I can't speak from B-Ville experience but from my drag racing experience, if
you were to run steel rods in a blown fuel motor , I would think you would
break the crankshaft , like right NOW!
I think most of us that have used aluminum rods did so to save money , not
because we needed to absorb shock. In a unblown gas application, a aluminum rod
may serve the purpose.
C&A offers a 7075 rod that is very good for Blown Alcohol . They also offer a
'Deep Cycle" rod that the Top Fuel guys use ( I forget the alloy ) , this rod
is softer ( absorbs more shock~ nitro detonates ). I have great luck with
Brooks 6061 rods in an alcohol digger.These rods are not cheap. The less
expensive rods are not made to the same standards as these are.
>>> "Ferguson, Darrell" <dfergus@bactc.com> 07/09 12:06 PM >>>
I've been lead to believe that one of the benefits of aluminum rods is that
although they have a much shorter duty cycle than a steel rod, In a
supercharged fuel motor, they absorb a little bit of the shock generated by
high cylinder pressures, and help save rod bearings and crankshafts as a
result. Any blown fuel guys to lend any credence to this ?
Darrell Ferguson
BLACK RADON ENGINEERING
# 939 BBFALT
http://my.cybersoup.com/blackradon
> -----Original Message-----
> From: dahlgren [SMTP:dahlgren@uconect.net]
> Sent: Friday, July 09, 1999 5:34 AM
> To: Land-speed@autox.team.net
> Subject: Connecting rods
>
> In my humble opinion there are not too many places for aluminum rods
> other than a few selected applications where a little flex is desirable
> to take the load off the cylinder walls. With the availability of new
> stronger blocks and filling techniques the need for alloy rods seems to
> be very small. They are cheap though not really that much lighter. The
> rod of choice has always been a carrillo for me with crower as a second
> choice. I have never broken one of either in my life. I have lost an
> engine or two but not from a con rod failure. Have also had good fortune
> with titanium rods but they are a pretty fussy thing to get them right
> and are much less forgiving and harder to work with in general. But they
> are light and very strong. If you need a set of rods for me you call
> carrillo pay what they want and never think too much about them again.
> Just the best overall solution. Along with that a real good crankshaft
> that won't twist and flex like a pretzel is the next and as important
> thing Moldex if you have the time,Crower is good for me also, we run a
> Cosworth one which is a billet piece but it is a Cosworth engine also.
> Pistons my favorite is JE but there are many companies that are also
> good that I have not worked with. My plan has always been to find a high
> quality company and stay with them through thick and thin and don't hop
> around like you are at a buffet every time you need something. the other
> thing not mentioned is as or more important. A good oiling system as in
> dry sump and very high quality. Weaver for me. Never broke one yet.
> Never had one fail. Just use the best that money can buy. best lines
> real Aeroquip for me. Is for aeroplanes get it. I don't think i would
> fly with a brand X look alike to save a dollar or two. I would not risk
> me or my car either for a dollar or two. A friend lost a very nice 350
> SBC the other day because a brand X hose end failed on the dry sump
> system. Indy type car for new race series. Was way too busy driving and
> in a few seconds engine was gone.
> This is only my opinion and I may be wrong.... Your mileage may vary,
> Not covered by FDIC...and all the other disclaimers...
> Dave Dahlgren
> Engine Management Systems
>
> Chuck Rothfuss wrote:
> >
> > Jerry, Keith,
> >
> > Wasn't something said awhile back about aluminum rods stretching and
> > whacking thing they shouldn't during sustained high RPM operation? I
> don't
> > have to worry about that myself (No rods!) but I still have loads of
> > clearances to check during engine assembly. Unless you like to build
> lots
> > of short lived engines (Keith?) then it's best to put all the most
> durable
> > stuff you can afford into it right up front. You need to find a balance
> > somewhere between drag racing and NASCAR; Maximum performance with
> maximum
> > durability. At least enough of each to break a record!
> >
> > Chuck "We don't need no stinking pistons!" Rothfuss
> > ECTA
> >
> > >> On Thu, 8 Jul 1999, JERRY FOSTER wrote:
> > >>
> > >> > #1 Car weight. Do you build for super-light cars in the LSR
> business?
> > >>
> > >> There are two basic schools of thought in LSR racing. The "bigger
> hammer"
> > >> racers do things like fill their frame rails with lead, and carry
> fifty
> > >> gallons of water in the trunk, all in an attempt to gain traction.
> Others
> > >> feel that a lightweight car that sticks to the track thanks to good
> > >> aerodynamics will be quicker, faster, and ultimately safer. I belong
> to
> > >> the latter group, as does my boss, Russ Meeks, whose Modified
> Roadster
> > >> carries no ballast whatsoever.
> > >>
> > >> > #2 Engine assembly weight. Do you go with aluminum rods, small
> > >> > damper/balancer, lightweight crank, etc,?
> > >>
> > >> That depends on what you want the engine to do. It's not a dragster,
> so
> > >> some extra reciprocating mass may in fact be a good thing. Five miles
> is
> > >a
> > >> long way. Visualize yourself making a run on a track that long. Then
> > >> contemplate how you would want your car to handle, and how its engine
> > >> should respond. Think of what a flywheel does. Do you want more or
> less
> > >of
> > >> its effect?
> > >>
> > >> These differences in opinion are just more of the appeal of Land
> Speed
> > >> Record racing. We get to experiment and play around more than any of
> the
> > >> other racers.
> > >>
> > >> Regards,
> > >>
> > >> Dave Mann
> > >>
> > >> Webmaster, Roadsters
> > >> http://roadsters.com/
> > >>
> > >> -----------------------------------------------------------------
> > >> | Dave Mann | Roadsters Advertising: |
> > >> | Roadsters | Dave Rocha |
> > >> | P.O. Box 67101 | (360) 835-8661 |
> > >> | Milwaukee, OR 97267 | dirtno1@aol.com |
> > >> -----------------------------------------------------------------
> > >>
> > >>
> > >
> > >
> > >
|