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will i need to run a cat after engine install?
daniel mason - 20/1/13 at 10:26 AM

as some of you may know im in the process of converting a 1995 1.4 k series to a 2007 hayabusa in a 1995 M reg caterham.
will i need to run a cat? or can i get away without?
amongst all the second hand items i bought are 2 x 2-1 exhaust collector but one of them has a built in race cat,which when you look through it,looks like its just packed with some wire mesh. and one is straight through! i would ideally like to sell one of these but not sure which one? cheers

Ben_Copeland - 20/1/13 at 10:34 AM

Keep the cat for MOT just incase, use the straight through the rest of the year

ashg - 20/1/13 at 10:38 AM

was it built with a cat? if it was you need to keep it, if not sling it.

daniel mason - 20/1/13 at 10:42 AM

dont think it had a cat unless it was built into silencer? and i only had it a few months before i ripped the engine out! so never mot'd it

deezee - 20/1/13 at 10:54 AM

As the car is already registered, its not the engine, but what kind of emissions test the car has to go through for its MOT. So if the car previously needed a cat test before, it will need one after the engine change.

bigfoot4616 - 20/1/13 at 11:35 AM

is it not possible to have a map for the power commander that will get it through the cat test without a cat?
a good friendly tester would let you tweak it while he tested it.

daniel mason - 20/1/13 at 12:41 PM

am running mbe ecu so maybe can get 2 maps. im gonna get sbd to send me some maps

adithorp - 20/1/13 at 05:57 PM

If the car was SVA/IVA'd without then it doesn't need a cat' after and visa-versa... whatever engine you put in. It should have the emission requirements on the v5 (although it wouldn't be unknown for DVLA to have missed it out). If it's on a Q plate then it doesn't/shouldn't be tested for emissions anyway at MOT, just visable smoke.

If it was a pre-August 95 engine then it should be the pre-cat' test. The V5 will show CO <3.5% @ idle and HC <1200ppm.
If the V5 lists CO <0.5% HC <200ppm and Lambda 0.97-1.03 at fast idle and <0.5% CO @ idle, then it needs a cat'. No amount of tuning will achieve that without a cat... unless you get a VERY helpful tester.

daniel mason - 20/1/13 at 06:16 PM

got th v5 in front of me and there is no numbers at all after the emissions info in section V?

adithorp - 20/1/13 at 09:35 PM

quote:
Originally posted by daniel mason
got th v5 in front of me and there is no numbers at all after the emissions info in section V?


Not sure which section is which. Think you're talking about the bit for CO g/km for tin top emission (used for tax class on newer cars). The MOT emission info for a kit is in the notes section (front page I think) if DVLA have entered. It's not there for older cars; Don't know when they started putting it on.