Definitive De-Cat Opinion.

[MaverickUK82]

126 is losing her warranty in May and I am thinking of having her De-Catted and Re-mapped (that will be it for her - no more mods)

As far as the de-cat in concerned, is it just the prodrive sports cat (just after the turbo) that is replaced with a straight through section? I don't want to remove any more than is necessary. I still want the prodrive exhaust, etc.
- IF THIS IS THE CASE, CAN ANYONE RECOMMEND THE CORRECT PART TO PURCHASE?

Have been trawling through all the de-cat posts on here and have seen people are achieving up to 347bhp with just de-cat and remap and no other mods.
- DOES THIS SEEM FEASIBLE?

Will this combination cause any loss of driveabilty? Have seen turbo surge mentioned a few times with decat & remap
- IS THIS A POSSIBILITY?

I would really like to have the power come in earlier
- CAN THIS BE SORTED WITH A REMAP?

Thinking of taking it to Andy Forrest for a re-map, he seems to be the guy... But he's almost 400 miles away... Clive Atthowe is near me and have heard he's good.
- ANYONE HAD ANY WORK DONE BY HIM?

[dano17439]

Try Dynamix mate, he's local to you. Nice and knowledgable guy

[dynamix]

126 is losing her warranty in May and I am thinking of having her De-Catted and Re-mapped (that will be it for her - no more mods)

Good plan

As far as the de-cat in concerned, is it just the prodrive sports cat (just after the turbo) that is replaced with a straight through section? I don't want to remove any more than is necessary. I still want the prodrive exhaust, etc.
- IF THIS IS THE CASE, CAN ANYONE RECOMMEND THE CORRECT PART TO PURCHASE?

I have just negotiated a 15% discount for all of my mapping customers with Japspeed off their range of exhausts. www.japspeed.co.uk

It is just to decat downpipe that you need but you may want to change the whole system as the full 3inch stainless system is only £295 after discount and you would easily recoup that cost by selling your complete system.

Have been trawling through all the de-cat posts on here and have seen people are achieving up to 347bhp with just de-cat and remap and no other mods.
- DOES THIS SEEM FEASIBLE?

Yes - had 365bhp out of a car that I mapped with similar spec before on the rollers... 350bhp is probably more realistic on average though.

Will this combination cause any loss of driveabilty? Have seen turbo surge mentioned a few times with decat & remap
- IS THIS A POSSIBILITY?

Not if mapped properly.

I would really like to have the power come in earlier
- CAN THIS BE SORTED WITH A REMAP?

yes

Thinking of taking it to Andy Forrest for a re-map, he seems to be the guy... But he's almost 400 miles away... Clive Atthowe is near me and have heard he's good.
- ANYONE HAD ANY WORK DONE BY HIM?

There are alternatives I charge £350 for a full custom remap.

[MaverickUK82]

Lol... thanks for the reply Dynamix.

Do you do, er, 'friendly' MoT testing... lol

[MaverickUK82]

is launch control etc included in the £350?

[dynamix]

is launch control etc included in the £350?

Yes.

Re MOT friendly - I know a few

Am up in Norwich on thursday mapping - are you on scoobycity?

[MaverickUK82]

Not on Scooby City...

[MaverickUK82]

Do you do your mapping 'on-the-road' then?

[The Swede]

Excellent input, dynamix.

Could you just explain why turbo surge occurs when mapped 'wrongly' ?

[dynamix]

Excellent input, dynamix.

Could you just explain why turbo surge occurs when mapped 'wrongly' ?

essentially too much air being sucked in (or trying to be sucked in) for the turbo to push out. Can be caused by induction kits and exhaust not being matched in the mapping. Some cars are prone to do it more than others and need tweaking of the boost profile to put them right. A lot of surge can destroy turbos but most often it is just a strange noise when occuring mildly.

[dynamix]

Do you do your mapping 'on-the-road' then?

Yes mostly but I have use of a dyno up in Norwich if you wanted yours mapped on the rollers. Would need to be checked on the road afterwards to get it 100%. It does add to the cost because of roller hire.... about £100 generally.

[robcole23]

it could be me you are thinking about on scoobycity Duncan, i spoke to you about mapping my wr1 at the children in need convoy. is it really worth the agro come mot time to go the decat route for this level of tune, or is the standard prodrive cat really that restrictive?

