You got to the right answers alright. I just hope
I'm understanding them. What I envision doing
is having amotor that I can run gas on Saturday,
then change jets and whatever that night, and run
nitro-methane on Sunday. From what you and
others have been saying, I gather I can do this
with about a 8:1 CR if the motor is blown. I
believe the little Dodge is 8:1 or 8.25:1. I
think that with a good rebuild, good rods and
forged pistons, this motor could be a candidate.
Could I do this with 10:1 CR if the motor is
unblown?
Dick J
--- "Thomas E. Bryant" <saltracer@awwwsome.com>
wrote:
> Dick,
>
> Sorry, I didn't reply to the main issue in your
> question. I have not run
> gasoline with nitrous as yet. I would imagine
> that the same logic would
> apply as with the fuels without nitrous. Alky
> has a higher octane
> allowing higher compression ratios, but I will
> attest that Alky will
> detonate at 12.5:1 when you hit the nitrous
> switch. (Five pistons in
> about two seconds) If your tuneup isn't right.
>
> Tom, Redding CA - #216 D/CC
>
> Dick J wrote:
> >
> > What CR would be recommended for Nitro/Alky
> mix,
> > higher or lower than for gasoline?
> >
> > --- "Thomas E. Bryant"
> <saltracer@awwwsome.com>
> > wrote:
> > > Dick,
> > >
> > > It really depends on what you want to do, I
> > > guess. I have always used
> > > the same motor in both classes. I just
> build
> > > for Gas Class and accept
> > > that it will be a little less effective on
> > > Fuel.
> > >
> > > We run about 12.5:1 compression, I have
> found
> > > that it gets real
> > > difficult to get much more than 13:1 in a
> 302
> > > cu in Chevrolet motor. We
> > > do well on Alky, better when adding
> nitrous,
> > > and have run 33% nitro with
> > > good success in the 1/4 and 1/2 mile drags.
> In
> > > 1967, we ran 190 MPH at
> > > El Mirage in D/FR, at that time we held the
> > > D/GR record at 173.74 MPH.
> > > That was as far as I could run the engine
> on
> > > nitro without major
> > > problems, it was detonating severely at the
> end
> > > of the run. My best time
> > > at Bonneville on nitro was 196, I could
> never
> > > make it live past the 1
> > > 1/2 mile with all cylinders running. It was
> > > surely a great ride while it
> > > lasted.
> > >
> > > I was running a basic gasoline setup, just
> > > changing nozzles and jet, the
> > > fuel pump was a Hilborn "0" which didn't
> > > deliver enough fuel for the
> > > longer runs. Everyone told me that running
> that
> > > percentage on 12.5:1
> > > compression ratio wouldn't work and
> basically
> > > they were right, but I got
> > > by with it on the short runs and had a
> ball.
> > > Kinsler tells me that I
> > > could run up to 20% nitro with the pump and
> > > nozzles I am using for Alky.
> > > They recommend going 16% larger richer on
> the
> > > bypass jet for each 10% of
> > > nitro. Some day I'm going to try it again.
> I
> > > have five gallons of nitro
> > > that I have been saving for a long time.
> > >
> > > Tom, Redding CA - #216 D/CC
> > >
> > >
> > >
> > >
> > > Dick J wrote:
> > > >
> > > > Tom,
> > > > I was just cruisin through your website
> again
> > > and
> > > > noticed that you made the notation that
> you
> > > run
> > > > both gas and fuel under a single photo,
> which
> > > got
> > > > me thinking. Do you run both gas and
> fuel in
> > > the
> > > > same motor? Can you do it all at one
> meet?
> > > Or is
> > > > it a complete changeover from one meet to
> > > > another? I have often wondered what the
> > > > differences between fuel and gas motors
> were.
> > > I
> > > > know that gas motors run common CRs in
> the
> > > 10:1 -
> > > > 12:1 area, and alcohol runs something
> like
> > > 15:1.
> > > > What if they are blown motors, CR must be
> a
> > > lot
> > > > lower. What about unblown nitro motor -
> what
> > > > kind of CR does that run? And last, what
> > > about a
> > > > blown nitro motor - what CR do they run?
> > > >
> > > > I guess what I'm asking is: can a single
> > > motor,
> > > > either blown or unblown, be built to run
> both
> > > > gasoline and nitro, or alcohol with just
> > > simple
> > > > changes like timing and jets?
> > > >
> > > > =====
> > > > .............................
> > > > ..........Dick J.............
> > > > ......(In East Texas)........
> > > > ..........# 729..............
> > > > ........Roadsters............
> > > > .Hemis and Flatheads Forever.
> > > > .............................
> > > >
> > > >
> > >
> >
>
__________________________________________________
> > > > Do You Yahoo!?
> > > > Send instant messages & get email alerts
> with
> > > Yahoo! Messenger.
> > > > http://im.yahoo.com/
> >
> > =====
> > .............................
> > ..........Dick J.............
> > ......(In East Texas)........
> > ..........# 729..............
> > ........Roadsters............
> > .Hemis and Flatheads Forever.
> > .............................
> >
> >
>
__________________________________________________
> > Do You Yahoo!?
> > Send instant messages & get email alerts with
> Yahoo! Messenger.
> > http://im.yahoo.com/
__________________________________________________
Send instant messages & get email alerts with Yahoo! Messenger.
|