502 Rebuild questions
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502 Rebuild questions
Hey guys Newb here. Ive had multiple questions that I've googled in the past and always ended up here. Since it seems all my past questions were answered here I figured this would be the "go to". I picked up an extremely clean 1993 27' Baja Shooter with the 502 EFI and 321 hours a few days ago. It's is truly spotless and has been babied since day 1. It has 2 cylinders down and I knew this in the purchase. The motor has had a compression and bleed down test. It needs pistons, rings, and a new bore at least. Now to my questions. I plan to pull the motor and take it to the machine shop myself. I'll have someone reinstall the motor and drive to ensure proper alignment. What I need to know is what can the stock rotating assembly handle? I would like to do some port work and a cam when it goes back together. It came with headers already. What cam should I go with? Also, what is a good budget piston and what size? I believe my stock bore is a 4.47x4" correct? I'll post pics from the desktop for y'all. I'm on the iPhone now. Thanks in advance!!
Last edited by Paid4; 10-18-2012 at 06:52 AM.
#2
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if its a 502 mag, it should have forged internals, good stuff but have the machine shop double check, if it has the stock cast iron heads dont wast ur money on doing port work, unless its free. Bore it to a 509 they make good power and put the porting money towards some alum heads. Im sure some other fella's will chime in for a cam, JMO
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if its a 502 mag, it should have forged internals, good stuff but have the machine shop double check, if it has the stock cast iron heads dont wast ur money on doing port work, unless its free. Bore it to a 509 they make good power and put the porting money towards some alum heads. Im sure some other fella's will chime in for a cam, JMO
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a mag has rectangle port head's already, there preddy good, the bottom end can handle 700hp easly, witch your not going to get with just a cam. the best bang for your buck would be upping your comp with domed piston's to 10.5 to 1 and run GOOD 93 oct pump gas, but honestly your's should be fuel injected so in all honesty i would stay stock. Your computer will have to be reprogramed with any mod's and your opening a whole can of worm's to get your computer programed right.
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a mag has rectangle port head's already, there preddy good, the bottom end can handle 700hp easly, witch your not going to get with just a cam. the best bang for your buck would be upping your comp with domed piston's to 10.5 to 1 and run GOOD 93 oct pump gas, but honestly your's should be fuel injected so in all honesty i would stay stock. Your computer will have to be reprogramed with any mod's and your opening a whole can of worm's to get your computer programed right.
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yes
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Well Paid4 sold me the boat about 2 months ago and told me everything was fine with the it. Took it on the water last weekend and realized I have serious problem on my hands....****ing *******... good thing I found this...saved me from doing a compressions test and a bleed down this week.
Last edited by Richardsm850; 03-24-2013 at 12:23 AM.
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That's jacked up...I see he has only 3 posts and this thread was from OCT last year. I do not know if you have any legal grounds to go after him based upon his posts above. Hopefully some of the legal smart guys on here will chime in.
Sounds like it needs a top and bottom rebuild. I just did mine (top and bottom) and bored them to 509. It ran me about 5k for everything per engine.
Sounds like it needs a top and bottom rebuild. I just did mine (top and bottom) and bored them to 509. It ran me about 5k for everything per engine.
#10