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Old 05-11-2008, 06:22 PM   #18
tex1
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Default Here you go..... This was for a break in stand but....

I did find some short commings in the bench design. Being a store leads us down all roads as far as engine mounts and designs.
We changed to a pusher prop instead of the puller prop. It helps the engine build temp better.

For an in car breakin - no jumping and stay off the pipe for a couple of tanks. IE - don't let her open up.

I prime the motor with a little fuel in the carb. Open the carb about 1/4 open and set the high needle about 2 3/4 turns out. Fire her up and let her run up to 200 degrees. Use your carb opening to get your temps. Just don't run it at high RPMs! Leave it running until it gets stable and can come down smoothly to a low idle RPM and maintain its stability. OS and Sportworks motors are about 20 - 30 minutes. Nova based stuff takes 30 - 40 minutes. Let the motor go till it loosens up.
Turn it off and let it completely cool. (20 minutes) Now you are ready to harden the mechanically seated parts. Bring it back up to temp. Let it run for a couple of minutes to get to the 200+. Take it back to a low idle RPM and shut it down.
Each time the motor turns off you need to make sure it is BDC (Bottom Dead Center).

Repeat 3 more thermal cycles.

Put it in your car with a mild tune and you should be ready to go after a tank or two.

You can use the first curve in your exhaust line to read a temp off of. Match this to your head temp and you will stay closer to what is really going on inside.

Always take your motor to BDC after its run.

You should 7+ gallons out of your VSpec if it is treated right and you should always run these motors at 200+ degrees. If it seems too powerful at these settings then change your clutch.
Never detune a motor below its recommended operating temperature. You will just get shorter run times and a shorter life span.

Hope this helps,
TEX
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