FordNut
30-06-2004, 03:55 AM
Background: I currently have a 2003 Mercury Marauder, which has the same engine as the '03-'04 Mach1 (basically the same as the'01 Cobra). It is a 4.6L dohc 32 valve V8 with 10:1 CR. Currently I have virtually all mods possible on a NA car except a bigger MAF sensor, which is soon to be installed. It is currently putting out 297hp to the rear wheels. I plan to supercharge next year with a ProCharger D1SC and air-air intercooler. Most people using blowers on the Marauder are running 8-10 psi boost with a air-water intercooler and making about 450 RWHP. I've seen some of the Mustang guys are experimenting with WI these days so I know it can be done on these engines. Everybody on the Marauder forums poo-poos the notion of water injection but I'm not afraid to explore new ideas. So here is what I understand so far about WI, along with some ideas I have for implementation and some questions.
If possible I would like to get a system that is adequate for the SC application and install it while my car is still NA. I believe the only additional parts I would need are a vacuum switch and nozzles?
Safety interlocks should cut timing and boost if there is no water flowing and should prevent the pump from running if the tank is empty. I have seen a diagram of a pressure relief system posted in these forums which is for a turbo, would something like that work on a blown application? How would it be plumbed? The timing change could be handled by switching to a different program on my chip. I have a flip-chip which currently has two programs (a 93 and a 91 octane file) but it could be reflashed so that one program has timing for WI and the other without. Is there a signal available from the Aquamist controller to handle this switching?
Is the Aquamist pump compatible with all 3 commonly used alcohols (isopropyl, ethyl, methyl)? If not, what pump would be recommended that is compatible? And would it work with the Aquamist controller? Does it have adequate capacity for approximately 500 RWHP (~600 FWHP), or would dual pumps be required? Are accumulators commonly needed or do the pumps just run deadheaded?
It seems like the more accurate control method is to use the fuel injector duty cycle to control the water injection rather than just sizing the nozzle for max demand. What are the negative aspects of this method, if any?
Location of the injector(s) should be between the intercooler and the throttle body, but does it make any difference whether it is close to the throttle body or far away from it?
Would this application warrant multiple water injector nozzles? If so, how should they be controlled and where should they be located?
Does anybody have stainless steel nozzles?
My new MAF sensor has a separate IAT sensor (the OEM one has both sensors incorporated into the MAF itself) so I could locate the IAT sensor upstream, downstream, outside, or basically anywhere. Would it make sense to have it downstream from the nozzle(s) or does it matter? Surely it should be after the intercooler, shouldn't it?
Tuning is a big question mark. My tuner has never worked with WI. From what I understand, the process should be to tune the AFR for about 12.5:1 (that is what we have been setting the Marauders to anyway) without WI, then just leave it alone. The timing will be adjusted differently based on whether WI is on or off. So my programmer would tune for optimum performance at reduced boost (maybe 8-10 psi), without WI and then tune again for optimum performance with high boost (maybe 12-15 psi) with WI. This portion of the tuning should only modify the timing and not change the fuel tables? Burn those two programs into my chip and setup the WI controller to switch between the two programs. Does this make sense or am I way off in left field? And what kind of special tuning can be done to pick up a few extra ponies with the WI while I am still NA?
The Aquamist system is the only one I have seen that has the level of controls to make this happen. Any suggestions on what model and additional parts I should get?
Thanks for any help or advice for this WI newbie!
If possible I would like to get a system that is adequate for the SC application and install it while my car is still NA. I believe the only additional parts I would need are a vacuum switch and nozzles?
Safety interlocks should cut timing and boost if there is no water flowing and should prevent the pump from running if the tank is empty. I have seen a diagram of a pressure relief system posted in these forums which is for a turbo, would something like that work on a blown application? How would it be plumbed? The timing change could be handled by switching to a different program on my chip. I have a flip-chip which currently has two programs (a 93 and a 91 octane file) but it could be reflashed so that one program has timing for WI and the other without. Is there a signal available from the Aquamist controller to handle this switching?
Is the Aquamist pump compatible with all 3 commonly used alcohols (isopropyl, ethyl, methyl)? If not, what pump would be recommended that is compatible? And would it work with the Aquamist controller? Does it have adequate capacity for approximately 500 RWHP (~600 FWHP), or would dual pumps be required? Are accumulators commonly needed or do the pumps just run deadheaded?
It seems like the more accurate control method is to use the fuel injector duty cycle to control the water injection rather than just sizing the nozzle for max demand. What are the negative aspects of this method, if any?
Location of the injector(s) should be between the intercooler and the throttle body, but does it make any difference whether it is close to the throttle body or far away from it?
Would this application warrant multiple water injector nozzles? If so, how should they be controlled and where should they be located?
Does anybody have stainless steel nozzles?
My new MAF sensor has a separate IAT sensor (the OEM one has both sensors incorporated into the MAF itself) so I could locate the IAT sensor upstream, downstream, outside, or basically anywhere. Would it make sense to have it downstream from the nozzle(s) or does it matter? Surely it should be after the intercooler, shouldn't it?
Tuning is a big question mark. My tuner has never worked with WI. From what I understand, the process should be to tune the AFR for about 12.5:1 (that is what we have been setting the Marauders to anyway) without WI, then just leave it alone. The timing will be adjusted differently based on whether WI is on or off. So my programmer would tune for optimum performance at reduced boost (maybe 8-10 psi), without WI and then tune again for optimum performance with high boost (maybe 12-15 psi) with WI. This portion of the tuning should only modify the timing and not change the fuel tables? Burn those two programs into my chip and setup the WI controller to switch between the two programs. Does this make sense or am I way off in left field? And what kind of special tuning can be done to pick up a few extra ponies with the WI while I am still NA?
The Aquamist system is the only one I have seen that has the level of controls to make this happen. Any suggestions on what model and additional parts I should get?
Thanks for any help or advice for this WI newbie!