I have a new addition to my garage (3rd EVO) and I 'think' the timing is a bit off on the tune.

Here's what it's got - 2.3L AMS, GT35, 272s. Unsure of the AEM version running on the car. Currently has a UEGO, but I plan on adding the serial gauge to the cluster.

What makes me think the timing is off is SOTP dyno. Subjective, yes - but here are my thoughts. The A/F is consistent 11.3 to 11.7 at WOT (depending on gear). Max boost 24psi, 93oct. Part throttle mid to high 13s AF with good mpg. No puffs of smoke on shifts at WOT.

AF reads good, no knock. Cam gears are a little off - but no more than a deg to deg and a half mostly on the exh side. Power just seems conservative when at WOT. I'd liken the car to an IX with a 3076R.

So here is my question, whats the best method to step up the timing during a road tune safely? I'm not looking for cals, just the general perspective here.

I'd be happy to give more info if needed. Thx

 

what kind of timing are you seeing now? if your not getting any detonation, than you should be fine. Do you have an EGT sensor?

 

The EGT numbers are avg. I dont have an EGT amplifier so the range is iffy at best from the gauge. I use it more as a warning than a tuning device.

I think the timing is too conservative and the engine just feels flat. I'll post a shot of the timing curve.

 

I am no tuner but I have tinkered a bit with 104 octane fuel and progressively adding timing while logging to see how much more I could get without knock issue.

My approach which might not be the best dont know. Is

I would take my last highest rpm timing cell mine being at 8500 rpm at the given load i wanted to tune and raise timing 1 degree . Then I would only raise my timing above the spoolup area of the map . In other words I didnt touch timing thru out the spool area of the turbo but once it would reach boost I would tune the area above it. So I would end up tuning from 8500 rpm down to around 4900.

Once raising the timing at 8500 1 degree I would highlight the row down to 4900 and then right click it and then calculate . AEM would then calculate the row highlight across the board.

The most that I have gone was a + 4 degree's of timing calculating the row's at 22psi and running 104 unleaded just to see how it would react.

 

Here is the timing map. Whats the consensus here - too conservative?

 

would be better to change the load to read in PSI

 

looks like a lot of timing between 4k-5k @ ~158kpa = ~23psi, however i am a 91 oct. guy

 

Here is the map in PSI. Thx for everyone's help and ideas

 

what octane fuel is that map for? 91 , 93, pump / meth ????? never mind I re-read your first post and seen its on 93 octane pump right?

If so that seems like fairly aggressive timing even at the spoolup area of the turbo. You are running a few more degrees of timing than me thru out the graph.

add a few more degree up top say from 5500 to whatever you rev to. Just start with 1 deg. increments log knock. The method that I used above for increasing timing over a range has worked well for me , as the AEM calculates the range on its own. Introducing timing at a conservitive % each time. and then you can compare maps to see the changes between each cell area to know how much more you are adding.

I have added as much as 4 deg. peak timing and then calculated the row down to around 4900 rpm. with higher octane fuel. I could probably get away with more but it has worked well , saved the maps and can load at the track or wherever when running better fuel.

 

Steel,

What you're saying makes sense. Just feels a little flat on the top. But it could be too aggressive in the middle. I'll do some road tuning and keep the adjustments minimal each time.

I suppose the car could handle another 2lbs of boost on 93. But I prefer to keep the DD map and boost on the low side.

Here is the spool rate.

 

This is a 35R correct??

The spoolup is real nice peak trq. around 4200 ? assuming that is peak boost as well?

I would like to see a few other opinions on this subject matter as well , just wonder what some other peoples approach to timing is!

what 35R kit is this? tubular manifold or cast? what size turbine housing?

 

Its the AMS 35R kit - with their 2.3L. Peak tq @24.5psi. Nice unit and good low end power. Head also has 1mm larger valves.

 

nice setup and spoolup for sure with that turbo!

what is the turbine housing?

You might be suprised that you could get away with a few more deg. of timing in the top end.

based on your map and your graph , personally I would start adding timing around 5500 rpm where trq. starts to fall off.

does it spool that quick on the street?

 

If it's anything like mine, which is the same setup but with the VSR and revolver cams, yes it drives like that on the street. My timing numbers are about the same. I wouldn't go pushin it too close to the edge on pump. Better to be safe.

P.S. the remedy to your problem is a VSR intake. =o) The 2.3 35r VSR setup is ballsy once its in boost. The torque just stays there.

P.P.S. For what it's worth I've noticed that you "feel" more up top when you have a nice gradual increase in timing rather than just higher numbers. For instance, starting a little lower and slowly climbing up.