TRD/ Magnuson 4.0 Supercharger Tips, Tricks, and Mods

One of my plans if I go to Baja for an extended period of time is to carry a spare stock non-TRD ECU and if I get stuck without premium or run out of octane boost, remove the belt and plug in the stock ECU.

 

Not saying it won't work, but I am curious because you should technically have bigger injectors than the stock tune is accounting for. I wonder if just removing the belt would be enough instead of swapping ecus?

 

The secondary back up computer would have to have the injectors scaled to the size that his injectors are in order to work properly, same goes for the MAF if that is modified, coolant values if running a cooler t stay, etc etc.

There is no way he could plug in a stock PCM which is not modified for his setup, by pulling the belt or not.

By pulling the belt without swapping the current PCM, all of your modified values stay intact so nothing changes except the fact that you are not building boost anymore. All you would ever see if 0 in. hg. at wide open throttle.

 

I also wonder if it would be easier to make the bypass valve stay open all the time. I have never done it but I think I have read in the forum somewhere that you can zip tie it to stay open or am I thinking of something else maybe?

Would hate to see him swap his ecu and mess up his engine or something because it's not accounting for all his mods

 

Not that I'd really recommend this, but from the tuning perspective I think you could *in an emergency* run with the TRD S/C Tune and the belt removed. This assumes you're going to drive it civilly and not play around. The point would be to get the truck someplace where the belt or fuel situation could be remedied.

Looking at the two timing maps of a N/A truck and SC truck, the SC truck runs a bit more advance in the lower load areas to help idle/stalling and other things. Essentially to have the engine produce more torque to overcome the additional rotational mass of the rotor pack and associated pulleys. That can be a bit much for lower octane fuel to digest, but there's a pretty robust knock control system in place that would be able to combat that. However, I would not rely on this for any long term operation. Again, for emergency situations only.



The fueling is sufficient for N/A use or even low octane N/A use with the belt removed. So this is really a none issue. The plus here, is that your already calibrated for the injectors. Simply swapping in a N/A ECU would not be ideal as your injectors are calibrated for approximately 320cc/min flow versus the 455cc/min flow of the TRD injectors. This will have you pumping LOADS of additional fuel into the engine. I do not believe the Fuel trims would be able to compensate for this difference even under the best of conditions!

 

I would strongly encourage zip-tying the by-pass open if the belt was not removed.

 

See, this is why I put my ideas out there because y'all drop a bunch more knowledge onto me.
One of the reasons I haven't self-tuned yet because I haven't dedicated enough time to learn enough info to not destroy the engine.

 

I can say I for one respect that approach!

 

Ditto on this.
I feel like a newb and an idiot in most posts I make on this thread, but I'd rather be both of those than have a ruined engine!

 

Finally changed out my plugs after 65k miles on them. I was putting it off since I thought it hard to do with the supercharger. Love these forums for the help.

Truck ran and still pulled hard even with 3 bad plugs lol.

 

Yup. Anybody thinking they can drive as usual without a belt is mistaken. The truck is basically in limp mode.

 

Definitely not "as usual", but I'd like some extra protection if I'm stuck running too low of octane on a trip. More than just "just don't lay into it".

 

In cases like this, I'd keep a cheap laptop and your MPVI2 with you. A tune built specifically for a belt breakage or a "I can only get 87 at this pump" tune could be done and it would be as simple as loading the "contingency tune".

 

Me too.

 

There will not be any knock or pinging. It will be the complete opposite. The 455 injectors will flood the engine with fuel sans belt. This staying out of boost and it will drive fine is a false narrative. There is much more going on tuning wise than just that. The engine will bog down at times no matter how ginger you drive.

 

This sounds ideal for my situation... but I know nothing of creating the 87 tune in order to load it. I've spent a little time trying to learn about tuning but a lot of it is going over my head.

The emergency things are nice to know, but for daily operation for the foreseeable future "keep under 2500rpm" isn't going to work for me. Zip tie on the bypass might be alright for a bit.. although definitely not ideal either.

 

Oh you mean this tidy package that fits behind my rear seat? (Laptop, power supply, Tactrix, AND MPVI2)

 

Wouldn’t it just be better to buy some octane booster and just take it easy keeping it as is until you can get 91?

 

You're talking about running a N/A ECU on a S/C equipped engine correct?

 

Yes, but if you run out of all options and are stuck with 87. You never know, because Baja.