4v heads on a 2v motor?

joshuaw3

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I have a 98 gt with the stock 4.6 2v in it and I was wondering if I could swap 4v heads on it from 03 Mach 1/ cobra. Will that work or not?
 

96blak54

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Yes it will work! Source the intake, front cover, valve covers for plug wires, fuel rails, cobra alternator(cause a thick old Gt alt wont fit the intake,...its gotta be a thin cobra alt) exhaust logs. Should work real good....now go get it all and swap. We're here to help out, so post lots of questions and post lots of pictures of your swap.
 
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joshuaw3

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Yes it will work! Source the intake, front cover, valve covers for plug wires, fuel rails, cobra alternator(cause a thick old Gt alt wont fit the intake,...its gotta be a thin cobra alt) exhaust logs. Should work real good....now go get it all and swap. We're here to help out, so post lots of questions and post lots of pictures of your swap.

Well here's the thing I found a guy locally who says he has a 4v 93 mark viii motor with 03 navigator heads which are the same as the Mach 1 and cobra heads so should I just get the whole motor and swap it or just do the heads? And where would I get all that stuff you said I need? If I swapped the motor what would I do about the computer do i need a new one or will it work just fine with a tune?
 

96blak54

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The navigator heads are navigator heads ...and the mach1/cobra are cobra heads. If the heads are in fact navigator heads they will still work but will have low torque reproduction compared to any other head, assuming a normal intake will be used.
Sourcing the other parts from junkyards or classifieds works
 

ft_nox

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Just being nosey.. would he need a new computer or a tune to make the most of the swap? Also, could aftermarket rails be used?
 

96blak54

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Key word here is "most". It'll run with out the tune with all the gt hookups, but to gain the most a dyno tune is a must.
 

96blak54

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Good point. The heads should come along with its original cam timing chains. And your 2v chains will work also
 

03DSGGT

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Won't just swapping the heads kill the compression? I thought the 4V cars have -3cc piston dish compared to the NPIs -10.5cc....
 

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