tbi cold cranking parameters

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10-31-2013
mamigacz

tbi cold cranking parameters

In turnerpro ($42-1227747-V5.9.3.xdf) there are two tables that affect fuel when cranking:

-cold start crank vs %RPM
-crank AFR during cranking

From what I understand the "cold start crank vs %RPM" multiplies the BPW (base injector pulse width) by a value (listed in the table). This value changes as a result of the (cranking RPM/minumum RPM to consider the engine running *100).

From what I understand the "crank AFR during cranking" adjusts the cranking AFR based on coolant temperature.

My cold cranking starts are longer than they should be. The warm cranking starts are better, but I think they could use improvement.

Do I just decrease the AFR's listed in the "crank AFR during cranking" table?
Do I increase the multipliers in the "cold start crank vs %RPM"?
A combination of both?
11-20-2013
04hdstd

did you happen to find anything out? I am in need of the same info
11-20-2013
EagleMark

Quote:

Originally Posted by mamigacz

In turnerpro ($42-1227747-V5.9.3.xdf) there are two tables that affect fuel when cranking:

-cold start crank vs %RPM
-crank AFR during cranking

From what I understand the "cold start crank vs %RPM" multiplies the BPW (base injector pulse width) by a value (listed in the table). This value changes as a result of the (cranking RPM/minumum RPM to consider the engine running *100).

From what I understand the "crank AFR during cranking" adjusts the cranking AFR based on coolant temperature.

My cold cranking starts are longer than they should be. The warm cranking starts are better, but I think they could use improvement.

Do I just decrease the AFR's listed in the "crank AFR during cranking" table?
Do I increase the multipliers in the "cold start crank vs %RPM"?
A combination of both?

SOrry I missed and no one else helped with your post! :rolleye:

Need to know more about the engine mods because if the VE tables are not right FIRST! There's no reason to start messing with this stuff.

-cold start crank vs %RPM = "Stretches BPW if eng cold & NOT RUNNING based on percent of engine running RPM. While Cranking!"
-crank AFR during cranking = "IIRC is AFR during Crank only!"

These ECM do crank longer when cold then hot. So is it a nature of the beast or are you flooding when cranking? What's the issue?
11-20-2013
mmigacz

I think I jumped the gun on asking this question. I put a TBI on a 351W, in a boat. I was able to start the tuning process in late September. I live in Wisconsin, and the boat is now put away in storage (I can't play or tune with it anymore). I started with a stock, ACSC, 350 truck bin. There were issues after running it the first time. Since then, I know I should of decreased the BPW from 135 because I have 15 psi of fuel pressure. Also, the engine is slightly modified with a mild cam, gt40p heads and performer rpm intake. When spring arrives, I have bunch of changes to try. In the meantime, I'm trying to gather as much information as I can, so I can intelligently tune the boat when it comes out of storage.

I really do appreciate the feedback I have been getting from eaglemark and others from my other posts. These forums have been a big help.