[455rebel]

Originally Posted by STEELCITYFIREBIRD

Run the tank down and put a few gallons of 100+ octane fuel to it, that would be very telling.
Verify you don't have a wrist pin or rod bearing knock. Valve train noise? The Summchit lifters are just that. Bottleneck studs? You may not need to adjust, just torque and go. TBD
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Think about under what conditions does it knock.
Where is the temp running, and where does it go when it knocks, if anywhere.
Does it run on when you shut it down hot?

It had a cam lobe, and an "ATF oil treatment" in it's diet not to long ago.
Base engine needs to be evaluated and considered.
Do you have blow-by from the crankcase with the PCV valve line capped and removed,with engine hot, held revved @ 2500RPM for at least a minute, from the oil fill cap?
150psi on ALL cylinders?

Honestly, any oil smoke from the exhaust?
>@ start up or on hard accel
>engine braking decel
>Any evidence of oil on the plugs
Any oil burning in the chambers will aid and abet detonation.

This is an 80K motor with a re-ring job. The condition of the guides, valve seals and ring sealing may be suspect...above and beyond the cam choice.

Were the rings file fit rings for std bore 455, or .010"+ rings you file fit?
Ridge ream, makes me cringe. If their is a lot of taper in the cylinders, your rings may have lost their tension prematurely, a leak down test is where I would be @ myself. Maybe even just an air hose connected to the compression tester if it has a quick disconnect.

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Garbage in , garbage out.
Let's get all the facts.

Flat top or dished pistons? Your looking @ a big swing in compression ratio.

So you have........ 6x-4 heads,cut .020", factory deck height, .040" head gaskets, stock valve springs, no shims, no valve job in your ownership.
----PREVIOUS CAM----
Lunati 10510703
Advertised Duration (Int/Exh): 268/276
Duration @ .050 (Int/Exh): 227/233
Gross Valve Lift (Int/Exh): .489/.504
LSA/ICL: 110/106

----CURRENT CAM---
2801 Summit
Adv Dur : 288/298
Dur .050 : 214/224
Valve Lift : 0.444/0.466
Lobe Separation (degrees): 112

Correct?

Hope it all comes together for you.... on the cheap!

Previous cam was a 702 not 703
On very cold mornings I have piston knock for a few min till it warms some.
I have a 195 stat in so it will heat in winter(same as I have ran since engine install)
It ratteled or ping when up to temp , light to part throttle, when climbing hills, in high gear at25-40mph.
I've drove it 1500-2000miles since cam install.
Changed oil twice, filter 4 times, oil never got black.
No blowby. Added about. 1/4 qt in 2000miles.
No smoke. And I've hammered on it a lot!
Pcv works and no oil in line.
Only measured comp on 2 cyls each side, 1,3,2,4.
Plugs look clean, well orangeish from the 104 boost I added.
Valve job done on 400 Heads before install, and Teflon seals on intake guides..
Rings were 10 over and filed to fit.
Wasn't much ridge to cut out.
Dingleberry hone.
The pistons were dished, but according to post hear pontiac didn't use dish pistons.
Comp cam springs, speced for the 702 Cam.
Comp roller tip rockers.
Poly lock adjustable lock nuts.
Factory push rod guides.
As stated before with 702 cam it pulled off idle to 5100rpm.
It would run ocasonally on 87.
Inital at 15-16btdc. Man vac on crane advance can.
Putting it back together today. Will post comp after together.
I will test drive it at initial 8btdc then sneak it back up till it pings or till I get to 14-16 btdc.
Then I'll go back to softer dist springs till I get ping then back down.
Thanks all.