502 MPI build up
11-26-2018 | 10:01 AM
#11
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From: St. Pete Beach, FL
The key differences are the heads, cam and exhaust. I believe the intake is the same.
525s have edelbrock heads. There are better aftermarket options. Cam is similar to crane 741 which is good for what you’re doing. You should skip the 525 exhaust and use the thunder n lightning.
525s have edelbrock heads. There are better aftermarket options. Cam is similar to crane 741 which is good for what you’re doing. You should skip the 525 exhaust and use the thunder n lightning.
11-26-2018 | 11:22 AM
#12
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From: SF Bay Area
If you stray very far from stock add in another $1500+ or so for redoing the oil cooler and fuel systems. I’d freshen up the short block to marine specs, have some good heads built, massage the intake system, and enjoy boating for another decade or two.
11-26-2018 | 01:12 PM
#14
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From: Midwest & T-Rock
11-27-2018 | 11:01 AM
#15
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From: Baltic Sea
without heads i would not get the 540hp, right?
As i asked... ( double 58mm trottle body, rip down the intake diverters, put in a 525 or similar cam, pistons wich add litte bit more compression rate (we have 95 fuel), a little porting, ecu reprograming ) what do you think i could get out of it?
As i asked... ( double 58mm trottle body, rip down the intake diverters, put in a 525 or similar cam, pistons wich add litte bit more compression rate (we have 95 fuel), a little porting, ecu reprograming ) what do you think i could get out of it?
11-27-2018 | 11:04 AM
#16
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From: frankenmuth michigan
I saw 560 hp in dyno trim from a 502 w modded intake, 68 mm tb, 731 cam and lots of tuning on 89 octane. Iron heads w mild porting. Tpis bores throttle body from twin 60 mm stock to 68 mm for 270$ btw
11-27-2018 | 12:07 PM
#18
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From: Portland, OR
How much did just the throttle body alter the tuning in your case I don't recall if you mentioned it specifically?
Last edited by Diamond Dave; 11-27-2018 at 12:27 PM.
11-27-2018 | 02:25 PM
#20
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From: St. Pete Beach, FL
make sure you understand the difference between dyno trim and in your boat. Highly dependent on your exhaust manifolds and how many pumps you hang off it.