[dynamix]

it could be me you are thinking about on scoobycity Duncan, i spoke to you about mapping my wr1 at the children in need convoy. is it really worth the agro come mot time to go the decat route for this level of tune, or is the standard prodrive cat really that restrictive?

Ah gotcha - that was fun that night

The prodrive sports cat is very good - not a lot in it power wise - maybe 10bhp

It isnt really a hassle when you know where to take it

[robcole23]

your right it was a fun night! it was my first outing with the scoobycity bunch and i hope it wont be my last.. i have also been toying with the idea if new exhausts and i managed to pick up a blitz nur spec r for not a lot more than a packet of crisps, whats your views on this exhaust with an other wise standard car and would it be suitable if i wanted to go for further mods ????

[dynamix]

Its loud

It flows well enough though - def suitable for future mods.

[ian1965]

I can vouch for duncan, he remapped my wr1 about 3 wks ago, he does it on the road, very knowledgabe guy, and my car feels and sounds so different now. ian

[dynamix]

Cheers Ian

[MaverickUK82]

Duncan,

What do you expect can be achieved with a standard WR1 retaing the original prodrive cat and exhause?

[MaverickUK82]

Exhaust*

[dynamix]

Have you had yours on the dyno so far ?

A lot of std wr1's make slightly less power than the 320bhp specced.

I would have thought around 330-340 would be along the right lines but better driveability mid range.

[MaverickUK82]

Hi again Duncan,



Here is my most recent dyno graph from December.

The red line on the graph represent a dyno run I had in august.
The blue line represents a run I had in December after fitting a performance panel air filter (green one).

What do you think?

[dynamix]

The air filter made a big difference

Clive's rollers are pretty accurate from what I have seen. Do you have the fueling/boost graphs too ?

[MaverickUK82]

The air-filter didn't make much difference in bhp. But if you check the curve after 6500rpm the power doesn't drop off as much as it did...

these are the other curves from the August dyno run... don't have the ones from december with me although I can supply them tonight.

[dynamix]

The graphs look good - think there is a little more to be had - don't there is a vast amount though but that would be a guess without monitoring the car.

[MaverickUK82]

Have you had yours on the dyno so far ?

A lot of std wr1's make slightly less power than the 320bhp specced.

I would have thought around 330-340 would be along the right lines but better driveability mid range.

Think the WR1 is specced at 315bhp and 320ps

[MaverickUK82]

Do you think it's worth having it mapped then?

Prodrive state that peak bhp should be around the 5800rpm mark,
it's nearer 6600rpm on mine.

[dynamix]

Happy to hook the laptop up to it when I am up your way if you want to meet up and give you an honest idea of whether it could do better. It is very difficult to get a real feel for the car from dyno graphs made in artificial environment.

[MaverickUK82]

That's very kind Duncan.

Sounds good!

When are you next up? I can't do this Thursday due to work and lack of 350 sheets - lol.

I doubt you'll be coming either if the weather hits like they've forecast!

I could let you have a look when you're next down and if you think anything can be achieved then I could bring it up to you for the real map...?

Does it make a difference, say, by remapping it in the sub zero temperatures when ususally usually it's going to be used when it's warm?

[dynamix]

That's very kind Duncan.

Sounds good!

When are you next up? I can't do this Thursday due to work and lack of 350 sheets - lol.

I wouldn't charge you for just looking if I was up there ...

I doubt you'll be coming either if the weather hits like they've forecast!

Hoping there will be a heat wave overnight ... bloody global warming needs to kick in soon

I could let you have a look when you're next down and if you think anything can be achieved then I could bring it up to you for the real map...?

Am up in Norwich way every other week tbh and need to get up there again before the end of the month for an MOT ... will probs be the 26th

Does it make a difference, say, by remapping it in the sub zero temperatures when ususally usually it's going to be used when it's warm?

Not really although it does mean the turbo is more inclined to want to boost so keeping it in trim in this weather is harder. The performance in the summer is unlikely to be affected as a result whereas if mapped in the summer they can sometimes overboost mildly when really cold weather sets in.

[MaverickUK82]

What time will you be up here tomorrow? (from and until... I knock off at 16:30 and am 25 minutes from Central Norwich (Bacton) - weather permitting.