Shotgunn

That could be right too. It looked like stock lines were 1/2", If I do it again with a big cooler I will likely go with -10 or-12.

articfriends

you must have had the earlier mk4 or gen v carbed oil cooler to start with. Its 2.5 times bigger then the gen V ,gen vi mpi oil cooler which is about 2" od and 6" long. The newer, tiny stuff I'm talking about used a bunch of flared lines with tiny passages about 3/8 id I rebuilt a early carbed 502 a few years ago, it had what apoeared to be 1/2" lines and cooler about 15 or 18" long. Block bypass is important, theres been countless lost motors where a 5 or 6lb bypass was installed vs the 25/30 lb bypass and high volume oil pump will force it open allowing un filtered, uncooled oil to circulate.

Shotgunn

Holy smokes! great information right there. I used the stock 502MPI bypass, dont know the relief pressure on it. My cooler is the bigger one. Oil temp monitor will be mandatory on next build.

articfriends

.Ive never purchased a oem merc bypass but I have bought quite a few of the GM heavy duty bypass valves. Its my understanding the marine engines use the same hd one , not the standard low pressure one passenger cars/trucks use. Some guys just plug them solid, I always leave the center bypass/check valve out, its just a antidrain back valve from what I understand and its another thing that can pose a restriction in oil flow, Smitty

Rookie

Plug it if you get a chance.

Shotgunn

Great info! I am on the verge of entering the twin regime, so you know now it will take twice as long to save for new builds lol.

BlueAndWhite

I have the engine out of the boat, took the pan off and its a 2 bolt main. at least now i know wat im working with.
il go check out that Skipwhite website. thx for all the input guys!

Brad Christy

BlueAndWhite,

I am told that converting a 2-bolt to a 4-bolt is as easy as drilling and tapping the holes. The material is there in the block. I know I've seen kits for spayed bolt caps that allow for converting to these style caps that include drill and tap bushings that allow an industrious individual do the work with a hand drill and tap wrench. Might be worth and looking into.

Thanks. Brad.
Model Machine and Precision LLC
(937)545-8991

articfriends

With a goal of 500 hp , at most I would do is stud it and have it align honed

BlueAndWhite

I wanted to thank everyone for giving me input and advice.
After I missed out on a few engines I finally found one that wasn't sold or had a deposit on it. Brought it home last night.
Not sure if I have enough post count to post pics but here are the details:
Drop in ready from carb to pan with all accessories and TMI thunder manifolds for 9k cad
its purple...
502 block, bored to 509
holley 850 double pumper
haven't open the valve covers yet but I've been told it had merlin heads and some roller cam setup.
seems to be a supped up hp500 motor
Dyno sheet shows 573 peak power and 612lbs of torq.
Its not a fresh rebuild but it had 150+ compression all over and was told roughly 250 hours