I've been searching for a while and I can't seem to find a concrete answer. I want to buy a Pettit ecu and am finally thinking that a used one would probably be best because its almost half the price.

I want to know how this ecu works. It says on the website that you can buy 50 dollar chips for the mods that you run. The ecu i'm looking into buying from a member is an "unlimited chip". I've asked the member what that does and he was unsure because he wasn't the original owner.

Also, he said it runs 14.7 psi, i'd want to run closer to 12psi to be safer, Is it possible to change the boost on this ecu just by buying a chip for my mods. And is the unlimited chip one of those 50 dollar chips sold by pettit for an already pettit modified ecu.

sorry for the long post, in short, How does this thing work??

 

The $50 Unlimited Chip goes with the $700 ECU. So, you can't just buy the $50 chip by itself and be done with it. Of course, you are looking at a used Pettit ECU, so it's not $700.

The Pettit Limited chip has fuel cut at 14.7 PSI. The Unlimited doesn't have fuel cut at that point (and I'm not sure when it does have fuel cut. It might not have that at all. Pettit would be the ones to ask on that part).

Just add a boost controller to go along with the ECU (or any ECU) and you'll be able to keep your boost at 12 PSI without any problems.

BTW, you can call Pettit. They are great guys and will answer your questions.

 

I have a Pettit Racing ECU with a unlimited chip in it and I'm running 14 psi for a while now, I spoke to Pettit and they said that with the unlimited chip you can run 14.7 as Mahjik said and there's no fuel cut but the stock injectors will not support anymore PSI so you will blow you motor up if you run more than that.

Get a boost controller and fasten the seat belt.

 

I still plan on calling pettit tomorrow, but my question isn't how much boost it can handle. I know that the stock injectors max at a little over 14. I will have a boost controller to hold my boost around 10 or 12 and then 14 when i wanna run real fast, but

Do i need to get a chip from pettit for my specific mods or car type(touring)?

 

no...the pettit unlimited chip basically has map points set up for the 14 psi or so...meaing the upper end of the map in the ecu are set for expected fuel requirements and timing for 14 psi. 12 psi is covered by the chip since its in a lower map area. Granted, you might be running 12 psi with different flow characteristics (intake, MP, catback, IC running 12 psi compared to just intake and exhaust running 12 psi, the first setup needing more fuel than the 2nd)....but with any chip set that you can't tune, it's not going to be perfect. What's your mods?

Tim

 

easy to answer. the guys at pettit. (kam mostly. ) Gets the stock computer.. Pulls The Eprom outta it.. reporgams it for 2 sets.. the unlimited, and the Normal one i think... the unlimited just throws more fuel into your mix because of mods / boost. the normal ECU isnt tweaked as much. ( map wise) and it throws just a little bit more fuel. and take out the Fuel Cut you get. thats all.. really simple.

btw anyone wanna buy a pettit Unlimited ECU .? 600 and its yours. + s/H its for a 93 RX7

 

my mods right now are dp, m2 med ic, cw airbox, exhaust.....of course i also have a fluidyne, pettit ast, profec b spec II, but those won't matter

the guy i'm buying it off of i believe has those mods plus greedy pulleys, pettit turbos, and maybe a midpipe. Pettit isn't open till tuesday so i gotta wait to call them to just clear up my questions