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Search found 914 matches

by dwilliams
Fri May 15, 2020 6:02 pm
Forum: Engine Tech
Topic: Piston oil squirters in NASCAR engines
Replies: 39
Views: 3113

Re: Piston oil squirters in NASCAR engines

Older small block Chevys that had the little slot across and around one rod bolt (commonly known as the "spit hole") for oil to pass through. Various service manuals said they were for providing additional oil to the camshaft.
by dwilliams
Mon May 11, 2020 1:58 pm
Forum: Engine Tech
Topic: SBC block leaking water internally...
Replies: 11
Views: 843

Re: SBC block leaking water internally...

For a production Chevy small block, the only place I've personally seen with an internal water leak was a crack down in the lifter valley, usually in the middle unsupported area of the water jacket. Has the block you're looking at been clearanced for a stroker crank? Some water jackets go lower than...
by dwilliams
Sat Apr 25, 2020 9:15 pm
Forum: Engine Tech
Topic: +.004" o.d. Chevy rod brgs?
Replies: 4
Views: 613

Re: +.004" o.d. Chevy rod brgs?

Older Mopar V8s which might have one or more oversize lifter bores. Neither the dealer nor the local parts stores could get replacements. Probably no big thing after the internet. Oversize valve stems on small block Chevys, usually small-valve truck heads. Easy to get and in stock everywhere, they w...
by dwilliams
Sat Apr 25, 2020 9:03 pm
Forum: Engine Tech
Topic: Remember the Ford 510" budget builds?
Replies: 13
Views: 1320

Re: Remember the Ford 510" budget builds?

Historically, one of the earliest popular stroker deals was Drew Backlund's 540, which was made by using the Ford 240-6 cylinder rod and an OEM crank stroked to 4.22". I did some 460 strokers with 240 rods; apparently more than one machine or setup was used for doing the oil holes in the crank; abo...
by dwilliams
Sat Apr 25, 2020 8:51 pm
Forum: Engine Tech
Topic: Chatter marks on main bearings
Replies: 11
Views: 991

Re: Chatter marks on main bearings

That's a ground finish. The OEMs like to use something like a 10 grit wheel and feed it hard; that's where the tears come from. Depending on which factory they came from, small block Fords sometimes had broached main caps; the broach is essentially a giant file and leaves a very slight wavy finish t...
by dwilliams
Sun Apr 05, 2020 5:11 pm
Forum: Engine Tech
Topic: Another lifter to bore clearance question
Replies: 11
Views: 1076

Re: Another lifter to bore clearance question

I don't know if Ford officially changed their spec, but .0025" seemed to be normal for roller 5.0 blocks. Flat tappet blocks all seemed to be .001-.0015".
by dwilliams
Sun Apr 05, 2020 5:09 pm
Forum: Engine Tech
Topic: Mismatched 289 combo
Replies: 32
Views: 1651

Re: Mismatched 289 combo

In my experience, street 289s have performed best with cams in the 108 range for sticks or high stall converters, 110 for stockish converters. Wide lobe centers seem to just flatten the power curve with no advantage anywhere. Even if you don't change the cam, degreeing the one you have would be a go...
by dwilliams
Wed Apr 01, 2020 11:13 am
Forum: Engine Tech
Topic: Relocating oil pump pickup hole
Replies: 10
Views: 782

Re: Relocating oil pump pickup hole

Move the pickup opening to wherever it's most likely to stay in oil. For that matter, you can bend or relocate the whole pickup if that's what it takes.
by dwilliams
Mon Mar 30, 2020 7:14 pm
Forum: Engine Tech
Topic: Wrong direction on stroke
Replies: 20
Views: 1727

Re: Wrong direction on stroke

Herb Adams destroked a Pontiac 400 to 303 CID to meet SCCA class limits in the late '60s. It used a 2.84 inch Moldex crank and 7.08 inch Carrillo rods.
by dwilliams
Mon Mar 30, 2020 7:04 pm
Forum: Engine Tech
Topic: Main Bearing Oil Hole Alignment
Replies: 14
Views: 990

Re: Main Bearing Oil Hole Alignment

I always grind my oil passages over so they line up with the slots in the bearing shells, but it's more a matter of pride in workmanship than knowledge it does anything necessary. I put restrictors to the cam bearings too, usually .062 or .078. You can just drill new, smaller holes in the cam bearin...
by dwilliams
Thu Mar 26, 2020 4:29 am
Forum: Engine Tech
Topic: I am 84 YO., and building my last SBC 400 and will be over
Replies: 24
Views: 2347

Re: I am 84 YO., and building my last SBC 400 and will be over

I've listened to all the exposition about bearing speed, oil heating, frictional losses, yadda yadda, but I've also taken apart a lot of 400 cores and never noticed any unusual main bearing issues, and I freshened up many 400 and 375 dirt track motors back when useable factory blocks were still a th...
by dwilliams
Thu Mar 26, 2020 4:21 am
Forum: Engine Tech
Topic: 5 bolt SBF rear pattern blueprint
Replies: 13
Views: 985

Re: 5 bolt SBF rear pattern blueprint

Many of those dimensions were fractions... Lots of engineering and machining in the USA operated in fractional inches until WWI, when several Detroit automakers and other prime contractors petitioned the War Department to standardize on decimal inches to make dealing with subcontractors easier. Mos...
by dwilliams
Thu Mar 26, 2020 4:06 am
Forum: Engine Tech
Topic: Lash caps thickness
Replies: 8
Views: 813

Re: Lash caps thickness

That page in my notebook is dated 1996, which seems like just the other day... for 11/32 stems: .060 Bill Mitchell .080 Sig Erson .050 Chet Herbert .080 Comp Cams .060 Crane .080 Clay Smith .050 Crower .060 Lunati .060 Ultradyne .080 Norris .080 Del West .080 Manley .080 Precision Products .062 Wolv...
by dwilliams
Thu Mar 26, 2020 4:00 am
Forum: Engine Tech
Topic: aeration from scavenge pumps?
Replies: 8
Views: 597

aeration from scavenge pumps?

Does anyone have any suggestions for sizing scavenge pumps vs. pressure pumps? Most of the dry sump systems I've seen have a single pressure stage and three, four, or five scavenge stages, often the same size as the pressure stage. So the scavenge pumps are mostly churning air. Is this contributing ...