I know a couple blokes around my area who have the potential to chip my good old TJ Exec, but my only issue is what exactly gets "chipped?"

As always, here's my list of n00b questions which would be greatly appreciative of answers :)

- which ECUs in the car get chipped?

- what's the highest reasonable gain in performance?

- is it true that the VRX is chipped up to 163Kw stock?

- if anyone has he patience, could someone please explain which dynamics of the car are changed from he ECU flash? Are certain restrictions lifted? Is the flow of fluids altered? Or is there simply one computer in the car and ECUs are completely different?

I'm sorry if such questions are stupid enough to frustrate some of you guys on here, but I believe getting a tune is a good bang for your buck upgrade :)

Cheers!

fuel and ignition maps get changed basically. yes the vrx has 163kw, the main ecu is the one thats altered. not chipped as such, gains can vary depending on cams exhaust etc.

i dont think the vrx ecu is any different to an exec.

fuel and ignition maps get changed basically. yes the vrx has 163kw, the main ecu is the one thats altered. not chipped as such, gains can vary depending on cams exhaust etc.

Oh okay so it is all to do with the fuel and ignition coupled with the gear of your car. I've already got a great exhaust system, but I'm still running the stock cam, any recommendations?

- which ECUs in the car get chipped?

It depends what you mean by "chipped"... it could mean an interceptor (aka piggyback) ECU or modifying the mapping in the stock ECU. Your TJ has a reflashable ECU, and the equipment to reflash it is readily available (and relatively inexpensive if you already have a Windows notebook). See the thread linked in my signature for more information about reflashing the stock ECU.


- what's the highest reasonable gain in performance?

From what I've seen and been told, going to a 98RON tune from the stock 91RON tune would probably get a 4-6kW gain at peak output, however you're likely to get slightly better gains lower in the rev range which improve drivability noticeably. You won't get much by trying to tune on 91RON fuel, as the stock tune is not overly conservative.


- is it true that the VRX is chipped up to 163Kw stock?

No. The gain was exclusively the result of a better flowing muffler.

I've already got a great exhaust system, but I'm still running the stock cam, any recommendations?
Ralliart or 380 cams are the most consistent for an automatic. If you're prepared to do the work yourself, fitting adjustable cam gears (can be had from the US for around $250) and adding some advance to the camshaft timing helps, even with the stock #6 cams (though the gains were modest, drivability improved and I found the exhaust note had a mild crackle on over-run when I tried this).

No. The gain was exclusively the result of a better flowing muffler.

Wow, so an 8Kw gain from the 155 stock was achieved with just a better flowing muffler? :O
I have a Lukey, hi-flow cat and pacemakers attached to my baby, what's that put my gain at?

Wow, so an 8Kw gain from the 155 stock was achieved with just a better flowing muffler? :O
I have a Lukey, hi-flow cat and pacemakers attached to my baby, what's that put my gain at?

Probably 165 due to power loss from the years, at a guess

If you are chasing more power and looking at flashing the ECU, then you should get some ralliart or 380 cams and put a ralliart tune on the car. Should make plenty of power.