High RPM vibration w/load

MPGmustang

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just one problem after another... someday It'll be perfect...

so I really don't know but I'm having high RPM vibrations mostly +4000rpm to where it really shakes the car bad. I don't like this. IMO, using the butt-o-meter, the vibration is getting worse over time... so I've been taking it easy as a precaution.

what has recently changed:
from 4cyl t-5 to v8 t-5
new ring gear
350cfm holley direct mount
new lifters (installed 1 month ago, ran 2 days then sat for 3 weeks before being ran again)
HID head lights (halogen just wasn't bright enough)

I have a few idea's of why it's bad, just havn't had time to check yet...
Timing, wrong timing can cause alot!!! don't i know it.
fouled plugs, too big of carb? misfire'n w/load +4000rpm???
lifters? because they sat for 3 weeks, or I didn't break them in properly (I just drove the car)
imballance in 3-finger pressure plate (4months ago I broke a clutch and the center grinded area's of the PP, 1/4 inch in, this could be an imbalance and as a precaustion I ordered a new diaphram PP to get rid of it just in case, it just came in today)
guide bearing came out? I made it really stuck in, so I hope not
ring gear made flywheel imbalanced, if so I'll take it down and resurface/rebalance it and install the new PP
imbalanced t-5 trans? (can one be rotationally imbalanced?)

these are all I can think about, I didn't have vibration earlier so it must be something related to what I have changed... Any other insights of what might cause vibration please let me know, I wanna go re-dyno with confidence. I'll be checking the timing and plugs tonight as it's quick and easy.

Thanks
Richard

I feel like I'm very close, it's nice to have car back on the road and if I can pin-point it I might stay on the road or only be down for 1 day.
 
Richard, does the vibration occur with the shifter in neutral & not moving, but just reving the engine to over 4 grand??

If no vibration are the engine mounts tight, trans mount??

Check the u-joints at the yoke & pinion flange.

If its the original 2 piece driveshaft & the u-joints don't line up that will cause a vibration cause the joints are out of phase.

Are the bell housing bolts tight.

Jack up the rear end & put the trans in 4th gear & brings the engine to 4 grand & see if the vibration occurs with the rear wheels off the ground.

If not check the ignition system for problems.

Check the fuel pump for proper pressure & volume. Bill
 
Woodbutcher, I have confirmed the HB to be on TDC when I had the head off checking the cam timing, to my veiw it does not look like it's slipped and in any rate I havn'et changed or touched it since it was running smooth so I have taken that factor out of the running possiblities. but it is a good thing to consider.

wsa111,
I do have vibration when in neutral, I have vibration when clutch pedal it pressed,
for the drive shaft it does not seem to be speed related, only RPM related, so I'm thinking it's not after teh tranny and probably not even the tranny
to my knowledge everything was assembled correctly, I was there the whole time.
the vibration is to the rear wheels @ 4k rpm no matter what gear. 4k rpm...

I'm thinking my 3finger is just giving

I have check the plugs lastnight, all light tan, light brown, few dark brown but no build up, plugs are look the best since I have owned the car. timing was spot on where it was, 15*, for now I have retarted the timing to 8* to help not hurt the engine.
the fuel pump has never been replaced, it's been on the car since I have bought it. but I can't see that as a vibration issue as bad as this is.

My conclusion is as it was before, it's somewhere between trans and engine. maybe it's an alignment issue with the engine to trans? my old trany destroyed the inputshaft due to the guide bearing falling out, what if that's not all that was the problem.
 
I have nad driveshafts and cluthes that caused the vibe's like that before, was there any change to driveshaft? Edit: Dose the input of the trans go into the pilot bearing far enough if its not keeping it center to the crank centerline would cause vibe’s too. Not done one like yours but on some adapted trans swaps have had to use an custom pilot bushing to make it work.
 
Richard, you have the problem isolated to the clutch, flywheel or engine.

Remove the trans, clutch & then start the engine to see if you have a vibration. If you still have the vibration get the flywheel balanced. Also remove all the drive belts & start the engine to see if its something in the alternator, water pump or fan if so equipped.

