HONDATA TUNING TIPS

Here are some tips to help you understand Hondata tuning. Other tuners feel free to chime in.


Which Base Map to Start with?

If the motor is completely stock then use the map for that motor. These are the exception. (of course calibrate for different sized injectors)

ITR - use JDM P30 map scaled to 1.8L from 1.6L
GSR with Skunk IM - use JDM P30 map scaled to 1.8L from 1.6L
H22 - use P72 map scaled to 2.2L from 1.8L
H22 with Euro IM - use JDM P30 map scaled to 2.2L from 1.6L
B20B - Use P74 or 75 map scaled to 2.0 from 1.8L
B20Vtec with B16 Head - use JDM P30 map scaled to 2.0L from 1.6L
B20Vtec with GSR Head and GSR IM- use P72 map scaled to 2.0L from 1.8L
B20Vtec with GSR Head and Skunk IM- use JDM P30 map scaled to 2.0L from 1.6L

In general you can add like 5-7% fuel to columns 8, 9, 10 with the hotter Vtec cams currently available.

Note: A map for a NA motor is basically the same as a boosted motor (on Hondata). Think about it a little. When not in boost your motor is running NA and when boosting it runs in the boosted portion of the map. Pretty simple.


Hiccuping and Coughing under Light Cruise

The first 7 columns of the fuel map should give you 14.7:1 (Lamda=1) air fuel/ratio. If not your car will hiccup and cough under light cruise if you run closed loop. You may also need a little more timing.

You must tune for 14.7:1 A/F if you want to run in closed loop(uses the stock o2 sensor - gas saving) operation.

Note: A lot of tuners don't tune this portion of the map and hence the car won't run well in closed loop operation.

Also Note: It maybe beneficial to run in open loop with lower than 14.7:1 in this portion of the map if your motor has too much compression for the gas that you are running.

Here's a pic showing which showing the 14.7:1 areas of the map. (This can be found under File menu, menu item "Settings", tab "Lamda" in the ROMEditor.)




Changes to the Fuel settings in the Low rpm portion of the map affects the A/F in the higher RPM

This is why you tune the lower rpm ranges AND driveability (tune for 14.7:1) FIRST.

For example, if you lean the map at 2,000 rpms you'll run leaner higher up in the rpm. Converserly, if you richen the map at 2,000 you'll run richer higher up in the rpm.

Once you get your driveablity down extrapolate to the rest of the map and take passes at wide open throttle (WOT) and clean up the WOT portion of the map.


What's a good ignition timing?

For idle it should be 16 - 20 degrees.

For WOT operation it depends on the particular engine but most Honda's I've seen like 24 - 28 total timing in the high rpm (4.5k+) and high load (3 last columns) for NA apps (22-24 degrees for FI apps).

Here's the VTEC Ignition map (JDM P30) that I like the best. Notice in the high rpm high load part of the map the timing is around 26 degrees. Note: This is very similiar to the popular Mugen and Mugen rip off maps.




Modified by Rocket at 1:55 AM 4/9/2005

 

Good info! Hard to believe you have never tuned hondata

 

basicly all that info applies to tuning anything..

for part throttle/low loads if you have a good enough ign system you can run into the 15-16:1 range to get more mileage.. every engine is different though.. some like it some dont.

i have done a few cars that like to idle at 17:1, others that wont idle at anything less than 14:1

one important thing i have found is not to get hung up in the numbers.. tune the engine where it wants to be. if it drives better and makes more power running 16:1, let it run 16:1. if it wants to be at 10:1 let be at 10:1, no one afr is perfect for all engines... same goes w/timing. our b20vtec didnt like that much timing. at wot we were running 10-15deg and made best power.

 

damn....bet those sleeves never cracked lol.

good info rocket.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Furry in your eye &raquo;</TD></TR><TR><TD CLASS="quote">our b20vtec didnt like that much timing. at wot we were running 10-15deg and made best power.</TD></TR></TABLE>

What CR are you running? and whay gas?

 

stock jdm b20b bottom end with stock 1g b16 head. 93 octane.

