FiFdYnUtz

iTrader: (12)

so i am in the process of installing a NX dual nozzle wet kit with HSW microedge and i was reading about doing something with the IAT tables to make it so i can run NA timing when not spraying and less timing when spraying...can anyone elaborate for me or tell me what i need to do. I dont want to have to load a file everytime i want to switch from NA to spray...i am using HPtuners, thanks!

btw i tried to edit my title to RETARD, but i cant, sorry haha.

SkullV

iTrader: (11)

The easiest thing to do would be to run an Interface Air to Fuel controller from HSW as well. This will take care of the IAT tricker part and also has a bunch of other great features.

gametech

iTrader: (1)

You could ground your IAT sensor when the nitrous is armed, while running a tune that retards timing when the IAT is grounded. However, since you are running a wet shot, what about using a separate fuel ssytem for the nos shot? Some VP117 or pure methanol would go a long way toward not knocking.

FiFdYnUtz

iTrader: (12)

i still dont think i could pull off a 150 shot with stock timing and 110+ fuel...and the interface only pulls 3 degrees, im looking to pull around 6..

rickou812

iTrader: (10)

I have been thinking about this same issue, and this is what I am planning to do.
I will use the ground method of the IAT sensor, but with a twist.
I plan on using different resistors wired to a switch that will activate when the N2o/fuel solenoid activates.

I can find the value of the needed resistor by hooking my scanner up and use trial and error until I find the values I need.
I will really only need one resistor, maybe two if I go with a 2 stage.

I will use a rotary type switch:
Say position 1 = off/ no timing pulled
2 = resistor 1 / -4 deg. for 100 shot
3 = resistor 2 / -6 deg for 150 shot
4 = full ground / -12 deg for 250 shot

What I would need to find out is what value resistor I would need to hit a certain area on the IAT vs Kpa Map.
Say resistor #1 would hit 70 C, then I would change the values in the 70c to pull 4 deg of timing.
So on and so forth.

Hopefully I did not confuse anyone, but this is what I'm going to try..

wajouba

iTrader: (1)

If I want to learn how to retard timing on an engine where should I go...? I know the concept I just don't know how... thanks...
sorry for Hijacking

FiFdYnUtz

iTrader: (12)

bump...wajouba search.

ND2RACE

Casper's Electronics makes an IAT interface that works exactly this way, then you just modify your IAT vs timing table to pull as much timing as you want for all the settings.

What I was doing before I set-up a COS was just unplugging the IAT sensor when I wanted to spray. This pegs the IAT to it's coldest setting in the computer and then I just modified the bottom couple lines of the table with the timing retard I wanted. You could set-up something a little nicer, but this works fine for starters.

FiFdYnUtz

iTrader: (12)

^ could you elaborate more on how to do this? my former GTP tuner guy did this on my l67, except it added timing for race gas...

ND2RACE

In whatever tuning software you use you will find a table that modifies the ignition timing based on intake air temp. This table needs to be recalibrated so that it pulls timing based on the IAT sensor. You could simply unplug the sensor causing the computer to see "max cold" IAT temps, so you'd just have to modify that line in the table. If you wanted to have multiple settings you could install a multi-position switch and set-up multiple resistors and scanning to see where in the table you'd be and setting it up accordingly. In my opinion simply buying this part from Casper's Electronics would be much easier and worth the cost. It would be just a matter of tuning the table to control your timing retard how you want. Here is the part:
http://www.casperselectronics.com/st...roducts_id=701

FiFdYnUtz

iTrader: (12)

^ for that kind of money i would likely just get the "timing tuner" that hooks up to the crank sensor and retards timing when nitrous is activated..

where you happy with the iat trick? did it work properly/well? i may go this route for financial sake for now...

FiFdYnUtz

iTrader: (12)

is this the table i should be looking at? and would i add my correction at the TOP because thats coldest? sorry for all the questions, these tables are new to me...thanks for the help so far!

FiFdYnUtz

iTrader: (12)

buump?

East Coast Supercharging

I would personally go with a timing retarder like LPE makes, much cleaner, and more precise.

FiFdYnUtz

iTrader: (12)

so using a $200+ tuner or a half assed iat trick are my ONLY options? damn...

ND2RACE

The IAT trick works fine, like I said I would just unplug it.
Yes that's the table, and I use EFIlive but yes it'd be the colder areas. Test it by datalogging your final timing with and without the IAT trick to make sure you're pulling timing.
Considering I already have the tuning software, the IAT was free by just unplugging it. Then I'd just switch the tune if I'd put in different jets. Those timing tuners are nice, but from what I understand there is no way of knowing if they're actually working. If you datalog, it will still be commanding full timing and you won't actually see the timing pulled, it's just a different type of trick. Depends on how you want it to work, if you don't do your own tuning then paying someone to set-up a multiple retard switch like the one I previously posted is what I'd do. Just my 2 cents.

Goldfinger911

iTrader: (24)

The IAT rewire is easy and works well. You should use relays to alter the sensor path. Here is the resistance data for the IAT sensor. Then you just alter the desired row in the IAT-Timing table. Just be sure to wire it such that the sensor itself is totally out of the circuit when you want to pull timing, otherwise your resistance will vary with temp both ways.

9420 ohms = 32 *F - 0 *C
7280 ohms = 41 *F - 5 *C
5670 ohms = 50 *F - 10 *C
4450 ohms = 59 *F - 15 *C
3520 ohms = 68 *F - 20 *C
2796 ohms = 77 *F - 25 *C
2238 ohms = 86 *F - 30 *C
1802 ohms = 95 *F - 35 *C
1459 ohms = 104 *F - 40 *C
1188 ohms = 113 *F - 45 *C
973 ohms = 122 *F - 50 *C
667 ohms = 140 *F - 60 *C
467 ohms = 158 *F - 70 *C
332 ohms = 176 *F - 80 *C
241 ohms = 194 *F - 90 *C
177 ohms = 212 *F - 100 *C
132 ohms = 230 *F - 110 *C
100 ohms = 248 *F - 120 *C
77 ohms = 266 *F - 130 *C
60 ohms = 284 *F - 140 *C
47 ohms = 302 *F - 150 *

rickou812

iTrader: (10)

Now that is a great informative post

Thanks,
Rick

FiFdYnUtz

iTrader: (12)

damn i wish there wasnt 11in of snow on the ground so i could go try this out!

imola740i

i spray 150on pump gas with zero knock. hold up.....i aint talkin audible, i had laptop hooked up,i know its an iroc but i aint that redneck. the l98 tpi loved full timing too and i sprayed it 200 for years without trouble. i know its against the "prefered methods" but so is adultry.