I have never “freshened” an engine before, the few engines I have built over the years have been overhauls with used components machined and the usual items like pistons replaced. Now I want to go through the $62.99 1991 Mustang 302 I bought for my Maverick trying to keep it cheap to free up money for a set of AFR165 (comp. package) heads. I will be running the stock cam and converter for now, with a bigger cam, looser converter, and steeper gears later as finances allow. I do not imagine the future cam selection will ever be one that is used much past 6000-6200 RPM. The car will be a toy, not my commuter. Of course I will measure and inspect everything, but assuming I find that the crank, rods, pistons, and bores are original and useable without machine work (other than a bottle brush hone) I have a few questions. 1) What brand of rings would you use on the stock pistons, Sealed Power? Original Ford? 2) Anything special to watch out for on these used pistons like a place where it is common for ring lands to wear (side etc…)? 2) What brand of bearings? 3) Would you change the rod bolts to new ones from ARP and if I do, do the big-ends need to be “re-sized” and how does this affect rod bearing selection for the un-machined crank? 4) What oil pump would you use for this engine using the stock Maverick pan and pick-up? 5) Any other advice?????????????
My $.02 IF upgrading the heads is your limit on mods, I would: -Use Ford rings -I'd look for stress cracks or hot spots on the pistons, top and skirts -I like Clevite bearings and Melling oil pumps -I would leave the rod bolts as they are, unless you are spinning it high If you change the cam, be sure to change the lifters as well.
-"I would leave the rod bolts as they are, unless you are spinning it high" Littleredtoy, What RPM can the stock bolts take? (ie. what do you think is high)
I rebuilt mine with stock rod and main bolts and bounced it off the limiter(6250) on several occasions without issue. Ive seen multiple blocks split and rods themselves break, but the bolts were still intact. They are not the weak link in a roller motor. With that in mind, dont come knock on my door if by some strange luck yours do let go LOL As far as rings I used steel replacements from Autozone in mine. Be careful using chromemoly rings if you arent planning on taking the block to a machine shop. Getting them to seat can be an issue if the cylinders arent prepped correctly. AC
I agree with him. Unless you are going over 6,500 on a regular basis, you will probably be fine. I have ARP rod bolts on reconditioned rods, cheap insurance. I have heard that the roller motors use better stuff than my old non-roller '74 302 used. I have seen hopped up 5.0's, with stock bottom ends last a good while. Again, without many more mods, you will probably be fine. Seth
Are the rings and bearings worn? I believe the 1991 has forged pistons so try to retain the factory pistons. Does it need to be freshened? Just thought I would ask!
