1997 gmc k2500 burban

Christian Steffen

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Power Steering hoses and decided on timing chain/water pump. Trying to check for slack looked like about 10* before pulling things apart. Loosening the oil pan is a major pain. With new timing set 2* of slack movement. New timing set is a couple of degrees different from the original.
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I commend you for doing a timing chain with the engine in.. that looks like a PITA! So you did end up replacing the timing set then? IIRC the retard was all in the gear? Just checking because i can't remember for sure lol

Also, maybe i missed it but what are the plans for the 489?
 

yevgenievich

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I commend you for doing a timing chain with the engine in.. that looks like a PITA! So you did end up replacing the timing set then? IIRC the retard was all in the gear? Just checking because i can't remember for sure lol

Also, maybe i missed it but what are the plans for the 489?
Initially I thought stock replacement timing set would be same as gm, but it appears the cam gear is 6* or 8* different from stock. Hoping it will run better on the road. Other motor is in the machine shop taking more time than it should. Waiting on piston selection confirmation so I can order heads(brodix race rite oval ports) and this is current proposed cam spec:

233/233 @.050"
.353"/.353" Lobe Lift
.600"/.600" Valve Lift
114 LSA

Specific cam core I was looking for is expected to be available in September
 

yevgenievich

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Initially worked well, even had the crank retard thing in spec. Had to run it very hard today and eventually motor died. Trans also threw input vss and gear ratio codes at me
 
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