93 ecm TBI vortec

[madmath]

hi im new here around here and around tunning last winter i buit a 87 TBI engine here's my setup
87 base
99 vortec pistons
906 stock vortec head
comp cam roller rocker
gmpp intake
46mm bored TB
petronix coil
XE256H camshaft
bbk underdrive pulley
ebay headers with 3" Y pipe
18psi spring not install yet
10 degrees set on distributor
16168625 ecm

now its time to tune it but my probleme my headers are get red around 1500rpm the engine warm up really quick and not turning smooth im a little scare of guetting it on the road i have a wide band and APU1 from moates
my questions is i can do something before getting on the road and do my datalog i don't want to burn my engine

Thanks Mathieu

[Kitch]

Your headers might glow red if you were on a dyno at W.O.T. but I'm guessing you weren't, so that's not a good look.

Can you post your current .bin file so I can have look and compare to mine as I have a similar combo.

Where do you run you PCV valve back to, it should go to the front of your throttle body.

When you say 10 degrees set on distributor, is that at the crank with a timing light and the the plug in the harness unplugged so you are in base timing mode?

[madmath]

no i was not at wot only at 1500rpm my pcv is plugged in front of my tbi and yes my timming is set at 10 degres with a timming light but the harness is still plugged on

[Kitch]

So there is normally an inline plug in your wiring harness that you need to unplug when setting the base timing for your vehicle.
If you haven't changed anything in PCM yet the base timing will be probably set at 0 degrees (but pays to check), you can check that out by connecting your laptop and viewing it in Tunerpro (I'm assuming you've had a laptop previously connected?).
For example; if the value in your current .bin file is set to 0 degrees then you need to set the timing at the crank to 0 as well.
You can only do that accurately when you temporarily disconnect the in-line plug in your harness to put the PCM into base timing mode, if you didn't do that when you set your timing to 10 degrees then you'll probably find it's retarded at the moment because you'd have set the PCM's assumed reference point incorrectly.
I've reprogrammed my van to hot idle at about 24 degrees but with the base timing set at 0 degrees.
In my case if I hadn't put it into base timing mode when setting the timing but just set it to 10 degree at the crank I would have effectively retarded my timing by 14 degrees.

[madmath]

thanks for the informations ill try this tomorrow ill try to put it at 0 degrees i only change the egr setting to turn it of and put the vortec timming map from davew in my .bin for now:thumbsup:

[Kitch]

All good.
You can easily check what your initial spark is set to in your .bin with TunerPro, as per my photo.
It's really important that you find and unplug the connector when setting the base timing, generally the engine will not idle as good when in base timing mode but you should notice it idle better when you plug it back in after setting the initial timing.

Setting the base timing by unplugging the inline connector and running the engine will set a fault code (you can check for fault codes with TunerPro), you can also clear the fault code with TunerPro (if you've set it up to do that) or pull the PCM fuses/disconnect the battery to clear the code.

Sometimes it pays check that when the mark on the harmonic balancer lines up with the timing tab the piston in number one is actually at TDC.
Occasionally the outer ring can slip on a well used or damage harmonic balancer or aftermarket timing tabs or timing covers need to be checked for accuracy.
I don't think that's your problem but if the simple things don't make much of an improvement you need to check out some of the less likely ones.

[madmath]

thanks for the information ill check it this morning i know why i need to disconnect this little wire now :rockon: