repair or replace 350 crank?

[Grumpy]

I bought a 350 short block off craigslist for $100. I'm slowly taking it apart and assessing things.

One of the areas of concern is the crank. So the shortblock had been rebuilt at some point before. It's already 30 over and at least the rod journals are ground 10 under. The number #1 main bearing looks pretty trashed, but the crank doesn't appear worse for the wear. The most troubling issue is the crank snout. It appears to have been drilled out from 7/16-20 to 9/16-12. The threads do not look great and the angle is not straight. There's also a noticeable lip where the harmonic balancer ended.

So the idea for this build is I want to build some torquey grunt to push our 85 caprice around, and to have fun assembling my first engine. The engine won't see more than 2500 for sustained periods, highway cruise will be about 1500. A new cast crank is only $200 plus the cost of balancing. Is there any hope of fixing the crank I have or should I just replace it?

Crank threads

#1 Main bearing

personally this is a total non-question, the risk vs cost savings say, even scream...throw that crankshaft in the local trash can.
why take the chance on a crank that has both non-standard journals,
that were obviously cut undersized too allow over size bearings as a previous repair,
and a crank of un-known history, that obviously has been ,
subjected to who knows how much stress, probably for decades.
cranks are fairly cheap, any large local machine shop will have both cast and forged 350 and 383 cranks either on the shelf or available on short order,
along with much stronger than stock connecting rods and its certainly going to be a whole lot cheaper to purchase and install a new crank now ,
vs repair the damage if that suspect crank breaks or throws a well stressed used rod even if they are reconditioned, rod .
and because your in the engine re-build process,
you have the choice and the motivation too upgrade to a 3.75: stroke version to build a 383.
that extra 1/4"in stroke, the added displacement that results, is worth an easy 35-40 additional ft lbs of torque and 35-45 hp.
read the links it will save you a great deal of problems,
a few days spent reading related and useful,
linked info,
will surely save you hundreds of dollars and weeks,
of wasted effort and problems from assembling the wrong components,
and avoid making bad and expensive wrong choices.
(yes it will take you a good deal of time as theres dozens of sub-links,
but in the long run its going to be far faster and easier)

http://garage.grumpysperformance.co...ould-you-build-a-350-or-a-383-sbc-combo.8310/

http://www.scatcrankshafts.com/rotating-assembies/rotating-assembly-product-search/

http://garage.grumpysperformance.co...tion-of-crank-durring-short-blk-assembly.852/

http://garage.grumpysperformance.com/index.php?threads/383-information-overload.11137/

http://garage.grumpysperformance.co...ng-and-basic-piston-ring-info-youll-need.509/

http://garage.grumpysperformance.co...g-and-installing-connecting-rods-pistons.247/

http://garage.grumpysperformance.co...ing-parts-and-a-logical-plan.7722/#post-26314

http://garage.grumpysperformance.co...-calculators-and-basic-math.10705/#post-70311

http://garage.grumpysperformance.com/index.php?threads/maximizing-piston-to-bore-ring-seal.3897/

http://garage.grumpysperformance.com/index.php?threads/bits-of-383-info.38/page-2#post-61958

http://garage.grumpysperformance.co...k-for-in-a-good-engine-combo.9930/#post-46399

http://garage.grumpysperformance.com/index.php?threads/a-basic-350-build.8929/#post-31759

http://garage.grumpysperformance.com/index.php?threads/rotating-assembly-bearings.9527/

http://garage.grumpysperformance.com/index.php?threads/what-con-rods-would-you-buy.942/

http://garage.grumpysperformance.co...gine-to-match-the-cam-specs.11764/#post-55571

http://garage.grumpysperformance.com/index.php?threads/oil-system-mods-that-help.2187/

http://garage.grumpysperformance.co...trong-will-a-scat-rotating-assembly-be.11495/

 

[Grumpy]

a couple 383 sbc parts

http://www.ebay.com/itm/SCAT-SBC-CH...00-/351305992490?_trksid=p2385738.m2548.l4275
rods $260

http://www.jegs.com/i/Scat/942/9103750/10002/-1
crank $210

http://www.jegs.com/i/United-Engine-Machine/648/9906HC.STD/10002/-1

pistons $217
rebuilt or new chevy 383 crank
http://www.superchevy.com/how-to/project-cars/sucp-0706-small-block-chevy-stroker-kit/

keep in mind youll need to replace the rings, bearings, gaskets,
cam and lifters, timing chain and damper on any rebuild and you'll more than likely need new pistons in any case,
especially if the bores are not in great shape even on a 350 or a 383,
, so the difference between a full refresh on a 350 vs building a 383,
with better and stronger aftermarket SCAT forged connecting rods and a new crank,
will most likely be about $700 -$800
, once the machine work like balancing clearancing, etc, is complete
it helps a great deal if you take the time and effort to find a trust worthy and reasonably priced local machine shop ,
and trust me when I say this is critical, and yes, the machinist will seem to point out endless things that should be done to increase durability,
or just allow proper component function,and a good machinist will try to guide you in component selection,
to help avoid mis-matched parts and low quality parts being used,
yes quality parts and machine work,
ALWAYS COST more than you may expect them too!
heres two well thought through engine builds, and several related links
they will take a while to read through the links and sub-links
[color:red]but[/color]
if you take the time and effort to read all the LINKS and SUB LINKS YOULL LEARN A GOOD DEAL
I think the hamburger oil pan is a better value At $242 than most of the common mid priced oil pans
notice the better oil control features
https://www.summitracing.com/parts/ham-1088/overview/

http://www.milodon.com/oil-pans/street-oil-pans-sbchevy.asp

http://www.jegs.com/p/Moroso/Moroso-Street-Strip-Oil-Pans/763991/10002/-1

https://www.summitracing.com/search/brand/hamburgers-performance/part-type/oil-pans

https://www.cantonracingproducts.com/cgi-bin/commerce.cgi?search=action&category=1301

http://www.stefsperformance.net/ste...oil-pans/aluminum-oil-pans-pumps#!prettyPhoto
BUILD THREADS

http://garage.grumpysperformance.com/index.php?threads/tbucket-engine-project-dart-shp.3814/

http://garage.grumpysperformance.com/index.php?threads/renegade-intake-for-cross-fires.2796/


USEFUL RELATED LINKED INFO

http://garage.grumpysperformance.com/index.php?threads/what-to-look-for-in-a-good-engine-combo.9930/

http://garage.grumpysperformance.co...le-that-don-t-use-resources.12125/#post-58374

http://garage.grumpysperformance.com/index.php?threads/383-information-overload.11137/

http://garage.grumpysperformance.com/index.php?threads/bjautos-383-build-pictures.9483/

http://garage.grumpysperformance.com/index.php?threads/tips-on-building-a-383-sbc-stroker.428/

http://garage.grumpysperformance.com/index.php?threads/stroker-tips-by-len-emanuelson.1249/

http://garage.grumpysperformance.co...ty-thats-key-in-building-a-good-engine.11682/



http://garage.grumpysperformance.co...-the-rabbit-hole-with-alice.10933/#post-48014

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-68861

http://garage.grumpysperformance.co...d-what-goes-in-the-dumpster.13135/#post-68642

http://garage.grumpysperformance.com/index.php?threads/bare-minimum-tools.11026/#post-51823

http://garage.grumpysperformance.com/index.php?threads/tweaking-a-350-383.13087/#post-68201

http://garage.grumpysperformance.com/index.php?threads/what-con-rods-would-you-buy.942/#post-67580

http://garage.grumpysperformance.com/index.php?threads/another-383-build.12786/#post-66036

http://garage.grumpysperformance.co...ting-started-in-the-car-hobby.339/#post-60236

http://garage.grumpysperformance.co...on-building-a-383-sbc-stroker.428/#post-61899

http://garage.grumpysperformance.com/index.php?threads/finding-a-machine-shop.321/#post-59253

http://garage.grumpysperformance.com/index.php?threads/a-383-build.10991/#post-48513

http://garage.grumpysperformance.co...piston-to-bore-clearance-on-your-block.14251/