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Crank Measuring part 2 #207236 01/28/09 10:08 PM 01/28/09 10:08 PM
Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again Moparnut426 OP I Live Here
Moparnut426 OP I Live Here Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again	So I asked about plastiguage earlier, wasnt really happy with my measurments as far a s accurate. So, i used a mic, my crank measures at 2.125 pretty much on the dot. K1 stuff is nice, I dont have an inside mic so I measured them with my digital dial calipers whick I tested with my mic, and its spot on, I had it calibrated erlier this year at a machining shop in town. The rods measure 2.250 without a bearing in it, and each bearing half measures .062. If I add the .062 together it makes .124, that added to my inside measurement of 2.250 makes 2.374, now take that measurement minus the 2.125 i end up with .249. Is this more accurate than plastiguage because I hit .25 almost on the nut. Its a lot of math, and a bit of hassle, but without a dial bore gage its all I have for now. Would you guys consider this an accurate enough measurement, and run it or should I buy a dial bore gage? or is my math totally messed up? I am not known for my math skills so Im just asking it this will work, dont rake me over the coals if Im wrong. Kasey

Re: Crank Measuring part 2 [Re: Moparnut426] #207237 01/28/09 10:11 PM 01/28/09 10:11 PM
Joined: Jan 2003 Posts: 4,616 Kissimmee Fl. D dusturbd340W5 master
dusturbd340W5 master D Joined: Jan 2003 Posts: 4,616 Kissimmee Fl.	I will bet that every one will say get a bore gauge the way you are doing it has to much chance of measurements stacking up. 70 duster full chassis super pro 416 CNC Indybrock heads 727 w/brake best so far 1.212 60 6.219 in 1/8 at 110.88 9.768 at 137.81 1/4

Re: Crank Measuring part 2 [Re: dusturbd340W5] #207238 01/28/09 10:14 PM 01/28/09 10:14 PM
Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again Moparnut426 OP I Live Here
Moparnut426 OP I Live Here Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again	Kinda what I thought too, but all my measurements were very to the number, and not to an odd decimal. We will see.

Re: Crank Measuring part 2 [Re: Moparnut426] #207239 01/28/09 10:21 PM 01/28/09 10:21 PM
Joined: Jan 2003 Posts: 1,633 Jacksonville, NC RonP top fuel
RonP top fuel Joined: Jan 2003 Posts: 1,633 Jacksonville, NC	Quote: So I asked about plastiguage earlier, wasnt really happy with my measurments as far a s accurate. So, i used a mic, my crank measures at 2.125 pretty much on the dot. K1 stuff is nice, I dont have an inside mic so I measured them with my digital dial calipers whick I tested with my mic, and its spot on, I had it calibrated erlier this year at a machining shop in town. The rods measure 2.250 without a bearing in it, and each bearing half measures .062. If I add the .062 together it makes .124, that added to my inside measurement of 2.250 makes 2.374, now take that measurement minus the 2.125 i end up with .249. Is this more accurate than plastiguage because I hit .25 almost on the nut. Its a lot of math, and a bit of hassle, but without a dial bore gage its all I have for now. Would you guys consider this an accurate enough measurement, and run it or should I buy a dial bore gage? or is my math totally messed up? I am not known for my math skills so Im just asking it this will work, dont rake me over the coals if Im wrong. Kasey Your math is wrong Crank 2.125 Rod big end 2.250 bearings .062 + .062=.124 SHould be Rod 2.250 - .124 = 2.126 Rod 2.126(with bearings in) - Crank 2.125 = .001 clearance Last edited by RonP; 01/28/09 10:22 PM.

Re: Crank Measuring part 2 [Re: Moparnut426] #207240 01/28/09 10:22 PM 01/28/09 10:22 PM
Joined: Apr 2004 Posts: 1,981 SE Michigan TS3303 top fuel
TS3303 top fuel Joined: Apr 2004 Posts: 1,981 SE Michigan	yes your math is screwed up. I doubt you have .25 clearance with plastiguage, check your decimals. The rod bearing makes the bore smaller not bigger, subtract the bearing thickness from the bore. 2.250 - 0.124 is 2.126 which would give you .001 clearance. Those numbers are no where near accurate enough. You need the tools to measure accurately to 1/10's (.0001) for them to have any value.

Re: Crank Measuring part 2 [Re: RonP] #207241 01/28/09 10:23 PM 01/28/09 10:23 PM
Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again Moparnut426 OP I Live Here
Moparnut426 OP I Live Here Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again	Ok, my math has always sucked. With the plastiguage it was dead on .002. Ill get a dial bore gage coming tomarrow.

Re: Crank Measuring part 2 [Re: Moparnut426] #207242 01/28/09 10:25 PM 01/28/09 10:25 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Put the bearings in and torque them down and TRY to get a reading with your calipers(should use a bore gauge)subtract the crank numbers from the bearing ID. Or take the block, crank and your rods to your local machine shop and have them measure it(which this would be better)

Re: Crank Measuring part 2 [Re: MR_P_BODY] #207243 01/28/09 10:34 PM 01/28/09 10:34 PM
Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again Moparnut426 OP I Live Here
Moparnut426 OP I Live Here Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again	I planned on doing that when I take the whole thing to the machine shop to get ballenced, I like doing things my self as I love to learn. I have taken many engine machining classes, and I have resized rods, and bored blocks, but I used the schools "correct" tools. I havent touched any engine machining tools or equipment in 9 years so Im a little rusty. Im having Kecks machine do the block work and balencing.

Re: Crank Measuring part 2 [Re: MR_P_BODY] #207244 01/28/09 10:35 PM 01/28/09 10:35 PM
Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again Moparnut426 OP I Live Here
Moparnut426 OP I Live Here Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again	Quote: Put the bearings in and torque them down and TRY to get a reading with your calipers(should use a bore gauge)subtract the crank numbers from the bearing ID. Or take the block, crank and your rods to your local machine shop and have them measure it(which this would be better) Also I didnt want to put the bearings in the rods because my caliper is pretty sharp and I didnt want to knick up the bearings. I have a bore gage coming from Ebay. Thanks guys!!

Re: Crank Measuring part 2 [Re: Moparnut426] #207245 01/28/09 10:44 PM 01/28/09 10:44 PM
Joined: Jan 2003 Posts: 32,394 Q Quicktree I Win
Quicktree I Win Q Joined: Jan 2003 Posts: 32,394	I would take it to a machine shop and have them check it before buying those tools for a 1 time deal.

Re: Crank Measuring part 2 [Re: Quicktree] #207246 01/28/09 10:48 PM 01/28/09 10:48 PM
Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again Moparnut426 OP I Live Here
Moparnut426 OP I Live Here Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again	Well I have needed them for more than this engine, I have built a lot of engines and wanted more accuracy. I have always relied on plastiguage, but have always been a littl leery of it. I have A LOT of money invested in this, and dont want any unforseen explosions. This block is window free, and dont want any installed for a long time. Kasey

Re: Crank Measuring part 2 [Re: Moparnut426] #207247 01/29/09 10:34 AM 01/29/09 10:34 AM
Joined: Mar 2006 Posts: 9,910 Eighty Four, PA B G Racing master
B G Racing master Joined: Mar 2006 Posts: 9,910 Eighty Four, PA	If you don't have a good inside mic or bore gage,then buy your self a set of snap gages and measure your bore with your outside mic. [IMG]http://i430.photobucket.com/albums/qq21/ajcasini/max_zpsdppwd9km.jpg[/IMG]

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