Hi,
I was working on a car from my friend.
The B16A2 engine runs great.
I see in the software, that vtec is comming in, at 5000 rpm.
But i know from another b16a2 , he puts it at 5700.
What o you think is better ? I think both engines are standard, ore a bit modificated.
And what do you think about the timming settings?
The car is used for racing in the sand.

 

Timing looks good. 30-31 at full rip is normal.

A dyno sweep helps figure out VTEC crossover best. It should be smooth. If it 'kicks', try lowering it more.

 

thanks a lott.
Dyno is the best, i know.
The difference in ignition degree, from 4000 rpm, till 8500 rpm is just 1 degree, is that normal ?

 

What fuel is being used ?

 

petrol 98

 

Yes, with these motors, they reach MBT around there then stay fairly flat. Occasionally a slight drop in timing at very high rpms.

 

thanks , just back from a day racing, i put the vtec at 5700 rpm, fuel presure at iddle 40 psi, vacuum connected, car runs great, but sparks are still very white.

 

Did you get datalogs? What's afr's like under load?

40psi idle with vacuum disconnected from fpr is a little light. Spec calls for like 43.5 and most people I think just do 45. Little rich is Ok

 

next time i can try to make a data log.
i see the afr table load , in megasquirt, all same setting 15.7.
40psi idle, vacuum connected, but at idle the vacuum is not enough, when i make more rpm, its go to 45 / 47 .

 

Figure out the fuel pressure. Look at Honda's manual. Fuel pressure goes up when vacuum goes down. The pressure differential between the fuel in the rail and the air pressure in the manifold should always be around 45psi. If you were boosted, under boost you will increase fuel pressure. Because if not, you wouldnt have enough pressure in the rail to push the fuel thru the injector to atomize the fuel.

Target AFR table needs configured better. Target 12.5-13 under full load without boost.

You are supposed to set up the target afr table, then adjust the base fuel table so that it hits the targets in target afr. Once those match, you can adjust only the target afr table to affect fuel. Thats true volumetric efficiency tuning. You dont tell the ecu how much fuel to give it, forsay, you tell it how effective it is at moving air at a given engine speed and load, and math determines the amount of fuel to match the air.