DYNO Tails

[PFM]

Ok blame Mad Bill for this thread it maybe the wrong area on the forum if so sorry Don. There are some great Dyno Tails out there that would be great to share. Mad Bill just added one to another post, not all are funny but all should offer good input and better reading.

I saw a book years ago long out of print called (I believe) Dyno Tails, real life stories from a dyno shop with years of pulls. Everything from why the motor made power, why it did not, why it lit fire, why it blew the dyno mufflers to bits (how to keep it from happening again), what happens when the flywheel comes apart etc etc.

There are enough dyno folks on here to have some great tails.

Just a fun idea,

PFM

[highVE]

Well this isn't a dyno horror story from the engines standpoint, but was from mine. I was adjusting the timing on an engine we were trying to super tune for max power. Well stupid me put my hand right on top of the distributor cap to turn and wasn't paying attention. Well needless to say my arm got quite the "jolt"

Mike Theroux
www.mikesportingservice.com

[airflowdevelop]

I have sort of a problem, when in cells that exchange air well, of forgetting that the headers are HOT!

It's a miracle I still have skin.

It is common on a chassis dyno with a healthy car to get into shake, vibrate the laptop out of the passenger seat, under the car, through the rollers, then against the wall! Have to give credit to IBM for having the only laptop that survived!

Dennis

[C Stevens]

I wish I could find the picture I have, somewhere, of the dyno room at the old Howard Cams building, on South Main, in L.A. Talk about holes in the walls & ceiling.

[MadBill]

Don't want to hog the stage, but I do have a recent one of my own to relate. We had a 350 SBC race car with long side pipes on the chassis dyno last Fall and took them off for one run. Big power gain! So we figured we should try some alternative lengths, but the owner didn't want to cut up his pipes, and we couldn't afford to come back later.

Since it was a Sunday, we couldn't quickly obtain any 3 -1/2" exhaust tubing, so off to Home Depot to see what we could find. No 3 -1/2", but we scared up some 4" aluminum ducting, which we figured wouldn't melt in the necessary few seconds. We popped the seams, curled them up to 3 -1/2" and pop-riveted and hose clamped them together.

3 seconds into the run they just disintegrated! We were left with little more than a double handful of metallic confetti as a reminder of just how much energy is contained in exhaust gases...

[rooster]

On a mechanical injected smallblock, the harmonics of a 9200 RPM pull caused the idle stop to thread itself in to an idle of about 7000 RPM. Made for some frantic fumbling with a 5/32 allen wrench.

[MadBill]

On a mechanical injected smallblock, the harmonics of a 9200 RPM pull caused the idle stop to thread itself in to an idle of about 7000 RPM. Made for some frantic fumbling with a 5/32 allen wrench.

No problem, just whack on the full absorber load!

[PFM]

Mad Bill,

Never heard the bad stories about computer controlled dynos dead stopping motors at 7000 RPM, not a pretty picture.

PFM

[MadBill]

OK, how about: Ramp it up a a brisk rate, fast enough to minimize the over-rev, then with the engine dragged down to a more moderate speed, back off the idle at your (semi) leisure...

[PFM]

Unless the valve springs are really good they usually act as a rev limiter anyway, not much worse than a new driver going through the lights in third on a 4 gear car!!!!!

PFM

[putztastics]

Some guys running circle track were wondering how it would act geared deeper they were too lazy right then to change gears, so they ran a bunch of practice laps ..... in second gear!

They told me afterwards, I asked what the RPM was, I was told the driver was afraid to look, never did find out.

Customer built SBC broke a rod during a pull. We stood around in a few moments of silence (it gets quiet when that happens) finally after the shock wore off they decided to go home. The transmission was out on their Chevy pickup, so they had to drive my Dodge home!!

[MadBill]

Unless the valve springs are really good they usually act as a rev limiter anyway, not much worse than a new driver going through the lights in third on a 4 gear car!!!!!

PFM

A student in our office some years back had to get rid of his beater early seventies Chrysler V-8 at the end of work term because of the punitive cost of operating a car on campus. Instead of just junking it 'as is', he drove it to a wreckers and cut a deal with them based on a dead engine. Then he sold 50-50 tickets for $10 as to how long it would run with no oil, no coolant and a brick on the gas.
Discussion raged as to whether broken rods would prevail over seized pistons or bearings, or if valve or breaker point float would hold the revs down enough to keep it running for quite a while. Guesses ranged from 15 seconds to 5 minutes, but the ancient lump fooled everyone; it roared and clattered on for almost 13 minutes, and then just faded slowly to black...

[Unkl Ian]

I was adjusting the timing on an engine we were trying to super tune for max power. Well stupid me put my hand right on top of the distributor cap to turn and wasn't paying attention. Well needless to say my arm got quite the "jolt"

O got a similar JOLT demostrating the size of spark
produced with an MSD and big yellow Accell coil.

Insulated Pliers work fine,up to a point.
Then your arm becomes the ground.


Won't do that again.

[Nate_Taufer]

Not really a dyno story but a good friend of mine works on a sprint team and I usually go up to the local 3/10 mile track to see them race. Well a couple of races into the season the driver forgot to lock the steering wheel in place and just demolished the car on the first lap. Needless to say they always check the steering wheel

[PackardV8]

Just at the end of a hard pull, the turbo wastegate malfunctioned, boost went over 40" and there was more than 1,200 hp showing just before the pistons went away. Several just melted holes in the top or collapsed the ring lands. The most interesting one, the piston top down to below the first ring land was completely gone, but the skirt and the pin boss were still intact. None of the rods got loose.

thnx, jv.