Does Size really Matter?

[Paul69camaro]

Now that I got your attention, I'm trying to debate whether to buy the 6.325 inch ATI damper or the 7.074" version. Is there any advantages or disadvantages of either? Thanks in Advance for ya's help.



Paul

Oh yeah one other question, on a turbo charged 383 that's going to be used for roadracing, would ya recommend and electric or manual waterpump?

[chicane67]

1. The larger diameter is better suited for sustained high rpms.

2. The smaller would be better for a drag set-up where the burst rpm isnt run for very long.

3. A manual pump would be the correct decision.

[Rick Dorion]

I have the larger ATI as Tom suggested.

I also have a Stewart manual pump - a nice unit.

[Paul69camaro]

Thanks for the help, It looks like I'll be buying the 7" damper. I have also been looking at the stewart pumps but not sure which one yet.

[zbugger]

Heh..... I'm sorry, I just can't help it. I've never seen a manual water pump before. I do know of mechanical one's though. And honestly, that would probably be more reliable for your application.

[OHCbird]

I've run a Davies electric pump for a few years now without any down time; It was used mainly due to space considerations. If you're going to have lots of piping, etc up front- then a mechanical would probably be the best way to go. Stewart, Edelbrock, and Moroso make some good pumps.

[Lowend]

I personally like to run the lightest and smallest diameter balance I can. A low inertial mass on the dampner (and the flywheel) makes it much easier for an engine to change speeds quickly.
Bigger is not better...

[vintageracer]

I run a Stewart pump setup on my Vintage Road Race 66 Shelby GT 350. For road racing this would be the only way to go!

As far as the balancer, that will depend upon the clutch/flyweel type that you intend to run. Triple disc Tilton or Fidanza aluminum flywheel/clutch setup, the balancer weight and size needs to be sized/sourced based upon the complete engine/turbo/FI package which you state above that you do not have at this time. Spend a little time deciding what the final package will be so you do not buy "any" parts more than once!

Whatever you choose, make sure it is NOT one of the "rattler" type of balancers. They may be great for drag cars however they are not for road race cars. Just ask any Cup engine builder.

[Paul69camaro]

Hey Guys thanks for the info, it looks like I'm going to go with the stewart stage four "mechanical" pump, and some spacers to make it work as a long style pump (the stage four only comes in short style) , I'll have to figure out how to mount the accessories though. I was also unaware that the harmonic balancer needs to be spec. with the flywheel and clutch, I'm going to have to look into that. Thanks again for all the input.

Paul