Zeitronics ZT-2 Wideband - Firewall access point

[Malibyte]

Hey all -

I have everything ready to install the wideband...wiring diagrams, etc. and am ready to put this thing in. However, I'm wondering how to get all the wiring for the sensor itself, the EGT and boost sensors into the passenger side under the glove box, where I'll be stashing the brain.

Anyone else who has done this - did you put another hole in the firewall to do this, or go through an existing hole?? It doesn't look like it'll be easy to get anything else through on the right side, and I DON'T want to pull out the heater core, etc.!! Looks like it'd be easier to simply put another hole in the firewall and get a grommet to fit.

After I've got the wiring all done I'll be heading over to a local shop to get the bung installed in the downpipe, then I should be good to go....!

TIA -- Bob

[SilverMk2]

I squeezed the AEM wideband and other EMS wiring thru the factory plugged hole down by the speedo cable come thru the fire wall.

[Moorman]

Bob,

You can find an angle that works using the main harness hole w/o taking out anything more than the glovebox. I pushed a wire coat hanger through so I could tape the wires to it and pull 'em back out.

[Malibyte]

Thanks, guys...I'm going to try Jason's method first, then if that fails, go with Aaron's suggestion. Complicating the passenger-side access is the damn brain for my video/audio head unit, which is sitting under and behind the ECU. Will let you all know what worked.

[williamb82]

dont forget you can mount the brain where the factory sub used to be, thats where i mounted my 7m ecu. much easier to fit there the nthe stock location. lol. im lazy. :P

[Junkie]

Bob,I have used the AC drain tube hole on the correct side of the car also.

[Malibyte]

Well, I finished installing it today! I went through the harness grommet as Jason suggested; came out nice and clean. The display fits nice and neat above the stereo head unit. Only a few more things to do:

(1) Install a 3.5-ohm resistor across the stock O2 sensor plug to stop it from throwing a check code. *** Does anyone know what wattage rating I need for this resistor??? *** I want to make sure I don't cook anything in the ECU!!!

(2) Put all the spaghetti back together behind and under the glove box

(3) Install the software on my laptop.

I had a chance to take it for a short run out on the freeway. At low throttle, it's sitting right around the mid 14s. However, when I tromp on it, I'm still rich...low 10s, despite leaning it out almost as much as is possible with the S-AFC. We'll see what I get on the laptop.


Bob

[Junkie]

Bob,Rundown on your mods again ? You should have plenty of tuning room,unless FP is cranked up.I had 780's in O's car,stock mkiv pump,stock fpr,and tuned from off the scale,to 11.7-12 across the load range.Back to 550's now,and still stock fpr,haven't had time to get it above 11 since engine rebuild."780's go into my 83L ;)"

[Malibyte]

Bob,Rundown on your mods again ? You should have plenty of tuning room,unless FP is cranked up.I had 780's in O's car,stock mkiv pump,stock fpr,and tuned from off the scale,to 11.7-12 across the load range.Back to 550's now,and still stock fpr,haven't had time to get it above 11 since engine rebuild."780's go into my 83L ;)"


Shawn:

Motor mods are:

550cc injectors
Lexus AFM
Walbro 255 fuel pump
RRFPR
Innovative CT-26 turbo rebuild with 60 trim
JBL 3" turbo elbow
3" Brullen cat-back exhaust system
AEM adjustable cam gears (set at zero right now, so really not doing anything)
BF front-mount intercooler
Greddy oil-filter relocator and oil cooler
HKS SS blow-off valve
ACT street clutch
Fluidyne radiator
HKS open-element air filter
Greddy Profec-B Spec-II boost controller
Greddy turbo timer

I'm thinking I may have to tweak the FPR or the AFM a bit....

Thanks
Bob

P.S. Why put the 780s in your '83? Because they're gettin' ready to jump in there themselves if *you* don't put 'em in ?? :p

[Junkie]

P.S. Why put the 780s in your '83? Because they're gettin' ready to jump in there themselves if *you* don't put 'em in ?? :p

550's have more support from the AEM crowd for the moment,easier to get runable maps to tweak.So,I inherited the 780's,and if I go EMS I'll probably use the SDS to make tuning them a bit easier.When I finaly get timing control,I want to run 21-25psi thru the auto :zzzzz:

[935motorsports]

RRFPR

It's an aeromotive type right? What is your fuel pressure?

Since you have no SAFC type device, all you can do is lower the fuel pressure. Normally the lex/550 combo works without going too rich, but the walbro and the FPR are changing things up.

[Malibyte]

RRFPR

It's an aeromotive type right? What is your fuel pressure?

Since you have no SAFC type device, all you can do is lower the fuel pressure. Normally the lex/550 combo works without going too rich, but the walbro and the FPR are changing things up.

