Issues running free flow exhaust

[daviefoster9773]

Who all has had them? My nur spec constantly blew the knock sensor. I've recently bought dravens engine and ecu however and he informed me his ran with no issues. So what is the deal with this ? My engine has suffered damage to the ringlands and the problems only happened after the exhaust was fitted. This should be a sticky because it's a grand worth of damage for the sake of an exhaust. My car ran perfectly before I fitted the exhaust.

[Peter Gidden]

A free flowing exhaust will not damage your ringlands. So no need to be a sticky.

[Martin F]

Who all has had them? My nur spec constantly blew the knock sensor. I've recently bought dravens engine and ecu however and he informed me his ran with no issues. So what is the deal with this ? My engine has suffered damage to the ringlands and the problems only happened after the exhaust was fitted. This should be a sticky because it's a grand worth of damage for the sake of an exhaust. My car ran perfectly before I fitted the exhaust.

Sounds like a coincidence, nothing more, what boost were you running ?

[Draven]

Yes i ran a Nur for a decent length of time no adverse effects. I still don't understand how a free flowing exhaust like a nur can damage an engine.

[ashley]

In theory it could allow boost creep (depending on the waste gate set up). If this means that the car was running above safe boost and was consequently detonating, and the driver kept driving it like this, then yes- you'd kill the engine pretty quick.

But if this was the case you'd expect the driver to notice the high boost levels and take their foot of the throttle and investigate the issue.

[Peter Gidden]

In theory it could allow boost creep (depending on the waste gate set up). If this means that the car was running above safe boost and was consequently detonating, and the driver kept driving it like this, then yes- you'd kill the engine pretty quick.

But if this was the case you'd expect the driver to notice the high boost levels and take their foot of the throttle and investigate the issue.

So to be pedantic (because pedancy matters ), it's the detonation that is the problem, not the exhaust.

[ashley]

Well if you want to be pedantic- it's the boost control that's the cause of the issue- presumably not containing boost within desired parameters.

The secondary issues could then be:
- Lack of ignition and fuel maps for actual boost run
- Too much advance for actual boost run
- Too high compression for actual boost run

The initial symptom would then be detonation.

The result through repeat events would be destroyed piston ringlands.

But it's all guess work based on the assumption that the free flowing exhaust has exposed an underlying issue with boost control...either way the driver should have spotted the symptoms and stopped driving it

[Peter Gidden]

But it's all guess work based on the assumption that the free flowing exhaust has exposed an underlying issue with boost control...either way the driver should have spotted the symptoms and stopped driving it

[bobhatton]

My nur spec constantly blew the knock sensor.

The information of a problem was clear, not sorting it would damage the engine next, and it did.

There are way too many people with cars changing things without the knowledge to understand what they are doing, not just MR2s but it keeps us all in work.

[Peter Gidden]

My nur spec constantly blew the knock sensor.

The information of a problem was clear, not sorting it would damage the engine next, and it did.

There are way too many people with cars changing things without the knowledge to understand what they are doing, not just MR2s but it keeps us all in work.

And ATS Racing in sales of "uprated" knock sensors...

[Peter Gidden]

Who all has had them? My nur spec constantly blew the knock sensor. I've recently bought dravens engine and ecu however and he informed me his ran with no issues. So what is the deal with this ? My engine has suffered damage to the ringlands and the problems only happened after the exhaust was fitted. This should be a sticky because it's a grand worth of damage for the sake of an exhaust. My car ran perfectly before I fitted the exhaust.

Those NurSpec exhausts are bloody lethal.

Fitted one to Craig's engine last winter, and blow me, it cracked his block a few months later.

Changed engine, fitted a Mongoose, and no problems since.

[jimGTS]

super sucks to have to replace the engine.

but can i ask what did you do, if anything to rectify the issues youve been having before this went??

i remember you had threads about faults codes, boost creep issues and blowing knock sensors.

what was done to sort these issues? or did you carry on driving the car as is?

[2mad]

Who all has had them? My nur spec constantly blew the knock sensor. I've recently bought dravens engine and ecu however and he informed me his ran with no issues. So what is the deal with this ? My engine has suffered damage to the ringlands and the problems only happened after the exhaust was fitted. This should be a sticky because it's a grand worth of damage for the sake of an exhaust. My car ran perfectly before I fitted the exhaust.

Those NurSpec exhausts are bloody lethal.

Fitted one to Craig's engine last winter, and blow me, it cracked his block a few months later.

Changed engine, fitted a Mongoose, and no problems since.

Pete you comment made me cry with laughter ..

To op the only way an exhaust can hurt your engine is if it courses creep and you ignore it .. your car more than likely developed a fault about the same time as the nur install.

Sorry about the engine though mate .. best of luck with the new

[daviefoster9773]

I ran the car on the lower boost setting. This still put the engine management light on now and again but not as before when it was on the high boost setting of 17psi. I tried to lower the settings on the Profec B so the boost wasn't so aggresive and i had a Restrictor ring fitted. I also fitted a knock sensor to the engine.

All this helped it, but occasionally the car would still put the engine management light on. I gave up with high boost and just ran it around on the 7psi setting with the intention of sticking the old exhaust back on. It then started putting oil out of the dump valve one night and running on 3 cylincers. This all happened over a period of about 1month-6weeks.

It was so bad initially that even with boost controller off so running around the 7psi mark, as soon as it hit the 3.5k rev mark, ping, on would come the light and it wasan't even boosting hard. So high boost didnt seem the issue.

Confusing, time consuming and annoying to say the least. Oh, and expensive

[daviefoster9773]

Thanks 2 mad. Dravens Engine will hopefully run no issues. I have always had bad luck with cars. 12psi is all it will be running from here on in. Cba with breaking cars all the time. My trusty williams powered 16v has been a gem since the mr2 has been broken though

[daviefoster9773]

How do you solve boost creep?

I had oxygen sensor code, overboost and knock sensor all showing

[2mad]

It then started putting oil out of the dump valve one night and running on 3 cylincers. This all happened over a period of about 1month-6weeks.

This is real bad bud wish i had an answer for you ... might be worth looking at the turbo .. compressor side oil seals

[daviefoster9773]

Yeah, i have no luck with cars mate. lol. I am half expecting the guy that is swapping the engines to tell me the turbo is goosed as well. Ill be looking for a turbo then too. lol. Compression is down on cylinder 3 so its probably a mixture of both turbo seals and the piston ringlands F*cked

[2mad]

Thanks 2 mad. Dravens Engine will hopefully run no issues. I have always had bad luck with cars. 12psi is all it will be running from here on in. Cba with breaking cars all the time. My trusty williams powered 16v has been a gem since the mr2 has been broken though

Dravens a cool dude .. cant see him stitching you up ..

[daviefoster9773]

No hardly, just mean no issues once installed and everything just works..lol