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502 Mag engine noise with video.

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Old 04-24-2017, 08:18 AM
  #41
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New heads and gaskets and run her for the season if the piston's can be "cleaned up"
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Old 04-24-2017, 12:44 PM
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Bores look ok, at least what we can see. Take a die grinder or dremel or something and remove the high spots on the pistons. Scare up a set of heads don't even hafta be rectangle port. Don't use L29 heads with those pistons. Engine may be good for years.
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Old 04-24-2017, 12:54 PM
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Still wonder why so little oil was on the rockers
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Old 04-24-2017, 02:55 PM
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Anyone know where to get a set of gm rectangle port heads from. All I keep seeing is they are no longer available. and if I switch to an aftermarket head i have to have the ECM programmed.
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Old 04-24-2017, 03:16 PM
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What's the casting number on those heads?
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Old 04-24-2017, 04:25 PM
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I believe the Engine Quests are a direct bolt-on. You'd only need a set of adjustable rocker arms (or reuse your rocker studs and such).
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Old 04-24-2017, 04:29 PM
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Quote:
Originally Posted by picklenjim View Post
What's the casting number on those heads?
12562934 or 14097088. The 2 common gen 5-6 rectangular heads.
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Old 04-24-2017, 04:37 PM
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a guy up around boston has a couple sets of 088 heads. BWD is his OSO name. PM him.
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Old 04-24-2017, 04:42 PM
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Quote:
Originally Posted by TomZ View Post
I believe the Engine Quests are a direct bolt-on. You'd only need a set of adjustable rocker arms (or reuse your rocker studs and such).
These. Have not heard anyone here using them yet...I have course have with their 320/360 performance heads.

Quote:
Chevrolet 502 Cylinder Head - Cast Iron - Engine Quest CH502A:

NEW HIGH PERFORMANCE 502 GM HEAD fits GM, MerCruiser, OMC and Volvo Penta.

High Output Performance/ Marine Cast Iron Cylinder Head, Gen V and Gen VI Rectangular Port. This head is produced in our New Zealand foundry using the highest grade cast iron in the industry. Heads are equipped with the Dura-Bond ultra durable exhaust seats for extended life in rough performance and marine applications. The cylinder head is manufactured in the “stock replacement” configuration with integral valve guides and standard valve diameters built into this 26 degree head.

299cc intake runner
2.19" head diameter Intake valve
1.88" head diameter Exhaust valve,
118cc combustion chambers
1.52" valve spring pocket width
Integral guides. 3/8" ID
7/16" accessory mounting holes
Power improved intake runner.
replaces casting number 14097088 (use in pairs)
replaces MerCruiser part numbers 938-5924 & 938-814512
Use ARP 135-7102 Screw In Studs to convert from Bolt Down Rocker Arms to Adjustable
What Makes an EQ Cylinder Head better than the rest?

•Highest grade of material used in manufacturing
•Thicker decks for greater strength
•Superior port finish for increased flow
•Improved flow design to resist cracking
•Redesigned water flow for greater thermal conductivity
•Hardened exhaust seats
•CNC machined guides and seats
•3 angle valve finish
•Parts and labor warranty *
•25 point quality check on every head
•Assembly of bare cylinder head casting should be done by qualified machine shop
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Old 04-24-2017, 04:50 PM
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Quote:
Originally Posted by RGPIII View Post
Anyone know where to get a set of gm rectangle port heads from. All I keep seeing is they are no longer available. and if I switch to an aftermarket head i have to have the ECM programmed.
You will not need the ECM programmed with a similar performing head installed.
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