[Half-Inch Stud]

So, all my 68 LeMans/GTO experience shows the rear bumper getting bespekled with grime.

Air dynamics probably dictate aft backwash from the aft wake produced at speed.

Anybody have a driver that the Rear Bumper and tail lenses stay super clean?

[OCMDGTO]

Ron Johnson sold me an NOS bumper for my old 70 GTO 25yrs ago and said make sure you keep it waxed, no problems after that.

[Half-Inch Stud]

70 has Splitters and lower valence....i dunno.

[DavesGTO]

I have never given this any thought before and it certainly isn’t original but maybe the ‘72 tailpipes?


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[Greg Reid]

I just have turn downs on mine HIS...Been that way since 2011 or so...never noticed any problem with the bumper or tail lamp staining...

[dataway]

Jeez that car has come a long way

[Greg Reid]

LoL...you don't know the half of it dataway...

[OCMDGTO]

Hard to believe that's the same car, Greg!

[Greg Reid]

Yeah, here is a pic of when I first got it and as I got it. I was pretty let down when I sanded that primer off the roof and found expanding foam filling all the rusted away sheet metal!

[Half-Inch Stud]

Greg, car looks great, and good downturn idea and datapoint.

davesGTO, good looking side-out and good datapoint.

since I have tails straight out back, the downturns will be easiest to try.

[Greg Reid]

I used the Pypes turndowns HIS...just fyi

[Formulajones]

Originally Posted by Greg Reid

I just have turn downs on mine HIS...Been that way since 2011 or so...never noticed any problem with the bumper or tail lamp staining...

That's actually very close to how the factory had the tailpipes if the chrome extensions weren't ordered. If you had just a slight angle cut on those you could mimic it exactly.
My father still has his original resonators for his 69, which actually formed the tailpipes, and they are turned down with an angle cut on them, so over the years with different systems on the car, he's always duplicated that appearance with the tail pipes. Never any staining or noticeable issues with the chrome on the back bumper.

[Half-Inch Stud]

Memory is lacking on factory 68 GTO tailpipe cut. seen all the walker replacements though.
I recall how I had 1 pipe down turned, while the other was straight-out; dumb look for a pair of tails replaced in 1982. complaint was met with dumb looks.

I can understand how the slight downturn may make a big difference when compare to my Pypes (auto correct turned Pypes into Pepe's now that's funny) Straight-out, Straight-Cut tails.

[Formulajones]

Here's a picture of dad's car back when I was painting it. These are turned down at the tip about 45 degrees, then I copied the slash cut from his original resonators so it appears as the car did when he bought it new (albeit larger pipe now). Best pic I have at the moment.

[Greg Reid]

Originally Posted by Formulajones

That's actually very close to how the factory had the tailpipes if the chrome extensions weren't ordered. If you had just a slight angle cut on those you could mimic it exactly.
My father still has his original resonators for his 69, which actually formed the tailpipes, and they are turned down with an angle cut on them, so over the years with different systems on the car, he's always duplicated that appearance with the tail pipes. Never any staining or noticeable issues with the chrome on the back bumper.

That's actually what I was TRYING to do Larry. The Pypes turndowns were as close as I could get without cutting and welding. Always liked the look of the standard setup on these cars better than the chrome tips.
Pontiac did not have the best design for chrome tips in my opinion. Well, with the exception of the splitters and the second gen TA's.

[Interceptor]

Same issue on my 70, with the slash-cut dual tips. I think unless you use the turn-downs you are stuck with exhaust residue on the bumper. They would look fine on a 68, without the lower valence.

[Half-Inch Stud]

Yea the 70 Splitters are the bomb on 68-72.

45* Downturn with angle cut is functional and styled.

[68ragtop]

So what about those optional tailpipe adaptors? I bought them with my 68 Gardner system, but haven't installed them. I think they were designed to fit the chrome tips? I would have to dig them out.

[Half-Inch Stud]

My PYPES tails come straighten get out. Cut-back for downturns could happen.

[68ragtop]

Here is the Gardner system I have. Looks low in the second picture, but the picture is taken below rocker height. You can just see it if its on the ground & the cut edge is just below the rear bumper. I have never seen an original, so I am just assuming its similar?

68RT

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