JohnKoaWood

Whats at risk by doing a balance shaft delete?

88 N/A, daily driver 99% highway...

fortysixandtwo

You're going to get a very wide variety of answers on this one. Some will say your engine is going to vibrate it's self apart, crack pickup tubes, loosen all the fasteners, the earths magnetic poles will switch....etc. Others will say no problem at all beyond a little extra buzz at sustained speed and even some have not felt any difference.

I have deleted them from my car, however there have been a lot of things done to the engine which make running without b-shafts not make any real difference.

If you haven't lightened any of the rotating assembly and bumped the redline up, you're not going to get a whole lot of gain by just disconnecting the belt.
There are a few pounds to be save by straight up removing the shafts (I've forgotten the exact number but it was more than 10) but again not enough to notice a difference unless you're putting your car on a diet.

JohnKoaWood

Not looking for weight savings, just looking for an easy way to put car back on the road...I picked up a rotating metal on metal whine, parked car shortly after (10 - 20 miles, it started on my way home from work) as it also developed a WP leak around the same time... NEW WP/TB on, test drive and guess what whine still there, and it got a whole lot worse during the 10 mile test ride after new TB and WP were in...

SOOOOO good WP, new TB, I suspect blown bearing on lower balance shaft (good reason to do delete, if no harm is done in the process)
OR blown main Bearing (not my first thought, but could be)...
OR blown oil pump, again, not likely or my first pick but a definite possibility...

IF Balance shaft bearings are good, I will leave them alone, unless I have to do full rebuild, in that case the gloves are off... I am already too deep into the car to even think about parting it, or selling it in current condition... so LS1, 3L Turbo, stock rebuild... who knows where this will end... but I want to drive her... she was my first, and I still love her too much to let her go... I am getting too used to driving the 951 now... I need to come back down to earth...

DDP

John, your best bet is to search here. There are mountains of information at your disposal. Good luck.

fortysixandtwo

In this case, where is seems that you may have a bearing issue with one of the b-shafts, and you really want to drive your car. I say remove the b-shaft belt and enjoy your car for a while. Driving it with a suspect bearing will cause lots-o-damage and isn't worth doing. Especially if it's over something as trivial as the b-shafts. If you decide you don't like the way the engine feels with the b-shafts not hooked up, you'll at least be one step closer to removing them (assuming the whine goes away with the belt disconnected)
Oh, and change your oil and oil filter first.

JohnKoaWood

Well the difference is I do not NEED to drive it, I parked it in November, planned to fix during some off time in December, bought a 951 instead in December, and have spent the past couple months sorting the 951... I am now driving the 951 daily, and feaming for the N/A to be running so I can dump a car or two (Audi TT who's maintenance is a tad more expensive than either the N/A or the 951 so it is first to go).. Like I said I do not NEED the car, but really want it back on the road...


I guess I will take my time and make sure it is done right... and keep the BS for now...but if anything else is wrong it is time to see where there is potential in the N/A motor to be had...

evil 944t

don't do it. (unless you turn a very high RPM and I know nobody on RL is near that rpm limit)

Chris White

I hate balance shaft delete engines.....
in a pinch (like just moving the car around) just remove the belt until you can fix the probblem.

Swagger93

The stock motor is a lot more pleasant to drive with the balance shafts connected. There's more vibration across the rev band without them, particularly at 3500 and above.

Similarly, the idea that the additional vibration from disabled balance shafts causes the engine to vibrate to pieces is the most retarded thing I've ever heard. Maybe if you drive an almost-junkyard-ready 951 around, in which case I can't believe it's working anyhow.

The PO reinstalled the sprockets incorrectly so I'm currently balance shaft belt-less right now. It doesn't hurt.

LS1Porch

Obviously a lot of people here who posted their opinions without reading first...

Anyways, if you think the balance shafts are causing the noise, pull the belt and find out! What's the worst that could happen?

pjburges

Agreed, Take the belt off, its quick and easy, to find out if thats the problem, it wont hurt the engine to run without them on the short term (YMMV)

Chris White

So far I have built 2 engines for engine failures casued by balance shaft delete set ups (delete set up NOT by me - failed oil pump pick ups).

Porsche tried a balance shaft delete program for the Lemans program...had the same problem. So I am glad to be in good retarded company!

If thats the most retarded thing you have ever heard then you must not read all the posts on Rennlist!