EFILive Turbo Tuning Questions

[jckleewein]

My 4094R turbo has a lot of lag in it at 5800’. Correct me if I am wrong, but my understanding is that decreasing the timing table down low will help spool the turbo quicker. My question is how far out in the table should this adjustment be made (to 1400, 1500, 1600 RPM)? And at what mm3 value should I start adjusting at? How safe is it to use negative degree angle numbers?

JC

 

[sweetdiesel]

When does it start to spool? As in what mm3 and what is the timng

Have a friend help you log you tell him when to start and stop the log then review that

timng adjustments can be as lil as 0.5* and make a difference Jut keep going until you notice a difference

it is useally lower mm3 and lower rpm range that you need to adjust and watch you shifts

 

[Mike]

Start a log, put truck in drive. Hold brake and go pedal down for a few seconds. This would be the start of tuning rpm. If rpm increases on next try, you are on the right path.

 

[jckleewein]

I am trying to get the truck to run good from a dead stop with out doing a boosted launch. From a dead stop, release the brakes and press on the go pedal. I am going to decrease the timing in the range of 30 mm3 at 300 rpm to 120mm3 to about 1500 rpm. Just wasn't for sure if that is the correct range that I should be adjusting, and how much is acceptable. Is negative timing okay?

 

[racinmike77]

I wouldnt mess with much below 1000rpm I consider that idle.

 

[KEVINL]

its gonna be tough at 1000' feet mine didn't have anything below 2000Rpm

 

[sweetdiesel]

I wouldnt mess with much below 800rpm I consider that idle.

Im with mike

 

[[email protected]]

I tried to find out how much timing effected spoolup so I timed it. With low timing in the range from off idle till aout 2000-2500rpm (-1-1 degree advanced) it went from idle to 30psi in about 3.6-3.75 seconds. With timing at about 4-6 degrees advanced it went to 30psi in about 4-4.2 seconds.

I timed it with efilive and its probably un scientific but thats the only way I knew how to do it.

Take a log from idle to 30psi to see how long it takes.(somewhere around 30psi is where the stock LLY map sensor stops reporting boost so thats why I used that boost number.)

 

[jckleewein]

I tried to find out how much timing effected spoolup so I timed it. With low timing in the range from off idle till aout 2000-2500rpm (-1-1 degree advanced) it went from idle to 30psi in about 3.6-3.75 seconds. With timing at about 4-6 degrees advanced it went to 30psi in about 4-4.2 seconds.

I timed it with efilive and its probably un scientific but thats the only way I knew how to do it.

Take a log from idle to 30psi to see how long it takes.(somewhere around 30psi is where the stock LLY map sensor stops reporting boost so thats why I used that boost number.)

Thanks for the information. I was planning on timing the run the same way. Did you see high egt's?

 

[[email protected]]

I don't have an egt gauge, I don't want to mess up my stock manifold.

 

[Mike]

For what it's worth, 38.2 actual psi is logged fairly accurately.

 

[[email protected]]

Since I have a lot of maf limiting (almost no smoke) I don't think egt's would be high.

 

[rcr1978]

Since I have a lot of maf limiting (almost no smoke) I don't think egt's would be high.

You might be surprised, hope you don't drag any trailers around up long grades. Around town with a unloaded truck probably nothing to ever worry about.

 

[[email protected]]

Nothing heavy yet. My truck rarely sees heavy loads on the engine for more than about 15 seconds.


What I don't get about spoolup is how slow it feels if your a 0 boost. I would think the engine would still be able to go since its still fueling about 40mm3 with pretty good airflow. I guess its just the power difference between no boost and full boost.

Ive hear LBZs and up spool almost instanly, I know my stock turbo LLY takes about 4 seconds to full boost.