Tuning Guide For An Mi16

[unariciflocos 49 1 Cars]

I'm in the process of trying to tune my Mi16 with bodies, 11:1 CR and a PeterT stage 2 cam and I have a few questions:

 

1. Would I be right to assume that load sites range from 40 kPa and 101 kPa since my application is N/A? I only get 45, 50 kPa at idle.

 

2. Would I be better off with MAP or TPS for the load sites of the VE table? Same question for the ignition table, since I saw that the default ignition table uses TPS and only goes from 0 to about 50% TPS. Does the ECU just use the 50% row for WOT? Would I be better off using MAP as well for the ignition and using the full range? What about the Lambda target table, MAP or TPS?

 

3. There is no third question, but any advice is welcome

 

 

And please, if you're going to answer take it to a mapper or professional, save yourself some effort and don't bother answering.

[DrSarty 90 1 Cars]

Hi:

 

No expert, but I'd say the following:

• With bodies, you'll be using a TPSe (throttle position sensor), and you'll surely need values above 50%?
  
• My 2.2 Mi was mapped 3 times (with build changes in between), all with TPSe, Inlet Air Temp (IAT), coolant temp and crank position only - no MAP sensor
  
• We mapped using a lambda probe firstly up the tail pipe, then (with Sandy) using a lambda probe in the factory position at the base of the downpipe - don't know about which table to use
  
• I believe the cam timing required on PeterT's inlet is a 99% match for a no.4 OE pulley
  

Not sure if that helps, but worth throwing in the mix from experience perhaps.

[unariciflocos 49 1 Cars]

I tried using TPS but the readings seemed a bit erratic and non linear, maybe my TPS sensor is dirty or faulty, that's why i used the factory MAP pipes of the throttle bodies with a buffer tank to smooth it a bit and the readings seem very usable.

 

Just wondering if it's common to only use TPS to tune ignition up to 40% or maybe 0-40 the is full range of the TPS, 40 being WOT.

 

The lambda probe is in the downpipe in the factory bung, timing wise I'm using a no 4 pulley on the inlet and a no 2 on the exhaust, haven't used the offset keys from Peter.

 

Also have IAT, but I'm unsure about which route to focus on, TPS or MAP, I guess MAP is a better indication of engine load? Currently VE is on MAP and ignition and lambda target are on TPS, but I'm thinking of moving them to MAP as well.

Edited May 15, 2012 by unariciflocos

[welshpug 1,622]

sounds like your TPS needs replacing.

[petert 550]

It's normal to only have 100kPa of range on a N/A setup. -50kPa is to be expected with that cam. A std cam will give a constant -60+ kPa at idle. My recommendation would be to map the fuel on TPS and the ignition on MAP.

 

Are the fuel load sites user customisable? Ideally the load points should be log rather than linear. Eg

0%

1%

3%

7%

15%

30%

then every 10% to 100%.

This allows for the non-linear air flow as you open the throttle. MAP is certainly a more accurate and faster measurement of engine load if you have the vacuum.

[petert 550]

Also, when the TPS is functioning and calibrated correctly, you should get a 0-100% range. Some ECU's will automatically set the range, whilst others have a manual calibration tool. If fuel is being mapped by TPS then the target AFR's should also be on TPS.

[unariciflocos 49 1 Cars]

All my sensors are calibrated to be spot on.

 

Thanks for the input Peter, I'll make the changes and come back with the results.

[unariciflocos 49 1 Cars]

After being away for a while I finally had some time for the car, so I did some digging and found two wiring errors in the TPS loom, both my fault and now the TPS works spon on.

 

Started tuning, controlling VE, Ignition and Lambda by TPS, MAP seems to jump to atmospheric as soon as I touch the throttle. Unfortunately after about 10 km I spun a shell on the number 2 rod so I'm at a standstill until I change the crank and shells. Oil pressure light only came on after the shell had gone so oil starvation was not the cause.

 

Will get back with progress.

[unariciflocos 49 1 Cars]

Engine is rebuilt, did some on the road closed loop tuning and except for some hesitations at 1% throttle everything is fine. Above 2% throttle everything is perfect. Can't measure the power, but the clutch has started slipping under hard acceleration, so I imagine it's a fair bit more than before when I had it measured at 132 ATW.