Does everyone who has done the DIY VB mod still recommend it? I'm thinking about replacing my ATF for maintenance reasons and I figure I could use that as a excuse to do the mod.
Any feedback would be greatly appreciated! Thanks everyone.

 

why do the VB mod on a n/a truck?

 

So you zeroed out the timing map that was loaded in the AIC-T from URD? If not then your not pinging because of the timing map already in the box as default.

My truck pinged pretty bad in some placed even WITH the URD map. I had to take as much as 6 degrees away in some places. However I did tune mine in a worst case scenario in 110 degree heat and 60% humidity.

 

I'm pulling 6 degrees too, I've tried to go more than that but it immediately throws flashing CELs for misfires with anything more than 6 in a cell.

 

The guy who did it over on CT did it to his n/a 2.7lt and was impressed with the over all improvements. I think I would like to see the improvements the n/a 3.4lt has to offer. Plus when I can afford it I plan on putting the TRD blower on my truck. I kind of want to see how the transmission acts in stages.

1. Temp completely stock
2. Temp w/ VB upgrade
3. Temp w/ SC + VB upgrade

I'm always interested in cutting down how quick my truck can make it to 75mph.

 

Originally Posted by mt_goat:
Ok Bro, hooked up the lap top and tools today and did a video of my closed loop AFR and output shown on the OBD-II BR-3. Sure enough I'm in CLOSED LOOP at 13.5 AFR. My fuel trims are better than I thought to boot!!

 

Cool, thanks Speedy.

 

I haven't touched the maps that came loaded. The timing map seems to be just about right. I don't know if its because I have a stick or what, but so far everything seems to be pretty good with the delivered maps. AFR and timing seem good. But I guess its hard to really tell about the knock without probing the knock sensor. All audible ping is gone with the stock timing map. I think I can actually remove some of the timing retard on my setup. I'll keep you posted....

 

Ah, OK. I thought you were saying your truck didn't ping at all, even without the timing pulled by the AIC-T. If you can get by with less timing retard then go for it. Just be sure.

 

Hey Speedy, can you give a quick overview of what the long term and short term trims are? Why is one positive and one negative? How many miles do you need to drive before they give good readings since the last battery disconnect?
thanks in advance.

 

100 - 200 miles should be enough for the computer to re-learn trims.

Short term fuel trims are based on temporary conditions the vehicle is seeing like air temp etc. Long term trims are based on over all vehicle conditions for a longer period of time (100 - 200 miles I'd say). A positive number means the vehicle's ECU read a lean condition and is adding fuel to the base fuel map to get to it's proper AFR. A negative number means the vehicle's ECU is reading rich and is subtracting fuel from the base fuel map to get to the proper AFR.

You want them to get as close to zeroing each other out as possible. It'll never be perfect because it's dynamic, but I've read in several places getting the final number below 10 is pretty good. Understand that you add the long term and short term together to get the final fuel trim number. So say you had a -3 in short term and a 9 in the long term. Then your total is 6.

Basically what you're trying to do is keep the computer from making adjustments at all. The closer you get this to zero the less adjusting the computer is doing to the base fuel map and makes for a better running motor.

 

thanks for the info speedy. I have hooked up the AFR sensor, R4 software, OBD2, and camstudio and have gone and done some test runs. I found that my fuel trims are always less than +-5 amazingly using the delivered URD maps. The URD maps seems to be damn good on my truck. I am a little rich in open loop at all boost levels at 3500RPM under heavy load, but I am about to start tweeking that out.

I have one question though. When you upload the new maps, are you using "additional injector controller or the other setting in the R4 SW? And are you using 3 cylinder 2 stroke? I am not sure which system settings to use but I assume those are the correct ones.

thanks in advance.

 

Gadget's 7th Injector U-Tune Guide has instructions on how to set up the software, but yes it's 3 cylinder 2 stroke and Additional Injector Controller.

Edited to add, make sure to keep backups of your map once done, or in stages. That way if you get it all fubared, you have something to go back to. I'd also like to see some of your tuning video when done.

 

For the URD AIC units, for the 5vz use 3 cyl 2 stroke for the engine settings. This will cause the injector to be cycled 3 time a revolution of the engine to match the number of intake events and provides the most even fuel distribution.

For all the other products that use the R4 tunings software, use 6 cyl 4 stoke for the 5vz.

There is more info on the proper settings for the URD AIC units here:

www.GadgetOnline.com/u-tune-aic.pdf


Gadget

 

whats the best place to upload my movie? photo bucket? youtube? I like how I can watch it in slower motion using windows media player, not sure you can do that if its hosted on a web server. I took one on the way to work today going up a steep hill in boost for over 30secs straight at all boost levels with the engine at 90%+ load. You should check it out...

 

How big is it? You can use a program called Virtual Dub (free) to edit it down.

If it's small enough just e-mail it to me.

 

click full size in the upper left corner of the video. Video is large so be patient.

This was going up a steep hill on the freeway going 70-80MPH. I drive a 5speed so when things go funky its during an up or down 4th-5th gear change or letting up to avoid rear ending someone. URD stock maps timing and AIC map with AFR hardcoded, 2.2 pully.

http://s114.photobucket.com/albums/n...rent=dsdd4.flv

 

I did some more test runs tonight and found that I am running 10-11 in open loop in all the areas where I would actually drive (under 5000RPMS at any boost) with most of my cells set to 1.1 or 1.2. Looks like I don't need my 7th injector or the fuel pump. I hadn't even put the fuel pump in. The timing and AFR adjuster were the only upgrades my truck really needs even with the 2.2 pulley.

I'll do some more testing, but it looks like the 7th will probably be coming off and getting sold with the fuel pump...

 

You may want to give the system more time to settle down. I ran very rich at first too, but after about 3 weeks I noticed it lean back up especially after getting my timing tuned properly. I modified the URD timing map quite a bit. After tuning on the dyno and road tuning, I found I definitely needed the 7th from 4500 RPM up. Also, the 7th will give some intercooling effect which aids to reduce ping.

Also, if timing is retarded too much it'll lower your AFRs ALOT. I noticed after 5-6 full throttle runs I'd start seeing AFRs that would normally be in the 11.5 range drop to 10s due to timing retard. I attribute this to the extra heat generated after several WOT runs.

How much max boost are you seeing in the R4 software with the 2.2" pulley? I see a solid 10.5 psi.

Are you at sea level?

I didn't need the Walbro 190 fuel pump in my application, but if I go more than a 2.2" pulley I probably will.

 

speedy, can you send me your timing map again, my outlook blocked it due to unknown file type

Yes I am at sea level, and drive out to the desert weekly where I climb to 4000ft.

I'm seeing 8PSI max. Isn't there a boost limiter on the SC? I haven't touched it if there is one so that could be why I see the same amount of boost with the 2.2 pully. Honestly, I think I only really need 5-6PSI. I don't drive my truck like a drag car.

I bought the truck used with 90K miles with the supercharger on it the whole time. It has 90K miles of SC with no fuel mods etc and it ran good without them, the only thing was it would ping below 3K RPMS. It had a boost gauge on it and the PO told me he knew it pinged below 3K and would drive in boost always above 3K. I believed him, took a risk and bought the truck. And honestly, it runs great! I don't regret it at all. The reason I bought the 7th kit is because I hear how lean these engines run and the pinging etc, but I think the stock fuel system can keep up on this particular truck. The timing retard seems to be the most important thing. That along with getting and AFR meter on there and knowing what your AFR really is.

I'm going to unplug the 7th and do some logging and see how that looks. I will have to tune the timing still, but not really sure how to do that? Are you guys just using your ear to do timing adjustment?