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Valve Spring Tension?

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Old Oct 5, 2004 | 07:40 PM
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Default Valve Spring Tension?

Anyone know what the OEM spring tension is for the early 2V motors? 78-82 or so?

Spring sets are, oh, 60 bucks each *valve* and I'm not that nuts.

Any info anywhere around this subject?

My mechanic is looking at crower, and they have a nice set in the same *dimensions* but we need the rating of the tension.

Thanks
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Old Oct 5, 2004 | 08:06 PM
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Anyone? I was suspecting this may be difficult.
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Old Oct 5, 2004 | 08:09 PM
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Are you going to put in a valve spring oil spray cooling system too?

"Keeping valvesprings cool is a doorway to good engine production. Many good oil-spray valve covers are available to help in spring cooling. A key to making these systems work to their fullest potential lies in the oil source. A separate oil line directly from the oil cooler is recommended. Taking the oil out of the block before it has gone through the oil-cooling unit is placing hot oil into a hot environment. Keeping valvesprings cool is a means of maintaining seat pressures. This translates into consistent power from the green to the checkered flag." (www.circletrack.com)
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Old Oct 5, 2004 | 08:30 PM
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Very nice.

You done with the sunroof yet?

How much for the cool light thing?

What other stuff you got?
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Old Oct 5, 2004 | 10:01 PM
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Default Since you asked...

Brendan,

Note, according to the WSM, there was a change in springs with M28-11/12. Unfortunately, the WSM only shows checking the length of the installed springs, not the actual tension of the dual springs. You'll have to measure some new springs to get the spring rate.
...

On to the off topic section... I have been busy with work and such, so I haven't had time to work on anything cool.

The sunroof is conceptually ready. I've been driving around with the prototype since I installed it and I love it. I just need to make a form and get hold of a laser cutter shop to go ahead. (your cost ~$250)

RE. the projectors: I've decided to center the low beam in the old headlight opening, and put the low beam in place of the US parking light (fits nicely). There is too much cutoff on the sides currently. (lights from {here} ~$230; brackets, wire harness from me ~$100)
...

I've been thinking about a couple of things - but realistically only for myself...

What I could put together right now:
Drivetrain:
~Open airbox lid
~Vacuum cap set
~Cold start delete kit
~32V cam gear upgrade
~Rrear auto trans cooler
Body:
~Screen grill
~Acrylic sunroof
~Rear light brain delete
~Projector fixed headlights
~Retracting front license plate

What I've thought about:
Drivetrain:
~Engine stud kit
~Poly engine mounts
~Phenolic intake spacers
~Crankcase vacuum pump
~Automatic timing belt tensioner
~Variable geometry exhaust system
~Plain, non-locking replacement gas cap
Body:
~LED rear taillights
~Bumperette delete panel
~Underbody smoothing panels
~Pop-up air brake/hatch air brush
~Underfloor mounted windshield washer tank
~Antenna removal replacement brace, body plug
~Race heater/defrost system (backseat mounted?)
~RS interior panels (bare aluminum, leather covered)
~Alcantera/ultrasuede pod cover to match suede Momo steering wheel

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Old Oct 6, 2004 | 12:07 AM
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Right. Since there is no real answers that I can see on the springs, I guess this is my thread to do what I will with...

-Sunroof - I'm in.

- Headlights, etc - get working on that. I need that setup for my 78. Chrome rings, new buckets, brackets are rusted, etc.- I like your ideas.

32V cam gear - I need this for my mouse motor on the 78. Its an 81 long block with 78 cams (if I find they are usable). So I also have two later style cam gears. What else do you need from me? Parts? I need that to put my engineb ack together, so can you put it together in the next few weeks?
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Old Oct 6, 2004 | 12:46 AM
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I hope to get some time to work on the sunroof, and the lights, soon. If you really want something NOW, then PM me, and I'll give you my paypal address, and then maybe I can rationalize it to 'Frau Director'...
...

For the variable cam setup, I've got a set of used 32V timing gear hubs, already machined, or I have a set of new hubs that I could have machined. I would have only to make another pointer for you, to set them up.

You'll need HTD crank and oil pump gears, as well as the 32V cam gears you have.
...

I'm interested in how the 78 cams will advance/retard, since I'm sitting on a set of 79s.

One (nice?) thing about the 78-79 cams is that they use woodruff keys instead of the later parallel keys to mount the cam gears, and the distributor gear. I'm pretty sure that the key is the same size as Mercedes keys, for which there are readily available fixed offset keys:


click pic for larger
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Old Oct 6, 2004 | 01:01 PM
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INteresting. Can you send your paypal address to:
brendancampion@***.net

YOu need my 32V cam gears because you want mine for cores, or what?

What would that offset woodruff key do for the adjustable cam gear openings on the 32V set?
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Old Oct 6, 2004 | 01:57 PM
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I don't need to have any of the gears from you. No modification is needed for the gears. If you have hubs to send, then that would save you some $$.

All you need from me is the machined timing gear hubs, pointer, and harware (lower):


click pic for post: 32V adjustable cam sprockets/16V installed


Sorry, I just muddied the waters by mentioning the fixed advance keys, but I wanted to put it out there.

The offset keys would do nothing for the 32V gears, but they would work with the original non-adjustable gears to give a fixed advance. Say if all a person wanted was to bring the right gear closer to it's mark.
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