56 replies to this topic

[griffo]

[about 500 millivolts ] Apologies. This should read ...about 50 mv...(not 500 mv). Griffo

[P11 COV]

Cheers mate, looks like my weekend will be spent under the car again!!!

Gonna have a go myself, seems simple enough.

Will let u know the results.

Mike.

Mike

Do let us know how you get on. It's been something I've been considering doing, due to it seeming to be the cheapest and easiest way of improving performance.

I have some basic mechanical skills but this is perhaps a little more than I would normally attempt, (especially on my first brand new car!) so an honest idea of how easy the job would be to someone like me would be useful.

Paul

[Ricky2772]

it's not too bad of a job, really. car need t be somewhat lifted though. I use 2 regular winding lifters (audi source) since the hydro. jacks do not fit anymore under my lowered beast! I then somewhat secure it with wood logs beneath, just in case.. 16 mm wrench from below for the 3-bolt pre-kat side. the trickiest part was disconnecting the lambda sensor, reeeally tight! pre-soak with ample WD40 is a must. about the MIL eliminator: I tried to figure out the voltage of the resistor, one was something like 10000 Mohm (from the colored rings) but did not have the time/energy to ask around about the other green capacitor/resistor ... it requires cutting through the shrink-wrap, that can be easily replaced afterward..... Griffo, if you find out, please let us know, so I can avoid ordering another one in case my fix does not work..... ....not that I give much of a rat's ass of the MIL light, but....it's kind annoying to have it lit in your pupils...

[R3D VX]

Right, have spent quite a while under the beastie today, getting the panels off was piece of p*ss, then came the bolts before the pre-cat and the bolts after the second cat, How the hell do you undo them when they seem to resemble an early Alfa's wheel arches!!!, even with every socket and spanner i own not fitting properly. I tried all the metric sizes (13mm was closest) and imperial (1/2 nearly fitting). The sods were so crumbly i am worried that one may snap which would bugger things up considerably. I have had to admit defeat and my local Hi-Q have said they will take up the challenge! While down there i did notice that the exhaust had stamped on the underside "Track Use Only" am i buggered come MOT time anyway? Any advice people?? Cheers Mike.

[rasputin]

FOR THE LAST TIME A SPORTS EXSHAUST WILL PASS AN MOT!!! soz i had to shout

[Ricky2772]

How the hell do you undo them when they seem to resemble an early Alfa's wheel arches!!!, even with every socket and spanner i own not fitting properly. I tried all the metric sizes (13mm was closest) and imperial (1/2 nearly fitting).

did you pre-soak'em with WD-40?

those after the kat (1/2 size I think)are a real bitch, after removing'em I replaced'em with new steel ones. the thread of one was totally eaten away, like they installed the corresponding nut wrong.....

otoh, the 3 by the pre-kat (16mm)were real easy with the big wrench.

[P11 COV]

While down there i did notice that the exhaust had stamped on the underside "Track Use Only" am i buggered come MOT time anyway?

Any advice people??

Cheers

Mike.

They have to say that beacause the noise level produced is illegal.

Just don't floor it in front of a policeman (or near my house like the locall nova brigade do) and you'll be okay.

[R3D VX]

That's ok then, Will give u an update when i get the pre cat out. If the Management light does come on after removal of just the pre cat could i splice the first lambda sensors wiring in with the second so it takes it's reading after a cat? I'm hoping for no lights, but if i do have a problem then the second cat is coming out aswell. I will sort the light come MOT time (over a year away yet) Keep the good ideas comin! mike.

[Ricky2772]

let's set this straight: removing the pre-kat will change absolutely NOTHING emission/MIL light-wise. only gains, no troubles! removing the kat will make the MIL light on, and the emission will be screwed. so you have to reinstall it for MOT. if the MIL bypass trick somehow does not work, by disconnecting the battery the MIL light will stay off for a few days (2/300 km), assuming it could be a temporary change due to fuel/air differences, then will light up again. what I do now before taking the car to Opel is disconnect the battery just before, so they won't come up to me asking petty questions....

[griffo]

[QUOTE]Griffo,
if you find out, please let us know, so I can avoid ordering another one in case my fix does not work.....
....not that I give much of a rat's ass of the MIL light, but....it's kind annoying to have it lit in your pupils...

Yeh. no problem. My expensive (20 dollar)MIL eliminator has arrived from www.zx2racing.com (an outfit in California) so I'll be fitting that. I'll only try to make up my own resistor if that fails to keep the light off.

I must endorse your comments to our friend who is removing his pre-cat -- absolutely no problems with the MIL light (or MOT) with that and only good gains. Be sure to use a powerful vacuum cleaner to suck out ALL the dust and bits and pieces that will be caused when you grind/ drill / chisel out the bloody thing since, if you're keeping the main cat, you dont want it getting all clogged up with detritus.

cuddles

Griffo

[P11 COV]

The sods were so crumbly i am worried that one may snap which would bugger things up considerably. I have had to admit defeat and my local Hi-Q have said they will take up the challenge!

Where is that Mike?

I might take mine there after they've practised on yours!!

[R3D VX]

It's on the lower side of Fenny Stratford going out towards the A5 and the little chef. I am gonna try to get it done today (Monday) Will let u know. Must go, Mock sats exams to prepare!!!!!

[R3D VX]

Done it!!! Took about 3 hours labour all in, The car is slightly louder, pops a little more on the overrun, and revs much better, i think the in gear times have really tumbled!! What a sod to remove though!!! and it is no surprise that it frees things up, i couldn't believe my eyes when i saw the mesh!! How tight were the holes!!! Anyway job done, Now it just needs booking in at Regal for the stage 1 tune. Paul, if you fancy a blast let me know, you know where i live!!! i'll be in after 5:30ish every day this week, but not around at the weekend! Money well spent, Mike. 01908 630770

[P11 COV]

Cheers Mike Could I pop round shortly after 5.30 on Weds? How much did they charge?

[BogBrush]

This sounds like an interesting Mod. How much did they charge for this job? Preferably i'd like to keep the original pre cat and play about with a spare one. Can these be bought from somewhere at a reasonable price? Also, if this is such an easy increase in power, why doesn't regal offer it as a mod? Regards, Colin

Edited by BogBrush, 17 March 2003 - 11:27 PM.

[R3D VX]

They will charge £40 an hour labour!! the job could probably be done in 2hrs now they have practised on my car. It all depends on the condition of the bolts etc.. As for getting another pre-cat to use i do know that normal cats are bloody expensive, i don't know about the pre-cat. You might want to message Turboman, he has access to the VX parts database. Pass on the Regal question, I would guess they might have a new bypass pipe but again it will probably cost a pretty penny.# Regards, Mike.

[garyk220]

Also, if this is such an easy increase in power, why doesn't regal offer it as a mod?

It would possibly undermine sales of their manifold and sports cat?

Mike, is the pre-cat in the manifold or the catalyst downpipe?

Edited by garyk220, 18 March 2003 - 03:36 PM.

[Ricky2772]

Mike, is the pre-cat in the manifold or the catalyst downpipe?

look at the pics in the prev. posts...
it's right after the manifold, at the connection with the cat pipe.

[BogBrush]

Hmmm I might have a go at this anyway. If it doesn't affect the car then it seems simple enough. That is if I can get the car up onto my ramps. I've got a feeling the front will scrape along the floor when I'm reversing up them?

[VEX]

That looks like a visit to Hi-Q for me in April then. I know exactly where they are so I'll give them a ring and get it in there one weekend. Cool. Thanks R3D VX. Enhanced MK VX's here we come. Cw.