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Discussion Starter #1
This was fun. Engine was built for a friend when I worked in a machine shop in 1989. 1975 C30 pickup with an original 454 spun a rod bearing when run low on oil. Build was as follows:

Badger cast flat top pistons, 0.060 over, no torque plate
crank machined undersized 0.010 mains, 0.020 rods
rods resized with ARP bolts
Sealed Power plasma moly ductile top ring set
781 heads, K-line guides, hard exhaust seat inserts, PEP SS valves, Isky 805-DO springs 130 lbs seat
Delta regrind Comp Cams 268H, white box lifters
Comp Cams 1.72 Magnum roller tip rockers, stock 3/8 pushrods
Melling M77HV with 70 psi spring
Performer 2.0 intake with Holley 3310, stock jetting
Victor gasket set

Truck was daily driver for first 15 years and occasionally used to haul 10-foot camper and tow a boat. Always had plenty of power. Last years in service it consumed about a quart of oil every 300 Miles. Valvoline VR1 20w-50 was used exclusively until 2015 when I acquired the truck. I used 10w-30 thereafter

Upon disassembly engine was super clean inside due to frequent oil changes
Many of the valve tips had the star pattern indicative of valve float. Others had about 0.110” wide pattern from the roller tip rocker. Note that in a recent build I found this Comp rocker needed 0.200 longer pushrods for minimal sweep
Umbrella valve seals were mostly completely gone and in the oil pan
Springs measured 95-105 lbs seat, 250-260 lbs at .500 lift
Exh guide clearance was around 0.0012 at top and 0.0025-0.003 at bottom
Int guide clearance was around 0.0025 at top and 0.002-0.0025 at bottom. Except two measured about 0.006 at top
SS valves had negligible stem wear
Pistons looked good, no collapsed skirts. 0.0025 top ring land clearance, 0.0015 2nd
Pistons about 0.040 below deck at TDC
Negligible bore wear. Clearance measured 0.002” at top of bore above the top ring and 0.0025 for the rest of the bore
Visible scoring in every bore, parallel to bore on cam tunnel side. Can only feel scoring in one bore
Rod and main bearings were all flaking and rough to the touch. No copper shown. Crank looks great
Cam looks great. lifter bottoms look like a mirror surface with no pitting

I expected worse, and was particularly surprised with the minimal bore and cam/lifter wear. Plans include thorough cleaning, torque plate hone, deck 0.020, polish crank and reassemble With new rings, bearings, etc. I’ll swap the 781’s with a fresh set of 236 peanut ports.
 

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Cool thread!
Same cam lifters again?
 

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Discussion Starter #5
I am planning to reuse cam and lifters. Cam looks great. Lobes still have taper All the lifters were spinning.

I do think most of the oil consumption was lack of valve seals. None of the carbon was washed away from the top of the piston edges. Pistons were dry above the second rings. only about half of the face of the second ring was shiny. The oil rings were clean and move freely.
 

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It’s also worth mentioning the 100k mile Comp Cams roller tip rockers look great. I haven’t decided whether to reuse them with the right length pushrods, or a set of ZZ502 stamped rockers I have.
 

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Thanks for talking the time to post your findings and all the measurements. Nothing beats before/after data to verify what lasts/works and what doesn’t.
Do you recall what type material crank/rod bearings were used?
Oh ya, so much for the Valvoline bashers!! 20/50 kept this combination supreme!
 

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Question on the cam - "Delta regrind comp 268H". Are you saying that Delta has the comp 268H lobe profiles and ground them on another core? Just curious for the reason for the "regrind" vs just running the Comp cam. Just economics, or some other reason?
 

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It’s also worth mentioning the 100k mile Comp Cams roller tip rockers look great. I haven’t decided whether to reuse them with the right length pushrods, or a set of ZZ502 stamped rockers I have.
Unless I was hindered by a rule book, I would never use stamped steel rockers on an old school BBC or SBC. Valvetrain stability and accuracy should be high on the list of necessities.
 

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Oh, I dont know, for a 5000 rpm peanut port mill, they'd be fine.

Cool thread , thanks for sharing!
 

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Discussion Starter #11
Thanks for talking the time to post your findings and all the measurements. Nothing beats before/after data to verify what lasts/works and what doesn’t.
Do you recall what type material crank/rod bearings were used?
Oh ya, so much for the Valvoline bashers!! 20/50 kept this combination supreme!
Bearings were Federal Mogul stock replacement sold by the NAPA store. I've always liked the valvoline racing oil.
 

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Question on the cam - "Delta regrind comp 268H". Are you saying that Delta has the comp 268H lobe profiles and ground them on another core? Just curious for the reason for the "regrind" vs just running the Comp cam. Just economics, or some other reason?
The owner at the time was a Studebaker hotrodder. New cams weren’t available. He figured if a regrind was good enough for his Stude it was good enough for his shop truck.

I think the cam survived due to good oil and 1989 vintage lifters. I do wonder at what mileage the springs began going away?
 

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Unless I was hindered by a rule book, I would never use stamped steel rockers on an old school BBC or SBC. Valvetrain stability and accuracy should be high on the list of necessities.
To each his own I suppose. Mark Jones ran stamped rockers to 6,400 rpm on a peanut port BBC that ran 10’s in his’68 Chevelle. Seemed to run just fine.
 

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To each his own I suppose. Mark Jones ran stamped rockers to 6,400 rpm on a peanut port BBC that ran 10’s in his’68 Chevelle. Seemed to run just fine.
A lot of people run peanut port headed BBC's and make like 150 hp less than what Mark can get. Not many can do what he does.
 

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Bearings were Federal Mogul stock replacement sold by the NAPA store. I've always liked the valvoline racing oil.
Was they alu or tri-metal?
 
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