3.0L engine swap

[Josh]

Compression test results:

Cylinder 1: 150+ PSI (needle just to right of hashmark)
Cylinder 2: 150+ PSI (needle just to right of hashmark)
Cylinder 3: 155 PSI
Cylinder 4: 160 PSI
Cylinder 5: 160 PSI
Cylinder 6: 160- PSI (needle just to left of hashmark)

looks perfect to me. Im sure bill is on it, but at this point it sounds like the timing (chains) are off.

[Farrar]

looks perfect to me. Im sure bill is on it, but at this point it sounds like the timing (chains) are off.

I'm pretty sure Bill double-checked before he put the valve covers back on.

For what it's worth, the engine idles fine apart from that very slight vibration at idle. Apart from that, it runs smoothly, and revs freely, all the way up to the redline.

I'm no engine timing expert. If the timing chain were off one tooth, would there be any other symptoms?

[Josh]

I'm pretty sure Bill double-checked before he put the valve covers back on.

For what it's worth, the engine idles fine apart from that very slight vibration at idle. Apart from that, it runs smoothly, and revs freely, all the way up to the redline.

I'm no engine timing expert. If the timing chain were off one tooth, would there be any other symptoms?

Besides low vaccum

The engine will hesitate when you get on the gas
Performance will be poor across the power band
Poor fuel mileage

A worn out timing chain tensioner could also give these symptoms.

[Drive Stainless]

Besides low vaccum

The engine will hesitate when you get on the gas
Performance will be poor across the power band
Poor fuel mileage

A worn out timing chain tensioner could also give these symptoms.

Bill measured the camshafts and found they are different from stock. Farrar's PO was Bobby Allison (https://en.wikipedia.org/wiki/Bobby_Allison). Is it plausible that a NASCAR driver would have the means to make a new set of camshafts that result in the vacuum signal being weaker?

[Josh]

Bill measured the camshafts and found they are different from stock. Farrar's PO was Bobby Allison (https://en.wikipedia.org/wiki/Bobby_Allison). Is it plausible that a NASCAR driver would have the means to make a new set of camshafts that result in the vacuum signal being weaker?

Those would be some pretty aggressive cams to drop it that much, you would be able to hear it I would think. Who knows though.

Is he comparing to another stock 3.0 cam? or the 2.8? Cause the 3.0 cam is certainly different than the 2.8.

[Drive Stainless]

Those would be some pretty aggressive cams to drop it that much, you would be able to hear it I would think. Who knows though.

Is he comparing to another stock 3.0 cam? or the 2.8? Cause the 3.0 cam is certainly different than the 2.8.

I think Bill is up to three 3.0L's now.

[Farrar]

Josh: Thanks for the diagnostic info. The engine seems to be suffering no other symptoms, but at the moment it also doesn't have the load of torque converter, axles, etc. to push against. Perhaps we will get more information when the engine is closer to normal operating conditions.

Matt: I thought the comparison Bill made was to stock 3.0L camshafts, not stock 2.8L camshafts. Did I get that wrong?

I think #2613's 2.8L engine, when it was healthy, pulled about 18 inches of vacuum. I know other engines pull more in the range of 20-21, but I never gave it much thought.

[Drive Stainless]

Farrar: Check with Bill, but I believe he compared with the 2.8 L camshafts to understand that they were not the same and also compared with 3.0 L camshafts to understand they were close enough.

[louielouie2000]

Bill measured the camshafts and found they are different from stock. Farrar's PO was Bobby Allison (https://en.wikipedia.org/wiki/Bobby_Allison). Is it plausible that a NASCAR driver would have the means to make a new set of camshafts that result in the vacuum signal being weaker?

I drove and rode in Farrar's car quite a few times when it was still running its original 2.8 before and after carb conversion. It definitely didn't have performance cams. His engine also didn't run any less smooth than any other "stock" DeLorean. It was by far the slowest DeLorean I've ever driven, though. A 1960s Beetle could probably have outrun it. Something definitely wasn't right.

Oh, and Farrar- Bill advanced the timing on my second DeLorean that much once too. Definitely have him dial it back.

[Farrar]

Bill was able to get the engine to pull 13 inches of vacuum at idle by advancing base timing up to 18 degrees.

This is incorrect! Timing is at 16 degrees, not 18. Apologies for the error.

Curiosity aside, it doesn't matter to me what kind of camshafts are in this engine, as long as they work. Remember that this car's previous engine slowly died and refused resuscitation. Apart from a few failed attempts by me to get it started, swapping out fuel from the tank, and pushing and pulling it this way and that, the car did absolutely nothing for almost two years. I'll be happy to have an engine that functions, regardless of "performance."

The distributor is an AMC/Jeep externally; the internals - counterweights, &c. - are brand new. If timing advance needs to be adjusted, the time for that will be when the car is road-tested. That won't be any time soon.