Need help troubleshooting engine vibration

I recently went through a big upgrade for my drivetrain including a new 347 crate engine and a T5z trans. The engine is from CHP and was balanced for 28oz, so I ordered a 28oz harmonic dampener and 157 tooth 28oz flywheel. Everything went togerther perfectly, but I get a bad vibration when the engine is running parked, it gets really bad when driving down the road. I pulled the trans and FW today and was hoping to find the FW mistakenly to be a 50 oz, but I'm pretty sure it is a 28oz unit, see pic below:



The part number stamped on the flywheel is FW-1600. I did a search and this appears to be a 28oz unit. So, my problems could be:

1)the engine was not balanced for 28oz like the paperwork says, but maybe 50oz or zero? Anyway to check this without tearing apart?

2)the new harmonic dampener is out of spec

3)the FW I have is out of spec and not accurate

One last thought I had was when I installed the Ford Racing King Cobra clutch and pressure plate, I did not use the locating pins (they weren't inlcuded) to align the pressure plate. Again, everything installed fine and I didn't struggle with alignment of the pressure plate bolts. Could this be the source of my problem? What else should I consider? I hate doing work twice, but man I want this fixed! Thanks guys.

mustangmike6996 said:

is the flywheel properly indexdea on the crank?

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Thanks for the response, I'll break this down with answers. The FW goes on only 1 way, bolt holes only have 1 alignment.

mustangmike6996 said:

is the clutch-pressure plate properly torqued (or convertor)??? in sequence?

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Yes, I followed the tourque sequnce and specs to the letter, checked twice.

mustangmike6996 said:

how are the motor mounts? is the transmission/bellhousing/ eingine properly aligned using factory service specs?

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Motor mounts are good, but not new. They appeared to be fine though. The bellhousing is a late model aluminum unit which matches the T5 trans. There aren't any adjustments to make on this, so I don't suspect this.

mustangmike6996 said:

how about the driveshaft and slip yoke being indexed and torqued or the correct length? is the slip yoke and pinion angle the same as each other?

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Since the vibration occurs parked, I don't think this is the cause. I put a new yoke on the original driveshaft and got lucky with the fit, didn't have to have it shortened. I did reindex the driveshaft 180 degrees and noticed the vibration while driving was better, so I think I have it indexed properly. Rear pinion angle is factory and the trans tailshaft is set by the trans cross member I purchased for the swap (Ron Morris unit). Nothing looks odd about the angle.

mustangmike6996 said:

is there an out of balance cooling fan? or drive accessory? it may be something simple and small?

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I'm running electric fan, but suppose it could be the alternator or PS pump. I am also using March billet pulleys. I will try to remove the belts and see if there is any change.

mustangmike6996 said:

before you have to pull that engine i would make sure all the mounts are properly algined and its not a poor install (not that i am saying anything bad about you/the installer) but there are many possibilities... if oyu take it to a shop that deals with an EVA (electronic vibration analysis tool) you can get the frequency reading in hertz and figure out from there what makes that frequency and what is out of balance..... i hope this helps just remember check doulbe check and triple check you can never be too certain.

let us know what the origin is and how you corrected it tho...

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I am the installer but no offense taken. I am pretty anal about everything I do and was very careful to double check everything I did. That said, I'm not beyond making mistakes of course. Not sure about an EVA, hopefully I'll locate the source before it comes to this step. I will be sure to update this post as I troubleshoot and correct this issue. One of the frustrating things for me was finding a couple of threads with the exact symptoms as me, but the post was incomplete and did not have the resolution.

D.Hearne said:

I think I'd suspec the flywheel. That's the first one I've seen with a welded on counterweight, other than automatic flexplates. Forget the alignment pins, I've run em without em too and not had problems. If you have a local shop that does balancing work, you can take the flywheel and balancer in to have them checked against known stock parts (match balanced) Stroker assemblies are balanced to 28oz due to the extra counterweighting on the cranks. You'd have to remove damn near all this to counterweight it to 50 oz. Look at a stock 50 oz crank and a 28 side by side and you'll see why there's a difference.

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Thanks for you insight D.Hearne. I have read many of your posts and respect your opinion highly. I have been suspicious about the flywheel all along simply because it was cheap in comparison to others. I got it new off an eBay retailer who seemed to be reputable. I think I paid $80 for this thing compared to the Ford Racing unit on Summit for $230. At the time I figured a FW is a FW, differences would be aluminum versus steel, but it's like anything I suppose, cheap parts are cheap parts. I may just order the Ford Racing unit just to know I have a quality part in there. I used top quality parts throughout except for this piece. I will call my local machine shop to see if they can check my parts before I order, that is good advice.

BB1966 said:

If the flywheel/HB check out call CHP and make sure the engine is really 28oz. If it was blueprinted or not it will be in the specs.

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I have the build specs which include all the balancing performed on my engine and it is 28oz. I did call CHP anyway a few weeks back just to see what they suggest and the tech suspected the FW as well.

GoinBroke said:

Make sure you have the right size pilot bearing in the end of the crankshaft or this could cause vibration also. Good luck!

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I bought a new RAM roller pilot bearing that was specified for a small block Ford, part# BA50M. The specs from RAM's site are:
OD = 1.379
ID = 0.672
Depth = 0.725

I don't recall having any issues with fit when I installed it. I used a hammer and socket if I recall.

Pbum5 said:

If you do choose to replace it.

I have a NEW 157 T 28 oz Hays Billet Steel flywheel that I will sell ya for less that the Summit Price shipped.

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Why are you selling it? Has it been installed or new in the box? What is the part# and price? Thanks.

Thanks for all the replies. I am going to go ahead and replace the flywheel and hope it resolves the problem. I will also order the pressure plate locating pins to remove that from the equation as well. Hopefully will get everything back together within the next couple of weeks and post back some positive results.

Well, my vibration problem has been solved. It did turn out to be the cheap flywheel I picked up off ebay, trying to save a hundred bucks. Let that be a lesson... Here are a couple of pics of the crappy cheapone versus the nice Ford Racing piece. The Ford Racing piece has nicely chamfered holes and machining looks top notch. Engine runs smooth as can be now. I wish I wasn't so lazy and would have finished the swap a couple months ago!