L-Series Z Engine Dampener

[Ron Earp]

The new race motor is basically done except for front dress and a few things like that. My old "race" engine had a euro dampener on it, but it was broken and is no longer usable.

What do you Z guys run? Should I find another euro unit (they seem to be NLA)? Or just use the stock piece. The stock piece with two pulley groves is quite heavy, but I wonder if it might be better with the long Z crank and quell some vibrational harmonics?

Thanks,
Ron

[pballance]

FWIW, mine is OEM and the engine is rumoured to be "Rebello"

I seem to remember that I saw one(euro) on ebay recently, maybe even over the weekend.

Time for Katman to weigh in.

[Ron Earp]

Jeffery Rousell found these:

http://www.thezstore.com/page/TZS/CTGY/PEM06

Ron

[kthomas]

Our D.L.Potter motors ran a big ole honkin' stock 3 groove harmonic balancer from a 280ZX as I recall. On the Sunbelt engines we ran the single groove "Euro" from Nismo because, well, I got a good deal on one once and we were developing engines so fast I wasn't worried about getting 30 races out of a crank like we used to. Personally I'd run a good condition stock junkyard piece.

Are these "free" now? Can you run an ATI Superdamper or something like that? The problem I have with any aftermarket piece like that is I'm not sure there's any real testing being done for our application. I know from our tests a good stock one works to 7400 rpm all day long. Not sure if ATI or anybody else actually ever instrumented an ITS L24/26/28 to see if their part works or not. YMMV.

[Ron Earp]

Well, they are "free", but they aren't "free" as you can see from the prices. Not bad actually though. Your advice is well taken, sounds like the stocker will work just fine.

The old motor I had did have a euro dampener but as described on my engine thread it failed. After I looked around on the net it looks like these things fail frequently. However, that one on the page from Professional Products would probably be fine. They have made race dampeners for many years and have a good reputation.

I've got a few stockers, and they are definitely free, so that might be best.

R

[x-ring]

So what's the deal with the special bolt? $40 for a bolt?

They used one of these (the $90 one, not the SFI one) when they rebuilt my motor a few weeks ago. Not sure if they used the special bolt or not.

[Ron Earp]

I don't know, I do have the "special bolt" though. It looks to be an ARP-type bolt with a huge thick washer under it to spread the load. I've not reassembled my motor yet so I don't know what we'll use, but I think we'll use a stock dampener and stock bolt.

R

[Parrish57]

I was using a stock damper the last time we ran Lowes. During the Enduro the 35 year old rubber insulator gave up the ghost. The pulley left taking the belt with it. The surprising thing was that it didn't hit ANYTHING on it's way out! The first indication was the water temp going China Syndrome. Bryan pulled over and tried not to get run over. We rebuilt the motor as a precaution. Over all it was not a big deal for us but I'd hate to have been the guy in the SRF that was right on his bumper!

Obviously I now use the Euro damper.

[Ron Earp]

I went ahead and bought the euro dampener. Figure I'll run the new one on my new motor, put the old one on the spare motor. Can't hurt. The old Euro dampener I had was probably from when the car was built in 1991, so indeed it was old. It still worked though and I raced that way at CMP, that is, wobbly pulley/belt, but I didn't know it when I raced down there. Had I known I'd have fixed it.

R

[Ron Earp]

I've a question on the keys for the dampener.

The dampener fits on the crank super tight. So, you essentially only have one chance to line up the key with the notch in the dampener. If you are off, you will squash a key, which I have already done. Fortunately, the fellow who owned the car before me must have squashed a few since I found a bag of five in the spares kit (BTW, the others were easy, like the one for the dizzy drive gear).

How do you fellows manage getting these on correctly with the front and last one?

I know the key fits in the dampener, just barely, by trial fitting off the crank. But there is no room for error. I chamfered the keyway on the dampener too.

Fords don't have this crazyness, they have a notched crank and a machined key in the dampener, the entire length, so it is a no brainer to get it on correctly.

Ron

[[email protected]]

I put the key in, and put the front a little lower than the back, and I mean a little. Then I line it up and slide it on enough to engage it. I have an installation tool I made out of a section of Acme thread rod, an Acme threaded nut. I got a bolt the same thread as the damper bolt and cut the head off. I drilled both the rod and the headless bolt for a pin and then put them together using a pin. I then welded the rod and the headless bolt together. I use a section of roll bar tubing with a welded on flat stock to push the damper on as I tighten the acme threaded nut. Works like a charm.

Mike

[[email protected]]

Something I did putting together small block chevy's years ago, the timing gear on the crank is a very tight fit. Someone told me to put a pan of water on the stove with a little oil in it. Probably vegie to keep your wife from killing you. Put the damper in and bring it to a boil. Pull it out and slide it on the crank. Use really good oven mits to keep from burning yourself.

212 degrees F shouldn't hurt the damper as it lives at that temp under use. Best to let it drain a minute or so as the boiling water will soak through the mits and burn the stuff out of you. I haven't tried this, but I see no reason that it wouldn't work.

Mike

[Ron Earp]

Hey Mike,

that is a good idea! I was thinking about heating it but my brain was locked on a torch, which I didn't want to use because I might get it too hot or burn the middle section that couples the two sides. The water should work, I will try it tonight. If that will work and it'll slide on easily then I won't need the threaded rod trick.

Thanks for the ideas on that, much appreciated. I'll let you know how it turns out.

Did the plate arrive yet? It was sent Thursday or Friday, can't remember, but it isn't far down there.

Best,
Ron

[[email protected]]

Yes the plate arrived Monday. Thanks! Hope the engine makes almost as much power as mine!!!!! I'll try to be out for the October CCPS or Saturday SARRC. Way too many balls in the air recently!

Mike

[Ron Earp]

Nice! :P

Your boiling water trick worked like a champ and I was able to make an "installer" to help things out too. Went on with no problem, then I degreed it with a borrowed wheel and made new marks on the pulley. This should work out okay.

I'd say this is a decent build motor but it isn't a Sam Neeve motor or anything like that. Port work is extremely conversative, header is not optimal, but it does have all new hardware - pistons, valves, springs, and some good rings and good setup with the bearings and machine work. A friend of ours did the bottom end assembly and he does a nice job.

So I hope that even if it doesn't make a ton of power it'll do the important thing - keep me racing without having to work on motors!!!!!!!!!!! I just need seat time!!

I'll get it on a chassis dyno and post results in a couple of weeks. I do want to tune it before doing much else with the car.

R