[Shotimes] (OT) Marauder

[David P]

Listen up guys, we are talking about 4V OHV, which would NOT be an OHC
design, IOW we are talking about "V" configuration motors. It's obvious
we've had had SOHC designs for quite some time, just look at 4cyl inline
motor history.

Ron,

    Checked on gas mileage ratings of any Corvettes that run higher gears?
Found any near 30mpg?

And, yes, Ferrari proved many years ago that 5 valves is better than 4 both
on cramming more air into the motor AND on improving emissions I don't know
what Audi has done, as I'm not inclined to care about them much. They could
be worse for all I know, because efficiency is going to be a factor of
design, and we all know that some mfg's put a bit more money into their
designs, but all things being equal, 5 valves should perform better than
four. Think about it. With 4V, you have two specific point of entry for
intake charge, and they are both on the same side of the cylinder. With 5V,
you can place another valve in the dead area in the center of the bowl,
right between the four other valves, with minimal size reduction to the
other valves. You've now reduced intake charge resistance (more power with a
longer stroke), and the charge does not enter just from 1 side of the
cylinder (more equal spread of the charge mixture for a more even flame
front which produces more power and more efficiency).


David P

95MTX



~
----- Original Message -----
From: "Ron Nottingham" <nottingham@alltel.net>
To: "David P" <jpotter8@bellsouth.net>
Cc: <shotimes@autox.team.net>
Sent: Monday, November 04, 2002 09:36
Subject: Re: [Shotimes] (OT) Marauder


> ----- Original Message -----
> From: "David P" <jpotter8@bellsouth.net>
>
>
> > Since all OHV motors are two-valvers, and four valves allow more
efficient
> > combustions, then pushrods DO have a bit to do with emissions, at least
> > until they figure out a way to cram 4V onto a single cam. Sure, injector
> > placement, intake flow, etc play a large part, but when considering
solely
> > 2V vs. 4V, 4V is going to win on emissions and power. You think maybe
> there
> > is another reason why the Corvette runs a 2.73 final?
> >
>
> Uhhh, David, they have already "crammed" 4V onto a single cam...  Go check
> out most Hondas...  4 valve SOHC's have been made for a long time!  Not
just
> by Honda either.
>
> BTW,  the Corvette runs a 2.73 rear gear because with the torque
production
> it makes, it can AFFORD to run a high gear.  With a high torque engine, a
> higher final drive ratio is more beneficial.  But another thing that needs
> to be considered are the gear ratios in the tranny.
>
> And taking your reasoning, Audi's 5-valve engines will win on emissions
and
> power over all 4-valve engines :-p
>
> Ron N. - Dalton, GA
> 90 SHO