Lessons Learned

[steve05ram360]

Sharing some lessons learned, I'd expect you guys already know this.

Truck:
2002 Dodge Dakota 4.7 with 45RFE Trans 3.55 gears with 265/75/16 tires (worst case scenario, stock tires are a bit shorter and a good bit lighter as the tires on there are E rated tires, heavy)

Mods @ start of these lessons learned:
70mm Throttle Body
Air Aid intake tube between stock air box & TB
Fuel rail wrapped


Inspired by lessons learned on the Ram relating to the intake tube I set out to add a turning vane at the elbow on the intake tube. The change in performance was very noticeable and immediate. Power was up everywhere I used it. Fuel trims were up into the +7~9 range and if I'm not mistaken that is dumping fuel to compensate for a lean condition. Used simple 5" garden edging for the parts.

Pics...










Motivated by the performance bump I decided to play with expanding the manifold capacity by adding what I call a potato launcher tube off the brake vacuum hose. The original idea was to smooth out the vacuum variations in the intake manifold. The benefit was again immediate and to my surprise, bottom end torque jumped quite a bit. Further experimentation with the trucks setup taught me that I could shift the torque peak up & down the rpm range. Was pretty shocked by that.

Again leveraging lessons learned on the Ram I pulled the air box snorkel with the expectation that the upper rpm range for where I use it would get a bump in performance and sure enough it did. Below is a pic of how it was just prior to me wrapping the 2 1.5" tubes added. I used exhaust wrap for everything under there including the fuel lines.




So what did all this get me in the end...

mpg pre-mods were in the 15-17.0 mpg range. I'd really have to baby it to get 17 and even that was a stretch. Mpg's tracked over a 3 day commute period of 210~215 miles for all of the testing. When I enjoyed a DGAS tank mpg's would be in the 13~14 mpg range.

mpg post-mods are now in the 18-20 mpg range over the same 3 day commute test window. DGAS tanks are getting me 15-17 mpg now.

Now the downside... I do have a CE code for a large evap leak which was not there before. At some point I will be attempting to defeat the system on startup in an effort to prevent the code. No idea when it is testing for the leak, the only thing I can think of is at startup it is measuring the rise rate of the vacuum signal.

There has been no ABA testing, I dont have time for it so if someone here is motivated to do it feel free.

Anyways... lessons learned and lessons shared...

Forgot to add... I pulled the airbox snorkel and power shifted up the rpm range. That has motivated me to duplicate a Ram mod I did and put a vacuum controlled exhaust cutout onto the air box. there is room on the firewall side of the box. Here is the Rams setup.

[freebeard]

The turning vane seems pretty smart. They put those in wind tunnels.

Is that [quite proprer] bellmouth a secondary?

[steve05ram360]

Yes that is a velocity stack on the boost controlled valve. There is no room for that on the dakota but the valve will fit. I bought one off amazon but the actuator does not work (doa) so have to swap it for another.

[freebeard]

proprer? ghe? I miss the days when Ecomodder had a fuyncional spell checker.

[kach22i]

Originally Posted by steve05ram360

Sharing some lessons learned, I'd expect you guys already know this......................

Inspired by lessons learned on the Ram relating to the intake tube I set out to add a turning vane at the elbow on the intake tube...............

Motivated by the performance bump I decided to play with expanding the manifold capacity by adding what I call a potato launcher tube off the brake vacuum hose. The original idea was to smooth out the vacuum variations in the intake manifold. The benefit was again immediate and to my surprise, bottom end torque jumped quite a bit. Further experimentation with the trucks setup taught me that I could shift the torque peak up & down the rpm range. Was pretty shocked by that........................

Anyways... lessons learned and lessons shared...

Forgot to add... I pulled the airbox snorkel and power shifted up the rpm range.

I met an engine intake specialist from S. Korea about 15 years ago he was a guest/coworker of someone at a family Thanksgiving gathering. In short with many false generalizations and exceptions to the rule he said; the longer the intake tube the better the low end torque at expense of the high rpm power and vice versa the shorter the intake tube the worse the low end torque is but the power band moves upward to the higher RPM's.

Porsche addressed this with their VarioRam induction system, a system that kind of varies the length of the manifold air intake.

I could not find a good animation that explains the opening of the various intake chambers, but I think of it like a winded musical instrument, perhaps a trumpet with three valves that in effect shorten or lengthen the intake length.

https://talkingtrumpet.wordpress.com...-animated-gif/

[Ecky]

Originally Posted by kach22i

I met an engine intake specialist from S. Korea about 15 years ago he was a guest/coworker of someone at a family Thanksgiving gathering. In short with many false generalizations and exceptions to the rule he said; the longer the intake tube the better the low end torque at expense of the high rpm power and vice versa the shorter the intake tube the worse the low end torque is but the power band moves upward to the higher RPM's.

Porsche addressed this with their VarioRam induction system, a system that kind of varies the length of the manifold air intake.

I could not find a good animation that explains the opening of the various intake chambers, but I think of it like a winded musical instrument, perhaps a trumpet with three valves that in effect shorten or lengthen the intake length.

https://talkingtrumpet.wordpress.com...-animated-gif/

Quite a few manufacturers have used this over the years. Honda and Toyota have had versions on the Civic and Corolla, respectively, at different periods.

