Merc 7.4 330 to 502 Ignition change
#11
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Re: Merc 7.4 330 to 502 Ignition change
I Just Put The 502/502 Cam In My 330hp And Had To Change The Dist. I Would Recomend Doing So. The T-bolt Iv Should Be Fine. If Not I Think I Have A Msd 6m-2 Around Here I Could Let Go Cheap.
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Re: Merc 7.4 330 to 502 Ignition change
Originally Posted by Longrange4u
The Merc 330 was out of my 96 22 Scarab... As for the Cam its the 502/502 crate cam
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Re: Merc 7.4 330 to 502 Ignition change
Yeap... I have already tapped and moved the knock sensor to the new block so it sounds like you guys are on there (as it there was a knock sensor on my old block that I relocated).
By U... I may be intrested in that MSD anyways... could you PM me with info?
LT1.. wow, Now you got me thinking about that Cam... Is anyone else familar with this problem too?
By U... I may be intrested in that MSD anyways... could you PM me with info?
LT1.. wow, Now you got me thinking about that Cam... Is anyone else familar with this problem too?
#14
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Re: Merc 7.4 330 to 502 Ignition change
Originally Posted by Longrange4u
Yeap... I have already tapped and moved the knock sensor to the new block so it sounds like you guys are on there (as it there was a knock sensor on my old block that I relocated).
By U... I may be intrested in that MSD anyways... could you PM me with info?
LT1.. wow, Now you got me thinking about that Cam... Is anyone else familar with this problem too?
By U... I may be intrested in that MSD anyways... could you PM me with info?
LT1.. wow, Now you got me thinking about that Cam... Is anyone else familar with this problem too?
AS FOR REVERSION I AM NOT TOO WORRIED B/C MY NEW EXHAUST HAS A WATER TRAP AND WATER EVAPORATION POCKETS.
#15
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Re: Merc 7.4 330 to 502 Ignition change
A 1996 7.4L low output engine would have a thunder bolt V ignition with a rev limiter at around 4800rpm. You will need a different ignition module.
Try to get your hands on one from a 454Mag or 502Mag if you don't want to spend the $$ for an aftermarket ignition.
If your 7.4L is/was a Gen VI roller cam engine, the distributor gear will work in the new engine. If the 7.4L is a Gen V with a cast flat tappet cam, you will need a new gear.
As for the ZZ502 cam, there has been lots of debate how it is not a great marine cam, however, there are many guys running them with success.
Try to get your hands on one from a 454Mag or 502Mag if you don't want to spend the $$ for an aftermarket ignition.
If your 7.4L is/was a Gen VI roller cam engine, the distributor gear will work in the new engine. If the 7.4L is a Gen V with a cast flat tappet cam, you will need a new gear.
As for the ZZ502 cam, there has been lots of debate how it is not a great marine cam, however, there are many guys running them with success.
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Re: Merc 7.4 330 to 502 Ignition change
By U... got it thanks. I am considering on springing for the CCPerformance marine package for $699 that includes the Marine MSD ignition mod, MSD rev limiter, billit marine dist... etc.
Pat... Good info... I am thinking more and more that I just need to spring for the MSD setup. Any thoughts?
Pat... Good info... I am thinking more and more that I just need to spring for the MSD setup. Any thoughts?
#17
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Re: Merc 7.4 330 to 502 Ignition change
Originally Posted by Longrange4u
By U... got it thanks. I am considering on springing for the CCPerformance marine package for $699 that includes the Marine MSD ignition mod, MSD rev limiter, billit marine dist... etc.
Pat... Good info... I am thinking more and more that I just need to spring for the MSD setup. Any thoughts?
Pat... Good info... I am thinking more and more that I just need to spring for the MSD setup. Any thoughts?
If I was in your shoes and new is the call, I'd buy a DUI unit. $300 gets you a new distributor with a built in coil ready to drop in. Another $130 if you want to add on a rev limiter.
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Re: Merc 7.4 330 to 502 Ignition change
Originally Posted by Longrange4u
Well I went DUI for the Dist and rev limiter... I hope this is worth the $$$... any tips on install?
Thanks