BIN file for 64pt VQ Map

[towbar]

I have been reading on some old forums about BIN files modded for a 64 point VQ table. The stock CA18 Bin file only uses 52 values from approx 1 to 5.1V The modded BIN's could use all 64 values allowing the ECU to maintain a smooth idle when MAF voltage was below 1.0V (with large MAF's such as Lightning).

I know some guys had modded the code for Euro ecu's but don't know if it ever really worked out. Is anyone using one of these modified BIN's successfully?? I need mapping below 1.0V to get my car idling right.

Thanks
Jeremy

[float_6969]

Not too many ROM tuners left on here anymore.

[tommey]

I have a friend who uses a 4" pipe with a z32 sensor in it as an AFM.
Works well with his Nistune, i could ask him if he has what you need?

[Nunook]

Its funny that this post came up cause i was looking at my old maps the other day. I have one that was downloaded from someone called Dan. I cant even remember. It says 450cc rb maf.

If he is still on here and doesn't mind Ill send it to you.

Me on the other hand have been using the s14 sr20 ecu with good results.

[towbar]

Thanks for your replies. As far as I know Nistune uses the normal 52 point table. That works ok with the Z32 MAF.

Nunook. If you have an old BIN file that might be set up for 64pt table, then I would certainly appreciate a copy to try. I think not too many guys are playing with these ECU's anymore. Like you say the SR20 ECU would be another option. Is there much involved in doing the swap? I guess a lot of loom splicing?

Jeremy

[Nunook]

No loom splicing, there is a certain model s14 St ecu that has the same plug. You just have to Repin some of it. I learned it here. So if interested in that give a search and you should find something.

I'll try to post the file tomorrow. Remember the address file is going to be different depending on the software your using.

[towbar]

That would be great thanks Nunook. I'll have a search on that S14 ECU in the mean time.

[Nunook]

Ok this is what I have. Dont know if it will help

The bin file
https://www.dropbox.com/s/504xsvixqt3cx ... RB_dan.bin

A small txt that I put some ecu model numbers and something about the memory addresses relating to the expanded afm points.
https://www.dropbox.com/s/ehyqok06m7j9q ... t_info.txt

If only I could remember exactly what it meant.

[towbar]

That BIN file certainly looks modified in the VQmap area. I found some info similar to your notes at ECU2.forumwise.com, but the forum seems inactive now. I'll be able to try your BIN in a week or so, so fingers crossed.

Thanks for your time and effort. I'll let you know what happens.
Jeremy

[Nunook]

Oh forgot to mention, if you didn't already figure it out, the bin file is for 450cc inj and rb maf

[towbar]

Didn't work out unfortunately. The bin file still won't read values below 1 volt.

[blownhemi]

What injectors and MAF are you using? I have perfectly good idle with 1000cc and the E60 MAF (pink?, RB25DET late or RD28), and the stock 52 VQ cell program, with the E60 VQ table just copied in (except the bottom 12 cells).

But actually, that's beside the point, because you don't need the sub 1V range to tune your idle.
You need to tune your *injector latency* to get a good idle.
Injector actual open time = injector latency +Theoretical Pulsewidth (approx. from fuel correction table)
The injector latency is constant throughout the rpm+load range. But TP varies, and it increases with rpm+load. But at low rpm and low load, TP is very small compared to the latency value, so small, that it barely influences anything at that point, it is mostly dictated by injector latency. The bigger the injectors, the bigger their latency, and the smaller part the TP plays in determining your actual final injector pulsewidth.

I'm 99.9% sure the ECU does not use the VQ+fuel table for idle (TPS idle switch), it uses closed loop. I'm basing this theory on the experience, that no amount of fiddling around with open/closed loop and fuel correction values has fixed my lean idle. Then I read somewhere (ECU2.forumwise, probably) about the latency/TP/idle relation, and it all made sense. We pushed up the injector latency, BAM!, perfect AFRs at idle. (meaning the usual closed loop AFR hunt around 14.7, but still better, then 17+s, as before)

I still think a ROM tune is the cheapest, simplest and best value option, and perfectly adequate for 350 whp, if not more. You just have to have some understanding of how fuel/timing control works in general, so you don't blow up your engine. (And by far a more elegant solution, then piggybacks, I think.)

[float_6969]

I agree with the fact that ROM tuning is a great tuning option. FAR better than ANY piggy back. I'm running into this issue with my Mazdaspeed Protege right now. There is NO stock ECU tuning options for this car. Piggyback or standalone, that's it. It's VERY annoying. Anyway, even if the ROM is a bit of a pain to tune, at least you have it as an option!

[towbar]

Thanks for the comments. The MAF is a Ford Mustang MAF and idles below 1V on the ca18DET. That's the problem for an CA18 ECU.

Certainly injector latency is critical to good idle. And I wouldn't use a piggyback unless there were no other choices.

[float_6969]

You must be using a HUGE Mustang MAFS if it's idling below 1v. Which one are you using?

[blownhemi]

Let's try another approach. What is actually wrong with your idle? Too rich, too lean, too high, too low, fluctuates a lot? How about the same things cold and warm?

[towbar]

Actually I sorted it out by fitting a Z32 MAF and re-tuning. I just posted the follow-up to warn that using a Mustang or similar Ford V8 MAF is not a good idea with the CA18 ECU as MAF idle voltage is below 1V. Most Nissan ECU's will read down to 0.1V but the CA18 ECU only reads down to 1V. THis causes an extremely rich idle.

[float_6969]

That's odd, is that a hardware limit, or a software limit?

[towbar]

Software. The lowest value on the table is around 1.0V