XP/GT heads on 1984 Johnson 185Hp

imported_Dalew

Recruit
Joined
Jun 30, 2006
Messages
5
I have a 1984 Johnson 185Hp. Completely stock with std bore and fresh rebuild. Would like to put 1988 GT/XP heads on it. Would this require a jet change? Timing changes? Is this a good upgrade? Thanks in advance
 

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Re: XP/GT heads on 1984 Johnson 185Hp

The 185 is the same bore as a 150. If your heads are from a 150 GT/XP, should work. If your heads are from a 175 GT/XP, the bore is larger and the heads may not fit on the 84. If your compression goes up from the change, I would fatten up the jets somewhat.
 
Top