Builds Big Red Toy (7 Viewers)
- Thread starter The Phoenician
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- #3,002
The most smoke is at the low end of the rpm range when accelerating. Then it goes a bit hazy then almost clears up.
Some thoughts:
Basically two sides to tuning. Fuel delivery and/or air delivery.
For fueling it sounds like it'll be more tuning on how to add fuel as boost is building since the smoke clears under full boost and the EGTs are back to the 1200F range. Those delivery valves definitely give you more fuel so that's a change in the system. Hopefully they don't make it too tricky to get to your just right spot. I'm not too familiar with the P pump but I know there are different fuel plates you can play with. Might want to stick with a mild plate with a mild fuel ramp (since your delivery valves are adding more fuel anyways) and look into tightening up any AFC settings (more preload or stiffer spring so it takes more boost before adding more fuel). The spring for my AFC control was not strong enough since I'm building way more boost than it was originally designed for. I ended up using a boost control valve (boost fuller) in the signal line going to my Injection pump AFC to give me some more control so it doesn't overfuel so quickly. Gives the turbos more time to spool up before adding more fuel and with more air there should be less black smoke.
For the air side we deal with spooling. Do you know when your small turbo's wastegate is opening? If it's a little laggy you may need to tighten the small turbo's wastegate so it gets spinning more before sending more exhaust energy to the large turbo. I cannot see a boost reference line hooked up to the large turbo but in order to play with the formulas to see how each turbo is contributing you'll need a total boost and a large turbo boost reading. Since you swapped out your main gauge (now your total boost gauge) you could use your old one to get a reading from the large turbo. It looks like there is a port on the large compressor housing already which would be the ideal spot to reference your large turbo's boost. Plug it in the formula to find out what the little turbo is doing. Knowing how each turbo is contributing to the total boost will help you see what different adjustments will do.
Basically two sides to tuning. Fuel delivery and/or air delivery.
For fueling it sounds like it'll be more tuning on how to add fuel as boost is building since the smoke clears under full boost and the EGTs are back to the 1200F range. Those delivery valves definitely give you more fuel so that's a change in the system. Hopefully they don't make it too tricky to get to your just right spot. I'm not too familiar with the P pump but I know there are different fuel plates you can play with. Might want to stick with a mild plate with a mild fuel ramp (since your delivery valves are adding more fuel anyways) and look into tightening up any AFC settings (more preload or stiffer spring so it takes more boost before adding more fuel). The spring for my AFC control was not strong enough since I'm building way more boost than it was originally designed for. I ended up using a boost control valve (boost fuller) in the signal line going to my Injection pump AFC to give me some more control so it doesn't overfuel so quickly. Gives the turbos more time to spool up before adding more fuel and with more air there should be less black smoke.
For the air side we deal with spooling. Do you know when your small turbo's wastegate is opening? If it's a little laggy you may need to tighten the small turbo's wastegate so it gets spinning more before sending more exhaust energy to the large turbo. I cannot see a boost reference line hooked up to the large turbo but in order to play with the formulas to see how each turbo is contributing you'll need a total boost and a large turbo boost reading. Since you swapped out your main gauge (now your total boost gauge) you could use your old one to get a reading from the large turbo. It looks like there is a port on the large compressor housing already which would be the ideal spot to reference your large turbo's boost. Plug it in the formula to find out what the little turbo is doing. Knowing how each turbo is contributing to the total boost will help you see what different adjustments will do.
- Thread starter
- #3,004
The plan was to install two gauges, but time did not permit. I still have the old gauge.
Been concerned with some electrical issues and this oil leak. The starter did not immediately engage today, but eventually worked. The pyro is erratic, but eventually settles down. I'm curious to see what the mpg is. I'll be happy if it remains the same around 18mpg with mixed driving.
Here's where i found the leaks to be coming from. Will work on it tomorrow.
Update: looks like 17mpg. Not great but considering the power gains, not bad. I hope to gain more once i get it dialed in.
Been concerned with some electrical issues and this oil leak. The starter did not immediately engage today, but eventually worked. The pyro is erratic, but eventually settles down. I'm curious to see what the mpg is. I'll be happy if it remains the same around 18mpg with mixed driving.
Here's where i found the leaks to be coming from. Will work on it tomorrow.
Update: looks like 17mpg. Not great but considering the power gains, not bad. I hope to gain more once i get it dialed in.
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I think that's great considering how big and heavy Big Red is. What were you getting before?
- Thread starter
- #3,006
I was getting 18mpg. Occasionally I'll get a bit more or a bit less depending on head wind or tail wind.
