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> everyone knows, I NEED hElP THANK YOU ALL!
worn
post Aug 16 2013, 09:22 AM
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You may remember me from posts like the squid that ate my transmission. I built an engine and have pretty much solved various problems like leaks and oil pressure and oil temp. It is a 2056 with a 73 web cam + 2.5°.

I had to do some work on the heads. I was shooting for about a little over 8:1 compression, and while I have some uncertainty of deck height I am certain of the head chamber volume all matched to 69 cc ( I would say milliliters). According to CB Performance that would give me a maximum of 8.4 compression.

That is the set up here is the problem. On load I hear a ticking sound, with maybe a tinkling high tone. There are several alternative sources of rattling, but it is coming from the engine bay. The gas here is generally 91 octane. I have enriched the MPS to deliver A/F to around 11:1 at load with part throttle and that has not cured the problem. After break in the car turned more difficultly with the starter so I wonder if the cam may be producing better dynamic compression. The heads overheat if I push air down the road at 70 - they generally don't at 50. Timing is stock.

Question 1. Is this knock/ping/pink(UK)?

Question 2. What are my best options and how quickly must they be instituted. The car is grounded for now.

3 - Thanks!
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r_towle
post Aug 16 2013, 04:39 PM
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What distributor?
What fuel source? What carbs? What is the setup on the carbs?
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worn
post Aug 19 2013, 09:47 AM
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QUOTE(r_towle @ Aug 16 2013, 02:39 PM) *

What distributor?
What fuel source? What carbs? What is the setup on the carbs?


Thanks to everyone that chipped in. I love my 914 but was ready to stop driving it indefinitely. But we thought we would back off the timing. I have an adjustable timing light -sometimes it even works. Odd. The mark at 27 degrees BDC shows up at idle, and when you rev the car it doesn't change - it sort of looks like it moves but only a degree or two.

So I swapped in the distributor from the 1.7 with a pertronix trigger. Ping is gone. Wrong dizzy for the car, but the ping is not intrinsic to acceleration any more.

There ought to be a big thanks banner that you can add from the cute little icons, but in the absence of such i shout: THANKS!!!

(IMG:style_emoticons/default/pray.gif) (IMG:style_emoticons/default/laugh.gif) (IMG:style_emoticons/default/aktion035.gif) (IMG:style_emoticons/default/cheer.gif) (IMG:style_emoticons/default/piratenanner.gif)

Now to rebuild a dizzy or find a better one.
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