Technical Myths … or old wife’s tales about engines

Air is nearly 80% nitrogen to begin with. I could never see the point.

 

I call your 010 casting and raise you "all camel hump heads are fuelie heads".

 

"Timing chain jumped a tooth".

Has anyone ever seen this actually happen?

 

Yes all the time! Buick engines were famous for it. Usually wrecked some exhaust valves but not always.

 

Not actually what goes on....

 

Well…tell me about it, I’m no expert.

 

Yes. 400cid sbc, '71 Impala. Aluminum cam gear, nylon teeth. The teeth were broken off and it actually skipped. Did not run until chain & gears replaced. Dad fixed it in our driveway.

 

Yes, I've seen a good number of Chrysler products that would jump a tooth. If you advanced the timing quite a way you could get them to run. In fact that was a quick way to check for a jumped timing chain.

 

Yes, I had it happen to a F-150 at work about 10 years ago. Nobody could figure out why it wouldn’t run. It had spark and fuel, would not run. Well, says I, you have 2 out of 3. After the dimwit ran a compression test and found every cylinder even, but all way low, I said pull the cap and roll it over to number one. Timing marks on the damper lined up, but the rotor did not. New timing set and it ran like a top. It was a 302 Ford.

 

Yes....2 teeth.. volunteered to drive from Dallas to Oklahoma to pick up a cool Harley custom for one of our truck drivers. 454 4dr long bed 1974 truck...ran good going up, felt like power was dropping off, my hunch was the timing chain must have skipped, had to put in neutral at each red light and then pull into gear to not stall. Made it up there, guy and his girl friend check over bike, buy it, we load and go, we needed a push start by hand down hill...bang into gear..and go ran a few lights got to freeway...... fk fk fk..kept rpm up...made it back to Dallas ..like 2am. I kept saying if we make it, were lucky...run a few lights...make it to house.. roll up into yard and it dies, stalls out. They say ..no problem...I was holy shit we fkn made it. I told them tell truck owner pull timing cover chain is shot. They did...the nylon was chewed all to hell.

 

I question this theory. If the case is conductive enough to leak it's charge into the ground, then why wouldn't it just cross leak to the negative side of the battery through the case itself? Or installed in the chassis directly to the grounded frame? I think we're confusing "the ground"(Concrete), with the battery ground, (negative.) Power wants to flow from the positive side to the negative side of the battery, not into the earth. IMHO.

 

Installing flat top pistons (with offset wrist pins) backwards increases torque out of the corner...wth? Always a dirt track story..

 

My dad always told me it was because any slight run off/moisture on the battery ran down the sides of the battery so sitting it on wet concrete gave it a path to run from positive to negative posts. Putting it on a piece of wood allowed the wood to absorb any moisture either from the battery or the concrete basically acting like a sponge and kept the moisture from making contact side to side.

Said this was back when you actually had caps on the batteries that would allow the battery to vent.

Made since to me anyway.

.

 

Batterys should only sit on ground at junk yards, and return core piles.

Battery racks, or 2x4s what I use, does it make a difference? I don't care to find out...

 

Anyone remember the WW-2 surplus Jeeps that were packed in Cosmolene and could be bought for $50.00, but you had to buy them 10 at a time?

 

Years back there was an article on jeeps packed in crates for shipping. Some assembly required, can't remember if they found several, or just a historical pub.

 

Sorry for not reading all replies, but here is my myth: Big Blocks overheat...

 

One I heard of years ago was to make sure you always put the main caps back on when you stored a block or it sat awhile before you got back to building it otherwise the block will warp. Don't know if that's true but I always put the caps back on simply to keep from losing them. I always scratch my head when i see someone selling a block without any main caps. I could see if they were damaged but I would still try to bolt them back up just to have a complete unit regardless of condition.

 

Old-time batteries actually did go bad sitting on a concrete floor... The combination of the cold floor and the fact that the material used for the cases contained carbon black were the main culprits. The carbon black was in effect a short to ground. Not an issue in an operating, running, generating car, but sitting for long periods of time, they could drain. Or so I was told by "Old-timers". YLOBSMV (Your Line Of Bullshit May Vary)
Wait a minute.... I'm an "Old-timer" now, so you SOBs better believe ME!!

 

Nitrogen is used for 3 main reasons

1) it is more stable accross an extreme temperature range, as stated. It us also dryer so you dont get ice crystals forming.

2) it suppresses ignition. In high pressure applications, aircraft tyres, construction equipmenr etc the internal rubber section can shed rubber crumb similar to dust, this is flamable material and there have been cases of compression detonation when there is subjected to shock forces.

3) luxury car manufacturers use it becauses reduces tyre rumble noise in the car.

 

A couple more old wives tales.
1. Y-block Fords spin cam bearings...

2. Ported vacuum advance wasn't introduced until Emission Controls came along...

 

@alchemy

Hello,

My brother and I also heard that saying about flatheads. We considered a Flathead motor we saw at Reath Automotive sitting on an engine stand. It was pristine, had 3 carbs, shiny heads with chrome caps and a nice set of chrome headers leading into a larger tube with a cap. It looked good from far away and close up. But, it was a stroked and bored out Flathead that Reath Automotive was famous for back then. Oh yeah, it was also very expensive, too.

Our friends that had Flathead motors in their old cars leaked from everywhere, so there is that. We did not want a Flathead, so we opted for a SBC motor as our first build. It was fun and exciting to build the SBC motor. A giant puzzle with specific parts going in its place with precision, as taught to me by my brother.

After our second SBC motor build to a larger 292 c.i. motor with blower specific parts, we added a 671 on a new Isky-Gilmer Belt Drive and Edlebrock Manifold. It was one of the first 671 drives for a SBC motor. By the time our foray into Gas Coupes and Sedans came to a close, many months later, we opted to get involved in surfing adventures as a complete opposite of drag racing.

Jnaki

After using the Impala for our longboard transportation and getting a ton of laughs, we decided to get a simple van or station wagon for the “surf transportation” and camp outs. An underpowered Flathead motor surprised us as we put on thousands of miles without any major repairs or problems on our 40 Ford Sedan Delivery. The Flathead motor was under powered, but it was offset with no problems on the road travels and local cruising.

As compared to other hot rods and custom cruisers of my friends, I was “going my own way…” and enjoying it to the extremes, without leaks, smoking out of the tailpipe or drips on our mom’s pristine concrete floor or driveway concrete. The Flathead was underpowered as we had to downshift going up a steep Coast Highway grade and sometimes even going into first. But, it was a fact that the Flathead was one of the most reliable motors around, in our experience and part of the lore… YRMV

 

"You need a V8 coil for your SBC, that one won't work" I was told at a wreckers when I yanked a 12V coil from a 2 cyl Fiat 500 and then installed it on my 283. It ran fine for many years.
The main reason they use nitrogen in car tyres is so they can hit you for $5 per wheel to fill it up.

 

Engines run best just before they self destruct...........not true, they require human input!