FAST sytem or DFI, anyone build motors and tune with these?
VIP Member
12-19-2007, 08:26 PM
#12
Registered
I have been using a Megasquirt system for the past two seasons. I had to do some modifications to run the low Z injecotors and found that timing chain and cam flex and MSD dist cause a wide varition in tach signal.. so a crank trigger fixed that problem. I was able to lean the motor down and best run so far netted me 4.1mph over my past best.
Megasquirt is not for the faint of heart, but you can buy them assembled and build a wiring harness to fit your needs.
This winter I hope to presurized the motor and see how the Megasquirt and I like it!!
Dick
Megasquirt is not for the faint of heart, but you can buy them assembled and build a wiring harness to fit your needs.
This winter I hope to presurized the motor and see how the Megasquirt and I like it!!
Dick
Did you build yours yourself? Did you use anything to coat the board afterwards to prevent corrosion? I'm considering using these on my engines too. I have Mefiburn now, but by the time I buy harnesses for the mefi stuff, I could have purchased 2 of the megasquirts! I think this is a better option over going carb.
Frank
12-20-2007, 06:04 AM
#13
Charter Member #601
Charter Member
Frank,
I did build it myself and ended up doing a lot of modifications. I used a peak and hold driver board to fire my injectors, works much better than the PWM. I can give you more info if you'd like! Send a pm or email.
I havent yet coated my board. I mounted (actually still laying in the gunnel).. It is finished and running so that may be a good winter project. Thinking of a second one to set up for NA after the Procharger, so I can run either NA or PSI..
Dick
I did build it myself and ended up doing a lot of modifications. I used a peak and hold driver board to fire my injectors, works much better than the PWM. I can give you more info if you'd like! Send a pm or email.
I havent yet coated my board. I mounted (actually still laying in the gunnel).. It is finished and running so that may be a good winter project. Thinking of a second one to set up for NA after the Procharger, so I can run either NA or PSI..
Dick
12-20-2007, 07:34 AM
#14
Racer
I built a 502 procharger 725hp engine using a fast(was fel-pro back then)back in 1998,the unit worked real well and was fairly easy to tune,I tuned and experimented on dyno then insalled in boat in closed loop,had another af meter in other exhaust.The tune up was fairly close except coming on plane(was lean) added fuel in those cells and was good to go.These systems are great for the person who enjoys tweaking,tuning and tinkering with there motor combo,you do need to spend some time on your tune up to get it perfect.Once i got mine tuned i removed wide band sensor and put it in open loop mode.That tune up is saved in lap top and can be down loaded into another ecm,thats wy engine builders build a combo(cid,cam,head etc)and keep that same combo so they don't have to spend a lot of time re-tuning new combo.The engine is still running no problems
MDG you are so right on the same combo and also there are things to get set before the programming even starts like the throttle pos sensor, the mininum air rate for the IAC to work properly, your base timing set to where it needs to be, the right thermostat to control the water temps because everything works off coolant tables. We program alot of Mefi ecu's and we can get them close but to do the job 100% I need to sit in the boat with a 02 sensor to dial it right in. So make sure all these things are right before tuning.
12-20-2007, 08:15 AM
#15
I had to do some modifications to run the low Z injecotors and found that timing chain and cam flex and MSD dist cause a wide varition in tach signal.. so a crank trigger fixed that problem. I was able to lean the motor down and best run so far netted me 4.1mph over my past best. Dick
You know, SEVEN years ago my engines were doing some really strange stuff like yours. So, I installed some crank triggers and told my engines to pretend that they're in a car and guess what?????......so far (for the last 7 years) my crank triggers have worked flawlessly! Figure that one out!, but...shhhhhh---don't tell anybody!
Glad you're getting it dialed in!
Last edited by KAAMA; 12-20-2007 at 08:21 AM.
12-20-2007, 08:29 AM
#16
We have been running a closed loop FAST system on a Supercooled, ProCharged 548 for 4 years and 400+ hours with absoloutely no problems.
Once your main parameters are set as Tyler stated then you can surely get it very close on the dyno.
Go take a few 10 minute data logs in closed loop in the boat while coming on plane, cruising, deccel, WOT, hard accel, etc and then go back to the comfort of your desktop and dial it in spot on to what you want.
Note: The above motor was just torn down for a refresh and the chambers and top of the pistons look like it was run about an hour rather than 400+ as do the cylinders. I attribute a lot of this to perfect A/F ratios achieved with the FAST EFI.
Dave
Once your main parameters are set as Tyler stated then you can surely get it very close on the dyno.
Go take a few 10 minute data logs in closed loop in the boat while coming on plane, cruising, deccel, WOT, hard accel, etc and then go back to the comfort of your desktop and dial it in spot on to what you want.
Note: The above motor was just torn down for a refresh and the chambers and top of the pistons look like it was run about an hour rather than 400+ as do the cylinders. I attribute a lot of this to perfect A/F ratios achieved with the FAST EFI.
Dave
Last edited by Nordicflame; 12-20-2007 at 08:33 AM.
12-20-2007, 09:36 AM
#17
Registered
Gold Member
Have twin engine twin turbo 30 Superboat. I bought two Electromotive EFI setups in 1993 and a laptop. Installed motors and EFI started tuning in 94. Came with parameters disc that was close. But tweaked it a little. Havent had any trouble in 13 years. Knock on wood. I got a little worried sitting in the cabin tuning motors flying down the river. So i could see the screen ajusting the fuel curves, timing, volumetric efficiency,air fuel ratios at different KPA vs RPMs.
12-20-2007, 01:44 PM
#18
Platinum Member
Platinum Member
Tyler,
Is it practical to dial in an EFI setup like FAST with no thermostat and a constant low water temps? Would you use a crank trigger inigition?
I am out of time this year, maybe the EFI project starts in the fall.
Sprague
Is it practical to dial in an EFI setup like FAST with no thermostat and a constant low water temps? Would you use a crank trigger inigition?
I am out of time this year, maybe the EFI project starts in the fall.
Sprague
12-20-2007, 11:47 PM
#20
Registered
I've never used the FAST but know a lot of guys that do and are happy with it. I use a MEFI for one reason, knock protection. No aftermarket ecm has a sophisticated knock protection like the MEFI. Since I am building engines for all types of people with all types of driving styles, trying to find all the hp that I can, and offering a warranty on all of them, I need all the protection that I can get. Now, they are not very user friendly, but they were never meant to be. Just like anything else, it's harder for a reason. There is just more to it, more tune-ability. I have the option to use any ecm that I want and I choose the MEFI. Good luck with whatever you choose, Eddie.
