Determining proper valve clearance, on a custom build Options

[3liter914-6]

Almost 2 years ago, my brother purchased a 2270 for his 914. I installed it, but really haven't had a chance to run it until this week. On startup, there's a little ticking noise that sounds like a loose valve to me, so I wanted to make sure I have the clearances set correctly. It's been so long since I set them that I don't remember what spec I used, but thinking about it now, I'm not sure what spec to use.

It's a 2270cc engine built by a member of this board that I don't think visits/posts much anymore.

Here are the specs I was able to piece together from old posts here and elsewhere:

2270, 78.4x96, T1 rods - Scat I-beams. Reduced base-circle 163/86B webcam. 9.1:1
1.7L rockers, 911 valve adjusters, with about 60-thou taken off for clearance.
1.8L head with (48x38) valves

So, what spec do I use to adjust the valves? It's a 1.8L head, so do I use that? or...? I guess the question is, what determines what valve clearance you use on a non-stock engine.

Thanks for any information!

[craig downs]

If you have chromoly pushrods you adjust them with 0 lash.

[Twystd1]

Aluminum push rods?

Or CroMo?

If you don't know... You can pull the valve covers and at least see if they are steel or aluminum.

IMHO..
If they are aluminum: Set rockers at 6 thou.

If steel: Set rockers at 1 - 2 thou. And see if they make noise.

Those are typical baseline figures for these Push Rods.

Let the engine warm up and see what ya get.

Typically I set my CroMoly push rods pretty close to ZERO cleareance.
If I don't know who made em. I set em at 2 thou and see how loud they get after a complete warm up and a bit of a drive. If they are clacking. I will set em down to ZERO on a cold engine.

As long as the engine doesn't spit back through the carbs or exhaust. I know I am good. Then verify with a quick compression test.

Thats the problem with unknown steel PRs. You might have to play with em to find out what works best for the engine.

You can also check the rockers HOT and check the clearances. In a perfect world. When an engine is at running temp. There would be ZERO clearance between the rocker arms and the PR.

You also have to get the car up on a jack pretty fast and get the valve covers off to check this. If ya have headers... it's much easier. With HEs.. it's a pain in the ass.

Yet it will get you exactly dead nuts on most of the time.

NOTE: This assumes NON HYDRO LIFTERS..!!!!!

As I don't know squat about hydro lifters in a Type IV engine.

Now lets see what the smart guys say. All I know is.. it works for me.

Clayton

[Aaron Cox]

(IMG:style_emoticons/default/agree.gif) what she ^^ said.

Im with alice.

[3liter914-6]

Thanks for the quick responses guys. Knowing that it came down to the pushrods, I was find a post describing which ones he used (Aircooled.net's HD aluminum). They say to set them at .006, so I've got the feeler gauges, and I'm headed out there. I'll do a sanity check to make sure they're the rods I expect, but I should be good.

Thanks again.