How much OOR/Taper is too much?
Thread Starter
Joined: Jun 2014
Posts: 1,241
Likes: 47
From: Noblesville, IN
How much OOR/Taper is too much? Have a stock ls1 shortblock. I was measuring the bores last night to see how far OOR and how much taper there was. To my surprise they aren't that far off. Furthest taper I saw was right at .0005" Most of the cylinders were at least a little OOR, by anywhere from .0005" to .0015". I was hoping to keep this as budget friendly as possible and run a stock bottom end with new rings/bearings.
With this much wear on the cylinders, do I absolutely have to get them honed out or would it be safe to run? Looking to make a 450rwhp H/C/I with this. No FI, no nitrous.
I can post up a table with the measurements later after I get off work.
With this much wear on the cylinders, do I absolutely have to get them honed out or would it be safe to run? Looking to make a 450rwhp H/C/I with this. No FI, no nitrous.
I can post up a table with the measurements later after I get off work.
You can usually find info like this in the stickies...for example:
LS1/LS6 Engine Dimensions & Clearances
CYLINDER BORE:
Bore Dia.: 99.0-99.018mm / 3.897-3.898"
Bore Taper Thrust Side: 0.018mm Max. / 0.0007" Max.
Bank Angle = 45 degrees
Cylinder Bank Offset: 24.10mm / 0.949"
Also, the dimensions measured without a torque plate or cylinder heads bolted on will vary from what you would measure with them bolted on. I would think the measurements you're getting would be okay, but if you have the budget I would suggest you hone it out and use a slightly oversized piston.
LS1/LS6 Engine Dimensions & Clearances
CYLINDER BORE:
Bore Dia.: 99.0-99.018mm / 3.897-3.898"
Bore Taper Thrust Side: 0.018mm Max. / 0.0007" Max.
Bank Angle = 45 degrees
Cylinder Bank Offset: 24.10mm / 0.949"
Also, the dimensions measured without a torque plate or cylinder heads bolted on will vary from what you would measure with them bolted on. I would think the measurements you're getting would be okay, but if you have the budget I would suggest you hone it out and use a slightly oversized piston.
Thread Starter
Joined: Jun 2014
Posts: 1,241
Likes: 47
From: Noblesville, IN
Maybe I'll take the block back to the mac shop and ask them to measure it with a torque plate on. I'm not sure how much bore distortion occurs but it could be that those .0015 measurements go out a lot further.
Does piston slap usually go away with aftermarket pistons? Just curious
Does piston slap usually go away with aftermarket pistons? Just curious
Maybe I'll take the block back to the mac shop and ask them to measure it with a torque plate on. I'm not sure how much bore distortion occurs but it could be that those .0015 measurements go out a lot further.
Does piston slap usually go away with aftermarket pistons? Just curious
Does piston slap usually go away with aftermarket pistons? Just curious
Thread Starter
Joined: Jun 2014
Posts: 1,241
Likes: 47
From: Noblesville, IN
Well for everyone's reading pleasure, I'll throw the measurements I got for fun.
Measurements were taken at about an inch below the top of the cylinder, and at the bottom of the ring travel. Three measurements per, after dividing the cylinder into 3rds. Anything above zero is beyond the stock 3.898" bore.
1
Top: .0000, .0010, .0000
Bottom: .0002, .0005, .0006
2
Top: .0004, .0001, .0007
Bottom: .0010, .0005, .0005
3
Top: .002, .0009, .0013
Bottom: .0014, .0005, .0008
4
Top: .0010, .0000, .0004
Bottom: .0010, .0006, .0006
5
Top: .0006, .0003, .0000
Bottom: .0005, .0002, .0000
6
Top: .0010, .0003, .0000
Bottom: .0009, .0000, .0005
7
Top: .0008, .0000, .0000
Bottom: .0006, .0003, .0000
8
Top: .0015, .0004, .0009
Bottom: .0018, .0005, .0004
Measurements were taken at about an inch below the top of the cylinder, and at the bottom of the ring travel. Three measurements per, after dividing the cylinder into 3rds. Anything above zero is beyond the stock 3.898" bore.
1
Top: .0000, .0010, .0000
Bottom: .0002, .0005, .0006
2
Top: .0004, .0001, .0007
Bottom: .0010, .0005, .0005
3
Top: .002, .0009, .0013
Bottom: .0014, .0005, .0008
4
Top: .0010, .0000, .0004
Bottom: .0010, .0006, .0006
5
Top: .0006, .0003, .0000
Bottom: .0005, .0002, .0000
6
Top: .0010, .0003, .0000
Bottom: .0009, .0000, .0005
7
Top: .0008, .0000, .0000
Bottom: .0006, .0003, .0000
8
Top: .0015, .0004, .0009
Bottom: .0018, .0005, .0004
