What Revs

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Derek
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What Revs

Post by Derek »

What should a 440 rev to without doing any damage, just lately mine gets to about 4500rpm and then starts to hold back, I've tried new plugs, leads,
cap, rotar arm, dis cap, I've even tried Alan's 750 Holley (black 68 charger r/t) but still the same. :cry:
Are we there yet dad ..... 10 to the gallon but worth it.

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Dave-R
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Post by Dave-R »

6500rpm is considered the safe absolute max for a 440.

What it will run to in practice depends on a lot of factors such as condition of engine, cam, carb, timing etc.

You tried a carb but what cam and dizzy timing are you using? How worn are the cylinders? When did it last have a de-coke?

4500rpm is really low even for a stock motor.

NEVER try to rev an engine over 4000rpm when not actually driving. It is VERY bad for them.
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Derek
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Post by Derek »

Dave, Engine condition is ok, I did a compression test and all cylinders are between 150psi-160psi .

The cam that was fitted a few years back is a Purple Shaft 0.474 lift
280 degree duration, 60 degree overlap, the cam timing was set when fitted and has not been toughed since.

The distributor timing is set at 17int 36 total

I did a de-coke last year when I took the heads off to do the valve stem oil seals.

The carb is a 750 Holley about 5 years old and done about 8,000 miles.

Last year I fitted a Crane Fireball XR700 points conversion ignition,
do you know if these are any good.

Do you think that it's worth puting the points back in and trying that.


Any help and advice would be very welcome.
Are we there yet dad ..... 10 to the gallon but worth it.

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Derek
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Post by Derek »

Engine details
Are we there yet dad ..... 10 to the gallon but worth it.

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Derek
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Post by Derek »

Steve
I've not realy taken the revs that high since last years nats, it was only at this years, that I noticed that it had lost some of its go.

The best time was 15.610 and that was a struggle. I gave up after two runs, It just doesn't want to go over 4500rmp
Are we there yet dad ..... 10 to the gallon but worth it.

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Dave-R
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Post by Dave-R »

Maybe faulty ignition system or ignition leads?
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Post by latil »

Oldest 1 in the book this are you getting full pedal travel? Cable adjustment not slipped or carpet bunched under pedal?
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