I have a JRSC'd 1.6 that I want to dyno tune using megasquirt PnP. I have the rising rate fuel pressure regulator on the car now and wonder if its advisable to keep it on the car or to remove it. I wasn't sure if the RRFPR would **** up tuning or complicate things more. Also, I see alot of guys here using the LC-1, whats the merit of it and what does it do? Does it go well with megasquirt users? Do I need it in order to dyno tune? Right now, my car has the bipes acu and apex sfc that im gonna yank out when I do the install. I was gonna tune it at churches auto in socal since I heard they were basically the **** at what they do. But yeah sorry for being a megasquirt virgin, just wanted to ask experienced users so at the time of install i dont have to guess and test. Chime on INNN!!

 

If you remove it, you will need larger injectors. If you keep it in, the VE table will look a little different under boost, but it will work.

It's a wideband controller; we've used it with MegaSquirt in nearly all our own installs. The stock O2 sensor on this car can tell you if you're rich, lean, or at 14.7:1, but doesn't do a good job of telling you how much richer or leaner you are. You'll need a wideband to tune a boosted motor.

You'll need a wideband. It could be an LC-1 permanently installed on the car or one the shop puts in temporarily.

 

Moved the thread so it'll get some better exposure.

Matt speaks the truth. The "right" way to do this will be to remove your RRFPR and install a set of properly sized injectors. With an MP45, you're looking at maybe 160-170 HP tops, so 330cc injectors would suffice. I'd suggest going one step larger, however, in case you decide to upgrade. 440cc injectors are widely available new, or you can get a set of used red-tops from an '89-'91 non turbo RX-7 (460cc), have 'em cleaned by WitchHunter or Injector Rehab, and have enough fuel for well in excess of 200 WHP when the time comes.

Matt is correct in that the wideband is technically only needed during the dyno tuning phase, however I personally wouldn't own a forced-induction car with a standalone ECU without one. The stock narrowband sensor is useless when you're in boost as it can't tell the difference betwee, say, 13:1 and 10:1. It'll read 'em both simply as "rich". Get the LC1, along with a dash gauge (I love my XD-16, though the less expensive G series will also suffice.)

 

thanks, I forgot to say that i have a 255lph walbro too. So even with the high flow fuel pump, will I still need larger injectors. Can I get away with removing the RRFPR while keeping the walbro 255 and tuning with this for the extra fuel?

 

better off with larger(than stock) injectors anyway. I'd rather have injectors that aren't maxing out giving myself some headroom