Piper exhaust/pce

[Geordie]

Hi all
Got chance of piper 2-25” exhaust with single silencer,my question is should I purchase the PCE or Downpipe as well ? And if so depending on which one ,would I need to enlarge wastegate or remap her,she’s a 91 m100 se and she’s already chipped ,no intention of tracking her ,but do a few driving tours with her and I have a need for speed
Cheers in advance ,

[Fredjohn]

Go for it!
But do it in stages. You have already remapped with the chip (Everest?). The heavy cast iron pipe after the turbo contains the initial cat, but ONLY on the S2. On the SE it is empty. Fitting the lighter downpipe to replace it will follow Colin's mantra of added lightness.

Porting the wastegate will only be necessary if you get overboost. This is less likely with the 2.25 exhaust than the 2.5. Wait to see if it happens once you have fitted the new exhaust.

I have a 2.25 (Powerflow) exhaust. No overboost. However, it was all fitted before I bought the car, so I've no idea if the wastegate was ported!

However, if you want it done all mostly at once to minimise down time and removal/replacement, get the exhaust and the lighter downpipe and fit them. Leave potential porting until you know whether or not you need it.

Good luck.

[Geordie]

Hi
cheers for reply I’ve only heard of piper or peco (pnm) before ,there are some companies offering a custom made system but not sure about that ,of the shelf seems a more sensible way to go ,but maybe I’m being a bit conservative,contacted a local power flow dealer ,just waiting for reply and the dreaded prices

[LeedsMike]

I am just about to upgrade my s2 stock system to a piper 2.25 sports cat system.

I already have the Everest upgrade

I have a 2nd turbo that has had a fresh rebuild and is ported to 20mm

I purchased the 2.25 pce but have since thought that the 2.5 down pipe combined with a 2.25 cat system may be a better option.

Question- is my working assumption that with the pce I will be ok for emissions and creep?

Question - will the 2.5 down pipe be a better setup or might it give me other issues?

Appreciate anyone for advice! Thanks!

[dapinky]

I can't say that it will definitely pass the UK emissions test, as I have only ever had to worry about SE numbers....

.... I have the same system on mine (2 1/4" Piper, with PCE, 20mm ported, Everest chip)..... it easily passes the SE requirements, but would be too high for an S2.

I have no cat fitted (as I don't need one) but would expect you to need something to get the numbers low enough.

I didn't want/need a 2 1/2" downpipe as the gasflow is such that it would offer very little difference to the 2 1/4" system unless you also change the turbo/injectors/MAP sensor etc to push the power output beyond what you are looking at.

Basically, the 2 1/2" only offers advantages once you go beyond what the standard 'mechanical' bits can provide anyway.

[LeedsMike]

Brilliant, thanks Dave!

I will report back on progress.

[MPx]

As always, great advice from Pinky.

I've got the piper 2.25 with PCE and sports cat with a switcher chip and 20/21mm port. Never had a creep issue. There have been years where passing the MoT emissions has been problematical. If base timing (and tuning) is spot on it will pass the test. I've had least issues with my switcher on prog 1 (standard S2 map) but sometimes I forget and leave it on 6 (Everest) which has coincided with the difficult years although I'm convinced it was base timing more than the chip causing the trouble. Quite apart from other potential issues, the 2.5 is just too loud/boomy for me and spoils any drive longer than a few minutes.

[Tuga2112]

i've ran a 2.25 system not ported (AFAIK) for many years and probably more than 20k miles without everest chip (the scenario most noted for creep issues) with 1 instance of creep... which was the wastegate being stuck.

i have updated to everest with one of RonR's test chips and never had the issue with that setup either (althought i done a lot less miles by comparison )

my point is. your not guaranteed to get creep issues even under the conditions that people report more often.

just keep in mind that you only see posts in the forum when
1 - people have problems
2 - people want to 'brag' about what they achieved

[johnj]

Hi

MY car passed it's MOT but it has a rattle from the exhaust that I asked the garage to have a look at. I thought it sounded like a heat shield but was told it the cat breaking down. I was given an estimate to change the cat but I think it would be a good excuse to fit a complete new system. I am thinking of fitting a 2.25inch Piper system with PCE. The car is an S2 with Everest chip and K & N air filter I am wondering if anyone who has this system can say how it affects the MOT hydrocarbons etc, or should I keep the pre car?

