Main Studs??

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80fbody said:
Challenger - This is not something that can be checked at home, correct? I have a dial bore gauge but there's no way to tell the alignment is correct. Reason I ask is my latest block is studded with a fresh line hone. Would certainly like to be able to tell if it was done properly.
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I think you could do it at home ? why not ? Do you have a Dial Bore Gauge ? ....even a cheapo 2-6" would suffice in 1/2 Thou increments ?
They only cost like $90 Bucks... great for checking Bearing Clearances etc at home ?
Set the cheapo gauge to "Zero" off your Crank Sizing.... then measure the Bore WITH the Bearing in there Torqued up.... Presto... READ your Clearance.
If you JUST want to check the Main "Bores", set a Micrometer to 2.9425" on an RB Engine(440)and then transfer as "zero" on the Bore Gauge, go in and measure "vertical", and 45* Off either way.... check straight & round.
As far as Alignment DOWN the Block.... all a Guy can do is look visually for any evidence, or lack thereof of Cross hatch from the Hone on particular Caps,
or,
Get a machinists straight edge than will span 3 Caps, and start with a feeler gauge.

Nonetheless,
Plasti-gauge is for goofs !
Yes, the Bore Gauge WILL leave a small "pecker-track" across your bearing... just wipe it clean... with a soft lint free cotton rag on your finger.
Kinda gratifying to get your clearances right !!... and "see" your old Bearing Clearance marks 2-3 seasons later, still there on the Bearings when re-freshening an 800 hp deal ??
 
my only concern is that i have seen many times a guy measures clearances at home and its off

Be it :

cheap tools
inexperienced hand
temperature change from home to machine shop

etc

mainly a machinist who has 30+ years knows how hard a gauge should drag to get REPEATABLE results all day, every day to obtain clearances in the thousands of an inch.
 
DJVCUDA said:
my only concern is that i have seen many times a guy measures clearances at home and its off

Be it :

cheap tools
inexperienced hand
temperature change from home to machine shop

etc

mainly a machinist who has 30+ years knows how hard a gauge should drag to get REPEATABLE results all day, every day to obtain clearances in the thousands of an inch.
Click to expand...

All too true, and not to be taken lightly. There is a lot of "feel" required when you are in that range of measurement. My only point was to check it, or have it checked, and only machine something if needed. Bearing bores are in the ten thousands of an inch, 1/10,000 and .0005 total, typically. I've seen and heard of shops ruining, in my opinion, blocks by align honing and changing the centerlines between the cam and crank so custom timing sets are required.
 
Confusion,

If you're going to spend $90 on a 'Cheapie' Dial-Bore Gage, you would be
better off putting that money towards an Align Hone Job.

And, not to get off on the wrong track, but we've had several Engine Blocks
come into our shop after an Align Hone Job, and the Mains were F***ed up
{Too Tight}.
 
Challenger 340 is correct. Ive owned and operated a machine shop for some time, and believe me, they all distort! One thing I will add to this is that Ive noticed that the BB mopar isn't as prone to distortion due to the quality structure built around the mains. The small block is horrible, whereas the crank is "hanging" outside the lower panrail. They almost always need align honing. Just my 2 cents
 
I suspect some of you guys would freak if you saw how top fuel/fc mains are line honed on the road. Boring bar and a big corded hand drill, ran free hand with block on a regular (floppy) engine stand. No guide bars or anything like that. We would even pull the drill in the direction of the tight spot. Put crank in, spin it. If it's free and bearing clearances math out (bore-crank size) it's good. Definitely not a precision perfectly straight main line!
Granted, they only live for a little (8 runs max) while but it sure looks barbaric by normal engine standards.
I'll see if I can find any pictures on my old phone.

I'd agree that any "normal" engine that needs studs really should have main line checked. Doing one and not the other seems like asking for easily avoided trouble. And if ya can't afford the line hone/bore, you won't like the parts bill when you smoke the crank or worse.
 
moturbopar said:
I remember when I was younger, and had a lot more fun with cars, we used to throw stupid stuff together. We built a 307 chevy (I know LOL!) that was thrown together, stock cast pistons, double hump heads, 2.02 1.60 valves, home ported, We threw arp rod bolts in the stock rods, no machining, arp main bolts, again no machine work, and a comp 270h. I have no Idea how that engine held together, or even ran. was in a 65 cj5. with 4.27 gears and the stock 3spd trans. Thing was pretty dang quick, won a lot of street races (don't do it anymore!). That thing regularly hit 6500 rpm with a couple missed shifts hit 7000+! Anyways I grew up and learned better, But unfortunately, it costs me a lot more $$$ to build engine now. But for some reason I just have this urge to build a JY engine, on the cheap, say screw the rules lets see what happens!
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something all of you missed is: most mainstuds I have used are of a larger diameter than the necked down stock bolts from the factory. it is possible to install them and move the main cap some small amount. some will, and some wont. always better to check and see ! I like to have mine line honed myself.
 
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