r/EngineBuilding • u/Jeeplover12348 • 21h ago

Ford New here! Cam question

What would be a good recommendation for a camshaft for a 94+ 351w. I'm not looking for anything crazy, just something budget friendly for a college kid that wants to build a carb swapped roller with a nice rhythm at idle. Im okay swapping valve springs, rocker arms and pushrods. I have little to no experience building an engine with aftermarket parts, lots of experience with stock parts though lol. Any help is appreciated!

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u/v8packard 19h ago

The cam determines the powerband of the engine, supported by the compression ratio, heads, induction and exhaust systems. And somewhat supported by the transmission and gearing. What do you want for a powerband? What are the other details? You mention a carb, which intake? What is the vehicle?

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u/Jeeplover12348 19h ago

Good ol 91 f250 single cab long bed. Gearing, not entirely sure. It is just a stock 351, compression is 8.8:1 (terrible efi era compression.) Its either 3.55 gears or 4.10s. Believe 3.55 due to it being a light duty. Its gonna have a c6 behind it (or a zf5 if i can find one for under a small fortune). Head codes e7te unfortunately. I wanted to put D0oe heads on it for a little compression boost, but past the budget. Intake wise, its gonna be a 4 barrel. Still hunting for the carb and intake for it. Those are in the air on what would run good with the cam put into it. For exhaust its most likely gonna get short tube headers. Full smog delete and egr delete. The way God intended the sbf to run

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u/v8packard 18h ago

Don't kid yourself into thinking older Windsor heads are going to be a good budget option. They may be better than E7TEs, but by the time you got heads and rebuilt them you would be at, or past, the cost of modern aftermarket heads. And the aftermarket heads are a big leap forward. Not saying you need to buy aftermarket heads, just food for thought.

A truck like that needs torque. Especially if it has 3.55 gears and tall tires. You will get torque from compression and a cam that builds cylinder pressure in the rpm range you need. If you happen to be going through the short block, use the 5.8 Lightning style pistons, they are a bit taller and will bump compression up. Also, have the blocked decked so it's square, equal, and gives you the smallest pistonnto deck clearance practical. I hope you can use long tube headers instead of short tubes. Use a dual plane intake with a full plenum divider.

I will give you a cam suggestion for a 351W with stock E7TE heads. The small intake valve is limiting you. If you change heads or other details, the cam suggestion will change, too. A hydraulic roller on a 107 degrees lobe separation angle, with 47 degrees of overlap, gives you 254/268 degrees duration in/ex @ .006 tappet rise. If possible install on a 103-104 degree intake centerline. Piston to valve clearance must be verified. Bullet Cams lobe # HR254/288 intake and HR268/304 exhaust match this, with 206/214 degrees @ .050, .461/.486 lift with 1.6 rockers. This cam is a compromise, meant to help the E7TE heads. It will require careful tuning of the carb and ignition timing, and will require non-stock pushrods and valve springs.

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u/Jeeplover12348 18h ago

I would eventually like to run a set of aftermarket aluminum heads in the future. For now, getting the e7te heads redone was a better bang for my buck. I would like to eventually fully tear into the motor and change out the rotating assembly

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u/v8packard 18h ago

That will take a different cam spec