de Catt Y power results

[ClassiChimi]

As above really, I've still got my original Catted Y in place which I like for sound deadening and low emissions but I can't help but think I might be missing something and the car may posses more BHP AND TORQUE with a de cat Y such as Clive's.

I'm running an after market Ecu (Mbe) so realise I'll need a re map etc

My car mapped last year when put on the Mbe system produced around
300bhp
350 ft lb torque on Dom's rolling road.
These figures are the calculation back to the flywheel and could be as much as 5% high in reality

My question is
I'm assuming the car will generate more BHP but is there a risk I'll actually loose Torque by putting a straight through Y piece on, (less back pressure)

Has anyone got Dyno figures for a Catted to de Catted car.

I'm very happy with the power output and general running of my car but if I could remove some more heat from the engine bay and free up a few more horses as well as hold on to my torque curve Id be interested in doing it.

Am I wrong in worrying about a loss of torque with a more free flowing exhaust?

[QBee]

Unless I am very much mistaken, I am not sure you will need a remap. The fuelling is taken care of by the lambda sensors. The Y piece comes with a multi-resistor thingy to fit in case you want to run without lambdas, but so long as you leave the lambdas in (and why wouldn't you?) then you use the standard catted resistor position.

Alun, if you have a couple of long luggage straps and a day to spare, get yourself over to mine on the next sunny day we are both not working, and we can take the Clive Y off my car, fit it to your car, and you can spend the rest of the day seeing what you think of the way it drives and the sound it makes.

If you are smart and arrange it ahead of time, you can divert via Jools (M1 J28, adds about 45 miles) on the way to me for a quick RR run, then take it over there again after fitting for another RR run and his views on your fuelling etc. Or pop into Dom ditto.

As long as I have the Y back on my car in a few days.....

[phazed]

I gained as much as 20 bhp when I removed my cat from the 4.6 car.

I am sure torque was increased as well although I can't remember precisely but I do remember that the car was very noticeably much more sprightly all round.

[QBee]

phazed said:

I gained as much as 20 bhp when I removed my cat from the 4.6 car.

I am sure torque was increased as well although I can't remember precisely but I do remember that the car was very noticeably much more sprightly all round.

I did too.....

[QBee]

PS don't worry about the lack of garage facilities at mine - Nigel's garage down the road has all we need, four post lift etc, with Nigel and Darren on hand to sort what we can't.
Did I mention he used to do 9s down the pod back in the day in his large block Vauxhall Victor?



His Humber Hawk will have you wetting yourself when you open the bonnet too. And he can talk autobks with the best of them. Last time I took Erin Dawes down there to collect a car there was a blue Cobra with white stripes in for an MOT....

[macdeb]

[shame on me for encouraging hi-jack but fook], Victor with welded up rear doors looks well cool.
as you were.

[ChilliWhizz]

Alun, here's a before and after... Note the difference in the torque curve which is very noticeable at around 2600 rpm.... peak torque and bhp (at the wheels) went up by around 18 each, although the rpm that the increased figures peaked at were pretty much the same as before the decat... The precats were already out so the only modification difference was original Y out and a Clive F Y in... It must have unleashed what was waiting to get out, and the difference on the road was astonishing for what was about 5 hours work (silencer de-sleeved and put back to original)

Chilli

Note: you may have seen this dyno print out before



Just to add, the engine also spun up properly quick... and it was quick before

Edited by ChilliWhizz on Saturday 30th July 11:39

[ClassiChimi]

Thank you Richard That's one hell of an engine, I've never looked that closely.
This is the graph I've been asking for.
I'm genuinely excited at the way your engine performs,,

It seems to show the more base engine work done the more the gains will be at each other mod stage.

Your showing huge gains when you think about it,, just a bit of old Pipe????!!!!
It's a thing of utter beauty is Clive's Y and it's firmly in my sights now.

I'm so impressed with the power out put of mine using the big old heavy Catt that seeing what you've done there,,,
It's a no brainier.

You know I dream of your inlet don't you hand made, it's just the best, it can't be doing you any harm either by the look of those figures,, 360hp,,, I'm giggling, I see what your getting at now, you often rave, as I do but fk me Richard that's a beast

I have seen your graph but somehow didn't really take in the reality of it, maybe driving mine for awhile has helped put your car into perspective. Bloody Aider mate,

Put that engine in your MG for 6 months,, outrageous.

Edited by ClassiChimi on Saturday 30th July 12:04

[ChilliWhizz]

ClassiChimi said:

Thank you Richard That's one hell of an engine, I've never looked that closely.
This is the graph I've been asking for.
I'm genuinely excited at the way your engine performs,,

It seems to show the more base engine work done the more the gains will be at each other mod stage.

Your showing huge gains when you think about it,, just a bit of old Pipe????!!!!
It's a thing of utter beauty is Clive's Y and it's firmly in my sights now.

I'm so impressed with the power out put of mine using the big old heavy Catt that seeing what you've done there,,,
It's a no brainier.

You know I dream of your inlet don't you hand made, it's just the best, it can't be doing you any harm either by the look of those figures,, 360hp,,, I'm giggling, I see what your getting at now, you often rave, as I do but fk me Richard that's a beast

I have seen your graph but somehow didn't really take in the reality of it, maybe driving mine for awhile has helped put your car into perspective. Bloody Aider mate,

Put that engine in your MG for 6 months,, outrageous.

Edited by ClassiChimi on Saturday 30th July 12:04

Cheers Alun, it's a pussycat to drive too Apart from the emissions issue I see no downsides to Clive's Y at all Oh, and did I mention the noise?

Edited by ChilliWhizz on Sunday 31st July 09:41

[davelittlewood]

So what does happen at MOT time??

[QBee]

Not got a scoobie - my TVR guy puts it in for MOT and it comes back with a new stutiftikit.

I have actually kept the original catted Y in case i need it, and lend it out to less fortunate mortals with broken cats at MOT time

[bobfather]

davelittlewood said:

So what does happen at MOT time??

You find a friendly MOT station, loads of them will do it. Decating isn't just a TVR thing, Lotus, Caterham, Audi, Porsche and all the MaxPower boys in the loud shopping cars go decat

[ChilliWhizz]

QBee said:

Not got a scoobie - my TVR guy puts it in for MOT and it comes back with a new stutiftikit.

I have actually kept the original catted Y in case i need it, and lend it out to less fortunate mortals with broken cats at MOT time

Ditto.....

[fatboychim]

QBee said:

Not got a scoobie - my TVR guy puts it in for MOT and it comes back with a new stutiftikit.

I have actually kept the original catted Y in case i need it, and lend it out to less fortunate mortals with broken cats at MOT time

Now you've paid the ransom and got it back from the Essex gangsters.

[phazed]

fatboychim said:

Now you've paid the ransom and got it back from the Essex gangsters.

Hey hey, where have you been?

[sheel]

Mine seems to have a magic 10mins it goes in as a tvr Sits in the bay and transforms itself into a fiesta or something similar and then reverts back to a tvr with te relevant paperwork.....amazing cars these!!!
Rich

[Matthew Poxon]

Not sure how but mine passes the test with the the Clive Y piece.

[fatboychim]

phazed said:

Hey hey, where have you been?

I still pop in from time to time, been to busy for tivving the last year or so and done practically nothing with the car but hope to change that soon.
Back on topic, I have no MOT problems with the Clive F

[StarmistBlue400]

Matthew Poxon said:

Not sure how but mine passes the test with the the Clive Y piece.

Mine did when the Pre Cats were still in. With the full De Cat and sleeved it still recorded surprisingly good emissions.

Still a fail but shows what lean engines they are.