[Barry]

Can anyone tell me what spec exhaust the carbed 308s came out of Maranello with?

I've been looking at a few recently, some have just the single pipe (which I quite like) and others have the 4 branch exhaust system. But on all of those with the 4 branch exhaust systems, there is a piece of the rear bumper cut away on the left side (where the single pipe would be) but not on the right - which would indicate to me that this is an aftermarket add on and that the car originally left the factory with a single exhaust pipe.

Does anyone know the definitive answer? Were any carbed 308's manufactured with 4 exhausts, if so what years etc?

[tazandjan]

Barry- Two data points for you. 78 Euro 308 GTS, stock except for roof spoiler, photos taken in 1981/2, with OEM four tailpipe exhaust.

Photo taken on Maranello production line in Oct 1983 with 308 GTS QV with four tailpipe exhaust.

Looks like the same exhaust to me.

[Mark456M]

Don't know dates but many 308's came with single rear pipe. My '79 GTB had a single pipe. Only one cut out in rear valance.

[tazandjan]

Mark- Good to see you here. Note on those two 308s above, one of them my old car, there are no cut-outs in the valence. The tailpipes are below the valence.

[Barry]

Originally Posted by tazandjan

Mark- Good to see you here. Note on those two 308s above, one of them my old car, there are no cut-outs in the valence. The tailpipes are below the valence.

I noticed that Terry. There must have been some OEM 4 branch exhausts so. I'd love to find out the history and reasons behind the move to a single exhaust and then subsequent move back to the 4 branch. I wonder could it be anything to do with Euro vs US models?

[tazandjan]

Here are the images from the parts catalogs for the 1976, 1980, 1981 GTBi, and 1985 GTB QV cars. The 76 and 80 catalogs show the single outlet exhaust, but we know the four outlet was available because mine came with one from the factory. Was there a sports exhaust option? Were different exhausts fitted to GTS cars than GTB cars?

We should ask Brian Crall. He is writing a book on the 308s.

[Barry]

Interesting. The plot thickens...

[tazandjan]

Barry- All the owners manuals drawings for the Euro and early US 308s show a single exhaust, but the 1978 US OM 150-78 shows a four pipe exhaust with a heavy valence, likely to protect the body work and lights from the heat of the catalytic converters. So the catalytic converter versions from 1978 on and the GTBi and GTB QV all had four tailpipe exhausts.

Why some non-catalyst GTB/S cars had four pipe and others single pipe exhausts is the big question.

Could it be just as simple as using the 308 GT4 exhaust on some Euro cars? I note the GTBi and Mondial 8 share the same exhaust system, as did the QV and Mondial QV.

[Mark456M]

Taz, I think the GT4 exhaust is different as it formed part of the rear valance and was shaped as a result. The GTB/GTS had a more rounded shape.

[tazandjan]

Mark- If that drawing is accurate, you are correct. The GTS QV exhaust in the factory shot definitely has a round shape, and judging from the front side marker lights, it is a US spec car.

[barcheta]

Just to add to the confusion, in the US all OEM QVs in addition to the valence all had the 4 tip exhaust. I've never seen a US carb car without this same set up. On euro cars and 83 US the front and rear headers both emptied into the muffler but I beleive the US cars also used two individual cats. On 84/85 US cars they emptied into a single catalyst then into the muffler. The OEM manaufacturer back then was Ansa. Apparently, the Stebro exhaust is a close facimile of the original Ansa.

[Mark456M]

According to one of my sources, all Euro carb cars came with a single pipe exhaust. The 4 tip was an option.

[tazandjan]

Mark- That would make sense and matches the parts book.

My GTS supposedly had the 285 hp engine with the P6 cams, etc, so maybe the four tailpipe exhaust came with the package. It was a very strong 308, now somewhere in the US on an EPA waiver, so no smog gear, and, when imported by Steve Forristal, no A/C. You could buy an A/C kit for only about $1K back when I sent it to Steve in September 1983, so it probably has A/C by now. I remember Steve advertising it as the fastest stock 308 they had ever seen.

[Mark456M]

My 1980 GTB/GTS parts book lists only one exhaust. Picture shows the twin muffler single pipe box. There is a special for AUS cars but it's still a single pipe.

[Barry]

So general line of thinking is:
All Euro carb 308s were manufactured as single exhaust cars... Unless...

1 it was upgraded to 4 branch exhaust at order and built as such in Maranello, or
2 it was converted to 4 branch exhaust at some point after it's original sale (and this would be evident by only one 'cut out' in the rear bumper/valance.

Seems to be the general consensus?

[Barry]

By the way, thank you for all the replies and general sharing of knowledge.

[Mark456M]

Barry, I think you've got it! Just to add to the confusion, my GTB has a 4 tip exhaust now and I've filled in the cut-out.

[Barry]

Originally Posted by Mark456M

Barry, I think you've got it! Just to add to the confusion, my GTB has a 4 tip exhaust now and I've filled in the cut-out.

I think I'd do the same if I had a 4 tip 308 too.