MPS rebuild, mission accomplished |
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MPS rebuild, mission accomplished |
emerygt350 |
Oct 27 2021, 12:07 PM
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#21
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Advanced Member Group: Members Posts: 2,147 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
I just used Chris Foley's excellent rebuild kit on my leaky MPS. After removing the spider webs and varnish it all went together nicely. Chris gave me some great tips on getting an initial set. I think it is there but I don't have any experience with how a well tuned djet 2.0 914 should run. I suspect there is probably 150k or so on this engine although it could be lower, I doubt higher unless it was cared for very very well. Impossible to know with the dead odometer. Compression is great on all cylinders with no variability.
I took a little video of a drive, start up, corners, and two pulls to 60 (of various quality). After the first 40 seconds I opened my sliding rear window so you can hear the engine sounds better. https://youtu.be/Fi4vFCWhlCw |
jrmdir |
Oct 28 2021, 07:49 AM
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#22
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Member Group: Members Posts: 224 Joined: 13-May 21 From: Central Ohio Member No.: 25,544 Region Association: Upper MidWest |
OP, I hope this doesn't amount to hijacking your thread but it seems we're all in the same boat with this topic. I, too have just finished rebuilding my MPS using Chris' great parts and tuning kit. (When I got the car the diaphragm was toast and it ran rich.)
I made the mistake of buying a very cheap LCR meter on Amazon and had some scary results that I HOPE are the fault of the meter. In all of the write ups the inductance varies from around 1.5 down to .7 ish. On mine, the highest reading never got above .95. Even with nothing touching the operating rod (case apart) Coil resistance is great and inductance changes smoothly across the range, but it just reads too low compared to published data. Chris, then I read your seat of pants input here - set the outer screw to bottom out at around 5"Hg and put everything back together. And lo and behold the drivability is better than it ever was! Now I'm fine tuning and both the inner screw and the ECU knob make noticeable changes. But I'm not sure how to get the right balance. Idle is a bit too high even with the idle screw closed and the whiff test points to rich conditions. I've already ruled out other vacuum leaks and am still somewhat concerned about the low impedance measurements. As it seems that lowering the entire curve would add fuel across the range. But then it seems to drive very well and if I had a bad coil I'm not sure that would be the case. Any thoughts or advice would be appreciated. And if anyone knows of a reference inductor component I could use to spot check the meter it might help. Thanks, Ron |
ChrisFoley |
Oct 28 2021, 10:25 AM
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#23
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I am Tangerine Racing Group: Members Posts: 7,934 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None |
Idle is a bit too high even with the idle screw closed and the whiff test points to rich conditions. I would be surprised if the mixture is rich. Too high idle indicates too much air, ie. not enough fuel. Proper idle rpm should require some added air from the bypass. |
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