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Bang Bang 11-25-2018 11:52 AM

502 MPI build up
 
Last ride this season just right back at the harbor i lost a valve seat. Now i am looking for opinions what to do. The motor sits in a 26 Hustler and did 70mls w/ stainless marine exhaust. I am looking for 80. Had a look in older threads, it seems like i can get 500hp with riping down the intake dividers, cam, ecu, exhaust.... I don't think this will do 80 mls in the hustler. Means i'm looking for 525-550hp i think.
The big question is should i do all this with a 18 years old motor or better go with a 525 efi?
What could i add to the 502 wich makes sense? Make it a 540? 7.5% more displacement is not much, even if you look for hp in the 5000 rpm area.
Heads? Are Dart, Brodix, AFR... a big improvement? Mine is not in the best shape anyway but can be repaired as well.
I could open up the throttle body a little bit more if this is a part which makes sense....
tia
Andy

freekazoid 11-25-2018 12:12 PM

(585) 654-8583 bob madara will answer all your questions.

Baja Rooster 11-25-2018 12:36 PM

I would call Eddy Young as he’s super helpful and actually builds engines.

hogie roll 11-25-2018 06:01 PM

Calculator says you need 540hp. Replicating a 525 and improving some things is a good idea.

Smitty (articfriends) modifies those intakes too.

F-2 Speedy 11-25-2018 06:15 PM

You would need to budget around 35k to build a 540 or buy a 525 efi. or rebuild what you have and go boat

hogie roll 11-25-2018 06:20 PM


Originally Posted by F-2 Speedy (Post 4660879)
You would need to budget around 35k to build a 540 or buy a 525 efi. or rebuild what you have and go boat

I suspect you could do it much cheaper.

Crude Intentions 11-25-2018 09:12 PM


Originally Posted by Baja Rooster (Post 4660830)
I would call Eddy Young as he’s super helpful and actually builds engines.

+1 for Eddie.

Smarty 11-25-2018 10:35 PM


Smarty 11-25-2018 10:38 PM

My father had 502/415 mpi

He bought Dart short blocks, kept his heads and EFI, innovation dynoed both motors 520 hp and 519 hp

call Ateco,

do what my father did or consider the choice in my prior post



Bang Bang 11-26-2018 05:15 AM

35k is way too much. I mean it doesn´t make sense to try to duplicate a 525 wich is appr. $15k when i have to spend a lot in my old motor. I could sell my 502 for 2k, add 13k and get a 525. Or i rebuild my 502 and try to get close to the 540hp.
540hp seems to be right for 80mls. I totaly agree.
If i put on a double 58mm trottle body, rip down the intake diverters, put in a 525 or similar cam, pistons wich add litte bit more compression rate (we have 95 fuel), a little porting, ecu reprograming, what could i expect?
What would be the next steps? Heads? 540?


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