Loose heads?

Who is the best person to rebuild your engine? You...
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Max Welton
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Joined: Mon Jun 03, 2002 12:01 am

Post by Max Welton »

wine country ghia wrote:Excellent tuturial Max thanks! yeah I just ordered the same tool I like the metal tape idea I was just going to paint it this may sound like a stupid question how did you calculate 5/8 turns?

Thanks,
-Eric
I just eyeballed it. ;-) It's easy to spot whole quarter-turns and that looks to be just about half way between the 1/2 and 3/4 points.

One could also measure the angle on a print-out of the digital image using a protractor.
Guest

Post by Guest »

Thanks Max my tools are on there way I'll report the relults next weekend providing all goes well.

Cheers,
-Eric
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wine country ghia
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Joined: Mon Jul 29, 2002 12:01 am

Post by wine country ghia »

Update:

Ok removed heads pistons and cylinders pistons look pretty good no cracked rings ect a little bit of carbon on the tops but not too bad.
waiting on deck height tool and head cc kit to get here so i can figure out what spacers I'll need also I noticed there seems to be allot of side to side play on my connecting rods is that bad?

-Eric
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Marc
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Post by Marc »

Rod sideplay spec is .004-.016" with a wear limit of .028". Right around .012" makes me happy.
I've known people who hung 1600 rods on a 1200 crank, which creates an obscene amount of sideplay - but their engines still ran. Not good for oil pressure....
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wine country ghia
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Post by wine country ghia »

Update:

Ok the measurments are in they are the following:

Heads measured using head ccing syringe kit:

Port 1 = 51cc
Port 2 = 51cc
Port 3 = 50cc
Port 4 = 51cc

Avg = 51cc

Deck Height measurements with calibrated scew/deck height tool no shims:

Cylinder 1: aprox .030
Cylinder 2: aprox .030
Cylinder 3: aprox .027.5
Cylinder 4: aprox .030

Avg Deck: .030

I used .031 barrel shims with Permitex red hightemp silicone

Remeasured deck:

Cylinder 1: aprox .070
Cylinder 2: aprox .070
Cylinder 3: aprox .067.5
Cylinder 4: aprox .070

Final compression ratio: 7.5:1

So I should be dialed right in there thanks guys! Still need to finish the assembly but so far so good!. Oh also I reported the case model as the wrong one the case number says AS41 not AS21. It has two oil relief plugs.



Final deck avg: .070

Barrel size: 85.5mm

Stroke 69mm

Cam: stock

-Eric
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wine country ghia
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Post by wine country ghia »

Ok here is the results of the test drive:

Perfectly awsome runs quiet and smooth almost scary smooth. Oil temp is hovering a hair above 180F with ambient temps around 58F. I am getting a metalic tapping sound under acceleration I think the valves need to be adjusted I hope. I ordered an oil temp sender that goes in the front oil releif plug sport I think the readings will be more accurate right now I'm taking temps from the 'T" sender which I don't trust too much. Oh what is the best way to ensure the rings seat well is there any break in restrictions?

My engine combo:

1600cc SP
85.5mm
PICT30/31 carb 127.5 main jet
69mm crank
stock cam
VW MEX dual header echaust system
compression 7.6:1

-Eric
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Max Welton
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Post by Max Welton »

Good job Eric! Sounds like you are just about there.

That sound when accelerating could be a number of things. I've had small exhaust leaks that sounded remarkably metalic and would only show up under load.

On the valve lash, I would stay on the loose side for a couple hundred miles. Sometimes the cylinders/heads/valves settle in a bit and you don't wan't to run out of lash. You might take a look at the rocker assemblies just to make sure all the washers and clips are still in place.

There seem to be a number of ideas on how to get the rings to seat properly. I personally don't do anything special. I do perform periodic leak-down tests to verify that they are seating, however. My new engine had readings in the 50% range on the bench. Within 100 miles 3 cylinders were down to 5% (#2 took a little longer for some reason).
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Post by Guest »

Hey Max,

Yeah I adjusted the valves before putting the motor in. I took it for a short test drive and parked it for the night. Checked the vales this morning one valve RF was really tight one valve RR was tight and one valve LF was tight readjusted and everything seems quiet now I'll monitor things for a bit to see how it goes well thanks for your help and Marc too yeah it running really good lots more power though I think I need to run 89 I'm getting a little pinging as Marc said 7.4 is about the max for 87 right?

Cheers,
-Eric
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