502 MPI build up
11-25-2018, 11:52 AM
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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
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
11-25-2018, 06:15 PM
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You would need to budget around 35k to build a 540 or buy a 525 efi. or rebuild what you have and go boat
11-25-2018, 10:35 PM
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11-25-2018, 10:38 PM
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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
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
11-26-2018, 05:15 AM
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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?
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?
