S6 Decats - differences between power, RG, ACT etc?

[Zippee]

I'm considering a set of decats for my 350 and looking around ACT offer them for £175 plus VAT, whereas Powers are £290 plus vat. What are the differences if any asd I thought they were just steel cones? I'm leaning towards the ACT ones mainly due to cost but is that a false economy?
For reference I have the JP box on the back so will be properly loud but I don't want tinny.

Edited by Zippee on Thursday 26th May 19:35

[DumDum]

Wouldnt have thought so, they are just empty pipes afterall. Some talk of flow on some sights, etc. I really cant see it makes any difference whatsoever.

[gilbo]

The ACT ones are a really good bit of kit and are definitely not a false economy. I was over the moon with the fit and finish of mine and they perform superbly too.

[clive f]

flow is important, whichever ones you buy, you want the conical section to be as long as possible, thus giving a smoother flow into the exiting exhaust pipe.

[DumDum]

It would be on a turbo car, but seeing as though removing the restriction of the cats on these cars loses power, then I really cant see how it matters in the slightest.

[dpd3047]

ACT decat pipes are the ones to go for i fitted a set to a T350 gained 8 BHP
10 FT LBS of torque.

[Mattt]

Why are they still conical, and not a straight bit of pipe? I assume the pre and post sections are straight pipe.

[duff-man]

Because you are trying to get three exhaust header pipes from the cylinders (manifold) into one exhaust pipe. my understanding is that a cone is the most efficient way for flow of doing this.

[nightSpirit]

Another thumbs up for the ACT items...took 2 days to arrive aswell.

http://www.youtube.com/watch?v=v5vnyidG180

My other thread earlier this week showing the sound difference with these fitted.

The shape of them is conical and smooth so I think the flow from the manifold is well catered for.

[UFO MATT]

ACT on mine as well, superb product and great sound on the over run :-)

[bobd]

JP exhausts make them for power and ACT I believe.
The tapered cone should give you a better torque reading and power curve, whereas a cat shaped one with that sudden reduction in diameter will more than likely give reduced torque. I would like to see some dyno graphs for comparison.

[UFO MATT]

I can only tell you what my car made before and after live mapping but the decats were already on.

[RedSpike66]

Mattt said:

Why are they still conical, and not a straight bit of pipe?

I think Dyson found some advantage with conical shapes and airflow... ;-)

UFO MATT said:

I can only tell you what my car made before and after live mapping but the decats were already on.

Go On then...

[UFO MATT]

Well we only had it done a couple of weeks ago and the only mods we have are the carbon trumpets,ACT decats and the RG rear exhaust. Before mapping it made 345 bhp and 281 lbf torque,after live mapping it made 396.2 bhp and 344.0 lbf so a vast improvement and it feels wonderful to drive now. This result was at the rolling road open day last weekend and only a short time later a Power 4.3 tuscan was on the rollers and made 392.2 bhp and 323.0 lbf .

[BCA]

UFO MATT said:

Well we only had it done a couple of weeks ago and the only mods we have are the carbon trumpets,ACT decats and the RG rear exhaust. Before mapping it made 345 bhp and 281 lbf torque,after live mapping it made 396.2 bhp and 344.0 lbf so a vast improvement and it feels wonderful to drive now. This result was at the rolling road open day last weekend and only a short time later a Power 4.3 tuscan was on the rollers and made 392.2 bhp and 323.0 lbf .

Same open day that FUBAR's Cerbera that normally runs circa 420 made 458bhp?? I'd take it with a large shipment of salt.

[UFO MATT]

There are always going to be debates about RR figures, others that day said they were down on power reading and that surrey RR showed more. I will take it to another for a compaird reading some time and then take the average I suppose.

[RedSpike66]

The important figure is the substantial increase in both BHP and Torque, assuming both sets of figures were obtained on the same rollers on the same day (i.e about an hour apart allowing for the re-mapping time). Impressive gains for three straightforward mods imo.

Well done - you must be chuffed and must be able to feel the difference... :-)

[UFO MATT]

RedSpike66 said:

The important figure is the substantial increase in both BHP and Torque, assuming both sets of figures were obtained on the same rollers on the same day (i.e about an hour apart allowing for the re-mapping time). Impressive gains for three straightforward mods imo.
Yes the results were on the same rollers with about the same ambient air temp so very pleased. It was like a completely different car with torque coming in much sooner and smoother. On the same day another unmapped sagaris with cats made 349 and 280, about the same as ours made with the decats on so it shows to get the most out of decats it's best to chip or map. Hope this helps everyone :-)
Well done - you must be chuffed and must be able to feel the difference... :-)

[Zippee]

Out of interest who did your mapping and how long does it take and cost? I've an invoice in my history from the previous owner 4 years ago showing a new chip from power, the invoice states it's a de-cat chip so I know I can save a little cash there.

[UFO MATT]

Paul at Austec racing did the mapping for me, we got there at 9am and came out a little after 2pm. He removed the air box first and fitted the carbon trumpets then he did the live mapping while anothe drives on the rollers. He is so convinced he can make the car far better than standard that if you are not happy you don't have to pay!! Can't say fairer than that. The cost was £750 for the mapping. I can't recommend it enough, the car was transformed.