Need a cam recommendation for a Ford 302 HO

[Turbochad]

91-95 HO:
Lift: .278 intake, .278 exhaust
Rocker Ratio: 1.6
Duration: 276 intake, 266 exhaust
Overlap: 39 degrees, 19.51 factor
Lobe Center: 116 intake, 115 exhaust
Ford P/N: F1ZE-AA (91-94)

Don't know if marinized uses a different cam however.

​Anyone know if this vintage and type motor (HO) has roller or flat tappet lifters? I cant find it online and my motor won't be opened up for a few more days.

John C

It's a flat tappet motor.

[turbo2256]

If it is a flat tappet motor it should be easily converted to a roller tappet motor as it should have the mounting bosses for the spider needed to hold down the anti rotation yokes for the roller lifters.
Heads are most likely E7 heads. E7 heads as cast flow around 140CFM max. I do have a set of E7s professionly ported that flow around 220 at .500 lift (have been considering selling) actually flow better than many of the aftermarket stuff do to smaller ports and higher air speed and size of the 302.

With a rather restrictive lower intake and lopo upper and a stock HO cam it pulled 270 ft lbs at 2400 RPM peaked at around 300 ft lbs around 3600 RPM at 4800 was still in the 270 ft lb range. would have done a lot better with a torker II intake and a cam with no more than .500 lift. I would recommend these or a set of GT40s even over just a cam change. Also have a set of 1.7 Crane / ford Motor sport rockers a couple spiders for roller lifters no yokes or roller lifters though. The heads were set up with GT40 valves but just refeshed with Ferrea 1.9 / 1.60 valves.

[John C in PA]

Well, there you go. 50% say that 1992 used rollers, 50% say flat tappet. I'll have to wait for the top to be pulled to confirm. The heads are replacements by the PO so I need to check them.

Chad, what carb and cfm? How many revs are you pulling? How were the sea trials?

I appreciate the real-life input.

John C

[turbo2256]

I dont recommend vacuum secondary carbs for marine use on a rather fast boat as if the throttle is shut down quickly the quick shutting of the secondary's could shove the bow into the water.

http://www.quickfueltechnology.com/carburetors/marine/ These are some of the best on the market today

Should mention the dyno run was RWtorq readings with an auto matic figure a 25% reduction over what flywheel readings would have been.

[John C in PA]

John, I have the the same motor as you. The factory heads are not GT40 or GT40P. i don't remember the casting but basically they are junk. I put in a 10350701k Lunati cam and Edelbrock performer alum heads this winter. I just put it in the water yesterday for the first time but the motor feels really strong. The cam seems really good for marine use.

What length boat is yours? I wish I had that much room up front in my 16.

John C

[John C in PA]

I dont recommend vacuum secondary carbs for marine use on a rather fast boat as if the throttle is shut down quickly the quick shutting of the secondary's could shove the bow into the water.

http://www.quickfueltechnology.com/carburetors/marine/ These are some of the best on the market today

Should mention the dyno run was RWtorq readings with an auto matic figure a 25% reduction over what flywheel readings would have been.

I like their carb prices but I don't see a 450 CFM model. (Holley is adamant on that CFM for a 302 unless a big cam and other mods are done too.) Also, if you chop the throttle on either type of secondary actuator, the boats gonna dip in the bow. My thoughts are rather toward takeoff. You can't rev up a boat in neutral like a car with the clutch in or against a high stall converter. That's where mechanical secondaries work.

Vacuum secondaries should kick in when the vacuum is low and the motor needs more fuel.

John C

[turbo2256]

I have been building engines for over 45 years for cars , boats , street strip, drags, circle track, road course, economy, trucks. I look more towards how big a prop can be run more than worry about RPM in a boat. Max power in a build such as I SUGGESTED WOULD be 390 HP at around 5600 RPM which dosnt mean that would be peak RPM.

[DOUBLE DD'S]

listen to tmdog,,give bullett a call..they know their ****,,tms 384 pumpedc out over 500 hp and same as torque goes..as for me i use a extreme marine 278 and i wing mine past 5600....

