455 Crankshaft O.D./Harmonic Balancer Question

Return it and get the correct slip fit balancer from TA Performance.

From the TA website:

"Stock & Stock Replacement Buick Balancers are not pressed on, they should slide on by hand. Forcing the balancer on could cause the balancer to crack at the keyway."

 

I know but once he heats it there is no return likely. I would get JW on this thread since he has installed hundreds of these.

 

Ok so no heat ,what about turning the the bore out to the size of the crank about .5 of a mm then recut the keyway

 

Wait until JW responds. He is a professional Buick engine builder and he owns this website.

 

ok

 

I just checked 8 clean 455 crankshafts here at work and they all measured 1.438. I measured with a mic first and double checked with a caliper. Hopefully this is of some help.

Larry

 

A while back I was building a customers Pontiac Stroker engine and had the same issue with a BHJ damper. BHJ offered to hone it for a factory slip fit but we opted to have our machine shop hone it because of the aftermarket offshore forged crankshaft that came in the kit. I felt it was best to fit it to that exact crankshaft. You could have a trusted shop in your area do the same. As others have already said , .... JW would know what's best in this situation.

Larry

 

ATI External balance BBB dampers are the hardest to work with, they don't clear the timing tab on the cover. You have to grind the snot out of the tab to shorten it. ATI states that your suppose to run the damper .745 farther out to clear the timing cover. Of course, then none of your belts will line up. The better solution for an ATI damper is to shorten the hub and clearance the timing tab. The external balance weight is the issue here, and for this reason, I have not used an ATI damper on a external balanced Buick for about 20 years.. I do use them on internal balance race motors, they are a very good damper.

In that application, we shorten the hub to correctly locate the face of the damper.

All ATI damper hubs must be honed for fit. I have brand new one here, and it came out of the box at 1.434. Crower cranks are typically 1.439, Stock ones will vary a touch, I have seen a lot of them around 1.4380 to 1.4385. I happen to have a never run NOS factory 455 crank in the shop now that measures 1.4380.

ATI specs the press fit to be .0007 to .0009. (.0177 to .0228mm for our friends on the metric system)

All press fit aftermarket BBB dampers must be installed with the proper installation tool. I have a
Snap on (Blue Point) one that is similar to this..

https://www.amazon.com/OEMTOOLS-27144-Harmonic-Balancer-Installer/dp/B0006307YU
/ref=pd_lpo_vtph_263_lp_img_2?_encoding=UTF8&psc=1&refRID=9KY8XFK8K09GP27WVYWJ

Whatever installation tool you buy, make sure it has a 3/4-16 adapter, that is the size of the crank threads.

Do not, under any circumstances, attempt to heat or pound the damper in place, you will more than likely destroy it.

My advice to you... return it and get either a new stock replacement, or if your looking for an SFI approved one, buy a Romac or BHJ. TA does take orders via email for those of you overseas, or find it otherwise hard to call them during normal business hours.

The stock replacement damper will just slide on, all aftermarket SFI dampers are press fit, and the same fitting instructions apply. The BHJ and Romac dampers are typically about a thou press fit, right out of the box, we just dust them out a touch on the hone, and lube everything up when installing them. ATI dampers have always been really small, not unusual to have to take .003 to .005 out of them.

Good luck.

JW

PS... I was thinking about this walking in from the shop tonight, and I recall the other reason I don't use them on my street builds.. that damper only has a 3 bolt BBC bolt pattern on it, for the crank pulley..

 

Crank hog....

If you come to work one morning and they are missing... ... I don't know anything about it....

JW

 

I remember you had an interest in those when you stopped in a while back, .... so when I thin the herd you will be the first I call.

Larry

 

Thanks Larry, I am always looking for a few good cranks... I had so many at one time I had to build a custom rack to hang them all... I had dozens of them, but that was many moons (and engine builds) ago.

 

I hone all SFI balancers a few thou to create a factory type slip fit.

 

Thanks Jim for the invaluable info ,i got the Hb honed and it fits like a glove

 

A little off topic but is your dad's name James?

That would be SO FRICKEN COOL!

 

haha no but mum wanted to name me james, but the old boy thought id get into to much trouble

 

I know this is an old thread, but my 20+ year old ATI damper is a slip fit, like a stock piece. But it does have all the other fitment problems...wont clear the timing tab on Front Cover and it sits too far out for pulleys to line up. I also can use a stock length 3/4" bolt.