I'm building up a new motor for the car. I got a crankshaft that needs some repair. I'm just wondering how much it'll cost. The crank is in relatively good condition except for one rod bearing journal. It may need to be undercut to fix it. Also, I would consider lightening it (if it's possible). I've never had any work done to any crank. For all of the rebuilds I've done, I suppose I've been fortunate enough that the crank was either not involved or just good to go. But now I have this crank and it needs fixing. It looks like it can be fixed up. So I guess I have a few questions.

1) How much should it cost to have the rod/main journals polished?
2) How much should it cost to have the mains polished and the rods undersized and polished?
3) If I undersize the main journals, do I HAVE to undersize the rod journals?
4) Should I bother with having it balanced? If so, how much should it cost?
5) Is it possible to lighten these crankshafts? If so, how much should it cost - and approximately how much lighter can we make it? If anyone could shed some light on specifications for lightening process that would be great too. Like - how much should be machined from the counterbalances? Also, how it should be done - machine layers from the counterbalances or just drill the tops?.
6) Should I be looking for a shop that has any particular processes that are specific to crankshaft repair? I really don't know if this question is phrased quite right - Really I'm interested in knowing wheather I should I give this job to a "general" machine shop or should I give the job to a more "specific" shop - like an engine builder shop or something like that. Please tell me if you don't understand this question - I can't think of how to be more specific with it at this moment.

I know that if I do get the crank lightened that I definately want to have it balanced as well - I would make sure that the shop could do all of that in one shot. I'd rather know what you guys do about machining costs as well as the lightening possibilities for our crankshaft before commiting the work to a shop.

I guess one last thing is...I suppose I could get an answer like "Give this job to shop X - They'll get you revving like a bike!". It only cost $12 to have it shipped here, so that's not too bad. I don't think shipping costs would prevent me from considering a shop thats out of state(I live in West Chester, PA). Just, if you do have a shop that you think could hook me up - please explain why(cost, precision, expertise).

Thanks.


95 Eclipse RS : 5 speed
Jeep TB writeup - http://www.dimensia.com:81/jimbo/JeepTBfor2gnt.html

An good machine shop (key word = "good") should have the ability to clean up the crank for you. If you are going to start balancing things, I say pull the pistons and rods, get the entire rotating assembly balanced, that's usually around $100.

I'd get some recommendation from people in the area. Any car clubs talk to the guys. I asked at ASOG, Neons.org an a local Neon board and found a good machine shop for my head work, a guy who was familiar with the 420A too.



15.9 @ 86.7mph

Injen CAI, 55mm TB, P&P Intake, Crower Cams, Hooker Header, ERT/Catco Cat, GS-T Muffler, AFX UDP, Crane Ign Amp, S-AFC

Ah - yeah that's right. You can get the whole assembly balanced. $100 doesn't sound too bad for that. This motor doesn't actually exist yet - so taking everything to the shop shouldn't be a problem. So far I have a block/bedplate from Kiku, crank from 2gdsm_nc, a headgasket from Widebodied, and .060 over 10:5:1 CP pistons/Wiseco rings/Eagle rods from Blackdog Motorsports. The pistons/rods should be here in a week or so...along with a set of Blackdog rockers that I splurged on.


95 Eclipse RS : 5 speed
Jeep TB writeup - http://www.dimensia.com:81/jimbo/JeepTBfor2gnt.html

Very nice.

You'll like the black dog rockers, I have them, they are a very nice piece.



15.9 @ 86.7mph

Injen CAI, 55mm TB, P&P Intake, Crower Cams, Hooker Header, ERT/Catco Cat, GS-T Muffler, AFX UDP, Crane Ign Amp, S-AFC

Thanks Michael.

So um...can someone tell me what they've spent on getting their crankshaft turned or polished? I'd just like to know what a fair price is.


95 Eclipse RS : 5 speed
Jeep TB writeup - http://www.dimensia.com:81/jimbo/JeepTBfor2gnt.html

On my street/strip 351W I'm just about to get out, he charged me $90 to turn and finish the crank. (BTW it won't be any cheaper w/ 4 cyl stuff) Rotating assembly is gonna be $120 to balance. That includes my rods matched, lightened crank, and making it all work properly with my bearings. Yes you can have just the rod jounals turned and the mains left alone. You will have to buy the correct bearings. I'd keep all machine work in the state. If they need something or you want to look at what they have done, it's hard to fly or drive to another part of the earth just to see your stuff.

Around here, I asked most of teh machine shop around me (30 miles range) and they all charge me $15x for resurface the crank shaft.. that's crazy.. I can get a new one from Autozone for $158.
Gil

it costs me 140$ for them to tank machine repalce freeze plugs and grind /polish the crank and or weld journals...

costs 150$ for them to balance the rotating assembly....

Autozone sells new 420A crankshafts?!?

Not BRAND NEW>.but they re-finish them to stock new crank spec.. which is only $158.
Gil