cat by-pass pipes

[Bournemouth James 0]

Does cat by pass pipes make allot of difference on performance?,

I am a little confussed on this issue, cause is'nt it the law to have a cateleltic coverter?, is the cat by-pass pipe legal?, would a corrado pass an mot with a cat by-pass?

Finally, does anyone no if my corraddo has a cateletic converter fitted? mine is a h reg, and it was registered in september 1990

 

would be grateful if anyone can help me with this

 

So glad i've found this forum, theres allot of useful info on here

[VR6 0]

By-passing the cat will help performance from what i've heard (yet to do it yet myself).

 

If your car was registered in 1990 then it doesn't need a cat. Think it was about sept 92 that they started needing cats to pass the emissions tests.

 

And welcome to the forum.

[bazgreener 0]

You probably won`t notice any difference on a std car, helps if it`s modified though.

[G-Lader 0]

just got mine done today,went to RSR tyres who used a 'powerflow' s/steel piece of pipe and cut the lamba sensor holder out the old cat and welded into the new s/steel pipe so that the lamba sensor screwed right on - bit nervous at first when i saw what they were doing but they have done a great job!

Jetex for the rest of the system so its still very quiet with just a hint of throbb!

Would not say ive noticed much power gain (already got Chip n'pulley and Stg 4) but it feels as if its smother pick up - less restricted i suppose - RSR charged me £94 which is cheaper than a supersprint replacement pipe etc......hoping the emmisions will be ok for MOT but im sure they can tweak to get through if they r high

[Banana Man 0]

Would that be RSR in redhill harry as thats where I had my system made :D They did a bloody good job apart from I ve just noticed that one of the centre boxes hangers has sheared ( BUGGER ) but the system is 2 yrs old so I'll let em off. back to the point though all cars after 1990 were provisionally fitted with a catalytic converter for emmisions but the new emmision test didn't come in until Jan '93 so if you decat it then they just test your car under the old emmision test which allows 3.5%co instead of the catted test which is +-.5%co. You wont notice much difference when you decat the exhaust it only really becomes an issue if you are going for big power. When I de catted mine I think I lost a bit of low down torque but hardly noticable!

[G-Lader 0]

redhill would be the one! They are prepared to give things a go that other places would I suspect consider too much hassle. They fitted my jetex and had to cut it in loads of places to make the thing fit! Dont know how jetex claim its ready to fit! Needed loads of adjustment to stop it hitting the rear beam on bumps etc! What mods you running? any suggestions for my perf. question on the board.......

[Banana Man 0]

I bought a magnex system before I bought the powerflow and I ended up having to have it towed to RSR on a saturday morning coz the damn thing was such a bad fit. They fitted it but it kept on knocking on the rear beam I got so pissed off with it that I told them to take it off and make me up a decent system that was loud and didn't knock on anything, I ve ended up with a beast of an exhaust it cost £400 includidng the cat bypass which is a good price for a custom exhaust I think!! As for mods I'm running stg4 charger, 68mm pulley, 3.5bar FPR, isv router, and a german chip and of course the custom exhaust. I am taking it to the next level in a couple of weeks by having a front mount intercooler, 65mm pulley, flowed and ported head mated with a piper 260cam, external oil cooler and a fully customised chip should be good for an extra few horses

[G-Lader 0]

Banana - do you think a k&n,sns chip and fpr is going to make a big(ish) difference?

[Banana Man 0]

Have you had your charger ported yet?? If not then I would suggest you get the charger ported first as you will see bigger gains when you fit a 68mm pulley, FPR, chip and filter. Just a stg4 porting mated with a chip and 68mm pulley will see you nearing the 200bhp mark

[G-Lader 0]

had the jabba Stg4 with chip n'68mm pulley - suspect i will change the chip(to SNS) and get the fpr that they recommend and either a kn replacement filter or a cone with heat shield (saw these @ jabba and Dubcharged thinks these r the way to go next)

suspect there is not much else i can do without internal engine mods - cam etc

[Banana Man 0]

I use the JR cone filter that jabba use and have mounted it in the inner wing out of the way of all that horrible engine heat ( you have to takethe Carbon canister out for this ) Even with the heat shie;d you aren't getting anymore airflow as the only air getting to the filter is the air coming between the gaps in the headlights so you aren't really benefitting much by fittng the heatshield imho. The isv mod is well worthwhile doing and it is a very cheap mod to do, first of all you can cap of the boost return pipe on the charger or you can drop the rad a couple of inches and run a second ram filter and run the isv back into the intercooler pipe between the throttle body and co potentiometer so any leaked boost from your ISV wont be wasted and then just run a breather filter on the top of the rocker cover.

[G-Lader 0]

lost me there im afraid,isv and all that has confused the hell outta me!

[Banana Man 0]

ISV Idle Stabilisation valve its the silver tube looking thing that sits on the back of the rocker cover one pipe goes into the inlet manifold the other feeds into the boost return pipe on the charger.

[Dubcharged 0]

Putting the filter in the wing is the best way, just make sure it wont get damaged by debris or excessive water.

 

Alternative to rerouting the ISV, you can just stick a breather filter on it!

 

Banana: I'm glad there's someone else out there who has realised the benefits of removing the bypass pipe! :D

[W3RKD 0]

the biggest benifit in removing the bypass pipe is for the lack of heat taken back to the charger! imho it is a great mod IF you can put up with the extra noise in the car... oh well i spose we wouldnt have a g60 if we wanted a quiet and boring ride ehh :lol:

[W3RKD 0]

here's mine previouslly.....

[W3RKD 0]

mind you most of this gear is now under banana's bonnett as we are develping lots of new bits @ the moment!! :shock:

[g60pops 0]

Darren what make are your ht leads?

 

cheers

[W3RKD 0]

they are nology leads come in various colours now :mad: if you are intrested in a set contact us mate...