quote:Originally posted by George P:quote:
Originally posted by 1Rocketship:
Does this mean the HEAVY Boss harmonic damper is a better choice for a high revvving (7,000rpm) Cleveland than the ATI damper?!...Mark
No, the heavy ATI damper is the damper with the best feedback amongst grass roots racers. They claim it prevents the production block's bulk heads from cracking when raced with the oem crank at 8000+ rpm. It the only damper I've ever heard people claim to do this, and I've heard it from a hand full of people.
That right there is a great feed back. I'd go with that.
My only comment on it vs. the old Boss balancer is, there is an entire generation that doesn't know it ever existed.
Even my engine "builder" shrugs his shoulders and says the 4v balancer is ok.
It probably is ancient technology now by today's standards BUT if you look at all of the balancers that came from the factory on the FORD performance engines, they are all HUGE and heavy.
I think that my 427 balancer weighs 15 pounds then there is a two sheave cast iron pulley that gets mounted to it as an assembly. Close to 20 pounds total.
The Boss 302, 289 HP and Boss 351 are all in the same catagory weight wise.
I had built a stroker 427, built with a 428 crank, 427 block, 428cj balancer, 427 flywheel precision balanced. The flywheel was wrong and they took weight off of it to balance the assembly.
The 427 as an assembly is neutral balanced all the way through. The 428 is neutral balanced only to the thrust bearing bulkhead, then Detroit balanced to the flywheel.
Because it was a 428 crank, not a 427 crank, it needed to be balanced as a 428.
I supplied them with a 427 flywheel. Neutral balanced. That was wrong.
The engine balancer technician said that was ok and took weight off of the flywheel to Detroit balance it.
There was something not right with the engine as soon as it was started for the first time. All the bolts on the bottom end loosened up within about 20 miles and 20 minutes initial running time.
The engine was out of balance. It had to be completely taken apart and everything redone. It was lucky that the main thrust bearing bulkhead of the block didn't break?
427 Ford blocks will crack right through the main thrust bearing bulkhead when not balanced right. Worse than the Cleveland block. The crack is so bad it will saw tooth the main thrust bearing bulkhead, not just hairline it like the Cleveland does.
The flywheel should have had weight added to it. Mallory metal. You can't take weight off of it. There isn't sufficient mass left to dampen the vibrations.
On a Ford you NEVER touch the balancer or flywheel. You add Mallory metal to the crank if you HAVE TO.
$10,000 mistake by the engine balancer. COST ME $10.000, not him. He just said, "sorry, I don't know what happened here".
Tuition is expensive these days I guess?
The only mass I could add to the engine at that point was not Mallory metal, it was mas Tequila por favor. WHAT A FREAKIN' DISASTER!
This is what happens when "your majority of experience is in balancing Chevys!", and unfortunately that is the vast majority.
If you say I don't know WTF I'm talking about, I'll let you go through the debris and make your own determination.
I say, do not listen to those guys. They don't know what they are doing. Their mistake is just going to cost YOU, not them. This ain't no 9th grade auto shop class. It gets complicated really fast. Too complicated for some. A lot of them never went past 9th grade anyway.
Just for the sake of discussion, not that it really matters at all now, but I'd be interested in what the reciprocating assemblies were on all of those "cracked" Cleveland blocks. Anyone want to cover my bet that they were all internally balanced and weight was taken off of the balancer and flywheel?
You want the biggest ugliest mass you can get on these things. Ugly is beautiful.
