Red Sled runs 130 MPH in the 1/8

[BAD4DR]

Quote: Originally Posted by bayshore power

Urban legends abound in the gearhead community. One is: aluminum connecting rods don't work in street engines. Prior to the mid-'70s, that might have been true, however, introduction of the Bill Miller Engineering Forged Aluminum Connecting Rod in 1975 provided an exception to that myth.

The BME Rod has good durability in high-end, high-power, street/strip or hot street engines because it is die-forged, rather than cut out of an aluminum plate. Bill Miller Engineering's unique, high-strength, aluminum alloy further enhances fatigue strength such that the potential durability of BME Rod rivals that of many forged steel rods and exceeds that of a few.

That would be true in applications where extreme knock is a possibility, or you're running a mix of an explosive fuel, but simply put, that's mostly propaganda from an aluminum rod manufacturer. Fatigue resistance of a properly designed forged steel rod in a normal application far exceeds the best aluminum can offer. To the tune of about 60% on average. You can't change the metal, or it's basic, inherent properties. Yes, forging helps, but forging helps steel as well, and some of the more modern steels are almost indestructible. (Reference previous post as to why Top Fuel cars use aluminum!)

[darrell cox]

The problem is not stresses form over powering steel rods or knock. Its the steel rods weights at rpm that take themselves out. This is the reason any high rpm/horsepower drag motor always ends up going aluminum. Reduce the weight of the steel rod to whats required to sustain itself and it will not handle one half the power of the aluminum rod at that same weight. Fatigue of the steel rod is greater at high rpm and high hosepower due to the steel rods total mass and weight. Its all about total output hp and total rpm. We are just outside the parameters of what steel rods can handle and have been so for sometime now. Just the weight and mass alone required of the steel rods make rod bolt selection impossible on this application. Heck H11, L19, CA625 all do not stand a chance over time trying to keep the rod from flying off the crank pin. Again its total output and rpm that once exceeded is the problem with the steel rods and its application. This is the very reason we had to switch from steel to aluminum on our 7 second Hot Rod. Once we did there was no more rod problem even at 1500hp.

[dsmlights@rage-tek]

darell where can I place the order for some aluminum rods

[mightyxwhitey53]

very good info guys...thanks for the discussion

[blksrt404]

Here is something I think it is relevant...

Here is what the page says at the bottom...

Crankshafts are both statically and dynamically balanced to counter the opposing forces created by the reciprocating assembly and to minimize vibration. Essentially opposing inertial forces must be cancelled as completely and efficiently as possible or the slide hammer effect would destroy the engine, if it were accelerated to any purposeful speed.

[darrell cox]

I have them for the 2.4s and our 2.6 and 2.8. Its only above 1000hp and 8800+ rpm where there needed. Only for drag racing and not streetable at all. Anthony and all else that fall below this mark and or steet are fine with the steel rods.

[Crazy3rdgen]

so is there a spare engine or another motor being built for mir?

[darrell cox]

No. Not enough time and customers cars are first. Kevin understands this and is still coming out with truck, trailer and Red Sled to hang out and watch some serious racing this weekend.

[Crazy3rdgen]

damn man. She did last awhile though. I'd like to see pics of the carnage. Didn't another dcr car throw the crank out the bottom? Was it the hotrod? Sounds like the sled will be even stronger next season..

sean

[tcglass1]

^ thats when crank straps came into play.

Now I have been told that the real issue with the aluminum rods is the bolts themselves, that if you kept a good eye on the stretching of the rods and the bolts and torque on the bolts you could run them for a long time with no issues?

[bayshore power]

Quote: Originally Posted by Crazy3rdgen

damn man. She did last awhile though. I'd like to see pics of the carnage. Didn't another dcr car throw the crank out the bottom? Was it the hotrod? Sounds like the sled will be even stronger next season..

sean

Next Season?
Next week or so

[DSCRACING]

Car is a BEAST!

[Specimen Kane]

Congrats Kevin!
I'd also like to add that I'd rather swap out five sets of aluminum rods for the price and performance benefit over titanium. For a race car engine like this its the way to go. I'm sure Kevins car will be even quicker after switching to the aluminum rods.

[Crazy3rdgen]

saw the motor saturday at mir, ouch!!! New rims looked good though

[bayshore power]

I will have the rods soon they will make them today