Modify your Pre-CAT

[RichardK]

Andy, also have a read of the first page of this thread - the Doc and others relate their experiences.

Richard

[max and andy]

Reading the early posts it sounds like I'm going to snap some studs. Would your average exhaust stockist carry the studs or am i going to have to order if one snaps? Will i be able to get Piper to send new ones with the PCE? Also reading early posts it suggests porting at the same time is advisable. Is this what most have done? Ive also read fitting a sports cat stops boost creep? Sorry i won't ask anymore tonight. Andy

[Enright]

Reading the early posts it sounds like I'm going to snap some studs.

Don't attempt it - fitting an exhaust without decent access (i.e. proper overhead hydraulic lift) and a gas-axe to deal with the roasted solid rusted fasteners simply isn't worth it. Find an exhaust fitting centre that will do the job - it will take them less than an hour and should cost about £40 - it would take you half a day, you'd probably break stuff and it's just no fun at all.

Would your average exhaust stockist carry the studs or am i going to have to order if one snaps?

They should do.

Will i be able to get Piper to send new ones with the PCE?

No I don't think they supply those.

Also reading early posts it suggests porting at the same time is advisable. Is this what most have done?

I'd wait to see if you actually get boost creep afterwards. Some do, some don't.

Ive also read fitting a sports cat stops boost creep?

It may be insurance against getting creep (by having a restriction in there), but it's no guarantee.

Sorry i won't ask anymore tonight. Andy

PHEW!

[max and andy]

Thanks Neil. I wont try myself its just the Kwickfit i went to today s..t himself when he had a look at the pre cat today. I'm going to order the Piper and PCE tomorrow. I was going to today. Until i read a thread about fitting a sports cat and not having boost creep problems if you fit one. It sounded cheaper paying for the sports cat rather than paying for it to be ported. Andy

[Elanlover]

Thanks Neil. I wont try myself its just the Kwickfit i went to today s..t himself when he had a look at the pre cat today. I'm going to order the Piper and PCE tomorrow. I was going to today. Until i read a thread about fitting a sports cat and not having boost creep problems if you fit one. It sounded cheaper paying for the sports cat rather than paying for it to be ported. Andy

If you can ditch the precat and stick with the main cat do it. It greatly decreases turbo lag. Now, if you can't source a "stiffy" or PCE to delete the precat you could look into having the shop remove the turbo exhaust manifold, slice off the mating plate at the bottom of it where it meets the precat and have them graft some pipe directly to it and finish the run.

[max and andy]

The main cat has already been removed. I'm ordering the PCE tomorrow. I think the pre cats buggered anyway. It was the boost creep and having to port the wastegate. Id read a sports cat would put that right. To avoid the porting but it might not. Or i may not get creep at all. I think i have decided to try the car with no cats. Andy

[rip]

You may get close to the emissions limit at MOT time.
Having said that, Geoff's S2 has got through several MOTs with a Peco & no cats so hopefully you'll be ok too.

[max and andy]

MOT time is now. We hoped to get it in before we changed the exhaust. But now the back box has popped that's out the window. We are still having second thoughts and didn't quite have the bottle to order today. Does the cost go up any if you buy the sports cat separate? Andy

[dapinky]

Does the cost go up any if you buy the sports cat separate? Andy

The unit is the same price, but (presumably) there will be a postage issue with 2 seperate orders, as Piper use a courier, not Royal Mail, so there will be 2 distinct trips.

[max and andy]

Just thinking if it failed the MOT we could pop a sports cat in at a later date. There is also a list of to do's before the MOT. Is the base timing worth looking at? Andy

[Enright]

Is the base timing worth looking at?

Always.

[woody]

You may get close to the emissions limit at MOT time.
Having said that, Geoff's S2 has got through several MOTs with a Peco & no cats so hopefully you'll be ok too.

Having just fitted the PECO, and after removing both cats,my S2 has just passed the MOT, and was well within the limit.
Cheers,
Woody

[HJ2]

can you specify those Limits and the measurements of your particular Elan? I wonder if the limits differ much from the Dutch.....
CO level has my special attention at the moment.

For my information: I have an S2 with a mountain chip, PECO, no cat and no pre cat. Is or can my Elan be closed loop?

[max and andy]

Nice one Woody that makes us feel a bit better. I think all S2s are closed loop if i remember right. I think it was Enright who went through it with us. I did get it at the time but Ive forgotten so can't help much other then pointing you his way. Andy

[woody]

Hj2,
From MOT test.
Fast Idle Speed:-
RPM-Min Limit 2500,Max Limit 3000,Actual Value 2819-Pass
CO-% vol - Max Limit 0.200,Actual Value 0.070 - Pass
HC-ppm value - Max Limit 200,Actual Value 18 -Pass
Lambda - Min Limit 0.970,Max Limit 1.030,Actual Value 1.010 - Pass

Natural Idle Test :-
RPM - Min Limit 450,Max Limit 1500,Actual Value 957 - Pass
CO-% vol - Max Limit 0.300,Actual Value 0.012 - Pass.

Hope this helps.
Cheers,
Woody

[HJ2]

Thanks Woody, this is just the info i wanted!
Now on to a comparison with the Dutch law

BTW: Lambda was exiting critical!
I guess before MOT: Replace air filter, clean sparky's, set base timing and idle... Anything else one can do to have a better chance passing MOT?

Cheers!
Henk-Jan

[DeanG]

The old pre-cat is out and the new better flowing hollowed out pre-cat is in. I did a bit of work with a die grinder to smooth things out a bit in the casting.

Hosing down the old nuts and bolts with penetrating oil was the smartest thing I did with this project. Several applications were required. Some of the bolts were a bear to get off. On the other hand one of the heat shield bolts took a solid half hour to get it threaded. I probably have 10 - 15 hours into this project so far. I would never make it as a mechanic, I would starve.

I just have to replace a bit of heat shield under the main cat and put in the down pipe. I should finish that up tomorrow, July 4th Independence day. Then a half hour of moving cars and trailers around and I can go for a ride!

It will be interesting as the rest of the exhaust is standard. I haven't noticed much difference in the feel of the car since I had the put a blow off valve and the mountain chip installed. The blow off valve was the third non-hidden modification to the car (the first and second were a Momo shift knob and an alarm speaker by a prior owner over 10 years ago.) I still don't like the look of the mods when I open the hood.

I decided to go with a hollowed out pre-cat rather than the PCE I bought in order to keep it looking stock up there. The PCE will be going up for sale on LEC before it goes to eBay.

[DeanG]

A big difference in how the car drives. Too many police out to have much fun due to Independence day, odd how that works. Boost needle starts to waver with least bit of throttle.

The PCE will be up for sale this coming week.

[superbad]

So in your experience the stock hollowed out precat is better than a PCE? (Or am I misunderstanding what you wrote?) Did you buy a PCE and not use it?

[tweetdriver63]

So in your experience the stock hollowed out precat is better than a PCE? (Or am I misunderstanding what you wrote?) Did you buy a PCE and not use it?

decided to go with a hollowed out pre-cat rather than the PCE I bought in order to keep it looking stock up there.

Personally, I plan to hollow out my pre-cat someday. I'm going to do that instead of the PCE, just because it's cheaper.