7.4L cam
#1
7.4L cam
Can anyone confirm what the stock cam specs for a 1988 7.4L should be. My service manual states 350/352 advertised and doesn't state LSA - but this seems crazy so I'm sure it must be a misprint.
Thanks
Matt
Thanks
Matt
#2
Registered
Re: 7.4L cam
Mad,
The data I have for a 1988 7.4 (330 hp - not Mag) is:
Lift int-.461 and ex-.479 Advertised dur int-.350 and ex- .352.
Duration at .050 is 214/218 degrees, the lobe separation is
115 degrees
Merc PN 437-4734
OR
The data I have for a 1988 7.4 (330 hp - not Mag) is:
Lift int-.461 and ex-.479 Advertised dur int-.350 and ex- .352.
Duration at .050 is 214/218 degrees, the lobe separation is
115 degrees
Merc PN 437-4734
OR
#3
MarineKinetics
Platinum Member
Re: 7.4L cam
Originally Posted by MadMat
Can anyone confirm what the stock cam specs for a 1988 7.4L should be. My service manual states 350/352 advertised and doesn't state LSA - but this seems crazy so I'm sure it must be a misprint.
Thanks
Matt
Thanks
Matt
You are correct, that is a mis-print in the manual. (Not the only one)
The correct spec are:
Merc #431-4734
GM# 3904359
278º/289º @ .006"
213º (214º)/ 217º (218º) @ .050"
.270"/.282" Lobe
.460"/.480" Valve
110º ICL
118º ECL
114º LSA
Bob
#6
Registered
iTrader: (1)
Re: 7.4L cam
Originally Posted by MadMat
Can anyone confirm what the stock cam specs for a 1988 7.4L should be. My service manual states 350/352 advertised and doesn't state LSA - but this seems crazy so I'm sure it must be a misprint.
Thanks
Matt
Thanks
Matt
The guys above gave you the right info. I have a little more info in my notes:
Standard Flat Tappet (oval heads)
.004” 287*, 302
.006” 278*, 289
.050” 214*, 218*
.200” 111*, 119*
Valve lift with 1.7 .460” , .480”
ICL 110 ATDC
ECL 118 BTDC
114 LSA
Last edited by SB; 07-13-2006 at 09:35 AM.