I realize by searching that most 2056 builders dont have any problem touching the redline on the Tach for a few secs. If thats o.k. to do, where should the red line be placed. On my stock gauge its at 5600rpm.

Where would you put the line on your 2056. and if that is where you would put it, would you ever touch it even for a second??


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That's a question that can't be answered without knowing what the cam specs are, piston to valve clearance, and valve springs ratings. . . and then engine balance needs to be right. . .
so the smart ass answer is 100 rpms less than when the valves float. .

If you have a stock cam and heads it will not change.

If you have a stock valve train, the redline should be the same.

9550 cam and valve train kit
96mm kb pistons
stock rebuilt rods
stock flywheel (resurfaced)
stock heads rebuilt by Ham inc.
swivel foot adjusters
D-jetronic


no idea on measurement of valve to piston clearence, I would need to ask Tony tommorow.


Just give me an idea. The line does move, how do you figure out how far, and the big question... is ; is it o.k. to touch it?

That valve train kit is designed for a max of 6,250 RPM. You are not making power anywhere near 6K with the 9550 cam.

Redline would be 6K if it were mine.

Thanks




p.s.
The engine was completly torn down since "the incident". I took your advise. Hopefully will be finished by the end of the week.

and what did you find?

So, please jump in if I'm wrong, but isn't there more to determining red line than cam and valve train? Certainly valve float will be an upper limit to making power, and depending on geometries, could result in a valve meeting a piston crown which would be bad. But, don't forget about the bottom end In particular the rods. They need to be able to hold up to the inertial changes. When you cross beyond that limit, you've exceeded the red line and it gets real exciting when the case gets ventilated by a rod. Exceeding this limit slightly causes damage not immediately visible, exceeding it by a lot cause very visible damage.

to me, it's not about how high you can rap it. . it's about where the engine produces torque and where it falls off. . . taking the engine higher than that is really counterproductive, shift up and get the engine back in the torque band. Put it on a dyno is the only way to really measure what is going on at the rear wheels. .

+1


Not a good idea to push a street engine to within 100rpm's of valve float on a regular basis. That close to float the springs are already seeing undo stress.

Keep in mind that the max rpm that springs are capable of valve control will slowly decrease as the springs age & fatigue, so the red-line will slowly drop too. The set-up Joe has with Jake's cam and my head parts is capable of handling 6250 and perhaps a bit more when fresh. But taking it to 6150 between every shift will shorten the life of the springs for no good reason.

Spin it until it blows up, then back it off a hair!

--DD

Don't be a pussy, drive that bitch hard just like The Shoe does!

The valve train is what limits rev ranges with these engines more than anything.
The effective mass of all the components, spring pressure and ramp speed of the cam are the main ingredients. I developed te 9550 and all of the pieces in this valve train kit and know that lifting begins at 6,250 RPM when using these components of the shelf.

That said, this can when coupled to stock heads (what it is optimized with) will barely pull to 6,250 RPM.

I guess your asking about a specific engine and cam combo but as a point of discussion I would start with the connecting rod ratio and think in terms of harmonics. Crank stroke/rod length piston speed and wieght. Then when you factor in what your intent is for the engine you can protect your lower end by cam size/production and cylinder head air flow. You can't build the top end of an engine to exceed the limits of the connecting rod ratio. Well, I guess you could.. I'm not the smartest engine guy here. We have some really big brains that contribute here but I always tried think in these terms with my BB Chevy drag engines and my BMW engine builds.