Right just a quick question for you guys, Has anybody had any first hand experiance fitting a decat to their 250 without mapping?? I have an RST 3” Decat to fit to mine I also have a lambda spacer for the second lambda sensor, I fully intend to map it at rst, just not yet, probably in a few months time,l when the car is more a priority to spend on! so basically will it cause any issues running it, like any flat spots etc as I know on the 225 they don’t like not being mapped in. The car has a blanking plate on turbo, centre delete and a panel filter. Many thanks in advance
I’m just very impatient tbh! I have the de cat sat waiting for the car and work in a garage so don’t have to pay for fitting etc, but I’ll be waiting at least a few month before I’ll be in a position to take it for mapping.
Fine as well, have a 3 inch cgr decat fitted, still no time for remap, and not even a engine light on, just horrible smell from the exhaust and quite some turbo lag Cheers, Sent from my iPhone using Tapatalk
I was advised not to do any track days with mine, as it will run lean at full power, so i had mine put back in till i get it mapped.
I wish I'd seen this before. I'm just back from bedford having had the "check injection" message a few times (in an R26). I've just had a decat fitted and the map isn't happening until Thursday. Is that likely to be the problem? PS Ian aren't you on the way to the ring?
Hi Steve, just seen this, didn't get back till late last night, yes was on the way out. It was just what i was told, normal ish driving is okay but hammering it on a track not the best idea
To fit a decay no then not get it mapped is madness. The ECU can adjust fueling dependant on O2 sensor and mad values etc but if you go out with the range it can adapt you WILL have an issue, maybe not instantly but you will cause issues. Driving short term off boost is fine driving the car hard on boost is madness.
The ecu is more than smart enough to adapt it to suit. Mine ran for over a year and 20+ TDs and didn't blow up.
And then it blew up . Do you monitor AFR, fuel pressure, injector duty, IAT. knock. I used to and even on a properly mapped car with full knock control and wide band lambda you would be stunned to see what happens with changes to out side temp, different fuel batches, etc etc. The standard ECU may not be able to pull enough timing or adjust fueling enough for all conditions if it isn't starting from an ideal scenario. In over 15 years racing I have never blown up an engine and all have been properly mapped for the things that will change airflow and fueling. Each to their own tho but your basing your theory on assumptions, it would have been interesting to boroscope the top of your Pistons before it blew up I can almost guarantee there would be evidence of det.
No it didn't blow up, it was the original engine that then bent a rod due to water and when the engine was sold and took apart there was ZERO indication of any damage or det. In fact the guy that bought it couldn't beleive it had done 75k,said it looked like it had barely done any miles. The pistons that were in it are now in another engine with forged rods
Up to you Jamie I know where I sit with it and I have had advice from some of the best mappers around. I also understand how it all works.
Out of interest given u know about the ecu, how much timing can it take out, what band of AFR can it compensate for, what is it's knock strategy just curious. Personally I think the advice is giving is ill judged.
It's not, saying its going to blow up is a bit of a overreaction. I know multiple people who have decat, then tracked it without issues. Loads of the Ring spec cars ran stock maps with intake and decat and done thousands of laps between them. The only failure I seen was from someone who ran a poor quality map and it leaned out melting a plug/piston If course it isn't optimal, but it isn't going to die by doing so.
Just as an example the Wategate duty cycle could be up to 30% out which can lead to over boost issues and subsequnt intake temp rises this equals a lean mixture and knock so in my opinion if u change to a decat, change injectors, fuel pump upgrade, turbo change fuel px change then get it remapped.