[Turbochad]

What length boat is yours? I wish I had that much room up front in my 16.

John C

John, mine is a 16 also. The reason it looks bigger is that at some point a previous owner cut the panel in the front of the engine compartment so you can remove it to work on the motor. It is tight like yours when installed.

[Turbochad]

Well, there you go. 50% say that 1992 used rollers, 50% say flat tappet. I'll have to wait for the top to be pulled to confirm. The heads are replacements by the PO so I need to check them.

Chad, what carb and cfm? How many revs are you pulling? How were the sea trials?

I appreciate the real-life input.

John C

I am pretty certain that all of the OMC 5.0HO blocks are non-roller. Shop manual says so and Mine was. I had a 450 Holley vac secondary on my stock motor and now with all the goodies I put on a 600 Holley vac secondary. I will know more after this week but in the first run it pulled the 20P prop at 5k easily at 5500ft altitude. I have a 21P on for this week at Bear lake in Utah at 6,000ft elev. I am hoping for high 60s at 5,000ft. I would like to replace the manifolds for hi tek headers next, maybe this winter.

[mattyboy]

all the info I have seen is that the Ford 5.0 L HO went to a roller cam in 85 my 87 is a roller that doesn't mean that OMC didn't do something different

the heads on a HO should be different from a LO motor and it will have the 351 firing order

they were rated at 200-225 hp over their lifespan basically the same as HM was getting out of the 302 in the 60s 70s they just marinized what the car world had at the time


I would be leary of trying to build an old motor with just an upper upgrade cam and intake without worrying about the lower end as well.

depending on how major the reason for pulling the motor is and weighing it against the remaining boating season.

drop in turn key replacement fords can be found for 4-6 k and a nice 383 sbc with exhausts can be found for around 6k which should bolt up to the cobra

ford been there done that never again


some choices for discussion sake from long blocks to turn key


http://www.ebay.com/itm/NEW-REMAN-FO...lWjV4B&vxp=mtr



http://www.ebay.com/itm/NEW-REMAN-FO...lWjV4B&vxp=mtr

http://www.ebay.com/itm/NEW-Volvo-Pe...xWU~Ve&vxp=mtr

http://www.ebay.com/itm/BluePrint-MB...NW3ymV&vxp=mtr

[John C in PA]

all the info I have seen is that the Ford 5.0 L HO went to a roller cam in 85 my 87 is a roller that doesn't mean that OMC didn't do something different. The intake manifold may be off today. That will confirm the lifter type.

the heads on a HO should be different from a LO motor and it will have the 351 firing order. Got that info in my searches.

I would be leary of trying to build an old motor with just an upper upgrade cam and intake without worrying about the lower end as well. I'm not looking for major HP increases. just a little. As regards the lower end, the motor spins up to 4850 with my prop and sounds fine. I'm not willing to exceed that RPM without looking at the crank.

depending on how major the reason for pulling the motor is and weighing it against the remaining boating season. Hopefully I find out today. If damage is minimal, there is still time to order a manifold and 4 barrel carb.

drop in turn key replacement fords can be found for 4-6 k and a nice 383 sbc with exhausts can be found for around 6k which should bolt up to the cobra. For reasons important to me I am not going to replace the motor unless I trashed it. In that case, my season is over.

ford been there done that never again Yeah, well

Thank you personally Matty for a reasoned, non-know-it-all reply.

John C

[John C in PA]

John, mine is a 16 also. The reason it looks bigger is that at some point a previous owner cut the panel in the front of the engine compartment so you can remove it to work on the motor. It is tight like yours when installed.

Pretty radical move. I kinda thought so when I saw the tie-in plates on either side of the opening. Do you think any stiffness was lost?

John C

[turbo2256]

E6 heads were the non HO heads most of them could be found on grand marquis and crown vicks.

[John C in PA]

The heads had been replaced by the PO. I'll confirm what's on there soon enough.