You're close Columbo, good luck. Bill
 
I have had pressure plates that were unbalanced. Also, if one bolt on the PP falls out, that would be enough to get a vibration like that.

PITA, but I think you should do what Bill suggests, and if the vibration is still there, its probably the flywheel.

Long shot possibility, but are all six pistons and rods the same? There's enough weight difference between early and late rods to do this too if they got mixed.
 
Thanks for your reply's and insights/suggestions, I appreciate it.

Jack/Bill
I figure since I'm in there I might as well get the FW resurfaced, I have a new PP (diaphram style) and new clutch that will be going in. and since it's getting resurfaced I figure I might as well re-balance the blasted FW. I don't see why not. I'm just tired of taking it apart and :bang: every time just becuase I'm little rushed to get it back on the road.

if I take off the trans and place the engine on a jack (with wood block) to lift the rear of engine wouldn't it just vibrate even worse? even if it was balanced??
IDK but thought I'd ask.


Bubba here is a fitment pic of the guide bearing, I can't take out the bearing without taking extreme measures :twisted: , I make it this way as the previous bearing just fell out on it's own.
 
From that picture looks like the input shaft is not into the pilot bearing enough and that the pilot is not seated into the crank shaft far enough also. Sometimes a trans adapter plate for a bell housing the trans gets moved back enough to cause that. If the input shaft were not supported by the pilot the clutch disk won’t stay in center the wobbling around off center would give you the bad vibes and would take out the front trans bearing too. There are spacers made to reposition the pilot to fix that or if you have a good machine shop in your area it could be easily made on a lath other wise you might try Wilcox.
 
well that pic of pilot bearing was before I pounded the crap out of it, it was tight at one time. but I guess not good enough. as it was not 'stuck' when I took out the tranny u could see the bearing already falling out.

I got a brass bushing that fit, scuffed up the inside with a flat head screw driver, then used thread locker on the brash bushing to keep it in, I doubt it will last long but I COULDn't get it out when I tried last night, I even tried to pry it out, so I know it's in there good, I bet after a while it will proabably come out. but I hope not soon.

the vibration is gone :D , I can rev back up to 6k easily and comfortably. :D

I got the Diaphram PP on and HOLY CRAP I hate the feel of the pedal, Who said it was easier??? it sucks, it's either on or off, not inbetween. and it feels like i'm "slamming" it in gear all the time. the foot action SUCKS IMO, I don't know why anyone would want to have this feeling as a clutch. it's goign to be alot worse in traffic and I have to relearn how to clutch the darn flipping car, I hope it becomes easeir over time but right now my leg is sore, and I've only had it together for less than 24hrs... :bang: :thumbdown:

side note, I didn't know I had that much power in the rpm area's, the new PP really keeps that clutch from moving, I wonder if the old 3 finger pp was letting the clutch spin some or was just not tight enough, I know when I took the tranny out the 3 fingers were loose and I could move them forward/back about 1/4-1/2 of an inch, I bet this was the vibration.

one last question, is there ANY PLACE that makes a USA clutch? I'm tired of sign these KOREA clutchs that only have 4 rivits holding them together.
 
"...I hate the feel of the pedal..."
Isn't that Y they came up w/hydraulic clutches? U need a slave (cylinder) in more ways than one. 3 & 4 fingered can't add one? you can add to Diaphramic?
Congrats on 'no more bad vibes'. Hope this part wrks out as well...
 
one last question, is there ANY PLACE that makes a USA clutch? I'm tired of sign these KOREA clutchs that only have 4 rivits holding them together.

I used to get my clutches custom built for racing applications at Mcleod (also bilet flywheels) they are still in busness though not sure if under the same ownership and location. Back than I always would use a three finger and they could build them with as much spring pressure as you needed. Also used Hays and a few others too. http://mcleodracing.com/categories/Clutch+Discs.mcl

I know of a locale rebuilder that can rebuild to stock spec's if you have a core if your bell has the room and flywheel can be drilled you could go to a bigger V8 size clutch.
 
"...and flywheel can be drilled you could go to a bigger V8 size clutch..."
Like to hear more about that if it's OK.
If not I'll go tp PM,
Thanks
 
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