[MPx]

Ha! Very similar to my set up as mentioned above. I think it depends a bit on your relationship with the MoT tester. Its likely to be marginal with the Everest - but can genuinely pass if timing/tuning are spot on. Alternatively you could do a temp fit of an extra cat for each MoT Test - a right fag but does the job. The benefit of no PC is breathability of the engine - something you obviously value given the investment in larger exhaust and K&N. Whether the risk of tricky tests are worth it in this case is a decision only you can make. Clearly I do think its worth it. Best of luck.

[dapinky]

I have 2 answers - 1 that you asked for, and one that you didn't (but is relevant).

The unsolicited bit is that as an S2 (after Aug 1993) the car is required to meet the lower levels of emissions..... this was done originally by Lotus fitting a Cat/pre-cat to the car.

Now, if the car can meet the requirements without those present, everything *should* be good... except they then changed the rules to say that if a car had a Cat from new, it MUST be present on the car for it to pass an MOT. There is nowt in the rules about a "Pre-cat"...... is it a cat, or isn't it a cat??? Who knows...... but I'd argue that it isn't for the purpose of being "present" - but if it helps to pass the emissions, it may be considered beneficial.

I have completely ignored the fact that there is an actual exemption for the lower numbers if the engine can be shown to be from before Aug 93, as it is a somewhat grey area which I have never had to research, but I know that other S2 owners have experience of the laws ( Smiffy!).

You don't mention if you are looking at the Piper system with or without a "sportscat" as they call it - which is (legally) fine on an Elan as the Cat doesn't need to be 'Type Approved' for a car registered before 2001, so anything that works is okay.

My car is not an S2 - but it is an SE with closed-loop, so as far as emissions go, it should be the same - except for the cat/pre-cat which I don't have...... I have a Piper 2 1/4" with PCE, and a single silencer.

At the MOT test this year it had 0.36 CO, and 41ppm HC..... which would be okay on HC, and slightly high on CO for a car that needs to meet the lower requirements (0.3 at idle).

I run an Everest chip (which should make no difference at all at idle - but may do for a 'fast idle' S2 test).

All this to say, there is no reason why an otherwise-good engine with the system you talk about will not pass an MOT, if you have a sportscat, and if you have a friendly tester, then even the sportscat may not be an absolute necessity.

[Tuga2112]

and theres always that point that the tester "must see a cat" does not mean the outer shell that looks like a cat actually has any mesh inside...
as with all things, having a friendly tester is far more valuable than actually knowing the law.

[Saltire]

My car is not an S2 - but it is an SE with closed-loop, so as far as emissions go, it should be the same - except for the cat/pre-cat which I don't have...... I have a Piper 2 1/4" with PCE, and a single silencer.

At the MOT test this year it had 0.36 CO, and 41ppm HC..... which would be okay on HC, and slightly high on CO for a car that needs to meet the lower requirements (0.3 at idle).

For comparison, my bog standard S2 (no Everest) had its MoT last week, and registered 0.168 CO and 12ppm HC

[johnj]

Thanks for all the replies.

The system I am looking at is the sports cat one so all seems good. I also believe the car to have been build in July '93. Happy days

[bxs]

I have just replaced my stock 2-cat exhaust system with a Cat-less Piper 2.25 with single oval muffler. No ECU chip has been installed. The engine/turbo response is very noticeable with the new Piper. 1st through 3rd is now super responsive with revs climbing VERY quickly. The exhaust sound is a tad louder but IMO it's nice to hear.

Boost gauge will blip up momentarily to around 0.6-0.7 under hard acceleration. Not seeing any 'boost creep' so far.

The sliding fit of the Piper pipe pieces did mean having to install, uninstall, re-install until the tail pipe was in the correct position with it not sticking out too much. The sliding pipe connections cannot be adjusted when the pipes are installed which makes this a bit of a bugger..... also had to bend the pipe hangers some to avoid pipe from contacting the frame/chassis.

I'm extremely pleased with my cat-less Piper with single muffler.

Note that during removing the stock exhaust 3 of the studs where the pre-cat lives (there are 6 in all) broke and had to be drilled out, and re-threaded for new studs - this was a real bugger and extended the install time by several hours..... Looked for a new downpipe to avoid restoring the 3 studs, but had no luck.... can the downpipe be found more easily in the UK I wonder (I'm in USA). The opening diameter to the specially made Piper pre-cat is simply enormous. Replaced all nuts/bolts with quality SS.

[EDIT]
A day or so of running with the new Piper exhaust has revealed an annoying rattle. Suspect part of the exhaust is too close to the chassis so will need to closely examine things under the car to find the culprit.... Attaching the Piper PCE to the end of the downpipe did require moving things a tad and suspect this is likely the cause.