, there are some things to be said about the redline of YOUR
engine. In stock trim, your engine will not WANT to rev above a certain
rpm (about 5000 I guess?), due to low compression, ignition timing,
inferior flow design, carb flow rate, and most of all gutless cam timing.
So in that respect you are correct in that your engine should like to rev
more with the mods you made. However this has little to do with the
redline which usually refers to a "safe" maximum rpm dictated by the
manufacturer.
There is a point above which one shouldn't rev, and that is when the
valves loose contact with the cam. This is referred to as valve ______
Hmmm, now I can't remember the expression (something like chatter).
You can eliminate this problem by using stiffer valve springs, but they
increase wear and rob power. They are not usually needed for street
engines, I feel.
The bottom line is IMO, drive the car the way it tells you it wants to be
driven. If it wants to rev to 6000, let it (it probably doesn't want to).
Ron Soave put it very nicely today, your engine is trying to tell you
sonmething.
Ulix
P.S. I like your web page!
On Wed, 26 Nov 1997, mumsy wrote:
> Hi -
>
> > My race Sprite runs all day at 7,500 RPM.
>
> Okay, I have to ask.
>
> I am new to rebuilding engines, rebuilding my 1500 now.
>
> What determines how high you can rev your engine? The red line, in
> other words. in stock form, my 1500 redlines at 5500 according to the
> tach.
>
> I'm putting in a beefier cam (Piper), weber DGV, bigger header, monza
> 1500 exhaust. If I put stronger valve springs on the head, along with
> all this stuff, would my redline go up? I'm curious as to how the
> redline is determined.
>
> thanks!
>
> eric
> --
> __.o,\____ Go, Lil' Racer! * Eric C. Mumford
> /__ \ / _ ) 1979 MG Midget * mumford@rpi.edu
> (+)`---(+) http://travolta.stu.rpi.edu
>
Ulix __/__,__
.......................................................... (_o____o_)....
'67 Sprite
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