Re-drilling Mercury Headers for 525, 600 to fit standard bolt patern

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10-05-2012, 06:29 AM

F-2 Speedy

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Re-drilling Mercury Headers for 525, 600 to fit standard bolt patern

Anybody done it, is there a template out there, Going to be running AFR's on my rebuild, I found some headers off a 600, wondering how big of a pain in the A$$ it would be to redrill them to fit, I was told the two outside bolts line up but the others dont, is that correct. Or should I keep looking.

10-05-2012, 06:32 AM

smokin' gun

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yes that is correct .i think its 3/8 ths diff .i use a gasket as a template simple job .go easy drilling though its stainless

10-05-2012, 09:05 AM

C_Spray

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...I'd suggest welding up the old holes first, then drilling.

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10-05-2012, 03:35 PM

FIXX

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fixx

Quote:

Originally Posted by 33outlawsst

check with afr first to see if they can drill the head whyle its in the cnc..

10-05-2012, 04:40 PM

keegan

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just bolt down the two outer holes and call it good!

10-05-2012, 05:50 PM

F-2 Speedy

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Quote:

Originally Posted by keegan

just bolt down the two outer holes and call it good!

funny guy, how ya been

10-05-2012, 06:45 PM

FIXX

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fixx

Quote:

Originally Posted by riverrat

what if he ever wants to sell the heads , or has to change one due to catastrophic failure ? could be a cluster f
Jeff

what if the header fails and he has to do it all over again...lots of what if's..me personally i wouldn't even consider a cmi header..stelling is out and the only other option woulf be lightening or hardin ..those two are made alot better then cmi...i have a customer that i installed a set of lightenings 12 yrs ago and their still mint and the outer pipe in steel..got friends with cmi's and they all heve been sent back and they still had problems with them cracking or leaking at the welds..

just my o2..