bought an ATI balancer, but found that none of the holes line up with the oem pulleys. anybody had this problem?
It is a BBC balancer with a BBB hub on it. Not only is the pulley bolt pattern for a BBC it stands taller so it will cause alignment issues there also. In my pic you can see 3 different SFI Balancer's, BHJ, ATI and Romac. The end of the hub butt's up against the crank timing gear so you can see how the ATI sits talk then the others. BHJ is really the only true bolt on replacement Balancer. The Romac is smaller ID and will need some grinding on the timing cover to clear. Another problem to watch out for is some of the ATI's fit loose on the crank snout which if used will cause harmonic's and possible bearing problems.
warmed up the ati to go on. length is not a a problem for the dragster. I have to modify things. just can't bolt the stock pulley and blower pulley on. bolt holes are way off. another question for ati.
If you send it back to ATI they can drill it for the Buick pulley set up for a fee of course. They do it all the time for us when we order them.
I haven't been so lucky Jim, the Romac is thicker then a stock or BHJ balancer. The order of the pictures might be mixed up but you can see the one that has the Harmonic balancer installation tool attached to it and I had to stop because not only was hitting the cover but also was up against the girdle spacer.
It should have 3 bolt holes vs the 6 bolt holes that buick uses. Those 3 bolt holes are a chev bolt pattern. That balancer is taller then stock and will change the alignment if using stock pulleys.
Weird -- never had an issue with the Romac either other than the length of bolt being longer. Wonder why you've had a different experience then us Chris?
All I can do is tell you what I have run into and supply pictures to show what needs to be done to run it. I am sure that different covers may have more room then others ie: TA cover and maybe different factory covers might vary. The balancer in the pic below was installed by someone else that not noticed that there was a clearance issue as you can see on assembly. If you do a lot of 1 thing you will see things others don't know to look for. o No:
The snout on the Balancer butt's up against the crank timing gear inside the cover so you can see the big difference between the BHJ and Robmac and you can clearly see why the Romac sits against the timing cover. That big gap means the Romac is that much shorter then a stock or BHJ balancer hence the body of the Romac is also thicker to get the pulley alignment back.
i have a ati on mine.3 bolt holes.if you can find a 350 buick crank pulley it works ok but only for a alt. belt.
back and forth with ati about the 3 holes. told them i'm running a blower, holes don't line up for blower pulley and a blower belt will put a lot of tension on just 3 bolts. plus i will be still have an alt pulley. some things can be modified, some not. ati needs to get their act together.
Not to complicate things more but If you are running a blower the crank and balancer should have a second key way cut in them if they haven't been done already.
Years ago when I put that in my racer,I used the stock pulley,from the back of the balancer I marked the pulley for the 3 Chevy holes,drilled it pulley and no problems with that.I did however have a problem with the timing tip,shaved down some,I don't use it anyway.The other thing,its pressed in,just used an installer and puller.Bruno
I use a Moroso 3 hole BB Chevy pulley and enlarge the center. I complained to ATI years ago in person (they are local). They acted like we were lucky they made one at all for Buick.