Hi again, In an earlier post I wrote how I swapped an '04 motor in my '97. She runs OK but very rich, I expected this as I'm running stock computer and MAF with 21 lb injectors as opposed to 19. I don't have any experience with the DIY tuners but pretty much know how the program works. My question is this: Should I get somnething like an SCT and guess the A/F ratio or would it be more worth my $500 for a dyno tune. I don't really care about wringing every ounce of power out of it, I'm just not sure how much flexibility you get with a handheld. I also plan on adding cams in the near future and maybe some other stuff, how many tunes can you get from a DIY? or is it unlimited? Thanks for the help,

Steve

 

From the what I can tell you put these 21(24?) lb injectors in without recalibrating the MAF. This is going to cause a problem. I think, and stress think, that a tuner can allow you to reprogram your MAF sensor. A good dyno tune would be your best bet. They can load the tunes onto an SCT chip and they can run a toggle for you and you will be set.

 

Brent at www.brenspeed.com will set up a custom tuner for you that will compensate for the extra fuel. Give him a call. All of the SCT's he sells come with 3 custom tunes for your mods and 3 octane ratings. Mark

 

I'll sell you my predator tuner, and you can use it!

 

usually when you go to a higher injector you need a maf that is calibrated to that size injector. You you can buy a maf calibrator or you can go to a tune shop and have them do it for about the same amount of money if not more.

 

From everything I read, The stock injectors that came with the '04 motor I put in are 21 lbs. (they are the pink/purple ones) I was figuring that with this setup, I could probably set a program to run it "lean" so it would actually be running closer to a stock A/F ratio. Or just find a stock 2004 MAF and cross my fingers. I woulld like to have the tuner as opposed to the chip so I can tweak it myself down the road. My plan for right now is probably to call someone that writes the tunes and tell them my whole setup to get a base tune, and I'll go from there if I need to. Thanks for the replies,

Steve

 

I tried a few things while waiting for a dyno tune and my bank account to calm down after the motor swap. It still runs rich but I've also discovered that after downshifting and then releasing the clutch the motor dies unless you tickle the throttle. I tried 2 known good IAC's with no joy, swapped in the 19# injectors, runs the same, sprayed EVERYWHERE for a vacuum leak, disconnected the speedo sensor (long story but ultimately waiting on the tune), and discovered a crack in the H-pipe about 3" long before the front O2 sensors. Will someone PLEASE tell me the new H-pipe and correcting the speedo will straighten her out a little! I just don't want to show up at the dyno on the big day and have to go home and fix something else. If I'm not mistaken, The input from the vehicle speed sensor has some effect on the ignition timing and/or injector duty right? I've known the guy that's gonna tune it for a long time and he's GOOD but I really don't want to waste his time troubleshooting. Thanks and if/when I get her all straightened out I'll be sure to post numbers.

Steve

BTW: Is $550 for an Xcal II and dyno tune a good deal?