Exhaust mounting Commodore A GS 25H

[Brt]

Hello,

My name is Bartek, I'm from Poland and am currently finishing bringing my Commodore A GS Coupe to its original state. It's almost done, but I've encountered a problem with exhaust system.

The story is as follows: I've bought my Commodore about 2 years ago. As I bought it, it had 1.7 Rekord's engine fitted in (as a bonus I received original, totally rusted 25H engine that was laying unused in the garage for ~30 years).
I had no Commodore exhaust at all, and Rekord's one that was fitted in the car as I bought it - obviously doesn't fit original engine.

I've succeeded restoring the engine, I found new exhaust pipes:





but have problem with mounting it to the manifold.

There are 2 pipes, one of then has flange, and the other one one doesn't.

As far as I think, only the flanged pipe should be mounted to the manifold, and flangeless one should float (the weight of exhaust will keep it up)?
Browsing Victor Reinz's Catalogue ( http://www.reinz.de/pictures/PKW_OPEL_VAUXHALL.pdf - pages 966-967) I've found a gasket no. 71-23910-00 that (as I assume) should be fitted on the flangeless pipe to seal it, but with the gasket-ring on, the pipe doesn't fit the manifold.

Can anybody help me putting this all together?
How should exhaust pipes be mounted to the manifold?

Some photos would be nice

Thanks in advance,

Best Regards,
Bart

[Greaser]

Hi Bartek,

welcome to the forum!

The rear flange is originally mounted without any gasket. Due to the convex and concave form of the manifold and the pipe it should fit without blowing off. After 40+ years a little bit of exhaust sealing compound may become necessary, of course.
The front pipe is mounted with an oval piece of cast iron which fits to the front exhaust manifold. Its form looks a little bit like the flange mount which is permanently fixed on the rear pipe.
For mounting the front pipe, you have to put the cast iron on the pipe and then you need to place the gasket ring on the pipe. Then push the pipe into the front manifold.
For bolting everything together, I would recommend to start with the rear flange and finish with the front one.
Hope this helps!
Unfortunately I don't have any picture available...

Regards

Michael

[opelfreund]

Hi Bart and welcome.

This picture shows the mounting of the pipes:




Hope you will get a flange for the front pipe ...

[Brt]

@Greaser
@opelfreund

Thank You very much! Your clues (and photo) helped me a lot. Now everything's clear: I'm missing that cast iron part that comes on fromt pipe I hope I can find ne in my garage (if I won't... is it available anywhere? I don't think I can get new one... So I'll have to stick to ebay).

I have one more question:

As I'm still missing end exhaust, and I'm unable to get new one in Poland... Does anybody have exact measurements of end exhaust for GS (length, width, diameters... everything. The more data the better)?
With such info, I think I'd be able to have one made for me here.

Best Regards,
Bart

[Greaser]

You're welcome, Bartek!

Opel classic parts in the Netherlands offers reproductions. Maybe it is cheaper than reproducing a muffler on your own?
Here you go...

Cheers

Michael

[Brt]

Thanks for the link

As fas as I see, there's a set of 2 mufflers and an axle pipe, and I already have middle muffler and axle pipe. I can have end muffler made for me (according to dimensions I'll supply) for about ~100EUR, so it's about 1/4 of the price of the shop from link (including shiping costs), so it's worth giving it a try

So the question of dimensions and photos of rear muffler is still valid

Does anyone have these (or can measure/photograph it for me)?

Thanks in advence,

Cheers,
Bartek

[Brt]

Update: Opel Classic Parts seems to have end muffers sold separately too, so the problem of end muffer is solved (i think ).

Unfortunately I didn't succeed finding oval piece of cast Iron I was missing Does anybody have this part?



I don't think I can move on with the restoration without this small piece of iron (unless it can by replaced by anything, or there is any workaround for mounting front pipe?)

Best Regards,
Bart

[Commocruiser]

Sorry das ich hier in deutsch schreibe, aber kann die Befestigung des vorderen Rohres mal jemand übersetzen?
Wie wird das gerade Rohr mit dem ... befestigt?