diffuser plates in giil/merc exhust? AND CRANK QUESTION
#1
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while taking the motor out because of a rod nock (PRO CHARGED HP 500) i found the exhust was missing the diffuser plates that i saw in the service manual.the last owner must have removed them.are these diffuser plates needed what are they for? Also my engine builder just tore it down most of the rod bearings are shot whoever built it didnt mic them or somthing.so were going to put in a nice 4340 rotating assembly and im going for the edlbrock aluminun rectangle port hard coated marine heads.we were talking about cranks and since its a gen 5 with a 1 piece rear seal he wasnt sure who made a good 4340 crank for it.it needs a 4 inch stroke crank thats external balanced which id rather stay with so i dont have to buy a balencer and fly wheel.he mentioned they make a adapter for the 2 piece seal cranks but said there more prone to leak and is going to see if he can find a good i piece seal gen 5 crank.im looking for somthing like a callies DS crank.with all the engine builders on here somone must know who makes a good 4340 1 peice seal crank.even if its int bal its ok ill just have to buy a internal balance fly wheel and balancer.thank sean
#2
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The diffuser plates stop condensation ,that will form on the inside of the riser pipes after shutdown, from running down into the manifold. They do nothing for reversion.
I can't help with the crank issues.
I can't help with the crank issues.
#3
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krypto, Sorry to hear about your engine problems. That sucks.
It would make me nervous as hell if my engine guy told me he did'nt know who made a good crank for my engine. With heads, crank, intake, etc. you're getting into a major rebuild.
They say every cloud has a silver lining. And this sounds like an opportunity to make some improvements. If it were me I'd be patient and wait to see what the engine gurus here on the site have to offer. No doubt you'd get great advice. Just my .02.
It would make me nervous as hell if my engine guy told me he did'nt know who made a good crank for my engine. With heads, crank, intake, etc. you're getting into a major rebuild.
They say every cloud has a silver lining. And this sounds like an opportunity to make some improvements. If it were me I'd be patient and wait to see what the engine gurus here on the site have to offer. No doubt you'd get great advice. Just my .02.
#4
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my engine guy does know his stuff well.he didnt build this procharged hp500 i bought the boat with it from from a broker in long island tri state ultra boats. in a screwy deal where the motor was out at the boat owners engine guy getting rebuilt and i put a deposit on it and waited a month for them to finish and install it obvously i got screwed and somone slapped it together fast and cheap as it was alkready sold.the motor only had about 10psi oil pressure idling from when i picked it up and no build sheet just a guys name who did it.everything rigged backward boost refrence line to intake manifold carb dumping fuel the down motor which probably helped wash out the bearings.half the bolts were hand tight i had to go through everthing.fist i was told zull racing was doing the motor then a place connected with zull and to be dynoed at zull then have a hard time even getting the phone # of the guy that built it.i guess it goes to show you how not to buy a boat.i have pat musi performance doing the motor who mostly builds huge 632ci+ nitrous motors for drag racing and does about 20% marine he has done 3 motors for me 2 for drag racing and a 555 merlin marine motor for my old boat done last year it made 704hp NO BLOWER just 9.1 with a single holly 1050 and has run flawlessly (a friend owns it now) wish i had it still to throw in the kryptonite.the thing is pat is used to doing gen 4 blocks like merlins that use the 2 piece seal cranks so just off the top of his head he wasnt sure who made a good gen 5 crank.yeah it bites just bought the boat over the winter and around 5 hours a rod nock so im stranded on land for a little while.at least its apart and in the hot tank and pat gets them done fast it will be on the dyno in a few weeks so at least ill have some season left.and like you said ill be able to get it how i want it now.it was going to come out and get done over the winter anyway.one thing that bugged me was i really didnt like the stock oil system capacity.a hp500 with a pro charger and it only held 8 qts in the whole system.so i just ordered a 10qt gill offshore pan from teauge to go on it.also got a couple different size pullys from procharger to try it on when we dyno it since with the larger edlebrock heads and a larger bore (4530)it might loose some boost.it now has a 4.25 pully and they just sent me a 4 and a 3.85 to try.so it should rip i went 91.6gps with it before so with the heads and a few other goodies and done correctly it should just about see triple digits.
#5
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Krypto:
I am pretty sure Eagle, Callies, and Scat make the 4340 crank you are looking for.
Sorry to hear about guys ripping you off on a bad motor. Good Luck on the rebuild.
Ray @ Raylar
I am pretty sure Eagle, Callies, and Scat make the 4340 crank you are looking for.
Sorry to hear about guys ripping you off on a bad motor. Good Luck on the rebuild.
Ray @ Raylar