[steve05ram360]

Yeah its all been done years back, I am aware of the variable runner length designs and also the air box vent. I might have mentioned that Mini did it on the JCW kit on the cooper back in 2003-2006.

The bottom line is that on obd1 cars you could probably get away with the added vacuum chamber to the intake manifold and not get a CE light. You could put the torque right where you want it for the best mpg's.

I insulated the 2 tubes in an effort to see if the intake temps are better controlled and it looks like that might have helped. Temps are pretty decent for good mpg's but they spike too high when the truck is in slow traffic or city stop & go.

I can keep this thread posted if there is interest. I am restoring this truck currently and am working on the front & rear suspension so nothing to add for mpg's from it. I am running another 3 work trip tank to see if there is any change from the last tank.

[ttrainxl]

Originally Posted by steve05ram360

Sharing some lessons learned, I'd expect you guys already know this.

Truck:
2002 Dodge Dakota 4.7 with 45RFE Trans 3.55 gears with 265/75/16 tires (worst case scenario, stock tires are a bit shorter and a good bit lighter as the tires on there are E rated tires, heavy)

Mods @ start of these lessons learned:
70mm Throttle Body
Air Aid intake tube between stock air box & TB
Fuel rail wrapped


Inspired by lessons learned on the Ram relating to the intake tube I set out to add a turning vane at the elbow on the intake tube. The change in performance was very noticeable and immediate. Power was up everywhere I used it. Fuel trims were up into the +7~9 range and if I'm not mistaken that is dumping fuel to compensate for a lean condition. Used simple 5" garden edging for the parts.

Pics...










Motivated by the performance bump I decided to play with expanding the manifold capacity by adding what I call a potato launcher tube off the brake vacuum hose. The original idea was to smooth out the vacuum variations in the intake manifold. The benefit was again immediate and to my surprise, bottom end torque jumped quite a bit. Further experimentation with the trucks setup taught me that I could shift the torque peak up & down the rpm range. Was pretty shocked by that.

Again leveraging lessons learned on the Ram I pulled the air box snorkel with the expectation that the upper rpm range for where I use it would get a bump in performance and sure enough it did. Below is a pic of how it was just prior to me wrapping the 2 1.5" tubes added. I used exhaust wrap for everything under there including the fuel lines.




So what did all this get me in the end...

mpg pre-mods were in the 15-17.0 mpg range. I'd really have to baby it to get 17 and even that was a stretch. Mpg's tracked over a 3 day commute period of 210~215 miles for all of the testing. When I enjoyed a DGAS tank mpg's would be in the 13~14 mpg range.

mpg post-mods are now in the 18-20 mpg range over the same 3 day commute test window. DGAS tanks are getting me 15-17 mpg now.

Now the downside... I do have a CE code for a large evap leak which was not there before. At some point I will be attempting to defeat the system on startup in an effort to prevent the code. No idea when it is testing for the leak, the only thing I can think of is at startup it is measuring the rise rate of the vacuum signal.

There has been no ABA testing, I dont have time for it so if someone here is motivated to do it feel free.

Anyways... lessons learned and lessons shared...

Forgot to add... I pulled the airbox snorkel and power shifted up the rpm range. That has motivated me to duplicate a Ram mod I did and put a vacuum controlled exhaust cutout onto the air box. there is room on the firewall side of the box. Here is the Rams setup.

This has peaked my interest quite a bit. I can’t tell from the pics, but in your “potato launcher” tube, do you just have one nipple connecting the brake vacuum hose, or is there an inlet and outlet? I’m trying to think about how to adapt this to my Honda Civic. And being that you have two 1.5” pipes that appear to be around 18-24” long, maybe for my 1.6L Honda, I might want one small tube. I already have 2” black ABS pipe, so maybe a 2” id tube about 8-10” long might be adequate for my application. Might as well buy a handful of end caps and try a couple different sizes.

[steve05ram360]

Originally Posted by ttrainxl

This has peaked my interest quite a bit. I can’t tell from the pics, but in your “potato launcher” tube, do you just have one nipple connecting the brake vacuum hose, or is there an inlet and outlet? I’m trying to think about how to adapt this to my Honda Civic. And being that you have two 1.5” pipes that appear to be around 18-24” long, maybe for my 1.6L Honda, I might want one small tube. I already have 2” black ABS pipe, so maybe a 2” id tube about 8-10” long might be adequate for my application. Might as well buy a handful of end caps and try a couple different sizes.

Yes on the tube... I have pics i can post tomorrow, it is nothing fancy, nipple with a coupler and thread lock in the cap.

The firewall pipe is 2ft, the other is 15". I originally had the other 9" end of the shorter pipe along the firewall and played with the airbox. I think the exhaust is now the throttle so to speak on the torque, the y-pipe stinks and is cut down a lot as it crosses the trans & transfer case area.

I am planning to make a new y-pipe in such a way as to adjust flow at the collector just before the cat.

[steve05ram360]

pics... I used thread sealant on the mating threads, since I'm not done with it, I have not sealed it all up yet. will use pvc sealant on the ends when I'm done and pressure check it.