IAT timing tricker for nirtous...
 

Can anyone send me a diagram on how to do this??... Something like a 750ohm resistor or something.... I have a zo6 maf so I have the 5 wire MAF... I need to know what color wires do what on the IAT wiring on the MAF... Here is a diagram I found can someone elaborate on it....

http://ls1tech.com/forums/attachment...chmentid=21043

From what it says put power to point C...ok how's that work a 2 pole switch??? from the batt. to one pole then the other pole to the "point C" on the diagram????

Also wires A & B that come from the pcm... what color wire (meaning POINT B) goes to the relay??



Thanks.....

Anyone.....????:smash: :bigears

Do a search over at tech, this was a resent topic. I can't remember myself, it's been a few years since messing with this.
Robert

I tried, but couldent find which wires on the IAT sensor do what...

Check back in a bit to the diagram over at tech, I will post the info I have on what pinout from the pcm connectors. from there you have to use an ohm meter to verify at the IAT. I only have certain years info, so...
Robert

Where should I look at ls1tech...nitrous section??? could you e-mail it to me?? Pm sent..

Yes, n2o section, the wiring sticky at the top of page, and post #112. I have some other info and diagrams on this type of trick, and think it's on the 2nd page towards the bottom, but post # not sure.
Robert

Robert, when I put the 750ohm resistor in and it tricks the IAT sensor into thinking xxx*f can I go into my efilive table IAT vs. Spark and change the value to pull say 8* of timing insted of it only pulling 3-4* of timing..??

BTW. I have Efilive

Robert, it says put power to point C.... what kind of power, 12v switched source or from the battery.. also what king of switch??? (i.e.)2 pole?? :thumbs:

BTW, the color wires are correct for all years. I just looked at the car (01 z06) and thoes were the ones....

What are you trying to accomplish by doing this?

If you don't want the pcm to pull timing due to high IAT's, just edit your tune or get a 2 pin iat sensor and stick it in the nose of the car where the ambient sensor is, in front of the rad.

Yes just a toggle switch with a 12v supply. It only takes milla amps to activate the relay to switch to the resistor. ya EFI live has a Cos 5 for Nitrous. Check with Beer, he is running it and has a great timing pull set up. As for changing the amount in your program, yes as long as it's a temp you wont see n/a, or n/a you'll pill the amount you enter if ya hiot that temp.
Robert

Pulling timing while spraying only.
Robert

If he wants to pull while spraying, then wouldn't IAT's go down when spraying? He could edit his tune to pull below a certain temp...just a thought.

I sprayed a 175 shot on my silverado and never had to pull any...:willy: (only did that for 2 years though)

Otherwise, if it's the same setup as an 03 Z maf, then wires to iat are purple and tan. purple is ref and tan is iat signal

You could use the same circuit as used to activate the nos. For example, it you are running the ground thru a wot switch at floor, then use that ground to energize the relay. In which case, 'C' would have to be hot already.

Ok, but a 2 pole switch??? Power into the switch, then power comming out of the switch, going to "point C" on the relay???

Thanks, Id rather do it this way (no COS)... I had this on the car years ago, but I didnt wire it, cartek did... It was set to see 130* IAT temps, verifyied by my diablo programmer... Like I said years ago... Only downfall to this as I remember it took a couple of seconds to trick the sensor, once again verifyied by my diablo programmer.. I watched the IAT sensor go to 130* and I was good to go....

So ill do this for my street nitrous kit, and the DP will be strictly in the tune...:thumbs:

No sir, wet kit into the TB

Ok, so if your wires are tan and purple, then according to your diagram of the relay, purple is A and tan is B and goes through the relay.

when relay is NOT on, pcm sees resistance from iat. When relay IS on, pcm sees 750 ohms resistance, which will corrsepond to a certain temp...perhaps 130F.

Thats the idea boss...

EXCEPT..... reverse what you said..

Tan would be "A"
Purple would be "B"

Tan = signal "A"
Purple = ground "B"

You want to use a 1k ohm resister.This will read 140-145 degree's.
2 pole toggle switch or a 2 pole relay which works better. I use the relay to switch from the sensor to the resister only when the Nitrous is armed (or solinoid is spraying) .This way you can tune the IAT table at 140 degree's to pull whatever timing you want. Very reliable and have had cars hooked up for years like that.:)

cool, slowhawk... does the diagram look right to you??? OR could you show me/us youre wiring diagram with a 2 pole relay???

thanks

I think opposite, but it's your nickel..:eek: (why would you run the purple gnd wire through resistor ?)

One small thought....

You have a choice as to how to use the relay to trick the pcm, and the relay should last forever (or almost).

I would personally make it so the relay has to be OFF rather than ON to pull timing.

Why?

Because wiring it as per your diagram could make the engine go KABOOM :eek: :willy: , should the relay or wiring to it ever have a problem while you're on the juice.

Only downfall, is relay may wear out prematurely ..better a burnt relay than a burnt engine.

My 2 cents.

