Replacement Exhaust

[kev131]

The back box on my Abarth exhaust on my Sport is blowing so I need to take some action. I think my options are to:

(1) Repair the rusted our section of the box and keep what is otherwise a working Abarth system. Feels like a short term throw away solution.
(2) Replace the rear section with a new after market section. I'd lose the twin chrome tips and may only get a few years before having to do the job again.
(3) Replace the entire system with a stainless steel system as it's quite likely that other parts of the existing system will go in the future.

I'm veering towards the last option and have a price for a Long Life system to be customer made - The boxes, inside baffles and pipework will all be stainless steel. Total cost plus fitting is ?450.00 incl VAT but excl the manifold. The supplier is an agent for Long Life but hasn't done a 131 before. He's offering a mid noise level solution.

I'd be interested in what other people have done on their Sports and general views on what the best course of action would be.

For example should I copy Simon's solution with the pipes coming straight from the engine...or keep the existing manifold?
I like twin polished tail pipes but some people have gone for a single bigger bore pipe. Which is better for sound...?

I hope Simon doesn't mind but I've posted up some close up shots of the Long Life job done on his Abarth, which I always think sounds superb burbling through narrow streets in second gear.

[mirafioriman]

If you're planning to keep the car long term (which I presume you are) then it's stainless all the way in my opinion. After that it's personal choice I think. Loud exhausts are ok for short periods in my opinion but if you're using the car regularly or for long journeys become tiresome. That's just my opinion though others may disagree

[c.a.c131]

Stainless steel is the only way to go, it's costs more but it's worth it in the long run Nick has a hand made Stainless steel system on his Racing & it's very nice. A single pipe I think sounds better then twin pipes they sound like the exhaust has a blow in it.

[jasonh131]

keep the cast manifold , tubeler manifold is most of the cost ,and go from the cast maniflold flange to the back .

[sid131]

My 131 racing has a wrapped 4 into 2 into 1 steel manifold mating to a hand made custom 316 stainless system 2" with no middle box, has a nice sound not too loud just perfect
?450 is cheap you wouldnt get this system for that price

[kev131]

Thats a lovely bit of kit Nick - Thanks for the pics. 

My car isn't to the same standard under the hood so I'll probably keep the manifold (which is where I guess some of your cost went).

How did you make sure the installation didn't resonate/vibrate?

On the noise front, would you do a long motor way cruise at say 90mph (for hours on end) without it becoming annoying/tiresome and causing a potential headache?

[sid131]

Kev it has 3 rubber mounts & the noise is ok wouldnt be a problem with motorway crusing 
anyway the car has dynamat & fatmat everywhere all you can hear is the stereo!

[Thotos]

My custom made exhaust is also a Longlife. Details at http://www.131mirafiori.com/smf/index.php?topic=3627.msg27874#msg27874

I prefer a single tail pipe on a 131 but I could have any number of shapes and sizes including twin pipe; they'll simply fit whatever you want from a large selection at the end of the silencer. You also have the choice of single or twin silencers. I considered single rear silencer but convinced to go for two by the fitters and I think they were right. The manifold like Simon's will cost as much as the rest of the exhaust or even more. I already had a Janspeed 4-2-1 so kept that and had the 2" pipe fitted over the downpipe instead of in it. Fiat cust iron manifolds are actually very good and flow well so I'd suggest you keep the manifold.

[simon131]

Wow Kev, when did you take those pics of my exhaust?

I put the stainless exhaust on my Abarth virtually from Day One of my ownership. I decided stainless for a couple of reasons - longer life than mild steel and difficult to obtain 'standard' Abarth parts in the UK. It has proven to be a good investment.

Back in 2004 the full system, head to tail pipe, cost me ?750 all in, which was quite expensive at the time, but Long Life have been good to their word with respect to lifetime warranty and have twice sorted out the system when it was first fitted - once to fit a second silencer box (as it was just too noisy for me) and again to sort an issue with the wrong fixings being used at the connection between the down pipe and first straight section - both at no additional cost to me. I'd happily recommend them.

My system is slightly larger bore than standard and with one tail outlet - cos I prefer the neater single pipe look.

[kev131]

Hotel car park at Bad Bentheim Si....We were just kicking tyres and I knew this day would come...

Theo - can you remember what the arguments for and against the single box were?

[Thotos]

Theo - can you remember what the arguments for and against the single box were?

I thought I'd go for a single box to get a 'deeper' sound, lower cost and a bit more performance but the fitters convinced me I was wrong on all counts  They said a single box (which would mean a very long pipe) would be too loud and cause the pipe to resonate. They said it would be better to fit two smaller silencers than a single bigger one. There would be negligible cost difference and there wouldn't be any performance gain/loss as the silencers they fitted were straight through with no restriction and as I went for a 2" pipe I had plenty in reserve. A rule of thumb says "one inch per 100bhp" so my exhaust should be good for 200bhp.

[kev131]

Thanks Theo...which leads me nicely to my next consideration - How big should the pipe be for my bog standard 115bhp (less the ravages of time) bog standard motor?

Maybe 1.25 inches - Will I get any benefit from a bigger bore....? Sound, power...etc

[Thotos]

I wouldn't go for anything smaller than 1.5 inches. The size of the pipe may be determined by the size of the downpipe if you don't have that replaced. Once you go to 2 inches or above you'll start running into space problems. I had the pipe flattened on mine to clear the prop brace and that's not very good. But my car is too low so I couldn't have the exhaust any lower.

I thought your car had modified cams and a few other Horrman tweaks so it's not really "bog standard".

[kev131]

I thought your car had modified cams and a few other Horrman tweaks so it's not really "bog standard".

Gee - I'm not aware of any internal improvements to my engine...but it does go well so who knows. It's kept your car honest a few times!! 

It did have a lot of ancillary engine tweaks which have all been removed except the oil cooler. At one stage it had three oil filters!!

The most obvious Hormann tweak was the boot spoiler you so envied...but which is also now removed. 

[sid131]

All you need now is a richard grant spoiler & a sexy louvre lol! 
twin exit upswept white hooker & waken the dead Kev!!