Brake line

[Bob I.]

The front 1970 replacement crossover brake line, was bent different on the left side. it's the lower line in the photo. From the center over to the right side, the line fit was correct. The line was made to part #3974702. I don't know which of the configurations is correct.

Bob

[Joe L.]

Re: Brake line

The front 1970 replacement crossover brake line, was bent different on the left side. it's the lower line in the photo. From the center over to the right side, the line fit was correct. The line was made to part #3974702. I don't know which of the configurations is correct.

Bob

Bob-------



I think that part of the problem will involve the fact that I don't see how the new line is going to work with the brake line clamp point used by the original line.

By the way, your upper a-arm bushings are not correct for a 1970. They are 100% functional but not configurationally correct for 1970. There should be a rubber "collar" seen at the inner end. The style you have are correct for 1973-82 Corvettes. It's no big deal, though, and I sure wouldn't replace these bushings now just to gain this nuance of original configuration.

[Alan S.]

Re: Brake line

Hi Bob,
My mid-January 71 has the brake line in the lower position.
There is a hole in the frame for the brake line clip bolt in the lower position in ADDITION to the upper hole seen in your picture. It would seem your line was intended to run in the upper position, or is the lower bolt hole hidden?
Regards,
Alan

[Chuck S.]

Re: Brake line

...By the way, your upper a-arm bushings are not correct for a 1970. They are 100% functional but not configurationally correct for 1970. There should be a rubber "collar" seen at the inner end. The style you have are correct for 1973-82 Corvettes. It's no big deal, though, and I sure wouldn't replace these bushings now just to gain this nuance of original configuration...

Joe, do you happen to know who actually manufactures the correct appearing reproduction bushings? Do you have any reservations about the quality of the reproductions versus original GM NOS stock (without the exposed collar)? In other words...if you happened to have NOS versions of the later service replacement bushings in your stash, would you use those, or order the correct appearing repros?

[Chuck S.]

Re: Brake line

The front 1970 replacement crossover brake line, was bent different on the left side. it's the lower line in the photo. From the center over to the right side, the line fit was correct. The line was made to part #3974702. I don't know which of the configurations is correct...

Since my first post on the brake line was full of incorrect observations and premature conclusions, I've deleted it to eliminate confusion.

I just double-checked my late 70 frame, and there are three holes just as your picture shows. The small center hole has also had a self tapping screw installed. My late 70 frame DID had a clip at that location.

Examination of the picture reveals that your brake line seems to have been manually deformed to conform to the clip location (very slight overbend on the LEFT side of the photo).

I think I understand why your line had to be deformed to fit the clip...the clip should be mounted with the screw head ON TOP...i.e with the line running below the clip. (See AIM UPC5, Sheet B1) That change should eliminate any problems with your crossover line not fitting properly, since it will lower the line position about 1.5 inches.

You will want to double-check that this positioning keeps the line firmly in contact with the frame, and does not allow vibration or rubbing against the frame. If the manual bend is original to the car, that's the only reason I can see the factory would run the line above the clip.

[Joe L.]

Re: Brake line

Joe, do you happen to know who actually manufactures the correct appearing reproduction bushings? Do you have any reservations about the quality of the reproductions versus original GM NOS stock (without the exposed collar)? In other words...if you happened to have NOS versions of the later service replacement bushings in your stash, would you use those, or order the correct appearing repros?

Chuck------

I do not know what firm manufactures the reproduction bushings. I THINK it is Harris, but I don't know that, for sure. I need to get some and carefully inspect them. If they are of Harris manufacture, I would have no qualms about using them. If they are not identified as Harris, I might still use them providing a careful inspection convinced me that they are a quality product.

If I was not convinced of the above, I'd use the GM SERVICE bushings (also, PRODUCTION for 73-82), GM #401267 as manufactured by Clevite. These bushings remain available from GM. However, the same bushings are usually supplied under other brand names like Moog, NAPA, etc.

[Bob I.]

Re: Brake line

Yes, it appears the original lines configuration is altered. I bolted up the new line with the clips position as the AIM. Their is 2" difference between the center of bolt hole in the clip, by the bolt hole in frame.

Bob