Since I got the motor back in and running it is much quieter but I still have a lot more noise than most type IV's.

It sounds like it is all valve train noise. I did not upgrade to 1.7 rockers and swivel feet but I did install new Porsche Genuine adjusters. I've adjusted them to .006" cold.

Someone at GNR told me I could tighten that up to .003" and that might eliminate a lot of the noise.

This doesn't sound like the best idea to me and I only remember seeing the normal .006 mention online so I figured I'd see if anyone actually does this?

The car has a WebCam w/ Solid lifters and chromoly pushrods (non-HD) and solid spacers on the rockers. 2.0L 3 stud heads.

Thanks guys,

Andy

Well, lots of specifics here, but as Chromoly pushrods have a different expansion rate from the original Al ones, most people run them at 0.00 clearance COLD.

DO some searches as I can't spend more time online now.

Good luck!

Thanks Eric, I like to toss softballs out once in a while

Why 0.000 clearance? how about the expansion of the valve- like on the exhaust side?
please educate me / us.

thanks

Correct me if I'm wrong, but I believe this has to do with the expansion rates of aluminum vs. steel. As the motor heats up, the entire engine gets a little bit wider alogn with all the moving parts inside the engine. AL pushrods expand greater than the rest of engine, so in theory, .006 cold will be .001 when the motor is hot. Chromoly on the other hand expands at the same rate as the cast iron cylinders, so zero cold lash results in about .001-.002 hot.

Then again, I'm sick as a dog, so this this might not make any sense to normal people..

valve is much shorter than push rod... less expansion

If you would like to know for sure what your specific engine needs, you can adjust them hot.

Get the motor nice and hot, adjust to 0.00 when hot.
Let it cool and see what the measurement is when cold, then you will know forever what YOUR motor with YOUR cylinders and YOUR push rods needs for adjustment.

The OEM adjustment was for the cast iron cylinders, the OEM camshaft, the OEM push rods, and the OEM lifters and valve.
You replaced some of this with untested metal...

The OEM spec of 006/008 when cold ends up at 0.00 when hot once everything heats up.

You never want your valves adjusted to tight or they wont close all the way, you can burn a valve, the car will run lean, and it will never tune properly.

Doing it hot does suck, but do it once (with gloves) and you will then know what a safe adjustment is for your car with all the differing metals you have to work with.

rich

That makes a lot of sense to me Ethan. In fact, I never knew that was why the spec for stock valve lash was so large, so thanks for explaining.

BTW, you DO know this is 914World, right? There are no "normal" people here.

I would adjust to .001" intake and .003" exhaust

The reason for the factory delta of .002" for the exhaust, is the exhaust valve does get hotter and does expand more than the intake valve. Chromoly push rods will not change the expansion amount of the exhaust valve when compared to the intake valve.

I went 150,000 miles and 7 years without needing to make an alteration in valve clearances when set to .000 Intake and exhaust on this engine.
http://www.aircooledtechnology.com/index.p...ileage-teardown

I routinely checked the clearances, but they were fine every time after street and track time. Don't be afraid to run tighter clearances with chromoly pushrods, running them loose just costs lift, duration and makes the engine sound like a small diesel. With these pushrods you always know when the valves need adjusting, because the engine pops and cracks out the intake (tight intake valves) or the exhaust(tight exhaust values) when it is stone cold, but goes away when warmed up.

With chromoly pushrods valves tighten when the engine is cold, with aluminum they tighten when the engine is hot. I'd rather have tight valves on a cold engine with cooler combustion temperatures.

On this topic you can ask the experts and get 15 different answers.

No, it was because the OEM exhaust valves were sodium filled and needed the extra expansion.
Run 0.00 on this engine as Jake recommends so you don't smash the heck out of the valves tips.

Excessive lash kills the valve train.

How could you tell the OP does not have OEM 2.0 valves from his post?

But good to know what reasons the factory had for their specs.

Even with sodium filled valves I have used .000 with chromoly pushrods. Pushrod material has proven to trump all factors in my experience when it comes to the optimum valve lash.

They are SS valves, I'll reset to 0 lash cold tonight and report back.

Thanks again for the advice, the thing sounds awful right now

I think you'll be pleasantly surprised with the difference a few thousandths of an inch can make.

Drum roll.....

That's what I tell my .........

Hey all, thanks for the education -

That must be why she keeps calling.....

Wow, it's so much quieter! Sounds like 1 or 2 might have a little bit of slack still, I'll do another adjustment this weekend.

Thanks guys

good news.
I was not kidding about adjusting them hot, though it may suck the one time you do it.
Many racers will do this track side.

Your adjustments are all about the differing metals of your motor. The case and if it is really flat, the heads and how the are seated, the torque of the head...
the list can go on to account for many difference between your engine and mine.

Its not a one size fits all answer.

To get it optimum and performing at its best, you need to understand where the settings are when hot.

Just saying.

Rich

On the way to work today a lot of the noise came back. I'm going to do a hot adjustment tonight and see from there.

It's simple enough, don't even need to jack up the car, how hard could it be (famous last words).

If that fails I may replace the adjusters, or at least pull them to see if there is any noticeable damage. Thinking maybe they pitted from the hammering action they were going through, now that I tightened them, it might have worn them smooth which accounts for the change in noise from last night to today.

ChroMoly pushrods will increase in gap when getting hot. So they will be quieter at first startup, then get slightly louder. If you adjust them hot, make sure they still have clearance when cold.

+1 ..... that would be the way I would do it ........... after reading other people's experience on chromoly push rods ..... I would do .001" or maybe even half that clearance when cold ..... and run the swivel feet adjusters ........

However my engine has alloy push rods, solid SS valves and swivel feet ..... so I will be experimenting with bigger gaps that close upon warm up .....

Absolutely should be running 911 adjusters and a solid spacer kit. If you don't have the solid spacers a lot of the noise you are hearing is lateral side play. This costs duration, and makes for a louder valve train, too.

Whatever happened to the overhead valve head those guys in Europe (maybe) were working on many years ago....

I forgot most of the details but I was really hoping someone would get it done, just to provide a really slick solution to this.

http://www.914world.com/bbs2/index.php?sho...;p=1563538&

http://www.thesamba.com/vw/forum/viewtopic.php?t=380497

After doing the hot adjustment, the car is very quiet, but is harder to start cold with more backfire (valves not closing entirely).

I'm going to check them out cold and see what the clearance is like.

I already have solid spacers installed but I have the 2.0 rockers with point adjusters. I have a feeling this is causing a good amount of noise when I set the clearance to .000 when cold (small point hitting the valve instead of a nice wide foot).

It's good to hear the engine run so quietly but I do not want to grenade the thing in search of a quieter running engine. I guess I'll have to pull the engine and redo valve train geometry with 1.7L rockers and 911 swivel feet. I can take care of leaks while it's out.

Once I finish screwing around with the girl's nightmarish Volvo I'll be able to get something done on this.

It appears that the genuine porsche 911 swivel feet are the best parts available ($23 each, ouch) and only acceptable swivel feet for my application.

Just want to verify this is still the case, no one has started making a good quality replacement.

Thanks Rich,
I can hardly wait to have hot oil running up my nose and arm pit. Of course ymmv.