My mileage has come out to about the same 18-20... when I drive it normally. It's not necessarily about having more power that impacts mileage, it's about how you use that extra power. 
The first tanks my mileage dropped because my foot was having too much fun (umm yes, my brain had nothing to do with that) and I'd expect your tuning process to require more fuel as you find the spot you want. Now it's an exercise of will power.
It does look like your main leak is coming from the oil adapter. That seems the most juicy. If I'm seeing it right the small turbo drain looks dry but the large turbo drain does look to have a small streak coming down. Was the oil adapter that goes on the block removed during the turbo fab process? Is something leaking on the top and it's traveling around to the bottom of that adapter?
The first tanks my mileage dropped because my foot was having too much fun (umm yes, my brain had nothing to do with that) and I'd expect your tuning process to require more fuel as you find the spot you want. Now it's an exercise of will power. It does look like your main leak is coming from the oil adapter. That seems the most juicy. If I'm seeing it right the small turbo drain looks dry but the large turbo drain does look to have a small streak coming down. Was the oil adapter that goes on the block removed during the turbo fab process? Is something leaking on the top and it's traveling around to the bottom of that adapter?
- Thread starter
- #3,008
The oil filter was removed or still in its original position on the fender when the pipes were fabbed. I'm going to try to work on it after i get off work. Hopefully it's an easy fix. I need to track where the smoke is coming out and into the cab as well.
I agree with you about the heavy right foot, i suspected my mpg would be lower the first time because I'm trying out the new found power.
I agree with you about the heavy right foot, i suspected my mpg would be lower the first time because I'm trying out the new found power.
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- #3,009
I guess it's update time. I didn't do much other than tightening the oil line clamps and sealing the firewall with foam. No more smoke in the cab 
.
I drove from Georgetown to Fort Worth with the front hubs locked, most of the drive was highway miles. So I'm convinced Big Red now has more horsepower than our new Tacoma. I drove mostly between 70 and 77 mph and at some points, I took it to 83mph. I'm sure I could have gone faster, but it's scary at that speed and it doesn't slow down as fast as I'd like it to. EGTs were between 900 and 1100 and boost averaged at around 14psi. I hooked up my methanol pump and set it at around 18psi. As far as I can tell, it doesn't cool the EGTs but it does boost power. I'm able to overtake vehicles easily and get out of the way quickly if need be. The best part, I averaged 19.5 mpg. I'm not sure if this is a fluke so I'll see what I get on Sunday on my way down, hopefully, there won't be any traffic. I also ordered a larger intercooler, 27X12X3 with a 2.5 inlet and outlet. My current one is 27X7X2.5.
I will probably start messing with the wastegates next. Thinking of closing the small turbo wastegate and going from there. I'm not sure how much tinkering I want to do with the pump since it's a big improvement in performance already. I'll keep updating as new figures come in.
.I drove from Georgetown to Fort Worth with the front hubs locked, most of the drive was highway miles. So I'm convinced Big Red now has more horsepower than our new Tacoma. I drove mostly between 70 and 77 mph and at some points, I took it to 83mph. I'm sure I could have gone faster, but it's scary at that speed and it doesn't slow down as fast as I'd like it to. EGTs were between 900 and 1100 and boost averaged at around 14psi. I hooked up my methanol pump and set it at around 18psi. As far as I can tell, it doesn't cool the EGTs but it does boost power. I'm able to overtake vehicles easily and get out of the way quickly if need be. The best part, I averaged 19.5 mpg. I'm not sure if this is a fluke so I'll see what I get on Sunday on my way down, hopefully, there won't be any traffic. I also ordered a larger intercooler, 27X12X3 with a 2.5 inlet and outlet. My current one is 27X7X2.5.
I will probably start messing with the wastegates next. Thinking of closing the small turbo wastegate and going from there. I'm not sure how much tinkering I want to do with the pump since it's a big improvement in performance already. I'll keep updating as new figures come in.
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- Thread starter
- #3,010
Electrical gremlins are plaguing me. I thought I burned out the starter last night. It started to turn then abruptly stopped and wouldn't crank again.
Today to get home I had to get 4 enlisted Sailors to help me push start Big Red to get it to run. I popped the clutch when I got it going to 2mph in reverse, it started right up. On my way down I had made good time most of the way and got it going to 85mph at one section. Some Raptor tried to race me but got bored when I wouldn't compete with him. We ended up doing most of the 175 mile drive together. I found that the sweet spot for Big Red is between 75 and 77 mph, it's at about 2k RPM and EGT under 1000*.
