What a sad state of affairs. Had a new engine built. All the best. Procharger Stage 2, Diamond blower pistons, stock crank, titanium rods, ring landings lowered, Diamond blower rings, all ARP studded hardware, Comp cam & springs, ATI super damper 8 rib serpentine setup, Siemens 60# injectors, Racetronix custom dual fuel system by Lonnie's Performance, speed density tuning by Formato, Clevite race bearings, Centerforce dual disk clutch, pressure plate and flywheel (matched), Snow Performance methanol injection.
The engine goes from the machine shop to the installer, it all gets installed...bad vibration@ 1800 on up the scale. Worse @ 1800 to 2500. NOW, I'm asked "did you have the engine balanced"? Nice time to ask me! Hey, I never professed to be a mechanic. I'm just a guy with a wallet trying to trust people. So, we remove the engine again and take it back to the engine builder. I expressed my displeasure to this group, as I would have expected to have been asked " Would you like to balance the engine"? I think that's a reasonable question. Nonetheless, he balances the engine completely ( a very detailed process ) according to the Centerforce literature all of the clutch components are zero balanced. However I brought the clutch to the balancer anyway. We reinstall the engine and guess what? The vibration is still there.



I am at wits end, have no idea what to do next. Car runs like a scalded dog @ 15 lbs of boost. Don't have Dyno numbers yet, but expect them to be in the 700+ wheel category.

Searching for the next step? Please return me to my sanity!

 

I would think a good engine builder should be at least able to put it on a test stand first.

Sounds like something I don't want to go through.

Your right about trust.

 

So you have a bad vibration in the engine, and you are getting into the boost? Well...until you get the vibration resolved...stop doing that. You did not mention what type of engine it is i.e. LS1/6 etc. Also, how does it idle? Any vibration at idle? Typically, if the clutch assembly is out of balance, you will know it as soon as fire it up.

 

Torque tube related?

 

I was thinking torque tube also.

 

Is the vibration there with the drive train in neutral and the motor just revving?

 

Many years ago after going through a couple of bad rebuilds with my 68's 327-350, I called the local Corvette shop to ask about building a smog-legal powerhouse of an engine. He said something like,
"You know, we can pick all the best components and build what should be a great engine, but if I were you, I'd buy a (documented HP-output) crate engine that was assembled at the factory. This way, I can guarantee you that you'll have a 100,000 mile + engine in which EVERYTHING works well together.
Yes, there are some shops that crank out a reliable and potent powerplant everyweek, but they are very hard to find. Take my advice - get the crate motor and go fasy; it's as easy as that!"

Well, he was absolutely right. My ZZ3 C3 was a rocket that never gave me a headache.

Anyway, I do know how you feel and it is VERY frustrating. Have patience and try to isolate what could've been done wrong. SOMEONE has had the same problem; hopefully, he will chime in.

 

Your sig shows a '98. That's alot of years on the rubber couplings in the TT, especially with a boosted LS1. Are you still running the original rubber ones?

 

if it comes down to it unfortunetly you will have to take the motor apart and start over. you say you balanced the engine? when my shortblock was put together the rotaing assembly was balanced before it could be installed in the block. was this done to yours?


i would take it here and they are in tampa.

http://www.revxtreme.com/

 

This vibration in probability should not be coming from the engine. The engine was perfectly balanced. I can demonstrate the vibration sitting still with the car in neutral or in gear, clutch in or out. Starts around 1500 rpm then just changes as the rpm increases.

 

Yes

 

Yes the original ones are in the car as far as I can tell. But this happens as I said, clutch engaged, or not, in gear or not. Doesn't one of those testing scenarios take the torque tube out of the equation?

Thanks

 

The engine was removed a second time and the complete assembly was balanced. The crank, the bearings and rings, the rods and the pistons. P.S. I've had very unsavory issues with the shop you proposed, but thank you regardless. I have the balance sheets showing the before and after readings. All components are @ zero. I'm leaning to removing the clutch and testing it for balance and closely checking the TT components just to be sure. There may be an issue with the installation of components and the procedure utilized. Anyone can make a mistake. Sometimes a different set of eyes are a help. Everyones participation is an excellent help and I appreciate each and every one of you. This is what makes this an exceptional forum with the right type of members.

Keep the ideas coming.

Thank You!!

Thanks

 

If you are for sure the motor and clutch/flywheel are NUETRAL balanced (make sure everytign has a nuetral balance to it - some Ford motors are offset balanced, for what reason I have no idea), then I would start checking the motor mounts.

 

In days gone by, the first thing I would have looked for is crossed wires. And I'm guessing that you've ruled out miss fire.

Anything in the rotating assembly could cause the problem. This includes the flywheel, clutch, harmonic balancer, blower drive and blower itself. Since you've pretty much ruled out the clutch/flywheel along with crank/rods/pistons because of the balance job, then check to be sure the harmonic balancer is on correctly. While you're at it, check to see that the flywheel is installed correctly and is running true(I have seen them slightly cocked on the crank).

Easy way to check blower is to simply take it off and see if the engine runs smoother.

You might check around to see if anyone has any vibration analysis equipment. It's usually tough to do anything with a recip but with a simple out of balance condition, they should be able to narrow it down for you. Might be better than hit or miss.

Good luck.

 

I will be tending to the proper installation of the crank pulley and the clutch. I am suspect of the quality of the work that has been performed sadly enough. I am having a new fuel system designed that should be finished this week, then the search will continue. I will not be deferred until I get to the bottom of this. I will post all procedures for the use of all. Thanks again.

 

If you have access to EFI live I would take a real long data file to see what the heck is going on.

Could even be timing related.

 

Please explain, what is EFI?

 

EFI Live is a tuner program for LS based engines, similar to HP tuners or LS1 edit.

 

I be it's a bad motor mount.