69 L36 Exhaust

[Paul J.]

Re: 69 L36 Exhaust

Patrick,
Our judging standard is how the factory built it, NOT how they could have built it. I think it is pretty well established that for the years you, Paul and I are interested in the OEM exhaust systems were not aluminized.

Hence the deduction for the non-factory finish. This has nothing to do with "date". Paul is double dipping, in my opinion.

[Terry M.]

Re: 69 L36 Exhaust

Hence the deduction for the non-factory finish. This has nothing to do with "date". Paul is double dipping, in my opinion.

I would agree if there was a date someplace on the exhaust system (like there is on tires), but on undated parts one has to either use only four metrics for judging originality -- I which case the configuration, finish, completeness and installation factors rate a 25% deduction for each, or one imputes a date based on the combination of configuration and/or finish and then makes the metric for each of the five factors 20%.

To use only four metrics and yet deduct only 20% for each gives a "free pass" for undated parts. That is not proper either.

[Paul J.]

Re: 69 L36 Exhaust

I would agree if there was a date someplace on the exhaust system (like there is on tires), but on undated parts one has to either use only four metrics for judging originality -- I which case the configuration, finish, completeness and installation factors rate a 25% deduction for each, or one imputes a date based on the combination of configuration and/or finish and then makes the metric for each of the five factors 20%.

To use only four metrics and yet deduct only 20% for each gives a "free pass" for undated parts. That is not proper either.

I understand. Why does the date factor have an equal weighting to the other four factors when it is taken from the combination of only two of them? Just a question.

[Floyd B.]

Re: 69 L36 Exhaust

Where does the part number fit in? For example if the intake manifold is correct in every way but has an incorrect casting number is that a deduction from configuration or completeness?

[Terry M.]

Re: 69 L36 Exhaust

I understand. Why does the date factor have an equal weighting to the other four factors when it is taken from the combination of only two of them? Just a question.

I suppose in some circumstance the completeness and installation could convey some information about the age (date) of the part, but I don't think that is the case here with early C3 exhaust systems, but I am open to hearing about it.

The basic NCRS judging system that uses all five metrics gives equal weight to each of the metrics, including date. We don't change that equal weight under any circumstances I can think of except when there is NO indication of date. Then the date metric goes away entirely. So the date metric is all or nothing. To paraphrase a renowned economist: "There is no free date."

[Terry M.]

Re: 69 L36 Exhaust

Where does the part number fit in? For example if the intake manifold is correct in every way but has an incorrect casting number is that a deduction from configuration or completeness?

The part number has nothing to do with it since the part number does not appear on the part, but perhaps you mean casting number since you used both terms.

If there is no difference in configuration except the different casting numbers, then one could argue either configuration or completeness, but since both have equal weight there would be no difference in the points outcome. Bottom line is it doesn't matter which metric creates the deviation unless the casting number difference also indicates a configuration difference -- which is often the case.

[Patrick H.]

Re: 69 L36 Exhaust

Patrick,
Our judging standard is how the factory built it, NOT how they could have built it. I think it is pretty well established that for the years you, Paul and I are interested in the OEM exhaust systems were not aluminized.

No, but was it done or was it technically feasible but GM was too cheap?

My point is that if it could have been done then the finish alone is not a reason to impart the date of the item.

Patrick

[Dale C.]

Re: 69 L36 Exhaust

Paul
The front pipes on a 68 BB #'s 3880401\3869583 (LH) and 3869584 (RH) don't have the wrinkles at the bends as do the mid's 3931829 and 3931830, do they? See pictures of them as service parts.
Dale

[Paul O.]

Re: 69 L36 Exhaust

Dale


Thank you for the photos of your GM service system. You have to understand that your service system may have some variations from the originals installed at the factory. Was the car an automatic or a 4 speed big block, small block also make a difference. Plus yours is a 1968 and Floyd 's is 1969 2 1/2" versus a 2" system makes a difference. I was telling Floyd of what the differences I saw for that system on a 1969. For a 1968 big block we have seen wrinkles on one side but not other and none at all. Yor pipes should be double walled if you could take a very close look at the pipes and see if there are very small holes in the outer pipe that go to the inner pipe. That is something I had noticed over the years and wonder what their purpose was.

Paul 18046