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.
> > > .............................
> > >
> > >
> >
> __________________________________________________
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> =====
> .............................
> ..........Dick J.............
> ......(In East Texas)........
> ..........# 729..............
> ........Roadsters............
> .Hemis and Flatheads Forever.
> .............................
>
> __________________________________________________
> Do You Yahoo!?
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