70-71 1st Design Exaust Tip Welds, Help!!

[Steven G.]

ACCORDING TO NCRS 70-72, 4TH EDITION TECH. INFO. MANUAL + JUDGING GUIDE, THE FIRST AND SECOND DESIGN EXAUST TIPS WERE SIMILAR, OTHER THAN BOTTOM WELDED SEAM FOR 2ND DESIGN AND SMOOTH BOTTOM WITHOUT A SEAM ON 1ST DESIGN. DOES ANY MEMBER OR JUDGE KNOW HOW PIPE IS FASTENED TO FLAT RECTANGTULAR BACK OF TIP? WOULD BACK BE CRIMPED AND SPOT WELDED OR CRIMPED AND A FULL BEAD AROUND PIPE OR SOMETHING ELSE?

[Terry M.]

Re: 70-71 1st Design Exaust Tip Welds, Help!!

Too late at night for me to go look, but working from memory the first design back is folded inside the rectangular tube and welded with a bead. NO spot welds.

BTW: We didn't have the space to teach welding or mechanical processes in the TIM&JG, but "seamless" tube is not really seamless. There is a welded and polished seam that is nearly invisible, but unless the tips receive a show chrome finish (who would do that? ) the seam is visible if one looks at the right angle. That is easier done when the tip is off the car.

[Jim T.]

Re: 70-71 1st Design Exaust Tip Welds, Help!!

In the 80's I was buying parts for my 68 and 70 from the local Chevy dealership. In the earlier 80's new exhaust spouts were not available for my 70 although I bought new ones for my 68. I purchased a pair of stainless steel spouts for my 70 from a Corvette parts vender. I am still using them. Later in the 80's the spouts became available for my 70.
I bought two of the spouts for my 70. I have not opened the boxes to look at them in all these years. I went looking in the garage specifically earlier this evening to find my spouts after reading earlier posts about the spouts/tips. I was also looking for the spark plug heat shields and the attaching bolts that I removed from my 70's engine when I removed it to install my ZZ crate engine. I did find my 70's ignition shielding, all 7 pieces of it. I will continue my search tomorrow for the spouts and spark plug heat shields.

[Chuck S.]

Re: 70-71 1st Design Exaust Tip Welds, Help!!

Too late at night for me to go look, but working from memory the first design back is folded inside the rectangular tube and welded with a bead. NO spot welds...

That is my recollection for the second design as well. There were no spot welds. The back of the tip is recessed slightly into the shell, and is continuously fillet welded around the inside of the shell.

When you look inside the tip, the flange that is folded inside, as Terry described, is generally sagging down from the outer shell on well-used tips. I not sure if they were like that from fabrication, or the deformation caused by exhaust heat, corrosion, wear and tear, etc. The second design has the butt weld seam on the bottom of the shell.

[Dennis D.]

Re: 70-71 1st Design Exaust Tip Welds, Help!!

1st design if this helps...

[Steven G.]

Re: 70-71 1st Design Exaust Tip Welds, Help!!

Dennis, Thanks For Your Time Posting Pics., A Picture Is Worth 1000 Words, This Should Answer All Design Questions About 1st Design Exaust Tips. Steve

[Pat M.]

Re: 70-71 1st Design Exaust Tip Welds, Help!!

BTW: We didn't have the space to teach welding or mechanical processes in the TIM&JG, but "seamless" tube is not really seamless. There is a welded and polished seam that is nearly invisible, but unless the tips receive a show chrome finish (who would do that? ) the seam is visible if one looks at the right angle.

In fact, on one of my 1st-design tips the seam had a few little pits which you can still see under the chrome.

[Terry M.]

Re: 70-71 1st Design Exaust Tip Welds, Help!!

Nice tips

I just couldn't resist that.

[Alan S.]

Re: 70-71 1st Design Exhaust Tip Welds, Help!!

Hi Dennis,
I agree with Terry...NICE tips. I notice the pictures are of just 1 !!!, I sure hope there's 1 that matches on the other side.
Thanks very much for showing a very nice original part up-close.
Regards,
Alan

[Jim T.]

Re: 70-71 tips

Reference my previous post, I found the two exhaust tips I bought for my 70.
I discovered I had opened one of the boxes and looked at the exhaust tip many years ago. This one came in a part box with #3974660 on it. Pretty nice looking chrome finish on the outside. This is the tip for the passenger side. On the bottom of the tip when installed is a stamping GM3974660 with a W stamped below the number. The tip has two slits cut in the pipe piece. This pipe is attached with spot welds and the other two pieces are also spot welded together. Do not know the guage of the steel, however it is a very sturdy tip. The seam in the pipe is easily seen.
My other tip box part #3974659 had not been opened until this afternoon. I opened it and found an exhaust tip that the chrome finish was not as attractive as the above piece but did have a chrome finish. The construction appears to be the same guage metal and only has one slice on the bottom of the pipe and has the cutout on the top of the pipe. It is spot welded together as well. On the bottom it has the very same stamping, the W and the GM3974660. Suprise, suprise, although the part box label showed the part number for the drivers side, the tip inside is for the passenger side and has the passenger side part number stamping. I should of looked inside of both boxes at the parts counter when I picked them up about 19-20 years ago and reordered.

[Steven G.]

Re: 70-71 tips

Exaust tips having part #'s are service replacements. These tips are spot welding as you mentioned, however, they would not be correct for 1970-1972 according to ncrs tech. + judging guide.

[Terry M.]

Re: 70-71 1st Design Exaust Tip Welds, Help!!

And the W indicates the manufacturer -- Walker

[Harmon C.]

Re: 70-71 1st Design Exaust Tip Welds, Help!!

In the top picture I see the tube spot welded into body of the tip and on the bottom picture I see a bead of weld. Could you post a picture of the sides to see where the weld stops or if it is as it looks. If their are more examples please jump in.

[D S.]

Re: 70-71 1st Design Exaust Tip Welds, Help!!

Please refer to an update post by Pat Moresi regarding Richard Fortier's protoype of the 1st design tip which includes photos of it. Email Richard with your comments. richfortier@chartermi.net

[Stan F.]

Re: 70-71 1st Design Exaust Tip Welds, Help!!

These first design tips are on an exhaust system removed from a very low mileage car back in 1970... They have never been removed from the mufflers.









Regards,

Stan