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WJM

Oil is dissapearing...not so bad now, but driveability issues now!

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Originally posted by WJM

Thru out the whole band, i get hops and skips and detonation for no reason ever once in a while...like every 400 rpm increacement.

 

Lubricating oil is very low octane -- worse than kerosene. If you get it in the combustion chamber, enough of it alone can cause detonation. If you bring up the boost and that triggers additional blowby and blows oil into the PCV system, then a second or two after boost you might hear pinging plus see some blue smoke.

 

The 4800 RPM topout does sound like a plugged cat to me. The simple way to check is to take out the O2 sensor, lay it to one side, and drive it. If you feel a noticeable difference, then you know where the problem lies.

 

I've got access to one of those 5" WC gauge sets for checking for exhaust restrictions, its adapter screws into the O2 sensor hole, but it's just as easy to just briefly drive around with the O2 sensor out to do a quick seat-of-the-pants check.

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well, as you can see by the pics, ive installed that. It seems to be better down low...but up high its kinds...iffy, kinda unsure of its self.

 

I guess we will see during tomorrow's commute. 28 miles of high speed interstate, followed by 20 miles of intermediate driving.

 

Edit: oh, the PCV system consists of two 5/8" hoses, one from each cam case cover, teed to a single breather filter. The PCV valve plugged, and this SPFI block doesnt have the rear PCV vent, like the proper turbo/mpfi blocks have.

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those compression figures sound pretty bad, the 90-75 on the drivers side sound real low and the 90 on the passenger side is pretty bad too, but because its alone, although 110 is pretty low as well, its probably not a head gasket.

 

Assuming this is the 9.5 short block and not the 7.7 the compression ratio is kind of disheartening. sounds like its time for new rings and valves.

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Ya man your engine is toast. Knocking out cats will do nothing for that poor engine. Time for another block......maybe a 7.7:1 will last longer this time! Compression on a good engine should be within 10%

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Yeah, seems like it. Its being all wishy washy...sometimes its got power, sometimes it doest. It acts like the Vac advance is not working too...that was an all of a sudden thing since the snow got put on the ground. Adn the vac adv. is hooked up...maybe clogged? arg.

 

Anyhow, that exhaust to way too loud for this neighborhood...time to fix that other exh, and put it back on....and change tires. i dont need no sticking 175/80/13 snow/mud grippers now! Back to the 205/60/13 ultra grippy Tarmac tires!

 

I just need for it to hold together until i get the DL on the road...one more week...hold together...

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