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ISX

How to Make the Perfect 12V

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ISX

Figured I would give everyone a guide for a 12V that is perfectly powered and efficient and reliable. I am thinking this will get you to around 350-400HP with controllable EGT's. This will give you a truck that doesn't smoke a ton and is very efficient.

The catch is that I am not sure if this will work for everyone. My truck has the stock lift pump and I am not sure it is flowing like it used to, though I got a new overflow and it holds at the right pressure so I am thinking it is fine, but it doesn't smoke like it used to. This guide is for someone to try it and see if it actually clears up the smoke, drops the EGT's, and has efficient power, as mine improved little by little as I did each mod. I just want to be sure I'm not delusional :lol:

Step 1: Get a BHAF. This will improve flow and make the filter media last longer since there is more surface area to get dirty.

Step 2: Get a 4" or bigger exhaust either straight piped or with a see-through muffler. Again, this improves flow.

Step 3: Get a pyrometer and boost gauge if you haven't already, otherwise you are asking for trouble.

Step 4: Set your valves at 0.008" intake and 0.015" exhaust. Only do this if you know exactly how to do it, as this is a tight tolerance and is the minimum setting on exhaust so if you screw it up a lot, you might end up having a valve open the whole time. Typically valves loosen, so if you get it set perfect, you shouldn't ever have a problem. The minimum settings are what they are because valves expand as they heat up so this accounts for expansion. This should make the HX35 spool up better than an HY (after we do AFC mods).

Step 5: Get a boost elbow and set it to max out at 35psi (though you will probably max out there with the wastegate stock). This might be a problem as I use something that keeps the wastegate completely shut until 35psi, so I get to 35psi much earlier, but try the elbow anyways as it might work just as well.

Step 6: Get a 400HP clutch (or better). If you don't, you might as well stop here. If you have an automatic, get it built up or something (I don't know anything about the auto's but I know the stock one's don't hold up).

Step 7: Take the AFC arm out of the AFC housing, taking the AFC out of the picture (since the arm is out of the picture). This will leave the fueling up to your foot, which is nice.

Step 8: Take the fuel plate out. Again this leaves fueling up to your foot but also provides max fueling.

I would like to have someone with a 215HP 12V do this setup and see what happens. They should have only a haze or slight amount of smoke (after the turbo lights) and the EGT's should be much harder to get over 1200F. The turbo should light extremely quick as well.

There are some other things I did that might have made a difference as well but I don't know if anyone would go that far:

[*]Remove the Fan

[*]Remove the Fan Shroud (this means doing something with the overflow and wiper fluid)

I think taking the shroud off allowed the air to free flow through the intercooler more since it isn't running into the shroud on the sides, giving lower IAT temps under high boost conditions (when your getting near 1200F).

Here is the part you must know and is key to success. With no AFC and no fuel plate, flooring it means max fuel at any point in time with or without turbo boost. This means you can get a ton of smoke down low before boost is built if you happen to step on it. You must get a feel for the pedal. The rack inside the pump only moves a fraction of what the pedal does. If you get in the truck, turn the key on, bump the starter (don't start it, bumping it engages the shutoff solenoid), and push down on the pedal easily until it gets hard to push (should only go down an inch, maybe less), that is actually full rack travel because the governor flyweights are not fighting you since they are not spinning. You can feel that in the pedal when you step on it, if you can just ride slightly behind that hard spot, it will move dynamically with engine RPM until it is to the floor (3000 RPM). The 215HP pump retards timing (none of the other pumps do) when the rack is all the way in because it has to jam more fuel in to get the higher HP rating. It is 4* retarded IIRC. To keep the engine efficient, you don't want it to be retarded, you want to keep the rack slightly behind that full rack spot so that it isn't retarding timing. If you put it to the floor and then do this method, you will see that the truck is faster when you ride slightly behind the rack.

Fuel plates do this for you to an extent but not nearly as good as your foot is capable of doing. There is a reason 24V guys have many different levels. You can adjust your plate constantly, or you can take it out and adjust your foot constantly. After a few weeks (give or take), you will be a pro at it and be able to dynamically control fueling better than any chip can even dream of doing. It will become 2nd nature. You will know when it is going to smoke, when the turbo is going to light, everything and have 100% control over it, not riding some AFC or fuel plate that might not be the power you were wanting for that particular instant.

This takes some tedious footwork but is really not that hard. I had one of the two springs fall off the throttle and I can press the pedal to the floor with my pinky. I had to readjust my footwork but after 2 days it was back to being 2nd nature and it's kinda nice not having to press hardly at all.

If anyone wants to try this, do everything I said (cept the optional stuff) as they all add up to success, then let me know your results.

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