DGXR

Did a search and didn't see this posted before. Not C4-related but this is SBC. Enjoy.

dizwiz24

Need to make that standard instead of these heavy , boat anchor cranks they give us

Tom400CFI

It will barely make any difference.

Except it will sound like poo.

dizwiz24

Come on, you and I typically agree. When is taking mass out of a reciprocating assembly a bad thing?

i disagree that flat plane crank ferrari’s sound like poo.

the sound in that video was great

ChumpVette

There have been some nutty things said on this forum over the years. This has got to be in the top 5.

84 4+3

Not a huge fan of the sound either, personally think the gt350r sounds like an angry weed wacker...

And yes, aside from the cool factor it really doesn't do a damn thing powerwise. You can use headers to achieve evened pulses which about the only benefit because they tend to rattle themselves to death in larger displacements otherwise...

This guy is working on an awesome project and I did follow it a while back. It was cool.

dmaxx3500

probably an old ''smokey yunick'' trick


https://www.carthrottle.com/post/7-h...rk-of-one-man/



this guy once built a 7/8's scale 66-67 chevelle to run nascar

Tom400CFI

When the cost exceeds the benefit.

A SBC w/a flat plane sounds like a 4 cylinder. Not a Ferrari.



Yeah? Why is that? Ford themselves, stated that gains from reduced crank mass on their flat plane "Coyote" motor, were negligible.

Far greater gains could be realized for less money with an flex plate "flywheel" and a multi disk clutch,

pacoW

I believe ford built a flat crank V8 in recent years and sold a bunch.

84 4+3

And had to replace a bunch of them too. Got a couple of friends that dealt with that. Oil pump gear can fail from what I've been told...

krackenvette

LPE made a 180 degree LS engine a few years ago. Made 1100 hp

confab

So, if the flat architecture is so much better.. Why isn't everyone using it?

Surely there must be some serious drawbacks somewhere?

84 4+3

Wicked vibrations... think two I4s running at the same time.

pacoW

And I had a couple friends who spun their balancer on their LS engine, nothing to do with the configuration of the crank.

confab

So, I guess this is good is you have a peaky, freaky, little 12 cylinder with pistons the size of insulin syringes..

But not so good if you have a giant bore and great big rods?

Tom400CFI

Basically^.

Also, you could get most of the small gains that a 180 crank provides, by using 180* headers instead.

84 4+3

No it does, you build an engine that can supposedly rev that high but can't. One knocked the bearing right out of it without anything going wrong otherwise. It's great for small displacement... not so much on bigger ones.

Space387

Personally If I was building a track car I would give a flat plane crank a shot for a SBC or LS mainly for an increase in rev speed and to do something different. For a street car the tried and true cross plane we use is just fine for me. I give this guy a lot of credit for trying something most would just scoff at. To my understanding the original v8's from the 30s and 40's where mainly flat plane but the idea was droped, anyone know why? I wonder if it was to mitigate vibration or if they found torque with the change in firing pattern.

Tom400CFI

How does teh flat plane make it rev higher?

Actually, it was more like the teens and 20's -most of the very first V8's used a flat plane crank. Then, they did so b/c:
They didn't know better
It was cheaper
Virtually no cars had crank counterweights at that time anyway
All motors vibrated quite a bit.

They went to a crossplane crank b/c it balanced out w/counterweights smoothly, and the flat plane didn't.

The '32 Ford "flathead V8" had a cross plane crank -an example of a '30's, CHEAP V8 that used the cross plane, showing that it was common design feature, by then.


.

Space387

Most modern examples of a flat plane crank engine are internally balanced and require less mass providing a quicker rev (throttle response) but no higher rpm. Like I said I'd so it for the sake of doing it not to expect any marvelous gains.