Piston I D

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RAT ROD AL

MOPAR ARCHAEOLOGIST - one parts hoard at a time!
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I have a set of Kieth Black pistons from a build a few years ago that I would like to sell but don't remember exactly what they are. Can anyone I D these from the pics. I also don't see a bore size on top like most but up inside I see 060. I do believe they are 060 but not sure. On one side by the pin they have KB 190 and on the other side there is SL 03. Thanks for any info.
 
looks like a small dome on the sparkplug side but also looks like there is a quench dome on the closed chamber side let me know I can't tell from pic
there is also a 191
if these have a quench dome and a small dome on the spark plug size they are one of several discontinued models- pity - they really worked
but you had to machine the dome to fit or adjust gasket thickness- the usual way
you can get the specs on the KB website- just click on the picture of the piston
mike the pistons for bore size
is the dome on the intake side higher than the one on the exhaust?
 
I would be interested in these if they are indeed .060 over. Are you including the rods? Floating or pressed pins? PM me if you decide to go forward. Building A 360LA for the 67 Dart. I'm in 30041. GA
Thx-
Steve
 
I would be interested in these if they are indeed .060 over. Are you including the rods? Floating or pressed pins? PM me if you decide to go forward. Building A 360LA for the 67 Dart. I'm in 30041. GA
Thx-
Steve
Yes I could include the rods and the pin is pressed in the rod. Keep a watch on this post or save me or what ever .
 
looks like a small dome on the sparkplug side but also looks like there is a quench dome on the closed chamber side let me know I can't tell from pic
there is also a 191
if these have a quench dome and a small dome on the spark plug size they are one of several discontinued models- pity - they really worked
but you had to machine the dome to fit or adjust gasket thickness- the usual way
you can get the specs on the KB website- just click on the picture of the piston
mike the pistons for bore size
is the dome on the intake side higher than the one on the exhaust?
OK here's what I checked. The dome is flat across the top. The bottom of the skirt mics at 4.080 and just under the oil ring it mics at 4.050 which sounds like .040 over bore to a chart I found. But the confusing thing is the 060 up in side the piston that has 060 in it. couldn't find much on bore size on K B site. I will look a little more. but here are some more pics
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Depending on engine brand and model, the diameter is set somewhere from 1" above the bottom of the skirt to across the pin height and will taper as you go up on the skirt.

Your readings look like 4.058 near the bottom and 4.055 up higher. So I can't see this being 4.080 but 4.060", or .060" over for a 360 piston which has a stock bore of 4.000". So that hangs together with the 060 mark under the dome, and your recollection.

FWIW, if I were building and had a stock bore engine, I would go up the minimum possible, so as to leave as much meat in the cylinder walls for future rebuilds. .060" overbore for a 360 is a substantial chunk out of the walls. The extra cubes going .060" over versus .020" or .030" is pretty trivial, unless you are racing down to the nth degree and need every smidgen.
 
OK , I dug up my old engine builders phone number and confirmed what these pistons are,with the 060 up inside on the ceiling of the piston and the 050+ on the skirts he tells me they are indeed 060 over. Shoulda just done that in the first place! Thanks guys for the responses. These will be up for sale soon after I give OLDSHOOL1979 first shot at them.
 
and those are not quench dome pistons
I'd dummy up all four corners and check clearances
also you are going to have lefts and rights so make sure the valve notches are in the right place for the heads
and the chamfers on the bearings match the crank if it has radius and the non chamfered side of the rods are next to each other and squirters - if the rods have them are pointed where they should be
 
and those are not quench dome pistons
I'd dummy up all four corners and check clearances
also you are going to have lefts and rights so make sure the valve notches are in the right place for the heads
and the chamfers on the bearings match the crank if it has radius and the non chamfered side of the rods are next to each other and squirters - if the rods have them are pointed where they should be
Thx for the info. I will check the details. These are going in a 360 LA that I'm building as a street cruiser on pump gas. The engine was built by a "pro shop" 10 years ago but never installed. PO rotated the assembly periodically and had it in a heated space. I know its +.060, rod and mains have been turned .020. Since I'm replacing the damper, flywheel, and now the rods and pistons, I plan having the assembly balanced. Using 596 heads with small valves and pretty mild cam, but will ck the clearance. The existing badger flattops calced at 8.4CR These should put me near 9.25 CR but still OK for pump gas. I'll recalc CR after I check these parts. Can always adjust some with head gasket thickness.
 
Post #8 asks the key question. If these used pistons really are 4.058" OD near the bottom of the skirt, and the Badgers for which the block was bored were .001-.002" larger, then these KB's will be too loose. KB's like this are hypereutectics and are set at a tight clearance, not the larger clearance like a forged piston would use. Most machine shops never bore 'til they have the pistons in-hand, just in case they find a variation in piston diameter.

Not trying to 'queer the deal' but hopefully you guys will work something out 'just in case' these end up a tad too small for your block's bores.
 
What heads
CC your heads and get an accurate CR B 4 ordering cam
and get your rocker geometry correct B$ ordering pushrods IDK what you are using for rockers IF HFT ot Solid and stock or Iron rockers you are OK- if roller tips then you have some spacing to do

good point NM the machine shop should be put on notice
OP check with KB and Badger and see exactly where they should be measured

If you have Iron heads 9.5 should be ok with moderate cam 9.0 with short cam and 10:1 with a big cam
although there was a recent post of lots of compression with a short 25 cam- I have no idea how he did it
also depends on weight, gearing, converter, and usage
a truck with a camper and a boat on the back or motorhome pulling a long grade has to use lower CR than a Duster 4 speed with lower gears
 
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