Printable View
My taper measurements
Mains
#1 .0003 max
#2 .0001
#3 .0001
#4 .0002
#5 .0002
Rods
#1 .0001
#2 <.0002
#3 <.0002
#4 .0001
#5 <.0002
#6 .0000
#7 .0001
#8 .0001
A machinist will be double checking my measurements along with checking for straightness/mag. Hoping to drop this stuff off sometime next week. Now it's time to check out these Eagles and see how bad they are out of the box.
TIR? So .000015 on the main worst case? lulz thats good, prob better than what you are measuring with can accurately show.Quote:
Originally Posted by Catmaigne
What did you support the crank on?
Yeah, TIR. I don't have a donor block yet and mine is still in the car so all measurements were done with the crank standing straight up. It's definitely reading a ton better than the freshly ground 350 crank and the fillet radius is a work of art.Quote:
Originally Posted by shownomercy
I pulled an Eagle rod out the packaging and it's already .0002 out of round on my bore gauge. Haven't even stretched the bolts yet and I doubt they do it at the chinese factory. This might not be worth my time lol.
How did you manage to measure it standing up? Curious on that one
It was a bit of a balancing act with the mic resting on the area between my pointer finger/thumb and my elbow planted on the workbench or a box to keep things steady. I used my thumb and fingertips to keep the mic as horizontal as possible and do a very very small amount of adjusting while ratcheting the thimble to make sure it wasn't crooked. I was getting repeatable measurements each time and took a total of 6 readings (60* apart, 3 overlapping) each go round for both top and bottom of the journals. Definitely a pain in the ass but I didn't want to set the crank on its side because dual planes never look supported laying down. Couldn't find any real problem areas and worst was main #1 (although, still within spec) but I definitely want a good machinist to double check in a fixture or something.
Just wanted some preliminary readings before spending any $$$ on this thing. It's used so I had no idea what to expect when it showed up in a cardboard box. Definitely have a little more confidence in it now.
What, now you have me confused, you measured taper and runout with a mic..? Taper I can see being doable, but TIR needs a dial indicator no?
I think I misunderstood. Not entirely sure how one would go about using a regular dial to measure anything other than total crankshaft runout or thrust. Maybe an expensive arnold gauge on a crank grinder but I can't imagine that being practical to use for simple measurements.
I thought it was common practice to use an outside mic with .0001" units to measure the journals. I mic'd it in several spots radially right in the center while making sure to avoid the oil holes. I got the out of round measurements by simple subtraction of the max-min which is what I thought you were referring to by asking TIR (d'oh). I later compared those measurements to the ones I obtained while looking for taper to make sure there weren't any low spots near the edges I could have missed (top and bottom of each journal) and everything was still within my initial roundness spec.
I'll be dropping this thing off tomorrow so I'll report back with what my machinist thinks. Biggest concern as of right now is straightness because I know the crank has been sitting in a box for a while. It was padded with styrofoam but I've always been told to hang cranks from the snout or stand them up on end regardless.
TIR/concentricity is the relation to axis(es) to each other, so while you may have perfectly round journals (which it sounds like you do) the relationship of say #1 to #3 could be off. Usually you stick the piece of some blocks and then zero a dial indicator on one journal. Then move indicator across marble to the next journal to compare axis of the two circles.
Fun stuff no? :lol: Way to much dimensioning at work lately.
Sounds more like indexing and a lot of those measurements can vary with different v blocks and crank grinders that need calibration. I'll have to ask how much it would cost tomorrow. On the other hand, if it checks out to be straight and crack free I'll probably just get it polished and run the thing. I can tell Lunati's machine work was on the money being that it still mics up better than a lot of new cranks despite being used. I know these ran a pretty penny back in the day.
Still waiting on the crank & rods... it's been a week since I dropped them off at the machine shop. Any day now...
Don't think I ever posted pictures of this stuff. It's been collecting dust.
http://i1081.photobucket.com/albums/...ps430ea9a4.jpg
http://i1081.photobucket.com/albums/...psd7555119.jpg
http://i1081.photobucket.com/albums/...ps7e6c8b6d.jpg
Probably going to have send the Cloyes back or just buy a shorter chain for it. Not sure how much the 4-bolt conversion will affect the crank position. I guess it depends on how good the machine work is but I definitely want as little slack as possible.
I got the caps for $180 without the Howards logo. Billet steel and 10* splayed. Definitely will take the abuse.
Those are ARP main studs (w/windage tray) and ARP head bolts. Being that this is a street car build, I decided against head studs because of sealing issues and easier head removal in the car.
I also have a Melling Select 10554 std vol/high pressure oil pump. This is the pump with the more robust casting, steel gears, and hardened drive shaft. Just need the pickup for that because I will be reusing the stock oil pan. Not sure if I want to modify it or not but I'll definitely be adding some bungs with a Vortech (the D1SC is self contained).
Clearances I'm shooting for.
.0021 on the rods
.0025 on the mains with the rear around .0029"
Car probably isn't going to see past 6500 RPM with the same cam in a 383. The order swap means less crank deflection so I'm probably fine without running the mains super loose. I wouldn't want that on a street car anyway that will be using 5W30 synthetic.
I'm tempted to run a small 1-qt accusump for priming at startup. I may also consider a small oil cooler depending on temps but I certainly don't want to overload my std volume oil pump and lose pressure (especially if it has to feed a blower too).
edit: still curious about what clearances to run... I'll ask around. Definitely don't want it too loose with a SV pump.