:cheers:

Yes,that is the way I would do it.Just make sure your wiring is tight.As said before we have a few very expensive setup's running this method without any failures. 1 car has had this for 4 years and still working strong.

Yes a relay can fail,but so can an injector.Thats life;)

Is there a way to wire it without a relay???:bigears ... If I remember thats how cartek did mine a few years ago...

That is just BAD advice.:nono:

Yes, most people wire it like that , but it's easy to give bad advice when it's NOT your car or money at stake.

Ok , you choose

Wire it to turn on the relay in order to pull timing and IF the relay fails, your motor may go Kaboom.

or

Wire it the other way and worse case scenario, if the relay fails, you run with timing retard.

Your choice, your car, your money...

Be my guest.

In industry, i design circuits all the time on machines that can cause loss of limb or life. We ALWAYS wire relays such that failure of anything and the machine doesn't move and no one gets hurt.

This is not as critical, it's only money, but how will you feel if the relay fails, the engine goes south and THEN someone asks why you didn't wire it the other way.

Bad advice IMO...:leaving:

Wow buddy, easy there.

Slowhawk is a smart guy and has been around for a while and has done a bunch of cars with great success. Is your way better? Possibly. But to go and just say that his advice is BAD is a bit abrassive, don't you think?

And don't think for one moment that it's easy to give "bad" advice when it's not your money or your car. After all, it's his reputation that's on the line -- which is substantially more valuable.

With the low failure rate of relays, and the ability of our LS motors to absorb detonation without dying immediately (thank you knock retard!), is it really worth it to call someone out like that and say his advice is bad? :crazy:

It's not personal, it's just bad advice. Do we all need to pad our opinions on this forum? If that's the case, then someone please pm me to that effect.

There's an old saying that goes something like this

"that's the way we've been doing it forever' that 's a sure sign that change is possibly needed.

I am sure that Slowhawk has done 10 thousand times more work on cars than me, and from he little that I've seen it looks great, but I may just be a little more meticulous in some areas...or paranoid.

Mis-information on forums like this runs rampant. someone has to speak up sometimes, especialy when the cost to do it either way is the same oo of negligible difference.

Go ahead, blow me out of the water, I can take it.

when i give bad advice, I hope someone corrects me.

:cheers:

btw: Why not just discuss or argue the point? Maybe I'll see it his way..:thumbs: If anyone thinks that taking a chance on your timing being slightly retarded vs your engine going south is not worth mentioning , then let me know why.

I didn't say it wasn't worth mentioning, but saying it is bad advice is overboard and sort of like saying that running 13 degrees of timing on a given car instead of 12 degrees of timing is bad advice, when it will actually take 15 degrees without detonating.

Yeah, 13 degrees makes it more likely to have a problem, but that likelihood is real low, yes?

Don't worry Diynoob, RJW has a habit of trolling me lately;)

In case you want to know I'm also a control Electrician so I know what can happen.Always open for opinions but going as far as bad advise? Spend some more time doing this stuff which will get you off the first grade of car mechanics and then you can throw stupid remarks out:thumbs:

If you're are actually qualified in that area, then it must be your big ego that caused you to dismiss what I said to the orignal poster as not worth a response, which is OK in that many who own or work with vettes are prima donnas.

Again your ego has passed judgement on my mechanical qualifications. While I have been out of this business for a while, I've been known to hold my own with the BEST and since the early 70's.

I think that you are riding a little high on your 'rep' and have forgotten your roots a little.

Have a nice day...Don't worry, I won't 'troll' you anymore, and you can continue to mock my RED blower, cause you're 'Slowhawk'. oh my god..:willy: :rofl: :rofl: :rofl:

or you could simply agree or discuss my relay related point and rather than flex our egos, we could help enlighten some people and share knowledge.

Your choice,...

Hey no BS RJW... Its my thread and im open to all suggestions...

ONCE AGAIN, CAN IT BE DONE WITHOUT A RELAY???

RJW, If you wire it youre way, worst case senario run with timing retard??? elaborate please

Ok

Conventional method:

If you wire it so that the relay comes ON with either a switch or thru your NOS setup, then if the relay FAILS, then it won't come on and NO timing will be pulled. Possible engine damage from too much timing due to FAILED relay.

My suggestion:

If you wire it so that the relay is always on until you hit the swtich or NOS controller kicks in, then the relay shuts off and timing is pulled.

With this method, if the relay FAILS, then you will be driving around with timing retard ALL the time, but at least the failure will not possibly cause damage to your engine.

If you pull enough timing, you should notice when NOT on the bottle, that your car is down on power due to timing retard from FAILED relay and you correct the problem. AT least your engine is still intact.

Only if the relay contacts weld to each other would timing not be pulled when on the bottle.

As far as running without relay, we need to see a diagram of how your system is setup.

Or, perhaps Slowhawk can chime in and take over, in that he seems to be a resident expert., and I hope that he will not abandon you just because we had a small spat.

Slowhawk? How about it?

