Early 302 can in a 351W

I got a Comp Cams hydraulic roller cam for my 351. I asked for a super mild low end torque cam. No one, them or I discussed exactly what engine the grind was designed for. In use it runs like crap. I used the 351 firing order in routing the plug wires. Could the cam be a 289 or early 302 type? That would mean a different firing order. I did tell Comp Cams the cam was going into a 351. They may not have had a milder grind for 351s, so to give me the mild cam I wanted, they had to sell me a 289/302 grind. The fact that the engine runs at all with 1/2 the cylinders not firing in order is surprising. Has anyone had this experience?

jckkys said:

I got a Comp Cams hydraulic roller cam for my 351. I asked for a super mild low end torque cam. No one, them or I discussed exactly what engine the grind was designed for. In use it runs like crap. I used the 351 firing order in routing the plug wires. Could the cam be a 289 or early 302 type? That would mean a different firing order. I did tell Comp Cams the cam was going into a 351. They may not have had a milder grind for 351s, so to give me the mild cam I wanted, they had to sell me a 289/302 grind. The fact that the engine runs at all with 1/2 the cylinders not firing in order is surprising. Has anyone had this experience?

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Whats the part number? Lift duration and LSA? If it starts with a 35-xxx-xx it is a 351/HO firing order. Also longer duration cam needs more timing and more static compression to idle decent. I'm running .550 lift and stockish idle smooth at 750 rpm.

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Yeah sort of not understanding why you didn't use one of the 20 or so 351 cams... But seeing as you say only half are firing, i bet the firing order is not what you thought for plug wire routing.

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If you have confirmed that the distributor plug wires and corresponding cylinder locations are correct, and distributor advance is correct to wire location, then I would try the early firing order to see if it runs normal. If no improvement is achieved, Improper Valve adjustment is suspect at this point.

I was able to get mine cranked but it ran like shit.

My Dad came by and switched it to the "other" sbf firing order and it ran perfect.

So yes it will run with the other/wrong sbf firing order.
Switch up and see Hoss.

I would just look up the part # and see the listed firing order.

If for some strange reason that is not available, pull of valve covers and see what intake valve opens after # 1...is it five or three.

I don't have the part # anymore. Neither does Comp Cams. At the time, I remember driving an Explorer and being impressed with the low end torque. For a truck it was far better combo than the Mustang HOs of the time. So the same grind in a 351 would of course be even better. The Comp Cams grind has more lift and steeper ramps, but the duration is very close to the F4TE cam. A smooth idle at 500 RPM and near maximum torque at 2000 RPM is the goal. The problem is, that the restoration shop is geared towards high RPM HP. Only the machine shop that blue printed the engine understood. No one checked the cam's firing order. I assumed Comp Cams heard me when I told them the cam was for a 351. It turns out they did. My FUBARed plug wire routing was just that. I tried the 289 and early 302 order with no improvement. Then when the 351 firing order was redone I found a couple cross wired pairs of plugs that were incorrect for either firing order. With that fix the engine ran as it should. If I had simply checked the wires one at a time the problem would have been found much sooner.

Glad you fixed it!