Buying a truck with the TRD Supercharger

[CA-RJ]

It looks like I will taking a road trip to look at a 2003 Double Cab TRD with the Supercharger installed. The owner says the SC was installed 15k miles ago and that it has a URD Split Second FTC and URD Fuel Ratio Calibrator installed. When looking at the the SC, is there anything I should be looking for to make sure it's functioning correctly and installed right?

 

[fourfa]

ask if you can pull the spark plugs to read their color

 

[J-man]

see who did the install & tuning, and if you can see any dyno sheets showing what the AFR's / hp#s are - i would go as far as taking a wideband meter with you to check the afr's when you test drive it - that way you'll know if the motor is running lean or not.

 

[CA-RJ]

I'm embarrassed to say that I do not know what you are talking about. I'll see if it's been tuned. Probably a stupid question, but can I take it in to a local Toyota dealership to see if it's been installed correctly? Should I just look at another truck if I don't know what I'm looking at?

 

[J-man]

Buying a truck with the supercharger + all the URD goodies can be a great buy, but the URD kit for the supercharger replaces all the injectors and has a piggyback computer that is spliced into the factory wiring harness thus taking over the stock toyota computer. Whenever you go forced induction, (pumping more air into the motor) you have to pump more fuel and adress timing as well.

Questions to ask are: Who installed the URD kit? How much boost - stock 7lbs, or the smaller pully which takes it to 9-10 lbs? Find out all other modifications done to the motor. Was there ever any water injection? Is it the complete kit with 318 injectors, FTC, cooler plugs, new fuel pump, cooler t-stat, etc..heres a link to the kit: http://www.urdusa.com/product_info.php?cPath=79_80&products_id=1230100017

It is essential to know how it was tuned, on the dyno or the street, and to know what the AFR's are (air/fuel ratios) as that tells you if the motor is running lean or rich. A little rich is okay, but if its lean its safe to say that cracked heads are a possibility now, or in the short future.

Being that you dont know much about the supercharger for the 3.4, go over to customtacos.com and start reading up. It can be a great addition to your truck, but if you are not ready for quirky things and be able to solve them yourself, then you might want to think about not getting that truck. It can be the biggest pain in your ***** when things start going wrong so be prepared to learn.

 

[J-man]

and no, if you take it into a stealership, they will point their finger to the exit and tell you to leave. The only thing toyota is the supercharger itself which most dealers become glassy eyed as they know nothing about them, but more so they have no idea how the URD kit works and wont touch a truck with a 5 ft pole that has it installed.

 

[109 Pretender]

As the OP said it's a TRD s/c w/URD add-ons, I would be most interested if it was owned by an adult or youngster who has full control of their right foot or not...

The TRD kit is very good and the URD enhancements are good too. If everything was done correctly you shouldn't have any problems and 2003 model shouldn't have too many miles racked up yet. I'd stay away if you 'suspect' owner was a lead foot or if it runs 'funny' at all.

Owner might allow you to take it to a mech to scan for codes and give it a general look over - your dime of course.

I'd recommend you drive it and compare to a stock Taco and see if you like the differences in power and complexity or not.

I think the 3.4 s/c wasn't as well developed as the s/c for the 4.0 engine - but a lot of people have done it to their Tacos and had good luck.

One more note - you will have to run the best premium gas generally available (91 -93 octane min.). Otherwise the engine will be prone to detonation - which is as bad as it sounds...

Good Luck!

 

[CA-RJ]

From an email I received this morning.

I personally installed it. I'm a jet engine control system engineer so I was very particular in tuning it, took me about a year before I was happy. I have had it up to 14k feet and the AFR runs around 13 in boost and the EGT stay under 1450. I haven't touched the tune for the last 9 months. I did the tuning using a LM-2 from Innovate Motorsports. I have data I can get to you later today. I learned a lot from this exercise that is not written anywhere on the web or listed on Gadget's website for tuning.

and

Attached are the files I used during tuning. Fuel Trims Rev22 is the the currently loaded tune I have been running. I used the LM-2 to log data for long periods of time then used a macro to create an average of the Toyota ECU short and long term trims. I then used these numbers to offset the engine trims using the URD controller. Then I logged more data and used the average and std dev to fine tune the values. Then I made some long pulls up the mtns to Flagstaff to ensure I had all the corner points correct. I hand tuned these by reviewing the data logged by the LM-2 and URD controller. The last step was the most difficult, idle tuning is a mix of open and closed loop control loops. I found no information of the web about this but I discovered that the Toyota ECU will apply an offset to the entire map if the long term trim at idle exceeds a threshold. Once I determined this function I was able to complete the tune.

There are 2 files he sent me. One I can't view because it's from the software he used to tune it and the other appears to be fuel trim data.

Thoughts?

 

[java]

well it sounds like he knows what he is talking about. can you post the data log files?

 

[J-man]

13 afr's are too lean for these motors under boost. It should be 11.8 - 12. However it does sound like he knows how to tune it, just needs to richen it up a little. Why is he selling? Tired of constant tuning issues / quirks? Ask him.

 

[Wheelingnoob]

13afr is lean on that engine or any boosted motor. Ideal is 11.7-12AFR as a rule of thumb. If you are still interested in this truck or any boosted car/truck take it to a shop and have them perform a leak down test on the engine. This will give you an over all condition of the engine and highlight any problems.

Also when you test drive it do not be shy open it up with the windows closed and the fan and radio off, listen for detonation. best way I have found to get det if its going to happen has been to cruse at about 30mph and hit the gas all the way this will load up the engine usually show det if there is going to be any.

One last thing to do is ask him what grade of fuel he uses and look for any fuel receipts in the truck that will show the grade of gas.

It sounds like he knows what he is doing with the tuning, if it all checks out fine maybe ask if he will tune it to a bit more conservative AFR (11.5-12.0) before you take it.

Good luck.

p.s. I do not have a S/C truck but I have lived and worked around boosted cars for the last 15 years.