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3rd Gen Ram Tech2002-2008 Rams: This section is for TECHNICAL discussions only, that involve the 2002 through 2008 Rams Rams. For any non-tech discussions, please direct your attention to the "General discussion/NON-tech" sub sections.
Thought provoking discussions can lead to ah-ha moments... most zero in on the max gains and dont think about the driving experience... which is at part throttle.
yep and common sense prevails evermore. enjoy your journey sir !!!!!!!!!!!!!!!!!!
yep and common sense prevails evermore. enjoy your journey sir !!!!!!!!!!!!!!!!!!
So far this discussion has led to reading studies on helmoltz resonators & how they effect performance (reflective pressure wave back into the intake runner) & intake tube design (in front of the throttle body) and its effect.
Thought provoking discussions can lead to ah-ha moments... most zero in on the max gains and dont think about the driving experience... which is at part throttle.
The 5HP loss with the spacer on a 4.7L was ALL THE WAY ACROSS THE RPM RANGE! It lost everywhere! This is a closed case as far as I am concerned... Iv been building engines to long and have literally watched spacers lose HP on more than one application. Again, no two engines are alike, spacers are best used for tuning Carburated or TBI applications. But they have zero place on a Multi Port Fuel injected engine.
Years ago, I used to go to every DYNO day which as held on the last weekend of every month. I watched guys pull up with their newly modded trucks hoping to best their last DYNO run from last month. It was not uncommon for some of these guys to jump on the DYNO after adding a throttle body spacer... and like clock work, they did not make the power they where expecting... After some chatting, they decided to remove the spacer and try again... Low and behold, 4-5HP gain across the RPM range.
With that said, these same people claimed to have felt the power gain from the spacer... so what happened? Its called the "Placebo effect"! 4-5 HP is very difficult to feel... BUT non the less a loss is a loss and a gain is a gain.
You would better spend your time on a 70MM throttle body, HO or 2008+ CAMs, ATI Superdamper with 25% underdrive pulley, Balanced fuel injectors, installing an electric fan... All these mods are DYNO proven to not only gain you HP but MPG as well. Heck, just insulating your fuel rail is worth 15HP...
My 4.7L had nearly every bolt on mod you could add to the 4.7L to include ported heads and custom tuning. In a 2002 Dodge Ram Quad Cab, i was able to average over 22MPG over 3 tanks of gas.
Heck I towed a 7500lb trailer from DFW to Miami and averaged just over 10.5MPG... now to put this into perspective, the trailer and truck weighed in on a truck scale at 11,525lbs... The MPG would have been better if the wife and dogs could sit through a full tank of gas, so every tank had several stops... and most of the fuel was consumed getting back on to the freeway and driving around truck stops.
If your looking for cheap mods that work:
Insulating your Fuel rail +15
Insulating the bottom of your intake manifold +10ish
FRAM-HP1 Oil filter- Not sure what its worth HP wise however, if you take this filter and hold it up to the factory recommended filter you will see a HUGE difference in oil flow holes. Larger holes mean less restriction/HP loss on the oil pump. This was a secret I ran for years and my truck was always a little quicker than a similar modded truck. My truck was thought to have been a "Factory Freak"... But it was those free mods that gave me a slight advantage.
I'm just trying to answer your questions "As a matter of fact" based on first hand experience. Do what you like with the advice and information... its your truck, you should do what makes you happy. If you have any questions or concerns please dont hesitate to contact me. I am always willing to help customers reach their performance goals wither its towing, MPG or racing.
The 5HP loss with the spacer on a 4.7L was ALL THE WAY ACROSS THE RPM RANGE! It lost everywhere! This is a closed case as far as I am concerned... Iv been building engines to long and have literally watched spacers lose HP on more than one application. Again, no two engines are alike, spacers are best used for tuning Carburated or TBI applications. But they have zero place on a Multi Port Fuel injected engine.
Years ago, I used to go to every DYNO day which as held on the last weekend of every month. I watched guys pull up with their newly modded trucks hoping to best their last DYNO run from last month. It was not uncommon for some of these guys to jump on the DYNO after adding a throttle body spacer... and like clock work, they did not make the power they where expecting... After some chatting, they decided to remove the spacer and try again... Low and behold, 4-5HP gain across the RPM range.
With that said, these same people claimed to have felt the power gain from the spacer... so what happened? Its called the "Placebo effect"! 4-5 HP is very difficult to feel... BUT non the less a loss is a loss and a gain is a gain.
You would better spend your time on a 70MM throttle body, HO or 2008+ CAMs, ATI Superdamper with 25% underdrive pulley, Balanced fuel injectors, installing an electric fan... All these mods are DYNO proven to not only gain you HP but MPG as well. Heck, just insulating your fuel rail is worth 15HP...
My 4.7L had nearly every bolt on mod you could add to the 4.7L to include ported heads and custom tuning. In a 2002 Dodge Ram Quad Cab, i was able to average over 22MPG over 3 tanks of gas.
Heck I towed a 7500lb trailer from DFW to Miami and averaged just over 10.5MPG... now to put this into perspective, the trailer and truck weighed in on a truck scale at 11,525lbs... The MPG would have been better if the wife and dogs could sit through a full tank of gas, so every tank had several stops... and most of the fuel was consumed getting back on to the freeway and driving around truck stops.
If your looking for cheap mods that work:
Insulating your Fuel rail +15
Insulating the bottom of your intake manifold +10ish
FRAM-HP1 Oil filter- Not sure what its worth HP wise however, if you take this filter and hold it up to the factory recommended filter you will see a HUGE difference in oil flow holes. Larger holes mean less restriction/HP loss on the oil pump. This was a secret I ran for years and my truck was always a little quicker than a similar modded truck. My truck was thought to have been a "Factory Freak"... But it was those free mods that gave me a slight advantage.
