What's bthe difference 351W

[Fellro]

The angles are true, but their effects are the dispute. There is some force sideways, but perhaps not enough to cause wear.

 

[dragogt]

Right, thats why gm, honda, and others have more severe r/s angle's than the ford that everyone cries about, and we see how long they live.. jmho

 

[Fellro]

I'm not arguing, simply stating a fact that there is force in the sideways direction, not saying a thing about it actually causing problems. Take a class in statics and dynamics and you will know what I refer. The majority of the force will be in the direction parallel to the cylinder, but there will be some also perpendicular to the cylinder wall. Without having figures to run, I can't say how much in comparison. Just stating the physics of the situation.

There is a piston rock condition that plagues the IC motors too... Seen more than a few pistons shatter from this condition, and is also why we have to check for out of round conditions when checking the block. Maintenance and oil quality figure in even more.

 

[dragogt]

Gotcha, I see what your saying.

 

[Truckin4life]

Hell, run a 500 shot a NNNNNAAAAAAAAWWWWWWWWWSSSSSSSS through em all and see what motor will still run, which ever one does, i choose it!

 

[Dirky]

Kinda off topic, but I have a friend running a 400 H.P shot of nitrous on his 67 F-100 with a 351W. Stock internals/heads. Runs a couple of times a year at the drags, hasn't blown up yet.

 

[Alvin in AZ]

Sorry, but "rod angles" have been proven to be a myth..

Proven to you but not to me.

Maybe it's been "proven" to have been over blown in the past?
The rod length -has to have some effect-. Take the rod lengths
to the -absolute extremes- and see what effect it has.

Just disputing the idea that it's "been proven to be a myth" is all.
Maybe it can be shown that typical rod lengths has next to no
effect, but "next to" is the key there. Just how "next to" is it?

Smokey Yunick had good reasons to say...
"stuff the longest rods you can into your engine"
A lot of that had to do with high RPM engines he was building.

Me, if I had my way, my torquer-engine would have shorter rods.
But like Conanski pointed out to me one time tho, shorter rods are
low on any list of what effects an engine's torque band.

Ok, so, if-or-when I build my 393w, it'll have stock length rods not
the 1/4" longer rods the racers want just because I'm weird and
I'm the one payin' for it.

Alvin in AZ

 

[dragogt]

Will a long rod 302 make more power than a "stock" rod 302 set up the same Sure No arguments fro me on that on..

What I was more referring to was the "347 has bad rod angles" myth.

Is the long rod worth the extra cash??? Byers choice. jmho

 

[1985 Ford F-150]

I thought it was longer rod=more torque and short rod=higher rpms.

 

[dragogt]

Set up right, it will do both..

 

[conanski]

I thought it was longer rod=more torque and short rod=higher rpms.

For any particular engine variations in the rod length makes a relatively small difference, small relative to every other parameter like compression ratio, cam spec, and head flow. A longer rod holds the piston at TDC slightly longer building more pressure and therefore making more TQ. But you can't directly compare the rod length in 300 I6 to a 302 V8 for example because the engines formats are totally different. The reason the I6 is known as a torquey motor has more to do with the cam and heads than it's stroke length, put a longer duration cam in and it would have a peaky powerband similar to the 302..though it still wouldn't be identical because it's a 6cyl not a V8.
In racing the class tightly restricts almost every parameter of an engine, you can only have 357 cu/in, must use X head with Y valves and springs, must use ABC cam, R intake and Z carb. One of the few variables left is engine bore and stroke so if you choose a combo that makes more TQ from the exact same displacement then you have an advantage. But on a street vehicle you have no such restrictions and since better heads and larger cams will produce much greater gains there's really no point even considering using any rod/piston combo other than what your motor already has or whatever a stroker kit supplies.

 

[flareside_thunder]

Subscribing.......

 

[Alvin in AZ]

I thought it was longer rod=more torque and short rod=higher rpms.

Like Conanski posted, Smokey too thought both was better with longer rods.

It's the torque-band that's slightly effected according to what I read and
their explanation of it sounded good to me. {shrug}

The torque band (if it really is effected? is supposed to be effected just
above idle, but I have never seen a torque-rating-graph cover that RPM.

My way of thinking on this is, the shorter rods would actually negatively
effect upper RPMs. No sweat here, I couldn't care less about anything
above 3500 RPMs.

My plans aren't etched in stone on this, it's a year off maybe.
A lot depends on how well my '91 to "A9L MAF" conversion goes.
Working like crazy getting the dangged-thang ready for a test drive. LOL

Alvin in AZ
http://www.panix.com/~alvinj/file12/BroncoYd.jpg