Robert::

Actually, I *do* have an S-AFC, and it's leaned out somewhat (-15 to -17% from about 3K up). I may have to go lower, maybe -25%. Will try that later today.

Fuel pressure is around 30psi at high idle.

Bob

[935motorsports]

Wow, so much going on! I did not see the SAFC in your list, sorry.

Is it 30 psi with the vacuum line pulled or at idle? If at idle, check it with the line pulled. You might have to end up at around 26-30 psi of fuel pressure with the line pulled.

Keep in mind that the lex itself is already pulling out 20-25% depending on the screw. Then you have -17% on top of that. As you know, the more you pull fuel, the more you advance timing. Many of the best 7ms have popped due to excessive SAFC "leaning".

How thick is your head gasket? Is this a REBUILT or just a used JDM motor?

[Malibyte]

Oops, you're right, I forgot to put the S-AFC on the list. :p

30 psi at idle, jumps up to about 33 with the vacuum line pulled.

I believe the head gasket is a 1.5mm; ARP bolts.

The head was redone, with a mild port-and-polish job, but the bottom end is non-gone-over JDM.

[935motorsports]

So 33 is your base. Try 28/29 and re-test.

[Malibyte]

It was set pretty uch as low as it goes...I was able to drop it from about 30 to 27 at idle; trying to adjust it with the vacuum line off isn't very helpful (reading doesn't change much). Anyway, I bumped up the S-AFC a few percent (positive), as I have dropped the fuel pressure by about 10%. Will give it a run today and see how it looks.

[935motorsports]

I forgot to mention. Make sure that you bypass the stock J tube on the side of the engine. I assume you already have, but if you have not, please do so. That will make it easier to lower your fuel pressure and should help the overrich in the top end.

[Malibyte]

I forgot to mention. Make sure that you bypass the stock J tube on the side of the engine. I assume you already have, but if you have not, please do so. That will make it easier to lower your fuel pressure and should help the overrich in the top end.

Robert:

That J-tube was never drilled out in the first place, so it hasn't been a factor.

OK, ran around on the freeway this afternoon with the laptop hooked up...because of traffic concerns I wasn't really able to tromp on it as much as I would have liked...dropping the pressure helped a bit, but I'm still rich, even with he S-AFC down 20-21% at 4-6K; at 15.5 pounds of boost and only about 88-90% of WOT, it still bottoms out around 10.5-10.7 (it had been as bad as 9.8). I really am not too comfortable leaning it out too much more with the S-AFC. Anyone have any other ideas???

I have noticed better gas mileage, though. :)

Bob

[Junkie]

That J-tube was never drilled out in the first place, so it hasn't been a factor.



Bob,you say not drilled out.... is it still being used ? If so,bypass it,then check FP.

[Malibyte]

Bob,you say not drilled out.... is it still being used ? If so,bypass it,then check FP.


Shawn - no, it's not being used.

[Junkie]

Cool,just a bit confused with the last post,but that's probably the fog I'm in ;)

IIRC,we have O's s-afc leaned 20-25% above 3500ish.Car isn't here for me to check,"wow,4 months no repairs :) " but,I'll check it out when I get a chance.

Give it another 1% at a time.I know at one time we had it at 25%+.When the 780's were installed,we were leaning out 40%+,running 11.2-11.7 AFR

[Malibyte]

Shawn....thanks, definitely appreciate it. You know how it is....gotta tune it just right...but I don't want to grenade the damn thing in the process!!

[935motorsports]

Well tuning by internet is never a good thing, but we try.

The problem we have with Bob's car is, Lex, and leaning it out still. We only get 91 pump gas, so we have to be careful. He does not have a shaved block, that is good. He does have a shaved head, so that did bump the compression slightly. How much he can pull from the SAFC is directly related to the final boost figure he wants to run.

I'd rather see him run rich, then pulling the engine out from a cracked piston. I would personally go a bit leaner, but I can't suggest that, then have him posting that something went wrong.

I've seen 2 cali 7mgtes BLOW a piston at the dyno, at just a simple -25% SAFC lean. That is why I'm so nervous about it.

I would rather know why he can't lower the fuel pressure anymore. I just setup a MK3 with 780s, and our lowest fuel pressure is 15 psi base.

If he was to stay at 15/16 psi max, then we can get a little more aggressive. The fun begins at 18 psi though :). Unfortunately that is where the CT starts to choke.

Lots of decisions have to be made, a crossroads is coming up. But like I said, I wonder why you can't lower the pressure any more, that is odd.

[Moorman]

I'd rather see him run rich, then pulling the engine out from a cracked piston.

Are you poking my wound? Is that fingertip salty with a hint of lemon? :wtf:

.....bastardguy.



[/narcissistic indulgence]