I'm just trying to answer your questions "As a matter of fact" based on first hand experience. Do what you like with the advice and information... its your truck, you should do what makes you happy. If you have any questions or concerns please dont hesitate to contact me. I am always willing to help customers reach their performance goals wither its towing, MPG or racing.
SPEED SAFE, AIR RAM PERFORMANCE
I appreciate your continued conversation... It helps to open the eyes on what is really going on. So lets drop the TBS and focus on the 70mm TB install... Immediately after the install on the 1st drive, saw a bottom end loss and a mid-range gain (mods at this time were a fuel rail wrap and removed air box snorkle, stock everywhere else). Knowing the ECU needs time to adapt I just made some mental notes of how it was running and motored on. Fast forward 200~300ish miles and the bottom end crept up and cant say I noticed much change on the mid range but was not zeroed in on it.
Question is, what is happening to the AFR in those 200~300 miles while the ECU adapts? So I did a search to se what a non-adaptive setup did with AFR & power output and found a forum thread where the guy was tweeking his AFRs for the most power, he posted the dyno plot below... I want to say it was a porche 928, I did not read the entire thread, here it is if anyone is interested... https://rennlist.com/forums/928-foru...-on-hp-tq.html
So what happens when the bigger TB is installed, now for any given throttle opening the airflow into the manifold now = 68mm + (70-68 airflow change) which now changes the AFR until the ECU adapts to the change.
So now go back to the TBS removal, ECU is adapted to run with the TBS installed, dyno run event to establish baseline. TBS is removed, now on next dyno run more airflow because the disruption in airflow is removed with the TBS so now the AFR goes leaner & hp goes up (according to the above dyno).... until the ECU adjusts to the new flow.
With all that said, unless I missed something in there, it makes sense now to me that you see a bump in hp when removing the TBS. AFR changed and ECU has not adapted to the change in airflow. Once the adaptation takes place, now more fuel dumped to match the airflow & get the AFR back in check.
So what happens to manifold pressure for the 70mm TB vs 68mm?
@AIR_RAM you said you were done so dont feel obligated to continue... I appreciate your input. Thanks.
Wide Open Throttle (WOT) With the engine running, the PCM spark–advance and fuel pulse–width programs are affected during WOT conditions. The PCM is programmed to go into open loop anytime the TPS voltage exceeds 2.7 volts (80% throttle blade) above minimum idle. This enables the PCM to enrich the air/fuel ratio at WOT to allow the combustion chamber to run a little cooler.
The values stored in Long–Term Adaptive Memory are used for all operating conditions, including open loop. However, updating Long–Term Memory occurs after the engine has exceeded approximately 170° F, with fuel control in closed loop and two minutes of engine run time. This is done to prevent any transitional temperature or start–up compensations from corrupting Long–Term Fuel Correction.
So to wrap the fuel rail... what product are you guys using? Pics?
Since 1st jumping on this band wagon way back in 2001, I've used DEI thermal tape https://www.designengineering.com/co...e-tape-2-x-30/ which proved to work excellent but was a PITA to install. Starting with the R53 mini I had before the Dak, I decided to experiment with exhaust wrap https://www.heatshieldproducts.com/i...hield-products I cut a chunk of this stuff, dropped it on a small sheet of sheet metal and hit it for a good long time with a heat gun, then pulled the piece and looked at it with a thermal cam. Looked good to me so installed it with success on the R53. Found similar success on the Dak. Way easier to install, easy to remove and plan to re-do it when I yank the rails for new 4 hole injectors.
Last edited by steve05ram360; Jan 23, 2022 at 08:58 AM.
So far this discussion has led to reading studies on helmoltz resonators & how they effect performance (reflective pressure wave back into the intake runner) & intake tube design (in front of the throttle body) and its effect.
These 2 pics say a lot...
Reviving this thread to share some lessons learned... truck is the 2002 QC 4x4 dakota with the 4.7 engine, the heaviest there is with 3.55's and 265-75/16 E rated tires.
Experimented with adding a couple of things... 1st was the install of a turning vane on the inside of the intake tube. This vane gave a very noticeable SOTP bump in power across all rpms used. Took this mod from the Ram CTD list of mods done on my truck... had the same effect there as well. 2nd was the addition of some vacuum reservoirs off the intake manifold. The 1st stab at it I pulled the turning vane to see the effect on performance by itself. Very noticeable SOTP bump in power down in the lower rpm range. Upper (for where I use it, max approx 3500 rpms) did not show as great of a bump in performance as the bottom end. I then added back the turning vane and again found more power everywhere I used it but, bottom end dropped off a bit, noticeably. So I played with it more by adding more capacity with the 2nd tube and to my surprise, bottom end came back. I concluded that I could put the torque peak pretty much anywhere in the 1500-3000 rpm range by adjusting the size of the added tubes (1.5" by 2'). Being greedy I then pulled the intake snorkle off the air box expecting the torque to jump up rpms once again and sure enough, it did. Today I should get a 2.5" vacuum exhaust cutout to add to the air box to get the best of both worlds of bottom end torque and better mid range power when on it harder... same mod I did to the Rams air box but with boost. Fuel trims are still as expected, with the turning vane alone they showed more fuel being dumped, with both, it moved more towards what would be normal. Been running this for about a month, 1200~1500 miles and no issues, just good bit of added power.
MPGs have gone from the 15-upper 16 range (17's were a stretch) to the 19-20 mpg range while keeping the speeds consistent on the work commute.
Turning vane for intake tube installed @ the 90* bend.
Engine as it sits with 2 added 1.5" tubes off vacuum lines attached to the IM.
