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Thanks for asking. I live in upstate SC and travel into the mountains of NC fairly often, so I'm just looking to be able to maintain at least the minimum legal speed of 45MPH up some of the steeper main highways. Right now I can manage about 39MPH in 4th gear (it's a 5 speed tranny). Of course on the flat and up "normal" highway hills it can maintain 55-60MPH with no problem. The steeper sections I am referring to are ones where 90% of the fully loaded semis are able to do better than 45MPH, so I'm hoping to find a way that I can too.

The 4BT in my full-size Bronco is a 105hp model with VE pump, and was stock until last week when I had my mechanic install DDP Stage 1 injectors, which definitely made an improvement, but not enough. And I noticed the improved injectors made no difference to peak boost on the H1C.

The boost ramp-up on the H1C is very linear with RPM, which I spose is to be expected when there is no wastegate? My failed attempt to switch out the H1C for the HX30W this week held the hope that the improved turbo design of the HX30W together with the wastegate would lead to higher boost in the 2000-2500RPM range, and would continue to increase boost up to my self-imposed max of 3000RPM. But as I mentioned in my prior post, the HX30W couldn't be made to fit in the engine bay.

Other things that might be of interest:
  • Several months ago I installed a fuel pressure gauge and it always shows a steady 6lbs at all RPM and all throttle settings until/unless I go above 3000RPMs, which I did once to 3200RPM just to see what would happen. On that occasion, the fuel pressure dropped below 6 but I dunno how far below (I had it set to alarm below 6, and it did, but I was watching the tach, not the pressure gauge).
  • There is no smoke unless it sits without being run for a couple days. In that case it blows some white smoke for about 30 seconds or so after it starts. The longer it sits, the greater the volume of smoke it blows when started. Let it sit 2 weeks and it looks like a white fogger for the first 20 seconds after it starts. But no smoke at all if it's driven every day.
  • I've never messed with the smoke screw nor idle screw and can't say I understand those anyway. I have read that DDP's modified fuel pin may give me the slight power increase I'm looking for, so I'm thinking I may try that.
  • There is an hour meter on the motor. Dunno if it's accurate, but it reads about 1100 hours. Just grasping at straws thinking that might be about the life of an H1C. That, and reading so many other posts that speak of getting >10lbs boost.

Many thanks for any advice!
 

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This is hijacking the OP's post, start your own thread and we can continue to help out.
Cheers Steve
 
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