Now there was a thought we can Play with....
The motor basically just kept getting hotter as the RPM increased.... I was
wondering if I had enough Fuel Flow .... the Pressure was set on 7.5 but we
noticed as the demand increased off Idle it went down to 6 and seemed to
stay there.... hard to tell as I was in the car and I don't have a Pressure
gage in the car...( brad was peeking over the edge of the engine
compartment)
I am running a Barry Grant 280 which is good to about 650hp... which is
just under what we are making at the crank.. on this motor...
K
----------
> From: Thomas E. Bryant <saltracer@awwwsome.com>
> To: Bill Bennett <benettw@earthlink.net>
> Cc: land-speed@autox.team.net
> Subject: Re: Fw: Carb sizing/ ignition timing
> Date: Monday, May 15, 2000 9:32 AM
>
> Bill,
> I don't know what carburetor you have, but I assume it is a Holley. The
> Holley power valve is vacuum operated and changing power valves only
> results in altering the level of vacuum that opens it, the actual
> metering is done by restrictions in the metering block. What timing
> settings have you tried? You could do away with the power valve and run
> main jets only, but of course this would make it rich in the mid range
> when you got it right on the top. Another thought, make sure that you
> have adequate fuel supply, there may be something the is restricting
> fuel flow which would make it lean out under high demand.
>
> All of this 'great' advice comes from someone who hasn't run carburetors
> on a race motor since I had six Stromberg "97" on a 300 cu in Desoto
> back in the very early sixties. I do know though that problems like this
> often have a simple fix. Back to the Basics!
>
> I am still a believer in throwing out what others do and finding what
> works for me. Combinations are the key. Some run leaner with less timing
> and others may try more fuel and more timing. Although I have not often
> had the opportunity to do it, the dyno is a great place to experiment.
>
> Tom, Redding CA - #216 D/CC
> Bill Bennett wrote:
> >
> > ----- Original Message -----
> > From: "Bill Bennett" <benettw@earthlink.net>
> > To: "Thomas E. Bryant" <saltracer@awwwsome.com>
> > Sent: Sunday, May 14, 2000 10:55 PM
> > Subject: Re: Carb sizing/ ignition timing
> >
> > > Strange as he would say this. I have seen so many jet changes done
> > on
> > > this motor going bigger each time till it slowed down. The motor
> > seems
> > > to always want more gas. I wonder does the power valve have anything
> > > to do with it. I know they made a couple of different types some
> > > flowed more than others. On the street motors I have built I had
> > > always just measured the vacuum at idle and sized the power valves 2
> > > inches less. I never worried about the flow rate. Don't know about
> > > race motors.
> > > BillB
> > >
> > > ----- Original Message -----
> > > From: "Thomas E. Bryant" <saltracer@awwwsome.com>
> > > To: "Keith Turk" <kturk@ala.net>
> > > Cc: <land-speed@autox.team.net>
> > > Sent: Sunday, May 14, 2000 10:20 PM
> > > Subject: Re: Carb sizing/ ignition timing
> > >
> > >
> > > > Keith,
> > > > Sounds to me like it is lean in then power range. At light to mid
> > > range
> > > > cruise the main circuit supplies the fuel, when you lean on it the
> > > power
> > > > circuit has to provide extra fuel.
> > > >
> > > > Tom, Redding CA - #216 D/CC
> > > > Keith Turk wrote:
> > > > >
> > > > > Saw something interesting the other day on the dyno thought I
> > > would ask
> > > > > about it...
> > > > >
> > > > > with the Engine at 3000 rpm the egt was around 1200.... as I
> > > rolled into the
> > > > > throttle and the Rpm started Rising so to did the EGT ...
> > actually
> > > getting
> > > > > to an unacceptable range based on my EGT gage and the motors I
> > > have run with
> > > > > this set up.... I want to see about 1375 and it was well over
> > > 1500..
> > > > >
> > > > > So my Question is if the Carb was to big how would that manifest
> > > itself...
> > > > > and if the ignition timing was to far advanced what would I
> > > see.... any
> > > > > thoughts?
> > > > >
> > > > > Keith ( Nahh I ain't totally clueless... Just Bored ) ( Hey
> > Mom..
> > > Happy
> > > > > Mothers day)
> > > >
> > >
> > >
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