Crappy running 85 GMC.

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HotRodPC

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HotRod
Truck Year
85 K20 LWB
Truck Model
Silverado
Engine Size
454 - Turbo 400 - 3.73
No. The rockers hit the cover (I think) because I really cranked down on the bolts trying to stop the leak. Since they were on backwards they were just close enough to rub holes in the cover.

If you've got a stocker cam, I don't think you could have cranked down enough to do that. Just not enough lift to make it even possible. I don't think. :shrug:

I think its funny, had a buddy once, put in a biggo cam. Then he used my tool I made for adjusting valves, which is an OEM valve cover that I cut out a strip wide enough to get on the adjusting bolts, and had a old good used neoprene rubber gasket glued down to the valve cover side. This way you don't get oil all over your good looking motor or on your headers when adjusting valves. He did all that, got it tuned. Put his valve covers on and started it up. :happy175: He had dents all in those covers. Trust me, that rocker arm isn't going to stop when it hits the valve cover in most cases. He was like, Dude WTF?? I laughed and said, DOH, time for some new taller covers. He didn't understand why it was happeneing. Sorry dude, with a 305 degree, 510 lift cam on a small block, OEM covers don't work to well. :happy175:
 

Irishman999

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Safford Arizona
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Jason
Truck Year
1985
Truck Model
K-1500 High Sierra
Engine Size
305
I have been slow in reporting about the 85 and my battles with the 305 but have some updates that made me chuckle.

One breakthrough was hooking up the PCV valve again, that made it run alot better. Still had a deadspot in the power band but the truck was running better.

I fixed some broken exhaust studs and fixed a couple leaks right after the manifold and the dead spot was gone, still did not seem to have alot of power and idle'd like total **** after it was running for a while.

One night I was messing around with the idle mixture and put some vacuum on the vacuum advance and suddenly the idle was better. I loosened the distributor and turned it all the way until the V/A was hitting on the intake manifold.

I pulled the distributor and set it one tooth forward, started it and it sounded like a completely different engine. I set the timing by ear and adjusted the idle screws again and......

This thing seriously runs so crisp and perfect its unbelievable. At idle you cant hear it running, you could set a glass of water on the dash and not even see a ripple. I am averaging between 13 to 15 mpg and its running slightly fat, I am pretty sure changing to the original metering rods and messing with jets could get me above 16 mpg.

Almost forgot to mention that last time I set the timing I used a timing light, so maybe my Harmonic balancer spun or some ****.
 

HotRodPC

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HotRod
Truck Year
85 K20 LWB
Truck Model
Silverado
Engine Size
454 - Turbo 400 - 3.73
Cool, so its still doing good.
 

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