Jump to content
The mkiv Supra Owners Club

na-t auto info needed regarding ecu


syco

Recommended Posts

Since I have had my car I have been collecting the parts needed to convert it and thought I had got most things covered , so started reading again to refresh the memory of various processes and problems which people have had to deal with.

But during this refresher course I read something which I had not seen on other posts regarding the jdm na ecu. It stated that jdm n/a map based cars would not let you boost past 3psi and that some kind of voltage clamp would be needed.

 

Is this info correct? and if so what have people done so that they can boost to 7-9 psi. I will be doing the h/g later once I know the engine is running good with boost lol. Also if this is correct is there a difference depending on if you are auto or n/a, mine is auto .

 

All info appreciated , thanks

Link to comment
Share on other sites

You need a piggy back ecu or standalone. You clamp the voltage thru settings on the map.

The na map sensor is OK up to a bar I think. I'm running a stock sensor at 10 psi.

 

I am pretty good with a spanner but no so much on techy leccy stuff.

I have a Map ecu 1 which I got for my mr2 but never used as changed to rev3. would this sort it. if so will have to try and start understanding this clamping the voltage method as have no clue at moment. thanks for reply.

Link to comment
Share on other sites

done a bit more reading, basically you have just got to stop the na map sensore reading boost. just for info to others:

 

some have put a one way valve in the pipe to map sensor and then drilled a small hole in between the 2. Assume this is so the the sensor see's normal pressure till vacuum is created?

Also been looking at the map ecu 1 wiring diagram and you have to cut the original wire to the std N/A map sensor and connect it to the map ecu1, so think that means would not have to do the above as the std ecu is no longer seeing the boost?, am I going in the right direction here? or is there more to it?

 

just realized the map signal is still going from the map ecu 1 to the std ecu, all I am doing is taking the std map sensor out the equation, does this mean that I will still have the same cut out once boost is achieved?

Edited by syco (see edit history)
Link to comment
Share on other sites

thanks for the input guys. Yes I had noticed that a lot use the emanage. thanks for mentioning you have one but just spent my last bit of dosh buying bits and bobs lol.

I was going to do a gte ecu swap, but people said that that causes other issues to do with the auto box and I know naff all about g/boxes:( so that killed that idea. Think I will ask on the map ecu website aswell for input once I have checked abit more of what it can/can't do.

Link to comment
Share on other sites

Depends on the specs of the Map ECU, it needs to be able to clamp the std MAP sensor voltage at just below the cut of voltage, and then be able to carry on with its own sensor to be able to map for the extra boost pressure, if it can do this then your fine.

thanks,think I am slightly getting the jist of it. I have just posted this on the map ecu site. to see if it will do,hope so.

 

Hi, I am in the process of doing an na-t conversion on my jdm n/a auto. I recently read this thread: http://forum.clubna-t.com/showthread.php?t=3954

 

Which basically says that once the std map sensor see's boost it will fuel cut hence no boost. I have a map ecu1 lying around doing nothing so thought I could use this and noticed that there is a wiring diagram for it. But that it intercepts the map signal at the ecu but is connected to the std jdm ecu map signal still.

I am not to sure if I am understanding it right or not.

So my Q is does the map ecu1 get round this problem caused by the jdm na map sensor and if so , how? or do I need to do/use something else?

 

thanks

Sie

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.