Just an FYI not to overlook what's in front of you more than anything. After putting finishing a 302 swap and a few test drives I had a bad vibration in the car when under acceleration, starting at about 40 mph. It came in waves and almost disappeared when I took my foot out of it. So I'm thinking... 1 Could I have screwed up with the flex plate balance? No, '93 HO motor=50oz imbalance. That's what's in it. 2) Ya know, I never made sure it was a later harmonic balancer. It was painted the factory gray like the rest of the motor, I assumed it was correct. Pulled it off Sunday to swap with one I knew was right. Turns out it was right also. Swapped it anyway because I was right there, no change. Didn't make an a$$ out of u and me this time! 3) Tourque converter messed up and out of balance? How often does that happen? Guess its possible, maybe PaulS woul know. Hold that thought, don't have another to try and don't feel like pulling the motor back out just yet. 4) What about that stupid aftermarket fan that came with the project? It spins pretty fast and has a wide rotational area. Let's swap with the one on the mustang...Holy Tacoma Narrows Bridge Batman!(look it up, it's awesome!) No more vibration!! It was like a different car! No more vibration! Could not believe the difference! Just something for you guys to keep in mind as a possible source of a strange vibration and to remember to take a problem one step out a time
Process of elimination is a major part of any diagnostic routine.This is a great example of how its done...
Just adding, if you have a 28oz and need a 50oz flexplate, you don't wonder if its wrong. It will rattle your teeth out in seconds at idle. I would assume the balancer would have the same effect. I've still got a mild vibration I've had since I got my car, and never have figured it out. Before I get'er going again, I believe I'm going to pull the axles. Just about the only thing I haven't checked yet.
Its been awhile, shes been in parts for a couple of years, but the main vibration is when you're on the road. It has a cyclic vibration in the engine, but no one else can feel it. Very subtle. I have replaced the main and rod bearings as a patch, vibration existed before and after. Gonna rebuild it completely once I get the car finished anyway.
might want to balance the rotating assembly...Of course it could allways be drive line or pinion angle... trans tailshaft support bushing ETC... good luck.If the thrust face on the crank is bad,all the new bearings in the world may not fix it unless you get an oversized thrust bearing.
I was already thinking that. I wanna have the option to turn it over 6250 without worrying about balance issues.
