Anyone ever do a ram air intake on our trucks? Bhaf seemed to be a good help and a good friend swore by the ram air intake on his VMAX bike. I feel like it would help in our application (diesel no real air fuel ratio no throttle blade) but I know it's mostly a looks thing on regular gas cars. Just curious if anyone has ever messed with it.

Food for thought. When tuning for efficiency like myself less boost is better. More boost pressure more you are unlocking fuel to flow. This will in turn create lower EGTs and cooler running engine. Even with Beast at 500 HP it cruise at 82 MPH in 5th gear at mere 2,500 RPMs but keep boost below 10 PSI and EGTs at 700°F. At slower 65 MPH I'm right at 2,000 RPM but EGTs drop to 550°F and boost of barely 1 to 2 PSI.

Absolutely! The thought isn't to make more boost rather to "force feed" the turbo a bit and make it work a bit easier hopefully increasing flow. If I can feed it .5 psi more at the inlet and drive pressureand everything else stays the same i should see more at the outlet for "free" I'm not shure if it will help when it's cold outside these diesel seem to like their inlet air pretty warm. I'd like to make a intercooler bypass for that reason but that's a lot more fab then I have time for right now.

If you wanna increase flow of air all you need to do is retard timing and air flow is increased.

Up here cold air is deadly and kills the MPG. Forcing more cold air would require lot more advancement as well.

One of the reasons I love BHAF with the 2nd Gens

I'm guessing by retarding timing your wanting to spool the turbo more? At highway speeds my turbo really isn't pushing anything I float between 1 and 2 psi at 65mph. When I drop out of cruise timing I don't see any change in boost until I get onto it. 30+% engine load. Im hoping to be more efficient not necessary get more power. Wouldn't retarding the timing cost me cylinder pressure/energy for the ignition event?

Yes your correct. More you advance less air needs to be forced into the cylinder also fuel is cut and locked out at lower boost.

Currently my best is +30 MPG across state of Washington from Seattle WA to the Idaho border at 300 miles and barely used a 1/4 tank of fuel. Beast is capable of 500 HP.

Another tip swap to 200°F thermostat from a 6.7L. More heat, less advancement, better thermal dynamics.

I've been meaning to swap thermostats to a 200 degree but how do you keep the quad reading temp? Anything over 200 and mine gets funny. Gage cluster still works but all my alarms are based on the quad readings. I have probably read every post you and me78569 have written what yall have gotten these old trucks to do is nothing short of crazy.

Quadzilla above 204℉ will revert to -40℉. I have installed the transmission temperature sensor in the oil pressure test port. This allows me to adjust timing based on oil temperature. As you find out you can cut up to about 35℉ off the oil temperature vs coolant. I can run as high as 220℉ in coolant but float right around 170-178℉ in oil temperature.

Timing can make or break net temperature system-wide. Now that I've retuned around the average 210℉ coolant temperatures you don't need as much timing advancement.

Even the picture below I can do this for less than 5 PSI of boost normally.

Edited March 21Mar 21 by Mopar1973Man

Interesting

New thermostat is in the truck! Well sitting in the bag in the passenger seat. Was going to install that and try and simulate a hood scoop with a leaf blower to see the effect on egts and see if this is even feasible before I go cutting and welding. I figure i could run a high idle program on the quad and compare reading with ambient air and then blow a leaf blower at the turbo inlet and see if it makes any significant changes. I don't expect any changes in pressure to the inlet but maybe air velocity will have its own benefits. More to follow this weekend!

Not going to make any gains...

Timing is the ultimate EGT control once you understand how timing works. BHAF with 110℉ summer temperatures and still hold 700℉ EGT's at 82 MPH twisting 2,500 RPM in 5th gear.

I might disagree with you on that. Your absolutely correct tuning will have the biggest effect on efficiency power egts ect. But i think anything i can do to help that turbo work less shurely can't hurt. I guess we will know after some testing

That's where things change when your capable of running highway speed unspooled. This way you keep fuel availability locked down too if done correctly. Like my current tune i don't even use the canbus 60 HP. Im just running on injectors and timing. My CANBus is is limited to 80% to 90% for most driving. No spool.

Edited March 25Mar 25 by Mopar1973Man

Absolutely. And thats pretty much where I'm at. I know my tune is not as good as yours and i know me being an automatic is not helpful (my in park idle engine load is higher then your steady state highway engine load) My commute to work is only about 20 min thats just enough to show the oil/coolant difference on the drive in. I know it's probably a little one the retarded side for the in town driving. And like you suggested my fuel table is well under stock levels until I get deeper in the boost table. Egts are well under control for towing and what not (turbo is probably a little one the big side to tow perfectly) but I just want more out of it. The science of it all amazes me and I have a laundry list of things to try water methanol the ram air a intercooler bypass propane injection ect. I currently run a consistent 21 mpg per tank (hand calc ) on the drive to and from work. If I run to Dallas or Austin I generally get closer to 24. Towing 75hp skid steer on a trailer from Austin I got 14.

How about tire size and axle gear ratio?

I dropped from 265 down to 245 75 r 16s highway tires. glad I followed your frecommendations on that as well picked up a mpg and truck feels alot better off the line. Rear diff is 3.55 i believe. I forget the final drive number for the 47 re but I did target the range you specified in one of your discussions

You are 3.69:1 final ratio. Just you are tall on the 4th gear aitomatic 0.68 ratio vs 5 speed at 0.75 ratio.

Make sure on flat ground you can hold cruise timing but keeping boost below 5 PSI preferred.

Hmm so is boost more the limit then load for cruise timing? I've been pretty scared to go past 30% load with cruise timing. But my running load is much more then yours. I typically don't see 5 psi until closer to 35- 40%

I'm set for only 25% cruise engine load for cruise timing. Stock HX35W turbo so I'm a bit spooled at even 65 MPH. Crazy part i can use the full 8° of cruise timing but optimal i find my place based on engine oil temperature. Always watch temperature more it will give clues what works best. LOWER Temperature is better, less energy wasted in creating heat, more work produced.

Got a good chance to verify timing this is after an hour at 70-75mph. Unfortunately I think yall were 100% right on the the effect ram air would have. Filter off on high idle right on 300 degrees EGT leaf blower feeding it i saw some dips down to 298 but pretty steady 300 still. Out of curiosity I took my hand over the intake till I saw a change about 2/3 covering egt started to rise till about 305. Morale of the story how easy the turbo breaths makes a slight difference. But it really don't make much difference. Not worth cutting the hood up.

I can tell you an old member @isx did the math on cold air and hot air and there was a very very small change of amount of moles or molecules of air was in the air system even at boost.

So the best is to control you turbo and airflow by timing. Always remember lower the boost better the efficiency.

Edited 13 minutes ago13 min by Mopar1973Man