yep its the old detonation again!!

 

modified the zed with:-

 

se-maxiflow twin pop intake

 

turbo technics 13.5 psi 360 degree turbo's

 

de-cat & stainless exhaust cat back

 

and ofcourse the se-chip!!

 

running this set up i hve had detonation which destroyed my last engine so i dont fancy it happening again!

 

runs fine with the standard chip but with the se-chip i get detonation

 

where am i going wrong??

 

any help appreceated

 

cheers

 

dewi ap

Have you checked the base timing is set properly on the CAS?

Very strange.

 

I run 15-16psi with the chip on stock turbos and it only dets in top gear, which I am not surprised at. I get 15psi at less than 3000rpm.

 

Is the timing correct? I think the SE chip retards the timing. If a tuner then advances the timing back to normal it could cause problems.

 

Stuart

cheers guys,

sorry to sound bumb but what is a cas??

 

best get the zed to a good tuner to sort out then !!

Crank Angle Sensor.

 

It basically tells the sparks when to fire. If you unscrew it and twist it clock wise I think it advances the timing. That means it waits until the cylinder is higher up before the spark. Turning it the otherway will retard it, firing the sparkplug when the cylinder is further down.

 

Detonation is when the fuel ignites itself before the spark fires.

As the cylinder moves up it compresses everything, but the fuel and air becomes hotter as it is compressed until it ignites. Retarding the timing will make the spark fire sooner, hopfully before the compression makes the fuel too hot.

 

The SE chip retards the timing slightly via the ECU to help stop detonation at higher boost. If you have had some one tuning your car, they may have used the CAS to put the timing back to the stock value.

 

 

Is what I said true? Or have I just spent the 5 mins typing a load of rubbish?

 

 

Stuart

Yes, Rubbish, and if you re read it you will see that you contradict yourself too.

 

Keep taking the pills...

Originally posted by SRRAE

Crank Angle Sensor.

 

It basically tells the sparks when to fire. If you unscrew it and twist it clock wise I think it advances the timing. That means it waits until the cylinder is higher up before the spark. Turning it the otherway will retard it, firing the sparkplug when the cylinder is further down.

 

Detonation is when the fuel ignites itself before the spark fires.

As the cylinder moves up it compresses everything, but the fuel and air becomes hotter as it is compressed until it ignites. Retarding the timing will make the spark fire sooner, hopfully before the compression makes the fuel too hot.

 

The SE chip retards the timing slightly via the ECU to help stop detonation at higher boost. If you have had some one tuning your car, they may have used the CAS to put the timing back to the stock value.

 

 

Is what I said true? Or have I just spent the 5 mins typing a load of rubbish?

 

 

Stuart

 

lots of rubbish :slap:

 

just 1 slight flaw in your logic:

 

retarding the timing actually fires the spark LATER!!

 

;)

Ahhh. yeah ;)

 

Im trying to type up Madrid Gpen golf and watch Sheff. Utd. V Reading at the same time. ;)

not trying to upset you, but should'nt you try and make your comments accurate? As others are asking for help, not rubbish, (you said it)

Dewi, chip or not you really should be at stock setting for timing, 15 degrees, any advancing or retarding of the timing to suit various loads are done through the ECU and the chip modifies this setting, never heard of a chip that operates from an altered base setting. SE usually only retard the base setting on their boost upgrades. i.e. when they bleed off from the tubs

so check yer timing first.

smithy

Take it also that the if the twin pop is the pukka kind that uses the airflow meter on only one bank of cylinders then the chip has been re programmed to multiply one bank of cylinders airflow X 2? If not you are fueling for only half the airflow and that could be a reason for detting due to excessively weak mixture. Then again maybe it wouldnt run very well either if this was the case.

 

The other type of twin pop is just 2 cone filters mounted on a "Y" branch pipe that feeds into the stock airflow meter so the afm meters all the air the engine gulps.

 

Other possibilities is an SE chip set up for 550 injectors but used with stock 370's. The squirt period would be shortened due to the bigger flow with the 550's.

 

But like Smithy says check the timing first.

Originally posted by markstevens

not trying to upset you, but should'nt you try and make your comments accurate? As others are asking for help, not rubbish, (you said it)

 

He was only trying to help surely.

Originally posted by SRRAE

Detonation is when the fuel ignites itself before the spark fires.

As the cylinder moves up it compresses everything, but the fuel and air becomes hotter as it is compressed until it ignites. Retarding the timing will make the spark fire sooner, hopfully before the compression makes the fuel too hot.

[/b]

 

If the timing is too far advanced then the full explosion will occur before the piston reaches top dead centre, thus making a knocking sound.

If the mixture is too weak then the reaction/explosion will take place much quicker causing the same thing to happen.

chrisdbx..

 

If you NEED help/info etc. The LAST thing you need is duff info. Yes he was trying to help, but in his haste he might actually do some damage someday, especially when the "help" he gave was so wrong.

As from what some other people have said set the timing to 15 degrees, SE off the shelf chips work from this setup.

 

If you still get det with the SE chip then,

 

Dare I say it ....

 

Give SE/Nisstek a call. If you are lucky there may be a version number stuck on the top of the chip, quote this to Pete, he should be able to tell you if this chip is suitable for your car.

Gotta say... if you're using a copied SE chip and it's detting then maybe you should consider booking it in with them and getting it mapped properly. It'll probably cost you less in the long-run (how much are new pistons these days?). If they've supplied the chip then go back there and get them to check it.

 

Blimey, that sounds like I'm really grumpy! Well, what I meant was you're probably better off with a custom map that's running nice rather than something off the shelf.

iv, had a look on the chip and its a se copy!!

 

but if its an exact copy of the origional chip there shouldent be any trouble with it should there!!

Only with copyright issues! A touch of discretion might be in order !