Custom Decat

[Hurdy]

Put this on the Edition 30 on Monday and thought you guys might like to see the difference it makes to the car as it is basically the same set-up for a Cupra with a Milltek too.

A custom decat that can be swapped with the newly flanged cat section within 15 mins, without having to mess about taking the downpipe off from the turbo!!

Before...

After...

The car has just been on Noble's dyno and last time out made 378.6bhp and 353.6lbft before the decat section was put on

This time out the car made 383.1 bhp and 358.1lbft

So an increase of a whopping .....4.5bhp and 4.5lbft

Doesn't seem like a lot for the work done, but the "devil is in the detail" as they say.

Torque is over 340lbft all the way from 2950rpm to 5750rpm

Before torque was over 340lbft at 3400rpm to 5100rpm

Power now hits 200bhp at 2850rpm and before power was 110bhp at the same rpm

The only downside is that I need to revise the fuelling setting as there is now a dip at 5750rpm, recovering at 6250rpm.

The dyno man said if the dip could be tuned out, it would have probably gone to 390bhp

Oh, for those with a Dyno Dynamics accuracy fetish, I've been told that generally the differences are 2-3% higher at Nobles. This equates to 371bhp with a 3% correction factor.

So, now I know that the car is relatively healthy as before, I can press the "GO" button on the next step of mods - race cams

 

[RobH]

Dont think ill be doing this but makes a big difference low down and would be intersting to see how much top end once fueling is sorted, that then might change my mind on this , bet the noise is ridiculous .

 

[robjnr]

What other mods you got to achive this figure matey?

 

[Hurdy]

What other mods you got to achive this figure matey?

Full bolt ons and REVO stage 2+.

Every bolt-on and modification makes a difference, maybe each one is only slight, but they add up

eg

Denso Iridium over OEM plugs

Millers "extra cool" coolant over OEM coolant.

Autotech over APR HPFP

EVOMS over DBILAS for the intake

etc, etc.

Even the VF engineering mounts make a small difference in the power transmission.

The "pre decat" run was done with Millers Octane booster and so was the "Decat" run after.
the octane booster and tweaking the REVO settings made 12bhp difference alone.

366.3bhp on normal V-Power and 378.6bhp with the octane booster and REVO settings tweaked.

 

[Al]

You got sound clips yet mate? How does sound now compare with sound before? Also, what will you be doing to resolve the fuelling issue?

 

[Knight_Rider]

I've got a 3inch Decat downpipe on my FR, getting a camcorder at xmas so will try post some clips. Deeper note on start up and idle some more pops and bangs too. Having my Revo altered in the new year to maximise it.

 

[Tfsi_Mike]

Full bolt ons and REVO stage 2+.

Every bolt-on and modification makes a difference, maybe each one is only slight, but they add up

eg

Denso Iridium over OEM plugs

Millers "extra cool" coolant over OEM coolant. Hmmm

Autotech over APR HPFP Really???

EVOMS over DBILAS for the intake

etc, etc.

Even the VF engineering mounts make a small difference in the power transmission.

The "pre decat" run was done with Millers Octane booster and so was the "Decat" run after.
the octane booster and tweaking the REVO settings made 12bhp difference alone.

366.3bhp on normal V-Power and 378.6bhp with the octane booster and REVO settings tweaked.

30k services not far off will give the millers coolant a shot me thinks, whats the crack with autotech over APR pump??

 

[Hurdy]

You got sound clips yet mate? How does sound now compare with sound before? Also, what will you be doing to resolve the fuelling issue?

The car is tucked away for Christmas at the moment, but will be making an appearance post Christmas boozing and feasting

 

[miller 666]

is that at noble motorsport on chatsworth road? If it is anychance you could give me a shout when your next there as i live literally 2 minutes up the road if that and would LOVE to see it on the RR.

Cheers

 

[Hurdy]

Yes it is Noble Motorsport in Chesterfield

I'll be there again early next year, so I can give you a bell (PM!)

 

[Knight_Rider]

Hurdy... has your downpipe still got the precat (the one right up at the start of the system)? Or have you only removed the cat shown?

 

[Al]

The Milltek does away with the pre cat mate.

 

[Hurdy]

The Milltek does away with the pre cat mate.

Just as DJH says

 

[Al]

I might just be following in your footsteps this week lad

Interested to know what you intend to do about the fuelling though and still waiting to hear back info on noise and emissions

 

[Hurdy]

I might just be following in your footsteps this week lad

Interested to know what you intend to do about the fuelling though and still waiting to hear back info on noise and emissions

Going to talk to REVO HQ and Statllers to get some logs done.

Still haven't driven the car recently as I've been over the limit most of the time

 

[Al]

Mine is booked in tomorrow to have it done

 

[robjnr]

I Might sound stupid but is a downpipe the same as a decat? I thought the 3"downpipe came off the turbo and then you'd have to change the cat seperately

 

[Blade]

I Might sound stupid but is a downpipe the same as a decat? I thought the 3"downpipe came off the turbo and then you'd have to change the cat seperately

The cat is the larger cylinder on the right after the perforated section

 

[Knight_Rider]

Just out of interest, those who have installed aftermarket full systems... did you get exhaust fumes initially in the cabin for the first few miles?

I bought a full downpipe (2 sections) which was catless and it was supposed to be a dry fit ie 2 flanges that clamped. Had it looked at because fumes were overwhelming at first. Pasted the clamped section to seal it.

Still noticed smell afterwards but it seems to have subsided to a pretty undetectable level.


Hurdy: do you find having no cat makes the exhaust fumes smell more potent, say just if the cars running and you're stood outside?

I'm getting it looked at again to check for leaks, I just wanted to know if anyone else noticed similar things.

 

[Hurdy]

Just out of interest, those who have installed aftermarket full systems... did you get exhaust fumes initially in the cabin for the first few miles?

I bought a full downpipe (2 sections) which was catless and it was supposed to be a dry fit ie 2 flanges that clamped. Had it looked at because fumes were overwhelming at first. Pasted the clamped section to seal it.

Still noticed smell afterwards but it seems to have subsided to a pretty undetectable level.


Hurdy: do you find having no cat makes the exhaust fumes smell more potent, say just if the cars running and you're stood outside?

I'm getting it looked at again to check for leaks, I just wanted to know if anyone else noticed similar things.

Yes there is initially a stronger smell, but it lessens as the engine and zorst warm up, but still slightly more of a smell than with the cat on.