9a decat - practicality, functionality, driveability.

[Bazmcc 0]

I just put a 4 branch manifold/decat onto my 1994 9a.

 

I've noticed for a start it's louder but it's not too bad. But I have a few questions.

 

How much power is it actually likely to add (I have a catback milltek behind it)?

 

Will my fuel consumption suffer?

 

Will I need to put a CAT in for MOT?

 

Can I fit a CAT between the 4 branch and the first silencer?

 

Do I just leave the O2 sensor out of the equation completely?

 

Will it run ok without a sensor plugged in?

 

Will I fail emissions?

 

Sorry for the barage of questions but this is the best place to ask.

[Critical_Mass 10]

Yes you probably will fail the MOT due to emissions. If its registered after 92 you'll need to put a CAT on.

 

As for the power gains, they will be minimal if anything. The Decat should have a hole to put the 02 sensor in, you cant just delete the 02 sensor.

[moneypit23 0]

I noticed a much better throttle response after having a powerflow (decat) fitted, never had a power increase confirmed though. It did need the cat put back in for the MOT and that became an issue but i think that was due to the shoddy powerflow workmanship.

[Big'G' 0]

I'm planning a 4 branch for my '94 Valver, where did you get your Baz, and was it pricey?

[Bazmcc 0]

Got it from a forum member on here. I think I gave him £140 delivered. It was brand new and still in the wrapping. Very well made piece of kit too.

[Bazmcc 0]

I think I've just developed a bloody louding ticking noise.

 

It goes away when i hold it at 1500 rpm. It only seems to tick loud when I'm accelerating when it's out on the road. Otherwise it's perfectly smooth and quiet.

 

Can anyone tell if I have a busted lifter just by the sound? or is it something to do with the 4 branch.

 

Click below for the video.

 

[aide 0]

my 4 branch was noisier than normal, but nothing like that my man, more of an echo'y metal rattle.

 

i'd guess lifter from that vid.

[Bazmcc 0]

Would there be any reason it only does it at idle and when I'm accellerating?

[aide 0]

oil supply perhaps, as I understand it lifters need a certain amount of oil before they begin to 'float' maybe supply only becomes sufficient for a busted lifter once over certain revs.

[Bazmcc 0]

I understand. I'd have thought the spring would have made them all contact the cam the same. but I suppose if the lifter is sunk in the center then that contact patch will change. I have a spare set of KR cams in the garage so I think it's time for that timing belt and cam change.