The Project Pad

Ok, back on topic now. More about revving to the moon and less about how Chris is a richard.

loxxrider wrote:This has been building up for a long time. While admittedly funny, it (their shenanigans) was definitely done in malevolence, spite, or whatever you want to call it. I guess they know I don't exactly jive with them... I've called them out on a lot of issues in the past and constantly refer people to Marc or Hank when they want to buy parts, but sorry... if your stuff is sub-par, I'm not going to recommend it. I have kept my mouth shut for a long time and so have many others, and for what? We only did it so we wouldn't lose our beloved forum and community. Well, that isn't an issue anymore

Still, I didn't do anything more than move my thread and announce that it would be here so people could continue following and not have to wonder what the heck happened. I tried to bow out graciously, but they kind of ruined that for themselves. I haven't said anything negative in a LONG time because I have been biting my tongue. I still haven't over there; I just made that announcement, that is it.

I kind of figured it out this is what was going on. I had to come over here to confirm my instincts. funny or not the name change was not professional and showed low class

i see the migration of the full thread is taking place....

Aaron, I was wondering why you said what you said about the Fluidamprs a few pages back. I had heard similar things, but was wondering what you had to say about them.

loxxrider wrote:Aaron, I was wondering why you said what you said about the Fluidamprs a few pages back. I had heard similar things, but was wondering what you had to say about them.

Me too, actually.

Looks good Chris.

Glad I found my way over here... now to get another VAG product...

Oh Maaaarc...

where are the pretty pictures?

he took one when I was there yesterday.

Looks exquisite in person, right Jim?....

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haha

This thread is weak.

Ya we need some freakin updates.

dry sump tank mounted. line routing next.

Dang, that is sexy.

85oceanic wrote:Dang, that is sexy.

Agreed, but that's all we get?! Come on, just one more... just one? This build is like crack

So I'm still trying to figure out the biggest major hurdle we've come across at this point, the crank balancer/vibration damper. It would be easy if we could just use a Fluidampr, but I am really not comfortable running one at high RPM. It seems this engine will pretty much have to use an ATI damper if I am to have peace of mind there. That will require a custom adapter, but that is pretty easily doable. The bigger problem is the worry of the damper coming loose due to torsional forces generated by combustion. From these forces, you have in effect, a rotating imbalance as the shaft becomes physically "noodled". The end result of this plus forces from the alternator, head components,dry sump drive, and others is more torque on the balancer/crank interface than stock.

It would be very nice to have a sort of fail-safe for the crank pulley and thus the crank cog from rotating with respect to the crankshaft in the event that the frictional force from the crank bolt is not enough. There are three options which can help in this case. One would be just to pin the whole assembly to the crankshaft. The thing that bothers me about that is that a pin or key shouldn't be used to transmit torque. I'm worried about a pin or key shearing. The second option is to use a key or a number of keys between the crank and cogs, but that has the same problem as option one, though they may be a bit stronger. The third option is to spline the crankshaft and make an entirely new crank cog/ds cog assembly which can mate with the splines. That is the best solution, but would cost a LOT.

Now, I've been worrying about shear a lot in the event that the frictional interface fails altogether, but that is likely not going to happen. If everything is torqued and lock-tite'd properly, then the pins/keys shouldn't have to bare much shear. They'd just be able to help in the event that there was some tendency for the frictional interface to slip. That coupled with the hardened steel cog with relatively large key that I already have on the car should probably be "enough," but when dealing with the kind of $$ involved in this engine, you can probably see why I am inclined to worry a little.

I know a lot of the Chevy guys running superchargers pin their cranks in the manner I described to stop their crank pulleys from spinning on the crank.

Thoughts? I'd love to do some calculations on this, but it is just too much for me at the moment to try and estimate what forces may be present from torsion.

I forgot to add... one last option is to weld the crank cog to the crank... That is getting a bit extreme though. Makes servicing the front crank seal a bitch

I dont remember reading it, but are you running a girdle? That along with machined main caps should help keep the crank from twisting the caps and 'noodling' at high HP/rpm...at least between the end bearings.

Yes, and Yes.

Pinning should do the trick. The pin isn't really taking massive forces. The idea of the pin is that it is a tight fit and hence takes up any tolerance issues. I.e it stops any tiny rotational motion that the taper friction for and bolt might allow. O ER time those tiny slips lead to some looseness and once that happens you are screwed as the balancer can get a bit of a 'run up' at rotating, at which point the shear loads on a pin would be huge. Denying the 'run up' I. The first place means the shear loads are much smaller.

IMHO

Agreed, some early TDI and 16v guys were pinning the crank sprocket b/c the keyway liked to shear off. There was a guy that even had a jig to do the modification with the engine in-car. It was an interference fit hardened steel pin. Probably good to make sure everything is balanced after pinning the pulley.

Brendan

That makes me feel better, thanks! I did see the TDI and 16v guys in my research. It seemed unnecessary for them to do it as it didn't seem like there were really problems if everything was properly torqued. Somewhere on a Chevy forum, they mentioned the balance thing... but then you have to remember that you are replacing steel where steel once was, so it really shouldn't do anything to the balance. Also remember how close to the centerline it is and it really really shouldn't matter. Even so, the balance could be done with it pinned if necessary.

H, when I was talking to Jeff G., he did mention seeing little micro-welds formed at the crank/damper interface from vibration/slips just as you mentioned. That just seems crazy! It does validate your message though. It seems that the solution here is to make sure that everything is true, clean, and pinned when it is all assembled and then we can just hope/pray for the best.

Hope, pray and spend monies is the best we can do

The key (excuse the pun) is absolutely as you say ie ensure the mating tapers are perfect, pin is a good interference fit and is made of hardened steel. It's the tiny tiny movements you need to stop, if you stop those then the big ones won't happen.

The hard part in all this is that you also need to be able to disassemble it from time to time, meaning you can't really use shaft locking compounds.

H

When my rotating assembly was recently balanced I wanted to pin my crank as well but the machinist said he wouldn't do it on a hardened cog because it may crack. If you get your own cog made it shouldn't be a problem though.