216 rpm

[motorhead52]

What is the max rpm the 216 can rev to. Some one told me 3500 rpm and above would blow the engine. My truck is a 52 chev 216 motor, three in tree, all origanal. In the process of rebuilding the engine and never drivin anything with out a v8 in it. Thanks

 

[vwnate1]

RE: 216 / 235 Safe rpm

?? your handle is the same as a moto buddy of mine is ..

Anyway , it's not so much " blow up the engine " as it is that the connecting rods have a weak design and will stretch when subjected to sustained high RPM's and will eventually break right below the wrist pin ruining not only your day but the engine block most of the time too .

Many 216 engines are loose on the bottom end and so will easily Bzzzz down the highway @ 60 ~ 75 MPH but the bottom end of the connecting rod usually gives up in a few thousand miles as the oiling system isn't up to the job plus it being a long stroke 1930's design engine it was never made for hight speed operation even though it'll easily accellerate to those speeds .

So , the high speed question is this : will it toss a rod bearing or break off first ? .

If it tosses a rod and you shut it down PDQ there's a real chance you can tow it home and change the connecting rod engine in situ , no need to remove the cylinder head if you're carefull , shim it up just so and you're good to go again .

Good luck and try to keep it at or below 3,000 RPM's on the open road .


-Nate

 

[motorhead52]

RE: 216 / 235 Safe rpm

Thanks Nate. Was going to drop a v8 in it but with gas prices and also dicovered the block matches the vin tag so it will be worth more if i keep it mostly stock. So this striaght 6 is new to me.

 

[ttcodi]

RE: 216 / 235 Safe rpm

farts travel up your SPIN. . .or your SPINE?

 

[coilover]

RE: 216 / 235 Safe rpm

I measured the heigth of a 650X16 tire and it was 28 1/2 inches. Took my shoes and socks off to do some serious calculation and came up with 72 mph at 3500 rpm. I never knew of a 216 that could take that for a sustained period. A rule of thumb with a 4.11 gear is your speed will be double your tach reading in hundreds. In other words 35 Hundred rpm will be 70 mph, 25 hundred rpm will be 50 mph, and 3000 rpm (30 hundred) will be 60 mph. Conversely, your speed divided in half will be very close to the engine rpm. This would mean 3000 rpm would be probably the highest the old babbit buster would be comfortable with. Tires that are way taller or shorter would change this. In my misguided youth I had several 216's that were humming along very well till I was introduced to a split manifold and Smitty mufflers. They're lifetime was greatly shortened after that and high revving was the culprit, but I did learn about shims and even rod cap filing.

 

[vwnate1]

RE: 216 / 235 Safe rpm

Evan ;

3,200 RPM's is about the fastest you want to keep it at , I was clocked at slightly over 75 fully loaded up and with three people squeezed in the cab going across Death Valley once....

-Nate

 

[coilover]

RE: 216 / 235 Safe rpm

Dang, Nate, I hope you have some a/c in the ole 49 or make that trip at night. The guy in the middle was pretty toasty if not. Now we know why you really promote sealing and insulating.

 

[vwnate1]

RE: Desert Operation

Yeah , it was SWMBO in the middle , she was very good about it .

I love the desert and Death Valley best of all ~ the heat usually stays below 125* since I don't go there in summer . no AC on this rig , none of my vehicles has better than 2/60 AC , it always works .

That's why I push so hard for electric fans too , they're more efficient and less power drag .

-Nate

 

[myascape]

RE: Desert Operation

You ought to try a desert crossing in an armored Humvee in the dead of Iraq's summer! Yeeeeeeowwwch! Hot.

My hummers don't have a/c. Bummer.

 

[vwnate1]

RE: Desert Operation

Just for shoots & giggles I climbed into a Humvee once , what a tight fit ~ I have short legs too .

I cannot imagine why anyone would want one . we had a '52 M38A Jeep when I was young , that was loads of fun and plenty roomy for such a small vehicle .

Iraq ? no thanx , I'm busy dodging bullets here in South Central L.A.
~ at least we have good tunes on the radio here

-Nate