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flattie
12-13-2004, 06:53 PM
Well I pulled my engine apart to have it freshend up for the next summer. When I pulled the timing chain cover off I found the timing marks on my Pete Jackson gear drive to be 1 gear off at top dead center. Not sure if its retarded or advanced I didnt look at it that close. It looks to have a zero deg bushing on the cam running it straight up. So I brought it over to the local engine builder who put the short block together this morning to have Him degree the cam before he takes it apart. What I want to know is how did this engine run so good like this? It idled down to 900 rpm and seen rpm around 6500 rpm I would also like to mention this is a blown 468.

ColeTR1
12-13-2004, 07:38 PM
I pulled the timing chain cover off I found the timing marks on my Pete Jackson gear drive to be 1 gear off at top dead center.
WOW I’m surprise your valves didn’t say hello to the top of your pistons. Have you taken the heads off yet?

flattie
12-13-2004, 07:43 PM
Yes the heads are off. Very little carbon on the pistons and light tan on the valves on the heads. Nothing could collide because its a low comp. delio I think

ColeTR1
12-13-2004, 10:51 PM
Nothing could collide because its a low comp. delio I think
Having the blower on there would hide the cam-timing problem. It will run a lot stronger with it right!! I think you got lucky!! Your cam must not be that big and the low compression saved you some $$$$.

flattie
12-15-2004, 08:13 AM
Well I just got back from the engine builder and the the cam was off the cam card said 108 deg lobe center and it was 123 degrees meaning the cam was retarded. This now explains why when I was timing the engine it always wanted to idle better with more than 34 degrees ignition timing in it. But I never went over due to having a blower on it. Now do you think I will se a world of differance on performance? That is 15 degrees differance

Squirtin Thunder
12-15-2004, 09:24 AM
Basically your telling me it is 7.5 deg retarded. You will get a higher top end that way. If you move it to strieght up you will have more low end power. If it were me I would split the difference; 3.5* - 4*. That is just me !!!
You can call anytime
Jim

Infomaniac
12-15-2004, 12:33 PM
Well I just got back from the engine builder and the the cam was off the cam card said 108 deg lobe center and it was 123 degrees meaning the cam was retarded. This now explains why when I was timing the engine it always wanted to idle better with more than 34 degrees ignition timing in it. But I never went over due to having a blower on it. Now do you think I will se a world of differance on performance? That is 15 degrees differance
If it's not too late have him check valve open and close @.050 and compare to the cam card. Instead of lobe centerline method.

Squirtin Thunder
12-15-2004, 01:02 PM
Well I just got back from the engine builder and the the cam was off the cam card said 108 deg lobe center and it was 123 degrees meaning the cam was retarded. This now explains why when I was timing the engine it always wanted to idle better with more than 34 degrees ignition timing in it. But I never went over due to having a blower on it. Now do you think I will se a world of differance on performance? That is 15 degrees differance
Can you scann and post your Cam card ????