A2A Maf tuning

[VX L67 Getrag]

I thought I'd start a fresh post just tackling this 1 issue as there have been other post's from other people with random tuning inquiries but this is the main specific thing I've had an issue with.

With the A2A plate & cooler there is obviously a big rush of air in waiting & delay so on cold start up you notice this but also when changing between park/neutral to drive/reverse.

Has anyone found an exact way to counter this?

I know fudging the base airflow helps, I've also tried adding steps to shift IAC tables & scalars, but most time delays are already zero'd in calibrations so that doesn't help & wondered if there's other ways to counter it?

I have also even blocked off the by-pass sections of the A2A plate on this particular car & tried running the maf on the charge side but still doesn't seem to help, seems the same whether it's on charge side or air filter side.

[ejukated]

which ports on the A2A are blocked? Is it cammed? you have to make sure the bypass isn't interfering the metered air getting to the engine this required hardware mods depending on the setup. and get the idle spark right and you wont even notice a P/N - D transition.

[VX L67 Getrag]

I cleaned up the internals on the a2a plate for the transfer of the bypass & put welch plugs both sides!

Yeah I haven't actually adjusted the spark idle but know I did on last car & still couldn't get it perfect especially with the p/n to gear transition!

[ejukated]

so you plugged the bypass that goes through the plate and milled the M90 bridge out? that takes care of the airflow path.

[VX L67 Getrag]

Not sure what you mean by milled the M90 bridge out, I have got the M90 bypass butterfly stuck shut (manually)?

[Schwuppes]

if it makes you feel better... mine's kalmaker mafless and it still stalls sometimes when shifting from D into reverse lol...
Also idle hunts pretty bad when in N or P

cammed though

[krusty]

if it makes you feel better... mine's kalmaker mafless and it still stalls sometimes when shifting from D into reverse lol...
Also idle hunts pretty bad when in N or P

cammed though

That's only because it needs a little more time on the tune. To be expected when it's cammed A2A, not many guys have the time to get it 100%. Mafless is the way to go for A2A. Maf is just a shit fight and you need to retune the whole iac parameters to get it right. Every car been different it's just not worth it timewise

[ejukated]

if it makes you feel better... mine's kalmaker mafless and it still stalls sometimes when shifting from D into reverse lol...
Also idle hunts pretty bad when in N or P

cammed though

there is no reason why it should be like that. I did my first cammed A2A L67 6years ago and it took more time than usual but it behaves like a stocker and still runs the exact same 1/4 and power today as it did back when we first tuned it. It lives a hard life too ha ha

[The1]

The IAC table in question would be the IDLE Airflow learn table? RPM Vs Gear and G/S of MAF airflow, this controls how the IAC responds, ive tried logging with history table and using that either via MIN/MAX before but had no luck, havn't had time to revisit myself, but there would have to be a way to gather the right data for this table so the IAC responds correctly to the airflow. There would have to be a point of anticipation, rather than datalogging unfortunately.

[0081(2)]

Not sure what you mean by milled the M90 bridge out, I have got the M90 bypass butterfly stuck shut (manually)?

I have been looking into this lately and it looks like the best option is to block the hole in the A2A plate and mill the bridge out see pic outlined in red and a little of the bypass tube

Charger porting.PNG (222.19 KiB) Viewed 4493 times

this will allow the air to recirculate but it must pass through the cooler to get to the motor.

Do you think that moving the maf to the cool side and installing some kind of external IAC to just before the maf in the new location would help????
that or either convert to fly by wire and have 2 throttle body's. who is up for writing that code....