it has a 302 firing order and not a 351 firing order 1991 mustang BUT i found this... "Actually Competition Cams builds a cam for speed density sysytems but i need to know if it is 302 firing order or 351 firing order they build a cam for both. I was also told that the orange tiped fel injectors is an indicator that it is a 302 HO engine (not sure if this is correct or not). " doesnt really tell me much but could their be a cam that requires a 302 firing order that goes into an h.o. motor???
"Also, I think most performance parts (mainly camshafts) are made for the 351 firing order (aka, the 5.0 HO firing order, but the 351 was first with it). So IF there is an advantage to the firing order itself I dont know... but I do know that the 13726548 firing order is much more common in the aftermarket. Crank is the same either way if I remember correctly It isnt a big deal... just swap the plug wires on the distributor around to the new firing order if you get a 13726548 camshaft. " could this be the reason it doesnt have a 351 firing order???
All HO's had the 351 firing order, and will not run with the 302 firing order. If it was a 91 HO, it should be the 351. You can buy cams either way, 302 or HO, A 91 will also have the roller cam, if you pull the intake, it should have "XXX" cast into the lifter valley, it could just be a newer 302 with a roller cam, with 302 firing order, then it's not a HO motor. Ford trucks had roller cam engines, that are not HO's
As did the full size Ford, Lincoln and Merc cars, plus the 86-92 T-Bird/Cougar. The pickup/van 5.0 only had the 302 F/O roller cam for two years, then got the better F4TE roller with the 351 F/O order.
