That's thinking outside of the box! Cool idea. I think some of the guys running PSI's were doing something similar. If you plumbed that into your exhaust at the right spot you'd probably reduce reversion potential as well.

Rookie,
We are working on almost the exact same thing for these engines. Dustin Whipple is doing it as well on the engines going in his new OL. For example, you pulley the engine for 15 psi and only let it see 10 or so. What it does for the torque in the lower rpms is crazy. It also lets you make your target boost in any conditions. It is basically the same thing that Merc is doing with the 1075, 1200, 1300TT, etc. This is another reason that I would like to use the 555 since it has the ability and we all know it works well. As with yours, because it's controlled by the ecm, you can always let the engine see all of the boost that it is capable of making. The biggest benefits that I see are straightening out the distribution by speeding up the blower and increasing low and mid range torque by a considerate amount.
My biggest hurdle has been location for everything. I have an idea but it will require me to move a lot of my current stuff. I think it will be the best and most unobtrusive in the end, but it won't be quick or easy.
Haxor, thanks for the reply. I am trying to set up to run wet headers but there are a few hurdles to overcome. Not quite sure what to do yet.
Eddie

Sounds like you are on the right track and having some fun Eddie.

Dustin was in the loop back in 2009 / 2010 after we'd done this. A few of the Ford Powertrain engineers got a kick out of it too when they saw what we were up to.

Great to see you guys continuing the work and development in this area. It surely has huge potential, and its always fun playing with these type of solutions.

Back on topic:
Haxby, hit me up offline about the Holley set-up please. Email would be great.

Ya, fitting it all in and making it look nice will probably take a bit of doing. With the PSI's some guys are using this system to take some of the low speed boost and torque away to keep parts alive. I bet with the torque you'll be making with the quads it'll be nice to have the same ability. We've been doing the same thing with Prochargers but we don't have to bleed any off down low, just up top. It creates a boost curve similar to a turbo instead of the usual linear centrifugal boost map. The plumbing is much easier for us though as we can just vent off the pressure tube prior to the intake. It also allows multiple tune ups without changing pulleys so you can run anywhere from 89 octane to race gas by just flicking a switch. It seems like anything you can dream up can be accomplished with today's technology.

Done

Ain't that the truth Haxor. It makes our job that much better. Not to mention how much fun it is to play with cool chit.
Eddie

Eddie, Are you tuning the 555's yourself or are you locked out of them, Smitty

piston ding
 

sorry to bust in, but I have a strange issue with a pair of 502 mpi"s I'm overhauling and converting the valve train to hp 500 spec's via Bob Madara. the weird thing is the port engine has a small ding on the #4 piston from exhaust valve, then after disassembling the other engine I found the same exhaust valve dent on #4 piston. I don't know the complete history on these motors, but they are stock 502mpi's. Seems very stange to be only one piston and on same piston on each engine.

Dude- doesn't have a whole lot to do with HOLLEY EFI, start another thread!! Smitty

No, unfortunately I can't get in them yet. I'm working on it though. That is the one and only thing stopping me from using them on this 4.0L quad project. It will do everything that I want and need. I've considered flying out to Whipple with them and tuning them there, but that's a pain and I still can't do any fine tuning. I still have a little time before I need to make a decision so I am looking at all of the other boxes out there, including the Holley.
I'm hoping that the intake that I'm using will help a bunch with the low speed distribution issues and I won't need to rely on the individual injector trimming as much. However, if I do need it, the 555 has unlimited ability to trim individual injectors throughout the entire rpm range.
On top of that, it has electronic boost control.
Eddie