I'm building a 355, and was wondering if i should just buy a new OEM harmonic balancer instead of a 300 dollar fluid filled one. I planning on shifting at 6500 to 6600, and putting around 400 to the wheels. What do you guys think?

 

You should at least get a keyed dampener hub.

 

Go with good quality viscous (i.e. stock-type) damper. I am using a Pioneer, and shift at 6400 RPM. I've been doing track days where we hit 6400 RPM about 20 times per lap, and we'll do a hundred laps in a given day. That's 2000 trips to 6000+ RPM each day at the track. My balancer cost me about a hundred bucks.

The engineers at Scat once told me that there were seeing unexplained crank bearing failures on engines with fluid-type dampers. This was, oh, about 2000 or 2001. They hadn't seen the same failures with conventional dampers. By now it might be different. However at the time, I decided to put my extra $200 of savings into converting to ARP main studs and line boring the whole thing. It seemed to do the job.

 

Now that is what I call tried and tested!

 

i got the powerbond SFI one, cheap alternative to the ATI and about 180 dollars cheaper with hub.

 

Heres a Pioneer one from autozone.
http://www.autozone.com/R,APP787727/...ductDetail.htm
Is this the one your running? Or this one?
http://store.summitracing.com/partde...5&autoview=sku

 

93,
I speak from the realm of the gen1 SBC, with Miniram EFI, which is similar, but not the same as the LT1. The Pioneer balancer I used was the smaller 6.75 inch (or is it 6.25 inches?), polished steel balancer with SFI certification. I built a fast-revving road course engine so angular momentum was secondary to getting rid of reciprocating mass.

JEGS 51600 might be the balancer I have. I got mine through Dallas Export Sales and they imported it from Pioneer, out of Australia. http://www.jegs.com/i/JEGS/555/51600/10002/-1

Then again, this might be it: PIO-872021 as seen at Summit. It's been eight years since I ordered it, and honestly I have forgotten the part number. The point is that in my opinion, an SFI approved steel balancer is probably just fine for all occasional-use street/strip engines. The extra fluid coupling & damping is doing what? It's sucking up vibrations that don't seem to be a problem so long as you have a balanced reciprocating assembly. It's also sucking up car money that could be used to actually make it go faster.

JEGS & Summit might have an LT1 equivilant which is slightly different from the SBC one I use: http://store.summitracing.com/partde...5&autoview=sku

However, I'd go over to Dallas Export Sales (www.strokermotor.com) and ask them for their price on part number 872047, which is the SFI approved version for the LT1. They might actually beat JEGS or Summit's price in this case.