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RBL · Posted: Fri Mar 05, 2004 12:42 pm Post subject: stainless exhaust

Has anyone changed the complete exhaust system to include just two straight through mufflers? How loud would this be?

(I'm looking at putting this system into my mid-engined Porsche Spyder replica (1.7 8 valve sprint engine) so there would be one silencer for each bank of cylinders which would then go into a single tail pipe.)

I'm using Powerflow (www.powerflow.uk.com), anyone else used them for stainless exhausts?

I'd like to know what to expect before it's fitted and I blow my ears out!

Thanks Richard

Matt Stolton · Posted: Sat Mar 06, 2004 10:09 am Post subject: You may have odd problems

All the 33/sud/sprint exhausts feature some form of 4-2-1 manifold, and any silencers/boxes commonly effect all 4 pistons.

By having silencers working on just 2 pistons, before they join together, I think you could loose the pulse tuning of the original exhausts, which could loose you power and most certainly torque.

It would have to be a bit of a trial and see what happens I think, which isn't what you wanted to hear.

Normally, any nice exhausts I have seen have the manifold (4-2-1, or the 4-1 but incresingly difficult to find) a straight through cherry bomb type mid box, and some type of nice rear box. Supersprint is my preferred choice, simply for the build quality, and the lack of pressure it exerts on gas flowing through it.

I can't remember exactly why, but i think I have a number of mates slating and exhaust company beginning with 'P' for being over priced and poor quality. I shall ahve a word and check as to whether it is powerflow or not. Worst ways, Supersprint are blinding peices of kit, and they do bits and peices of a generic nature for you to build your own custom exhausts up.

I will also get you the number of a bloke who did an amazing full custom stainless exhaust on Mr G's 145 V6. The best news is it wasn't expensive, especialy compared to the price for a standard alfa full exhaust, or an aftermarket off the shelf equivalent. The workmanship was amazing and a really quality thought about exhaust.
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Regards

Matt

Ex Alfa 33 'GTA' (P4 with Knobs On)
Now cruising in a 166 3.2 Ti!!

rjbevan · Posted: Sat Mar 06, 2004 1:10 pm Post subject: Stainless exhaust

I have a steel exhaust on my Clan Clover (1.5 8V). There are 2 boxes across the back but there is also a cross over before the 2 pipes enter the boxes. I think this helps the extraction of gases from the engine. Since it came with this arrangement, I'm not sure if it could be improved.

One thing with stainless though is that it is noisier than steel.

Richard

Guest · Posted: Sat Mar 06, 2004 1:14 pm Post subject:

Thanks for the advice Matt. Due to the space available each side of the gearbox, I'm looking at one of the two options below.

So effectively it will be a 4 into 1 or 4-2-1 but with each cylinder head (ie 1&3 and 2&4) having it's own silencer. I understand what you say about all 4 cylinders not sharing the same silencer though - the engine would probably just have to be tuned accordingly - not sure yet. At the moment, my reason for going with Powerflow was due (hopefully) to lower cost and the fact that they are half mile away (helpful as the car is not on the road yet).

Anyway, hopefully the two pics below come out ok
Thanks, Richard
AAhh! Is it possible to attach a pic? (is a JPEG best?)

Eddie W · Posted: Tue Mar 09, 2004 10:39 am Post subject:

You might find a small balance pipe between the two exhausts a help(many v8s use this)
Regards Eddie
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