First Post---1998 4700LPX and a couple questions

[Power Hungry]

Originally Posted by Jackpine

And, Bill - just to set Kevin's mind at ease, increasing the rev limit by his proposed 100 RPMs is safe, correct? I'm sure it is, or you would not have told him how to do it.

- Jack

Yes, 100 RPM on that engine won't hurt anything. It's basically a 7.3L like the Ford Power Stroke, and they run up to 3800 RPM. The Navistars are limited to 2700 RPM. Even bumping to 3000 (+300) RPM is perfectly fine.

Originally Posted by ybyrental

Thanks, guys. Just trying to keep it in a pretty safe mode.

I did have a boost gauge prior to the Orion, because we were curious if we were losing any power over time. When it has always been underpowered, it's easy to think that you are even losing more. From what little information I did gather, the general consensus was about 17psi under max load in stock configuration? I was getting around 16.5psi, so I figured that we were still getting full output.

Now---foolish me....I put a 20PSI boost gauge in the truck, not knowing that your reflash kit existed. Like I mentioned, I'm running at power level 4, and it obviously goes beyond the 20PSI max reading. If I was guessing, maybe it maxes around 22-23PSI at this level? A higher boost gauge is on its way. I also put in a pyrometer, and so far, my max temp on my heaviest pull has been around 1050 degrees.

I figure I'll stay at this power level until I'm confident my most heavy hauling doesn't send those temperatures much higher. But if you were to guess, how much higher EGTs could I expect going up one more power level? How much higher boost pressure?

With the moderate tuning, you should see 22-25 PSI. That's perfectly normal. Also, 1050 on the Pyro is great. Anything under 1150-1200 sustained under load is fine.

Hope this helps.

[ybyrental]

I appreciate it.

Once you get the taste of something, you always want a little more....

[Saratoga Express]

As far as turning the governed speed up, Bill has told me that some of the tractor pulling dudes are turning 4000+ rpms. But in the real world, even Ford had the 7.3 governed at 3200 rpms and you never hear of them destroying themselves. A couple hundred won't hurt it. But it might void your warranty with Navistar!

[Power Hungry]

We regularly like to set the Rev Limit to 3200 RPM on the T444e and 3000 on the DT466/DT530. The 7.3L in the Ford is 3600 RPM from the factory and we've pushed it to 4000 RPM (or even higher) for performance applications. The 444/7.3L is a solid, proven engine as evidenced by the fact that they haven't been produced in 20 years and are still banging away out on the road.

I hope this is helpful.

[ybyrental]

This little guy has been dynamite for us. I won't speak about the legalities of our hauling(may be a little overloaded ), but we are constantly hauling 20-30k with this guy. That's why I was hoping for a little more uumph than stock, but not putting reliability out the window. I'm running on the 230hp level, and it's been great. Very, very happy with the Orion system.