Advancing Cam 351W Truck Engine

I am building a 351W for a truck, it is a 96 roller cam engine with stock short block. I am adding GT40 heads, 1.7 roller rockers and long tube headers. It is going in a 91 truck with speed density EFI and will be for towing only. No high RPM stuff, 5K will be it's max with a 4,500K more likely so my question is would you advance the cam a few degrees to pick up more low end torque, I know this worked on carb stuff but I'm not real EFI smart. Just give me your opinions good or bad.

I would not do it. These engines are not retarded like the 70's emissions stuff and seem to run pretty good in stock trim, at least my 5.0 95 truck does.

Find a good used O.E.M. Mustang 5.0 GT hydraulic roller cam. or a new cam designed especially for a "speed density" system, even if you convert to a "Mass Air" system later.

For those heads and a slightly larger camshaft you WILL need to increase the fuel pressure by about 10%.

I already have a cam from an Explorer courtesy of Whitefield....thanks again whitefield....thanks for the advice guys appreciate it

plowboy34 wrote:I already have a cam from an Explorer courtesy of Whitefield....thanks again whitefield....thanks for the advice guys appreciate it

Explorer camshaft :
F4TE-6250-BA
256/266 SAE duration - .264".280" lobe lift - 116 lobe separation; 118 intake lobe centerline

Original Mustang 5.0 HO cam:
E5ZE-6250-AA
266/266 SAE duration - .278"/.278" lobe lift - 115 lobe separation; 115 intake lobe centerline

5.0 HO cam with revised intake lobe, (less NOX emissions):
E8ZE-6250-AA
276/266 SAE duration - .278"/.278" lobe lift - 115.5 lobe separation; 116 intake lobe centerline

5.0 Cobra cam:
F3ZE-6250-CA
270/270 SAE duration - .282"/.282" lobe lift - 115 lobe separation; 121.5 intake lobe centerline.

It's "almost" a lightening engine . Like Randy said install the cam "straight up " on the gears as most of them ( like your cam) have the advance ground in.

Great info Randy thanks, I kinda figured these EFI engines were different but wasn't positive. As I said I am pretty much EFI stupid, I know enough to be dangerous.

gt350hr wrote:   It's "almost" a lightening engine . Like Randy said install the cam "straight up " on the gears as most of them ( like your cam) have the advance ground in.

NONE of those camshafts I have listed are ground advanced from straight-up; most are retarded a degree or so.

plowboy34 wrote:Great info Randy thanks, I kinda figured these EFI engines were different but wasn't positive. As I said I am pretty much EFI stupid, I know enough to be dangerous.

That first 5.0L H.O. cam was used with a carburetor as well as F.I.

gt350hr wrote:   It's "almost" a lightening engine . Like Randy said install the cam "straight up " on the gears as most of them ( like your cam) have the advance ground in.

H'mm I thought I said half of that and did not see were Randy said it at all? Oh Well. Did those valves get lost, they never showed?