Merc 7.4 330 to 502 Ignition change
06-07-2006, 02:05 PM
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Merc 7.4 330 to 502 Ignition change
Ok guys,
What is nessessary for me to change out as I swap out my old Merc with the new perfomance 502? I have heard that the factory ignition limiter is set to 4500RPM's? Please remember I am on a budget..
As always... thanks fellas.
Jared
What is nessessary for me to change out as I swap out my old Merc with the new perfomance 502? I have heard that the factory ignition limiter is set to 4500RPM's? Please remember I am on a budget..
As always... thanks fellas.
Jared
06-07-2006, 04:18 PM
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Re: Merc 7.4 330 to 502 Ignition change
Also, some hyd roller cams have steel gears and some cast iron gears. Steel gears require different dist gear. You need to find out what gear the cam has so you don't chew up your dist gear.
Hyd flat tappet cams all have cast iron gears.
Hyd flat tappet cams all have cast iron gears.
06-08-2006, 12:59 PM
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Re: Merc 7.4 330 to 502 Ignition change
buy a MSD or DUI well worth the $
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06-08-2006, 02:32 PM
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Re: Merc 7.4 330 to 502 Ignition change
I am trying to minimize cost as I am swamped as it is... so Yes I am trying to use as many parts from the old motor as possible. I also want to make sure that if I need better parts... I buy them. I am trying to be thrifty... not cheap.
06-08-2006, 02:37 PM
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Re: Merc 7.4 330 to 502 Ignition change
The ignition module is probably on the side of the distributor. It may list TBolt IV vs V, and will definitely have a part number.
I think the V will have a knock sensor and rev limiter.
The IV will be a simpler swap.
As others pointed out, some of the roller cams may have problems with the distributor gear. You can call the cam manufacturer about that part.
Gary
I think the V will have a knock sensor and rev limiter.
The IV will be a simpler swap.
As others pointed out, some of the roller cams may have problems with the distributor gear. You can call the cam manufacturer about that part.
Gary
