Whats this then (detonation?)

[allstaruk]

Hi guys,

Finally got my car working again now 2nd tub and all, the thing is not everytime but its happened twice now, at about 6750 rpm on WOT I have had a huge stutter and then the heat light has come on and stayed on for a second or so, is this detonation if so what causes it?

Alan

[gsb876]

Sounds like too much boost or a boost spike which will eventually lead to DET dude.

What set up is the car running ie injectors, fuel pump, standard boost, power output As might be something else to do with fueling, if you are not getting enough fuel through, might be the sparkies need changing too when was the car last serviced also ??

Gurj

[davehg]

im under the impression that if the heat light flashes 3 times thats detonation if it stays on its the injectors maxing out (providing your cat isnt overheating)

[allstaruk]

My cat can\'t be overheating as its in the garage:mmmm , I would think it is prob maxing the injectors out, tbh its running a stock pump and injectors at the moment at 0.9 bar.

I have once seen 100% injector duty, I will be sorting the fueling out as soon as places open up for the new year again.

Al

[davehg]

that will be it then, i was at .93 on stock twins and that hit about 93% injector duty so go carefull you dont want to pop it :wiggle

[allstaruk]

Right, I\'ve just been out for a test drive with passanger to do data loging, well looking at the gauges and I managed to hit 100% injector duty so thats the problem. What appears to be happening is with this free flowing exhaust and apexi I have fitted I am suffering from boost creep when the car is hot.

I have a lot more kit sitting in the gargage to fit and a fuel pump on the way and this problem should be out they way.

While I\'m getting all this sorted would a boost controller be able to keep the boost down, I\'ve got a profec b sitting here ready to be fitted.

a

[rx7veilside]

yes the profec will control the boost and will keep it to whatever level u set it

[rx7veilside]

i wouldnt run 100% injector duty cycle very often if i were u

[Carl]

Right, I\'ve just been out for a test drive with passanger to do data loging, well looking at the gauges and I managed to hit 100% injector duty so thats the problem. What appears to be happening is with this free flowing exhaust and apexi I have fitted I am suffering from boost creep when the car is hot.

I have a lot more kit sitting in the gargage to fit and a fuel pump on the way and this problem should be out they way.

While I\'m getting all this sorted would a boost controller be able to keep the boost down, I\'ve got a profec b sitting here ready to be fitted.

a

You should be able to tune the car so that the turbo\'s don\'t boost spike.
0.9 of a bar boost should not max out the injectors.
Maybe the fuel pump is tired.Your uprated one would be better.
Regards
Carl

[88GT-R]

Right, I\'ve just been out for a test drive with passanger to do data loging, well looking at the gauges and I managed to hit 100% injector duty so thats the problem. What appears to be happening is with this free flowing exhaust and apexi I have fitted I am suffering from boost creep when the car is hot.

I have a lot more kit sitting in the gargage to fit and a fuel pump on the way and this problem should be out they way.

While I\'m getting all this sorted would a boost controller be able to keep the boost down, I\'ve got a profec b sitting here ready to be fitted.

a

The boost controller won\'t keep the boost below spring pressure. It won\'t limit your boost creep either!!
Didn\'t you have a problem with your secondary turbo? Having this fixed after the mapping session will cause big trouble.
Cheers,

John

[allstaruk]

The boost controller won\'t keep the boost below spring pressure. It won\'t limit your boost creep either!!
Didn\'t you have a problem with your secondary turbo? Having this fixed after the mapping session will cause big trouble.
Cheers,

John

I have fixed the boost problem, but I will explain all this in a post I was going to put up tomorrow, I plan on having everything working before its mapped and I will get the car fully chekced out before they map it anyway.

During my test run today I think I saw 97% injector duty at a boost creep of 1 bar does this sound right?

My new fuel setup is on the way anyway so it should hopfully supple enough fuel anyway but I\'m interested in what I should be seeing.

So what causes boost creep? and why can\'t I conrtol is with a boost controller, I thought the wastegate spring was set to 5psi? Thats what I get when I unplug the wastegate soloenoid?

A

[rx7veilside]

the controller will limit the boost as wastegate springs are never going to be 1 bar as u wld be spiking all over the place..of the spring is 5-7 psi u cld then use the controller and turn the setting right down to whatever boost u want and the profec will then bleed off overboost

[strange_days_uk]

Al,

If you see that warning light and 100% duty you could be doing untold damage to your car.  If it ain\'t getting enough fuel, it gonna get very annoyed at you !

Get it mapped and get your fueling right, I had a similar problem when mapping my car on stock twins at 0.9 bar, I would hit 100% duty at around 5500 rpm.  bad bad

[allstaruk]

I\'m aware the 100% duty is bad, and so is a lack of fuel its only happened twice the first time I had no idea what was going on and the second time while was out trying to find out what was going on, now I know I won\'t be doing it again.

I\'m not having the car mapped till I have everything fitted as its all sitting in a big box and I\'m just waiting for the last few bits to be done then its time to start spannering.

A

[allstaruk]

Might well fit the boost controller today though, can someone point me in the right direction of where to fit it and can I use 4mm vac line or do I need to go and get some 6mm, also isn\'t one of the lines I will be replacing one with a pill in it, do I still need this?

A