CAT3

iTrader: (9)

I thought I would have more time, but with our track closed I have to find "alternate" areas for testing.
My original idea was to use a signal off the WOT Switch to activate a relay that cuts the IAT sensor input (this would show -38* once the system was activated, and or armed if you wanted it that way). Then tune the fueling and ignition accoridng to the forecasted temperature. Not sure why I havent messed with it yet, but I need to. Might be because I hate wiring stuff up. I like the type connections that look like factory, which makes me want to order up one of the Metric Pak connector kits, unless I can find some on island.

BTW, anyone using a 2bar MAP with HPT? I am curious to see what exactly it is thats different? Thanks.

Spenser309

some people have tried doing that to get rid of the intitial lean spike on there dry systems, You'd be the first "i think" to go SD Dry. But ill be the first to a Seqential DP SD Dry setup. bwahahaha.

CAT3

iTrader: (9)

Spenser, I was reading your post about hooking that up. I'll be very interested in seeing that setup. I do have some stuff in the works, but I need to get this DSD tune down first....gotta follow thru.

Sport Side

iTrader: (6)

I'm running a SD-Dry at the track.

Here is a picture: Click

I mounted the IAT in the heat shield for my cold air intake.
Here is a picture: Click
The little black nipple is the NAPA purchased IAT sensor.

I'm not sweet like you tho... Never even thought about that relay ****, to knock the IAT readings down.
That's smart.
However, I don't have a PE vs. IAT addition with my PCM. Still a good idea for those who have it and are running SD.

CAT3

iTrader: (9)

Sport Side, how is tune setup for nitrous then if there is no trigger (IAT, xxx MAF etc)? Thanks and nice looking setup.

Charlie

Spenser309

yea, i dont know how that would work unless your just constantly dumping in your nitrous enrichment.

Sport Side

iTrader: (6)

Yep. It's just thru PE. So, it requires dual tunes if you are looking for max NA and N2O performance... That's why I run it at the track only.
This setup hits twice as hard initially as it does when the N2O is entranced at the end of my cold air intake.

I'll actually be sizing down to a .30 jet to stop from spinning.
Both a 75 and 100 shot spun the tires severly when setup like so.

Lrry93

iTrader: (2)

Sport, (this is CAT3), thats how most ppl are running a "dry" SD tune. glad you clarified that for me, thanks. I am not wanting to keep changing tunes, hence the Solenoid-activated IAT Kicker or S.I.K. (marketing tools).

CAT3

iTrader: (9)

Another thing Sport, does the 2001-2002 Truck PCM have the IAT vs..... parameters? If so, then you could be in the same boat as I am, needing to rewrite OS to a 2002.

Sport Side

iTrader: (6)

The 2002... I believe does.
I'm on a 2000 PCM so, mine does not.

I will be using a MAF setup once again. Refabbing tomorrow.

Keep me updated on your process and if you go with that.
One day I may swap PCMs and wire something like this in. It's a great idea.

CAT3

iTrader: (9)

I'll keep ya updated, either by reviving this thread or a new one.

white2001s10

iTrader: (4)

Hardly the first. I was doing it in the mid 90's.
I recently set one up for a friend of mine who will be testing it tomorrow in fact.
It's a typical switched ECT tricker that uses the upper range 248*F to adjust the fuel and spark, but what makes this one a little unique is the first time I've used such a nice potentiometer ($12.49 each) for one.
This baby has 10 full turns of resolution from 0 to 500 ohms, so it should be very nice to use. I ramped the fuel before and after the 248*F mark so it will be a simple matter to fine adjust the temp a little bit for a little more or less fuel. The resolution will just make this easier.
It's part # 502-0102 from MCM electronics if anyone is interested.
If that's out of stock, they have a 0 to 1000 (1K) ohm model that would work well too.

I always use DPDT switches to go between the ECT and the Pot. It can be wired with two relays to work only when the nitrous is activated, but I prefer it on a switch.

CAT3

iTrader: (9)

DPDT switches?

White, much the same thing I have been working on, only using IAT rather than ECT. I figure the ECT might throw out more variables than the IAT tricking, but sounds like maybe not? I still have made little progress, kind of hard since the track is closed I wanted to actually use two resistors, rather than a Pot., having adjustable switch to select from normal IAT sensor activity for Daily Driving, setting 2 being XXX temp and match the fuel and spark for only 1 stage, and then setting 2 for the big shot. Potentiometer and dial sounds groovey too. Actually do you know where to get some nice rotating switches?
Charlie

white2001s10

iTrader: (4)

Radio Shack used to carry decent stuff like that but they hacked most of it from their inventory to make room for Ipods and cellphone crap.
I use mail-order companies anymore like MCM electronics, or Granger or some other electronics warehouse.

Here's the settings that I just did for a friends dry N2O SD tune.
It uses the upper end of the ECT range, and a DPDT toggle to switch between the sensor and the Pot.
I tested it out this evening and it ended up only wanting about 15.5% more fuel (232*F setting) for a .042 jet I think it was.

Here's some info I sent him to print as a tuning reference for using the Pot for fine adjusting for whatever N2O jet or pressure he decides to use.

Spark:
From 131F to 185F your spark stays the same with 0 retard.

194F -0.5*
203F -1.0*
212F -1.5*
221F -2.0*
230F -4.0*
239F -5.0*
248F -5.0*
257F -5.0*
266F -8.0*
275F -8.0*
284F -9.0*
_____________________________________

Fuel:
From 140F to 212F your fueling stays the same with 0% added fuel.

221F +10.0%
230F +15.2%
239F +17.7%
248F +20.0%
257F +25.0%
266F +30.2%
275F +40.0%
284F +50.0%

I gave you the most resolution between 10% and 20% added fuel to take care of the 100 shot. Your total timing will drop from 29* to 24*.
I changed your fan #2 turn-on delay to 30 seconds so you can get through a run without the second fan coming on.
Fan #1 is set to turn off at 30 MPH, so it shouldn't be a problem during a run.

CAT3

iTrader: (9)

Good info. Thanks for sharing. Where did you mount the pot?

white2001s10

iTrader: (4)

The owner mounted it in a fabbed console below the heater control in his C5 vette.

Spenser309

wow, your right. I feel like a complete idiot right now. lol. Should of said the first stock LS1 computer Dry SD, that i have heard of.