So could you draw me a diagram just like the one I posted.. and wire it the way you said.. It would help me alot since iam not a wiring person. I have an auto Im gonna use a push button to activate the system (i.e.the telephone cord style push button) and have a seperate switch to control the IAT timing tricker...


Its not the best way but it works and ive had luck with it in the past.. So could you help a brother out??? with a wiring diagram...

and NAH, slowhawk is a cool dude.. he's just a m******* like me:lol:

If you are going to use a switch for the IAT, then get a single pole double throw switch and forget the relay. The switch should have 3 pins (terminals) and should only have 2 positions, like up and down, NO center position.

Here's how to wire it. The switch has 3 pins, one in the center and 2 others near the ends of the switch.

From your relay diagram, hook the pcm wire ( relay pin 30) to the center terminal, the wire with resistor (relay pin 87) to one of the other pins on the switch and the last wire (relay pin 87a) to the remaining pin on the switch.

Start the car and use your tuning software to check IAT. Flip the switch and it should change.

Just make sure that you mount the switch so that youknow which position is which

Good luck with it...let us know how you make out. Forget the relay, but don't forget to hit the swtich!

The reason I do it off a relay is to make it idiot proof.The relay is hooked up to only retard timing when the system sprays. We do this because alot of customers launch without spray and want 100% timing then everytime the nitrous solinoid gets power the relay switches and pulls timing. It's no big deal and if it's wired right you will not have a problem.I don't like the failed power/retarded power method.

I do not like a switch because that can be forgotten which it probly will when someone is in a rush to spray.

If the car is setup with a small 100 shot or less you just take 2 degree's of timing out of the tune and not worry about it since minimum NA hp is lost. A relay should be used for 150+ shot.

cool... thanks

So, this is how to wire it WITHOUT a relay... just to make sense....

Excuse me for being ignorant, BUT I still dont understand fully..I kinda do, but dont.. Just want to be 100% sure I do it correct

I need a diagram, or its hard for me to read it.. iam the type who needs to see a pic to understand it.

THANKS

Thanks as well don....

Can some pls post a few pics of this pls?

A couple other options. Instead of a fixed value resistor, you can set it up with a Potentiometer, which is variable resistance rheostat, this way you can dial in different amounts of timing pull, depending on which temps you go to and what you have selected to pull at that temp. Very usefull for those that run multi stage, or who change the size of hit.

Another area to be addressed, is the slow response time, prob the biggest draw back to using this method (because you want your pull at your most vunerable spray time, which is activation point where your torque sky rockets and produces the highest cylinder pressures and potential damage). So, a way around this is to use a dedicated window switch or a rpm activation sw. You can have it set up to switch to timing pull at a rpm lower than your n2o activation point. that way, you get the timing pull, pulling right before n2o sprays, and bingo, timing pull at activation, no hesiatation and safe for your mega torque spike.

You can also use a pot on a old style pill WS, like the MSD unit. The pills are just resistors, so you can also dial in the exact rpm for spraying, or for the above trick. yes, you should have a fairly good understanding of wiring and the such, but all tips/tricks are doable if ya want to put the effort out. :flag:

Now if going dry hit, it's mucho easier, but that's another story. :thumbs:

Sorry if I totally confused you. There is one other wiring diagram for timing pull that I posted at tech in the sticky, maybe more insight?

Robert

Yes, you can use a DPDT toggle switch, one side of the switch is used to activate the nitrous and the other for the IAT mod, or a SPDT switch and just wire the IAT circuit.

I actually did this on some Northstar powered Cadies with nitrous before the LS1s were out back in 1996, and naturally started doing it on LS1s. It works really well and combined with tuning you can tailor exactly how much timing to retard. The response time is much quicker than you might think, the reason it takes long to show up on some scanners is that the sampling rate is slow. I now usually wire it with a relay so when the nitrous actually activates (when the solenoids turn on) the retard takes place, that way there is full timing during launch until the nitrous turns on and then retards, doing it this way the 60' won't suffer if the nitrous turns on at a higher RPM than your converter stall.


HTH, Julio

Just keep in mind that a high quality potentiometer would have to be used. Most purchased at local electronic stores probably won't be up to the task, I would use a mil or industrial spec pot. The wipers get dirty and could change resistance or completely open over time from the set point with vibration and extreme temperature changes. This is why I prefer a fixed resistor and make the changes with the tuning software in the IAT tables.


Julio

Julio to the rescue......:eek: :)

Agreed, great advice. :thumbs:
Robert

Ive got it hooked up.. will i notice a differnce when the car is on.
 

Im going to test the system to see if it pulls the timing. Im turning on my nitrous system at idel to see if the cars timing will get pulled when there is power fed to the relay. Should i notice a differnce??

i heard if you have a 1997 or 1998 you can use a 4.5 ohm resistor, unplug the weather pack from the iat sensor connection and put the resistor leads into the pcm side of the connector and wrap it with electrical tape and this gains around 10 hp. Is this tru ???