My setup is a freshly installed Procharger (9psi) w/3 core intercooler on a '97 LD F-250 4x4 5.4 litre, auto w/3.73 gears. No other mods except for a flowmaster exhaust system. Stock programmed ECU.
My problem is that I appear to be running too lean. I have the booster fuel pump with the FMU maxed out. On the dyno, air/fuel ratio is in the 13.5:1-12.5:1 range (and hp & torque #s are low). I'm supposed to be targeting 11.5:1. Is it possible to get me there through the use of a chip or programmer? I'm trying to avoid replacing the injectors, MAF, and still having to get a chip made.
I just made an appointment to get back on to the dyno tomorrow. I've made some minor changes, and will be recording data from the trucks ECU. I'm trying to see if the injectors and MAF are maxed out or not.
Any suggestions are welcome. Thanks. Dave C.

 

You are taking dangerous shortcuts - we will NOT tune ANY vehicle with an FMU on it, nor does an FMU have any place on any forced induction application - that is strictly a cost-cutting and dangerous shortcut that we will have no part of, we stopped doing tunes for FMU-equipped vehicles years ago. You have to do stupid things like command a 17:1 A/F just to get a 12:1 - bad idea.

You need enough fuel pump and injector capacity to allow the fuel pressure to run at STOCK levels on those return systems, as that is the ONLY way that the PCM can be properly put in control. And yes, you will generally have to increase e the MAF capacity as well.

We criticize supercharger manufacturers all the time for taking these damned shortcuts, and they do it because it allows them to sell their kits much cheaper, and then it's your problem when it blows up.

Every supercharger kit for any return-type fuel system vehicle requires a MAF meter upgrade (or MAF extender, very cheap & works fine), the CORRECT size fuel injectors and fuel pump that allow the fuel pressure to be run at STOCK levels in return systems, AND proper custom tuning to make it all work correctly - anything less is not acceptable, and will lead to problems sooner or later - in your case, obviously sooner.

Bottom line - you are taking dangerous shortcuts (you probably didn't know that until you read this post, but that's the reality of your situation), and are on your way to a potentially blown engine if this is kept up - we will not touch it's tuning in that configuration.

If you want to call us to go over this properly to find out what it will cost you to have us set this up RIGHT, so that it is actually SAFE, our number is listed just below & we'll be happy to go over this with you.

PS - this is a very simple matter of what is *required*, OK? I'm really not trying to play "salesman" with you about this, unfortunately you just happen to have a dangerous configuration that must be corrected.

 

Thanks Mike. I will be calling you sometime next week. Dave C.

 

Hi David,

You're more than welcome, of course!

And pardon me if my last post seemed a bit heated, it's just that every time I see a supercharger manufacturer send a Kit out like that, it makes my blood boil for the unsuspecting vehicle owner, it's just not doing you right, you know? It's like each vehicle owner ends up having to be darn near a supercharging expert on his vehicle to even be able to know if what they got is safe or not, or is even appropriate, etc.

For years & years, the "standard" (unfortunately) of the supercharger industry was to send out those darned FMU's so that they could get away with telling the vehicle owner that they did not need fuel injector or a MAF meter or any custom tuning - in other words, a "bolt-on" kit to run on your stock factory tuning - very bad idea. They did that simply because it reduced he cost of the kit by roughly about $1000, and that makes all the difference in the world in how much blower kits they could pump out the door. Absolutely irresponsible IMHO - now over the years, a few of them have started doing things like including fuel pumps, injectors, tuning - but still nobody does MAF's, and it's very few that even look at any of the other absolutely necessary upgrades.

So when I see someone that gets a kit sen t to them like that, it just makes me angry *for* them, you know?

Some of them, like Powerdyne for example, doesn't even bother to upgrade the fuel pump in their kits for the 1997-2003 F-150's - no excuse for that kind of cost-cutting.

At any rate, I just wanted to explain a little bit better - thanks for your post & we look forward to speaking with you at some point!

Good luck,

 

Mike, I tried to call you today. You're a busy man! I've got a chance to buy a set of 42lb injectors and a 90mm (lightning) MAF. It's all brand new parts and a great price on the package. Would this be a good choice for my set-up? Would you be able to set me up with a good tune, or is it going to take a few times to get it dialed in? I left you my work #. I hope to talk to you today. I need to get this corrected. I have a lot of towing to do over the next month. Thanks. Dave C.

 

Hi David,

Yes, I know you called, I was on another line at the time and I had one of our staff try to reach you a number of times at your work number - and I called it myself as well - but none of us ever got any answer, the phone just rang & rang, and no voice mail, either.

We also left a message on your home phone as well.

I suggest just giving us another call so we can hook up & go over everything.