Recently purchased an E303 cam, do I need to use the 302 firing order or the newer 302HO/ 351 firing order? Other than that, is there any other problems associated with putting this cam into a "standard 302 roller" block.

BTW it's going to be a carb car so I don't have to deal with the injector order.

 

Pretty sure you use the ho firing order. Being its designed for a roller motor. I use to have a b cam in my carbd roller motor and that's the firing order I used, and it should just go right in with out a problem.

 

Yes, the HO timing. We just built up a mild street motor for my son's Fox mustang. Sounds very much like what you are trying to do. E-303 cam, Performer RPM intake, mildly ported E7 heads, 600 cfm carb. We just put it on the chassis dyno and made 256hp to the rear wheels. Will probably get a little more out of it when we finish tuning.

 

Was it originally a roller block? Do you know what year the block is? As long as it has the provisions for the roller cam block you'll be fine.

 

Yeah, it's a roller block (about 90 or so)
While we're on the subject, if you did have a fuelie with the old firing order, couldn't you just extend the wiring and swap injectors to change their sequence as well? I mean the injector doesn't know which cylinder is firing.

 

I put an E303 in an 86 Country Squire Wagon (Roller /302) that had the non HO firing order. Just wired it up with the HO firing order and ran like a champ

How ever,.. I also converted the car to carb while I was at it. So I do not know if the injection system will fire in the same order as the ignition once changed. If the ECM is for a roller then I dont see where it would be a problem. But EFI is not my expertise,.. so dont hold it against me if it doesnt work.

 

It's batch fire side by side. Injector wiring doesn't matter

 

Thanks, that really sucks though.