Some of you guys might remember I originally wanted to do an OBDI conversion on my car using a 90-93 300zx ECU. Reason for this is that OBDI ECUs are much easier to tune than our notoriously uncooperative 95+OBDII's. Right now we are stuck with JWT, TS or the E-manage Ultimate when/if it is finally made to work on 95-01 ECUs.

Well me and the guy that was going to do the OBDII-* OBDI conversion quickly found out how different the VG and VQ sensors and signals were and the project died, never brought it up again.

Well now he's looking at oversees ECUs using the VQ30. At first I didn't know what difference this would make but it turns out OBDII was created strictly for North America. Forgive me for being ignorant about this.

The 1994-1998 Nissan Cefiro is basically a carbon copy of our cars with 217 HP due to a stock MEVI. They use the VQ30 but run it on an OBDI ecu. They were the very first production cars to receive the VQ30. Hell, the chassis is A32.

Technically, this is a 4th gen maxima with a VI and OBDI.

Thoughts?

 

Ceasar looked into this too since they have the same thing in New Zealand. I think the MEVI equipped ones have a different harness connector. You could splice it in, but I doubt it would be plug and play. Then we would have to figure out how to reprogram those ECUs.

 

Get it working.

 

buy a 3rd gen

 

so are the obd-1 ecus able to have a program uploaded to it or will it forget it once the car is turned off?

cause if the obd-1 ecu's can work with our consult plug i we can learn how to write and upload info into it with some of the existing programs we have around.

 

He does custom harness adaptors OBDII- OBDI. The wiring part was never *the* problem, problem was that all known available OBDI ECUs we have in north america couldn't control the VQ30. Either way that won't be me gnawing at the wires with my teeth.

I guess boosted guys would benefit from this too

 

this is why iam getting a 95 max because 96 and up in new york need obd 2 interface with DMV.

 

Welcome to the club. 95 = teh best.

 

Update:

Well they are going to test it on a local guy's race 2100 lbs 240sx powered by an N/A VQ30DE-K. He ordered a Nissan Gloria ECU and he says it is even closer to my 1995 ECU than the Cefiro's ECU. The ECU cost 150$CND (130$US) shipped and he says he can get me another one for the same price.

So I will not actually be the guinea pig and when/if it goes on my car I will be 100% positive that it does indeed work. I will keep you guys updated. This is looking good so far though. If you're planning on getting a JWT ECU, hold that thought for several weeks.

 

Is he using vQ30 sensors ?

 

Yep. Just a regular ECU/Wiring swap. So if it works in his 240, it works 110% on all 95-01's.

 

nice, that 240's gonna fly... ***edit after reading your post a couple more times trying to get over my shell shock i have come up with this conclusion... dude thats like exciting news

 

LOL yeah. Especially for boosted guys. If it works we collectively tell Jim Wolf to shove it

 

im very excited to hear this..i want to see somethin made of it

 

Allen22 is already working on telling JWT to shove it. He's been working on getting his Megasquirt to work with the VQ35 he is running in his s14.

Check the later pages of this thread for details.
http://forums.freshalloy.com/ubbthre...t=1&PHPSESSID=

95's have the interface too its just in a different place. Right next to the ECU.

 

Sup Broaner, haven't heard anything out of you in a while!

I hope to have my car ready to start in a couple weeks, wiring and intake manifold are all that's left really. When I'm done I'll have a nice stand alone solution for anybody w/ a VQ.

As for the JDM ecu's, cool idea if you have the software and know how to reprogram them. What software do you plan on?

allen

 

He can tune OBDI nissan ECUs however he wants it. Not sure what he uses, but he told me rev limiter (7000), A/F and as much timing as the engine can possibly take. OBDI ecus have more options.

 

Sounds similar to a Zemulator type thing. What ever happened with all that possible development?

Allen, yes it has been a while. I actually haven't started my car since early November. I've been focusing on the rear suspension so I can actually use the power. I basically decided to do a ground up resto with aftermarket suspension links, SPL aluminum bushings, and powdercoated subframe. I should give you a ring.

You gonna consider selling these ECU's pre assembled? There could be a market for it. A lot of people aren't comfortable with soitering in precision situations. I've been contemplating running that system but I really need to get this blower on as I've had it for over a year and never even bolted it to the motor.

 

The most important thing (after the ECU), is the harness adaptor. OBDII--OBDI. After getting both, it's pick and choose which tuning tool suits you best.

 

I'd love to do a resto on this car, new suspension, chassis foam, braces, etc. that'd be nice.

I'm thinking of selling a pretuned, prebuilt Megasquirt box w/ wiring harness and all. It would have a usable base tune on it for non turbo cars so you could plug it in and start it up.

allen

 

Ok this is a dumb question but is it possible to access the ecu via the OBDII port? To see the values that is has stored? I figure its like a normal computer BIOS right? Just a bunch of preset values saved to a ROM chip. If so it should be possible for anyone (that knows what they are doing) to flash the chip and reset the values to whatever they want. I'm just guessing, because I don't really know much about computers.

 

Any idea of pricing yet?

I've been contemplating the stiffening foam but I've been wondering about flamability issues. If something should cause a serious fire will the foam add crazy amounts of high temp highly toxic fumes? Or if I need to weld on the framerails after the foam is in there will it catch fire? I guess I should find out if its permitted in the lower classes of SCCA rules. Thats probably a good guideline. Although even some of those cars have nice fire extinguishing systems.

If I'm not mistaken the stock chips can't be flashed. Anyone?

 

No the stock 4th gen chips can't be flashed. They're PROM's... read only. That's why TS and JWT run daughterboards that contain romulators (emulates writeable memory).

 

Jclaw, so if this does work, will we be able to tune them ourselves? or will we have to have this guy tune the ecu for us?

I was just about to order a jwt, looks like I'm going to hold off on it for a few weeks.

 

If it works you should be able to tune yourself with any simple OBDI program.

 

I am still working on the Zemulator. It doesn't seem so easy to get the 16 bit ECUs to work with a daughterboard. That is the way the 90-94 z32s are and the VE ECU.

I know the 4th gen OBDI ECU is the same way. Jclaw, does he already have the daughterboard working on this 16 bit ECU? If so, do you know any details if he used two 8 bit EPROMs or one 16 bit EPROM?

 

correct me if im wrong but cant you try to solder out the PROM and replace it with a writeable one?!? its only a chip

 

Yes, you can do that IF you had an EPROM to begin with. The VE and 4th gen ECU is a 16 bit ASIC design ECU without a daugherboard. So you have to make a daughterboard, solder that in and then make the ECU read the daughterboard before it attempts to read the motherboard.

Once you get your EPROM working, then you're in business!

 

so if i was an electrical engineer i can put this to play... but since im not, All Efforts Exhausted

 

Thats great Jclaw

thats what i am waiting on .. i guess it can take vtc like VG

and i assume the guy is Robin ?

 

Thats great Jclaw

thats what i am waiting on .. i guess it can take vtc like VG

and i assume the guy is Robin ?

Edit : we need to have a little chat on Vq35

there is a maxima meet over NPCLUB

 

any new news on this Mr. Claw?

 

Like I said I'm not going to know until late March or so.

 

Any update on this? Sorry to bump such an old thread...

 

Yes it is an old thread. I'm going to be using Megasquirt on my VQ35 instead.

 

Bold move man. Allen gave up on the Mega-squirt.