I had a My99/00 for several years with an open kneck decat downpipe (retaining the centre cat) and a Tek 2 map. Boast was 16.5 psi (iirc the standard ECU boast was around 13psi) with plenty of torque. I've just changed it for a standard 2001 bug eye. Will changing the downpipe and leaving the centre cat have the same effect as it did on the classic? And would a remap make much difference (the 2001 seems to boast at 16.5psi already but the throttle needs to be wide open)? Anyone help, please?
Graham

 

Yes and yes. There is an additional cat in the uppipe as well so you should also consider changing that

btw, there is only a cat in the downpipe on classics.

 

Thanks. I believe there is a centre cat on the classic - mine passed its mot several times with the decat downpipe.

I'm assuming the up-pipe cat doesn't affect the performance too much because it comes before the turbo - is that a wrong assumption?

Is there an 'off the shelf' cat for the bug eye like the Tek 1,2,3 for the MY99/00?

Sorry 'bout all the questions it's a new learning curve.

Graham

 

You must have been very lucky then...definitely no second cat on classics

Yup, the cat in the uppipe is restrictive and therefore costs you both power and response. If you do replace the uppipe don't buy a cheap one with a flex-joint, they are prone to blowing.

A MY01 can be remapped in the same way as a v5\6, in fact it may even be cheaper as open source software is available so no expensive Ecutek license require.