Finally rebuilt my 302, engine is running great except for some metallic noise when cold and idling then goes away as it warms up. I'm pretty sure it's piston slap should I worry ? Frank 80 F-150

 

any noise on a rebuild is not good........
did you have the bore checked?
What did you do to it?

 

did you use forged pistons? cuz they'll make some noise when cold, and stop once they warm up.

 

Don't slap your piston that's cylinder abuse, Dr Phil is gonna call you, Why are you abusing this motor, you need to think about What you are doing mmkay!! If it is worth a gasket set to you I would open up at least one side and see what the bore looks like, Using a magnifying glass and a bright light to see if you got some wear starting. How many hours are on that motor? what kind of oil di you use to break it in?
I always recommend diesel oil, Run for a couple hours change oil and filter, cut open the filter wear gloves it will cut you up!! but is a good diagnosing tool if you see lot's
of metal that got filtered out further inspection might be in order. Run this oil change for a bit longer 6-10 hours and change the oil out leave filter in, Run this oil for a 1500 2000 miles, change oil and filter(cut open again) and refill with the type of oil you are
going to stick with. The diesel oil has lots of zinc and phosphorus which are extreme
pressure lubes and will prevent damage if something is a bit too tight or if there is a
higher ridge on a surface. The zinc prevents metal to metal wear if the oil can't prevent the parts from kissing. You want the first 3000 miles or so to be protected by
the zddp, You could use those oil additives that have the zinc in it (read the label) If
you don't like to mix different oils, But the diesel oil has more detergents and additives to keep dirt,wear particles and other junk in suspension to be filtered out!!

 

I've built a few motors with forged pistons, never had any noise.

 

you probably set your clearance's tight, also depends where the shop/he set his tolerances

 

Had a small ridge at the top of the cylinders, cut them out with a ridge reamer.Gave them a quick honing and then slipped in a new ring and checked the end gap.The specs. should be between .010 and .020 I had .024 I took a chance and put the original flattops back in when I should have at least put new ones in and yes I used 15w40 diesel oil for the break in. Guys you don't have to tell me I know I should have bored it .030 over I'm already kicking myself in the *** for not doing it.

 

It's at least better than replacing the top end with all new and not doing a thing to the bottom end, and wondering what that horrible knocking noise is!! Run some 20w50 until it get's too bad. Get a junk yard motor and either rebuild it or drop that in and pull your motor and rebuild the original one the correct way. Take your time and save to get the best you can afford, I know it's frustrating to have a vehicle sitting and not driving it it makes you rush and do stupid things. That's why I say get another one to drive while rebuilding!!

 

Fell on a GREAT deal over the week-end,bought a freshly rebuilt Mustang Hi-Po 302 from a friend of mines brother.approx.325HP for a really good price. (Installation included ) Now that should be Fun to drive. Will be taking your advice on rebuilding my original engine,in fact already have future plans for it.

 

find out what cam is in that motor and post the specs. most of the mustang cams wont work well in a truck due to making power way to hi in the rpm range.

 

Will be getting them tonight or tomorrow,I'll keep you posted.


Frank
80 F150

 

Which is better performance wise? Edelbrock 600 cfm or Holley 650 cfm


Frank
80 f150

 

CAM SPECS: Crane Cams Part no: 444231 Hydraulic roller

Valve setting: INT. .000 EXH. .000

Lift: INT. @ Cam 311 @ Valve 498
EXH. @ Cam 311 @ Valve 498
Rocker arm ratio 1.60

Cam timing: Open Close Adv. Duration
@ .004 INT. 28 BTDC 74 ABDC 282
EXH. 68 BBDC 34 ATDC 282

Cam timing: Open Close Max Lift Duration
@ .050 INT. 0 BTDC 40 ABDC 110 ATDC 220
EXH. 40 BBDC 0 ATDC 110 BTDC 220

Firing Order: 1-3-7-2-6-5-4-8 Recommended RPM Range: 1400-5200
Valve Float: 5800



80 F150

 

Engine is already in truck and is a solid runner.Will be upgrading the gears next.


80 F150