 

Rocket,
I had a few questions regarding timing:
1. Do you actually tune the ignition map in the lower left corner? Seems like this part of the map would pertain to deceleration primarily.
2. Is there a better/alternate way of tuning ignition timing other thank audible knock? I've heard comparing torque curves between runs is a way, however consistancy in the dyno, weather, etc ... might make this difficult. Any suggestions?

 

tune full throttle ignition on the dyno.. if the dyno is good you will see small spikes in teh tq curve

tune part throttle ign timing for drivability

if you have an o-scope you can monitor the voltage of the knock sensor and look for spikes in the voltage

 

This is the kinda info i have been looking for on this board!... keep posting!

 

You can pretty much stay outta the bottom left and top right corners...because the car will never be in those areas.

 

interesting

 

nice

 

damn good post

 

nice info, thanks rocket

 

thanks for sharing the knowledge

 

I think I might get a hondata soon. And this is the info that we need in forums.


June

 

Thx..Going to a dyno with my Hondata on the 20th with my new setup and I'll try to tune after your guidelines ..I've never tried to retard ignition that much at high rpm..Hope it'll work..Normally I tune to around 28-29..On my current map it's actually 30..daumn

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ninjanick &raquo;</TD></TR><TR><TD CLASS="quote">Rocket,
I had a few questions regarding timing:
1. Do you actually tune the ignition map in the lower left corner? Seems like this part of the map would pertain to deceleration primarily.
2. Is there a better/alternate way of tuning ignition timing other thank audible knock? I've heard comparing torque curves between runs is a way, however consistancy in the dyno, weather, etc ... might make this difficult. Any suggestions?</TD></TR></TABLE>

1. This area is usually not modded. Under deceleration the ecu doesn't give the engine any fuel so it is a non-issue. Also I don't think any of us drive in super part throttle at 6+K rpms.

2. Ignition tuning is tougher to play with. One some dyno's like a mustang dyno or engine dyno you can hold the rpm steady and tune fro maximum torque. I am guess that's how Erik's Racking does their tuning on the DynaPacks. That's the way to do it. But on DynoJets this can't be done easily.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ce &raquo;</TD></TR><TR><TD CLASS="quote">Thx..Going to a dyno with my Hondata on the 20th with my new setup and I'll try to tune after your guidelines ..I've never tried to retard ignition that much at high rpm..Hope it'll work..Normally I tune to around 28-29..On my current map it's actually 30..daumn </TD></TR></TABLE>

The JDM P30 ignition map is very similiar to the Mugen and Mugen rip off maps.

Try a little less timing and see if that helps you. Every motor is different but usually I don't like alot of timing at WOT.

Column 10 on the map never gets reached on NA motors but it is used by the ecu to interpolate for points past column 9 so column 10 is still important to set properly.

 

Could you explain why there is less timing at higher loads?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 99_SH &raquo;</TD></TR><TR><TD CLASS="quote">Could you explain why there is less timing at higher loads?</TD></TR></TABLE>

I'd also like to know..Will it increase peak hp ?? If it doesn't I will go up to my usual 29-30 ish again Anyways..I will know more next week after the dyno session

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 99_SH &raquo;</TD></TR><TR><TD CLASS="quote">Could you explain why there is less timing at higher loads?</TD></TR></TABLE>

Under higher loads, ie the throttle is open completely the density of the air is higher (full atmospheric as opposed to partial vacuum). The higher the density of the inlet charge (air/fuel) the faster it burns and hence less timing is required. Just like how boosted motors don't need as much timing. Higher inlet charge densities.

 

I was thinking of a relatively easy way of tuning the ignition timing to where the ECU "believes" it's most comfortable.
Not sure, but I believe most Honda/Acura ECUs use the knock sensor. And in closed loop with the knock sensor enabled the ECU will pull timing if it hears any knock right? Assuming this is the only case where the ECU will pull timing.
So one can datalog the total ignition advance and if the curve isn't smooth or has dips than the ECU is pulling timing because of knock. So retard at the appropriate RPM/load and that should be it. Right?
This works unless the stock knock sensor is overly active and receives false knock signals.

 

The ECU doesn't read the knock sensor after 5k rpms due to noise.

I know a tuner who uses a knock microphone to monitor knock when tuning.

 

so how do i know how lean i can run the motor during partial throttle??i'd like to go lean as i can for best mileage but dont want detonation.... would be running 92 octane and 12.1cr