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Over the past few weeks, Billgear and myself have been working on my motor. It's always been low on power so it was time to tear into it to see why. We had already messed around with timing, ignition etc to no avail. It still has great compression from the PO's rebuild and never blew smoke so we suspected something on the top end.

I had the receipts from the last rebuild and it showed a mostly stock rebuild. So I ordered a little hotter setup from Summit. Comp Magnum 270H cam kit - Comp Cams told me it's the biggest I could run without piston to valve clearance problems. Weiand Stealth intake and a Standard Abrasives head porting kit.

It took us about 5 hours to get the motor stripped to the short block. The problem was obvious as soon as we removed the front cover. The timing chain had about 3/4" slack each way and it looked like it had skipped a tooth or been installed wrong as it was about 10 degrees off!!!!! It's always run low on power in the 2 years I've owned it so this must of happened even before that and it ran!!! Low on power, but it still ran! Amazing.

Phew! I found the problem. We inspected the pistons and cleaned the short block. All looks good.

We stripped the heads down and studied them. For tomorrow, I was about to go nuts with a grinder! It took me a day to port the exhaust side and a day to port the intake side and finish the bowls. On the exhaust side we matched almost all the way out to a FelPro 1415, completely removed the valve guide, smog bumps and polished it to a shine. On the intake, we matched all the way out to a FelPro 1250 after ensuring the new intake would line up. I reduced the intake valve guide in height by about 50% and shaped the front to a point.

Bill cleaned up the valves for me and I lapped them in. After measuring the installed height on every valve we found that no shims were required. Phew! We assembled the heads and in fact, most of the engine that day. We finished assembling it yesterday. Pushed it out of the shop, added water and changed the oil. Had a fire extinguisher and hose ready!

Click, click VVVRRROOOOMMMM!!! It fired after only 1-2 seconds. Loud with a rumpety lope! Good oil pressure and a consistent water temperature through the 30 minute break in. Shut it off with glowing exhaust pipes, changed the oil and went for a spin!

HOLY COW!!!! It's like night and day, easily double the power! Above 3k it pulls like crazy! I actually had to grip the wheel with both hands and hang on!

I wonder what it will go like after installing my headers and some tuning...

Sears Point on September the 1st should be fun!

Thanks to Bill and his SWMBO for putting up with me. Thanks to my SWMBO for letting me play! And thank you for reading!
 

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Great news Shaun. So, are you saying PO "rebuilt" the engine, but didn't replace the timing chain set?

Sometimes I think "engine rebuild" to some people means new rings, and change the oil pump. /forums/images/icons/crazy.gif

Phil
 

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No kidding! I think my PO thought a rebuild was changing the oil and filter.
 

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I assume he installed all the parts on the paperwork I have. It had a stock single roller chain. I'm not aware that the engine has a huge amount of miles on it. It had 170-180 in all cylinders...

Anyway, I replaced it with a nice double roller...
 

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Shaun:
Isn't it great when all goes well? Can't wait to see it at the next cruise.

Jeff
 
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