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Engine Overheating- Lack of Power-Missing

A friend of mine bought a very nice '75 2L 914 with a siezed motor. He had the engine completely rebuilt by AVP in Sacramento using German parts and installed it himself. The motor is stock with the exception of hydraulic lifters and appropriate cam to go with them. The motor has Pertronix points. He did a very thorough job taking care to get all the critical parts and tin back in place.

He happily started it up and ran it for a few hundred miles. It never really seemed to have the power it should, the engine randomly misfired at all RPM's, and it ran very hot. The oil temp guage would redline if he drove it for more then 1/2 an hour. He verified the temp with a infrared thermometer. The oil temp, according to the infrared thermometer, at the filter, drainplug, and cooler was 220 F at 50 degrees ambient air temp. The top of the cylinder temp was 390 F. The guage at this point was registering 1/8 below redline.

He's now at 4000 miles on the motor. It's still doing the same thing. If anything, the missing is getting worse. He's replaced the oil cooler, the CHT sensor, played with the timing, verified that there are no vacum leaks, triple checked all the tin, checked air flow, checked air flaps, checked oil pressure, and had it put on a diagnostic machine at a Porsche shop to check fuel mixture.

What gives?? Any ideas?? He's about ready to commit an unspeakable act against himself.
Old 04-08-2003, 06:42 PM
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does it still have the factory FI, if so is it D jet?

The worst thing for D Jet is a hydro cam! The worst thing for any TIV is a HYDRO cam!

Those temps are definately too hot for sustained low load situations. The head temps on my 180BHP 2316 with a stock cooling system run 350 all the time, oil temps run 225 after 5 miles of 5,000 RPM driving.

Sounds like he has a huge tuning issue (incorrect timing or mixture) or the engine was misconfigured.

Does he have the blueprints for the engine? if not he may never be able to get it tuned without a chassis dyno, which would definately help him out but would not be cheap.
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Old 04-08-2003, 06:48 PM
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Sounds like retarded timming to me too? Good luck.
Old 04-08-2003, 07:20 PM
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Sorry, I can't spell seized. I don't really like to use the word and rarely let it pass my fingers.

Yes, his car has the original D-jet. Excuse my ignorance, but what is a TIV engine? (throttle injection valve?)

He played with the timing. No help.

It seems like a lean mixture situation- you'd think if it was running too lean that his mileage would be spectacular. It's not.

I've driven the car. It's gutless.

I doubt very seriously that he has the blueprints for the motor.
Old 04-08-2003, 07:24 PM
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I'll almost bet the issue is with the D Jet and the hydro cam. The hydro cam is bad about delaying the valve opening and closing events andthat really messes with the firing of D Jet injectors.
A TIV engine in a 70-76 914/4 engine, or basically any 914 that did not come with a factory 6 cylinder.

Sounds like he has been a statistic. The things people do to get away from a valve adjustent!

The last hydro cam I installed in any engine was in 1998, I simply refuse to use them, and turn down work because I will not install them.
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Old 04-08-2003, 07:45 PM
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"TIV" is short for "Type IV", which is a specific type of aircooled VW motor. That's the type of VW motor in the 914s.

I don't know what the problem could be. Could be something like the compression being too low, or could be the injection and cam not working well together, or... Lots of possibilities.

Verify the mixture--you'll probably need a dyno, or at least a wide-band O2 sensor and meter--to see if that is the immediate cause of the heat.

--DD
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Old 04-08-2003, 09:10 PM
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