you guys think tuning the engine for the best air fuel ratio would help alot after getting some mazzuri headers??

 

Yes it would. But you can't crack the codes to do it.

 

so why is the toyota ecu so hard to crack again? I have a feeling the uncrackable new GT-R's ecu will be cracked before ours is...

 

Why do you need to crack the codes? Doesn't Gernby have a piggyback that does Air/Fuel tuning?

 

i dont think you need to crack the codes to simply use an air/fuel controller
Jermey (dude with nitrous) has one

 

From what I understand, to do a true "tune", alter the a/f tables and the timing tables, at differing rpm's you need to go into the computer. You would only alter these variables at full throttle or closed loop settings. In regular driving on open loop the standard settings would be used. If you could open the computer these could be adjusted also. From my experiance watching LSx engines, they all ran rich after a header install, so the computer has to take away more fuel for the proper O2 readings just cruising around.

 

because there is a lot of security that goes into a toyota ecu. the GT-R will definitely be cracked shortly just because there is a market for after market parts for this car because of it's following.

all you really need to tune air and fuel ratio's is an APEXi Neo and tap into the stock ecu, i know someone one here has one hooked up. that is all you can really do, other then that timing ect can not be changed.

 

If this header is any good, then I would expect the AFR to be leaner than stock after installing them. I've never heard of a good performance mod causing a rich mixture on an NA setup. I've always believed that a piggyback ECU is generally most beneficial on a stock vehicle, then slightly less beneficial with each good mod after that since the unadjusted mixture gets closer and closer to optimum with each mod.

 

hmm well it would be nice to expect that. but its nice to know we have options likfe using and SAFC if thats not the case

 

The IS300 headers all run in the 10:1s when the header is installed and most pick up another 10 hp or so when leaning it out.

On the IS250 the ratio was a bit lean, I think it was mid to low 14:1s on the low end, top end however it was down to 11s.

I think the biggest gains on this car would come from tuning the timing, as it was all over the place on the dyno if you just mashed it.

 

Would tuning the timing involve cracking the ECU?

 

You can definitely tune the air/fuel because I have a greddy e-manage ultimate piggy-back and i have been able to tune those numbers. I cant wait to get these headers on and see if a retune is going to help.

 

nope..........

 

I wouldn't feel at all comfortable altering ignition timing using a pigg-back ECU (e-Manage).

 

^^ explain.. you have a custom piggy-back ecu...