7 replies to this topic

[andywilson]

hi all i've stripped down my spare engine and have the balancer shaft in front of me now... what does it do?! i'm guessing GM put it there for a good reason but cant understand why they put it in if it works without it?! what comprimises are there? also, does anyone have any pictures of the balancer shaft delete kit? wouldnt mind having a go at making my own if its possible. cheers, andy

[andywilson]

should have looked harder for the picture

[Mangham54]

They are simply there to reduce the vibrations caused by the crank and general momentum of the other moving parts. They spin at crank speed but in the opposite direction so as to 'balance' out the vibrations. People don't want anything other than silky smooth engines these days, hence for these contra-rotating shafts.

[VIX]

Plenty of stuff here: http://www.google.co...afe=images&tbs=

[Whiteboy]

It also saves about 6 kg. Steve

[Nev]

Andy if you want to make a DIY one yourself its quite easy. The steps are: 1: Get a ladder is off an X20XEV engine (Im only 75% sure about this), so you could pick one up for a £10er of eBay I expect. 2: You need to tap and thread the 2 oil feeds that used to lead to the counter rotating shafts. Insert 2 suitable grub screws (with threadlock) to block these off. 3: You will need to make a baffle out of sheeting. However, this is not 100% vital, as I don't have one in my new engine. In fact, you could argue that its better to not have a baffle as it allows more splash under the pistons. 4: You may need to saw the old pickup pipe and make it bend at a slightly diff angle to avoid the X20XEV ladder which is a different shape to the OEM. You would need to weld/braize this. Also, it's worth considering putting a baffle or 2 in the sump if you intend to track the car with sustained cornering. I know a chap who will weld these in for approx £50 if you want. IMO it is worth binning the counter-rotating shafts. Doing so won't compromise your engine longevity, though you may get slightly more vibration. If you do this with other changes, like a lightened flywheel + short pully mod, you will end up with an engine that wants to rev a good deal more snapily. Give the whole engine more of a racey feel if thats what youre after. Pip pip.

Edited by Nev, 02 July 2011 - 09:06 PM.

[andywilson]

many thanks chaps helpful as ever! i'll keep my eyes peeled for a X20XEV ladder, should be a fair bit cheaper than the courtenay offering. the baffle wont be a problem, will do a cad drawing and use the laser cutter at work. as for putting a couple of baffles in the sump... im sure ive seen pictures somewhere... but i cant find them. does anyone have any pics of roughly where they should go? and i'll get them tacked in today. regards, andy

[Nev]

Andy, I dont know anyone who has baffled an OEM Z20LET sump, but there is a chap on the MIG website who posted some pics of his baffling on a C20LET. His name is Dewisport and he has a huge thread on that website. He's the guy who offeres a baffling service for £50. Please double check its an X20XEV ladder that you need, if it's not then it some other old Vaux engine parts.

Edited by Nev, 03 July 2011 - 11:46 AM.