A cool front had set in and my motor temp was a constant 190* except for one section and I cruised with EGTs at around 900* unless I was accelerating hard. There was a stretch of road with massive slowdowns, so It's not exactly apples to apple comparison with Friday's drive. Despite this, I still managed 18.5 mpg.
When I got home I shut it off but when I turned it back on, the starter cranked and started the engine. Not sure what's up but I already ordered a Denso starter. My switch may be acting up or I need to tighten the connections. Either way, I hate electrical issues.
Today to get home I had to get 4 enlisted Sailors to help me push start Big Red to get it to run. I popped the clutch when I got it going to 2mph in reverse, it started right up. On my way down I had made good time most of the way and got it going to 85mph at one section. Some Raptor tried to race me but got bored when I wouldn't compete with him. We ended up doing most of the 175 mile drive together. I found that the sweet spot for Big Red is between 75 and 77 mph, it's at about 2k RPM and EGT under 1000*.
A cool front had set in and my motor temp was a constant 190* except for one section and I cruised with EGTs at around 900* unless I was accelerating hard. There was a stretch of road with massive slowdowns, so It's not exactly apples to apple comparison with Friday's drive. Despite this, I still managed 18.5 mpg.
When I got home I shut it off but when I turned it back on, the starter cranked and started the engine. Not sure what's up but I already ordered a Denso starter. My switch may be acting up or I need to tighten the connections. Either way, I hate electrical issues.
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Love it man. Nice work 
Can't wait till I have moonshine up again with an intercooler.
Can't wait till I have moonshine up again with an intercooler.
Adjust star wheel towards engine a couple clicks at a time until it starts to clear, sounds like your fuel plate is pretty close based on your total EGT’s so I wouldn’t move it just yet.
If it’s giving you a puff of smoke just off idle you might need to back off your pre-boost screw on the back of the AFC.
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- #3,013
While I'm waiting on parts to come in
Also waiting on a mount for the boost gauge.
Also waiting on a mount for the boost gauge.
- Thread starter
- #3,014
Mounted the new intercooler. Very snug fit, but it fits.
Ended up blowing a boot at 25psi. Had to delete the methanol injection pump and change out a few bends to make it fit and work. Tomorrow i hope to change out the starter.
Ended up blowing a boot at 25psi. Had to delete the methanol injection pump and change out a few bends to make it fit and work. Tomorrow i hope to change out the starter.
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- #3,015
Drove it around all morning. Had the second turbo gauge installed so I can compare the difference in boost from the larger turbo and the final psi number. It's hard to tell if there is a constant difference or not since I don't trust the new gauge, but it looks like when I'm doing 10 on the compound gauge it's reading 4psi on the large turbo gauge. I don't have it mounted in a permanent spot at the moment so it's wedged between the windshield and the dash for now.
I think it's safe to say my wastegate opens at around 30psi. I can get there quickly, but then it's labor-intensive to go higher and maintain anything above 35psi. I think eventually I will weld it shut. Right now I'm trying to see if the couplers will hold that kind of pressure. On my test run, there was this older lady (60s) driving a pick up with her dog give me the eye then the thumbs up. So I guess I'm doing something right?
Here's what it looks like from the front with the new intercooler. It's not exactly centered, but that's the only way it will fit flush.
EDIT: After driving it for a while I guess I can say the intercooler works. On one end you can fry an egg because how hot it is, but on the other end, it's really cool to the touch.
I think it's safe to say my wastegate opens at around 30psi. I can get there quickly, but then it's labor-intensive to go higher and maintain anything above 35psi. I think eventually I will weld it shut. Right now I'm trying to see if the couplers will hold that kind of pressure. On my test run, there was this older lady (60s) driving a pick up with her dog give me the eye then the thumbs up. So I guess I'm doing something right
?Here's what it looks like from the front with the new intercooler. It's not exactly centered, but that's the only way it will fit flush.
EDIT: After driving it for a while I guess I can say the intercooler works. On one end you can fry an egg because how hot it is, but on the other end, it's really cool to the touch.
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- Thread starter
- #3,016
I forgot to post this video last weekend. It was on my way to drill, in the video I go up to 76mph according to the gps. This was with the smaller intercooler, so I'm curious to see how it does with the larger one.
- Thread starter
- #3,017
Larger intercooler seems to be working well. Cruised the highway at 75mph loaded with my kayak and 3 bicycles, EGTs we're between 880 and 950. At one point I decided to floor the pedal, managed to get above 45 psi and you can really hear the turbo whine, but i had to back off as the EGTs hit 1400.
There seems to be a 10 psi difference between the larger turbo and the pressure at the intake manifold.
There seems to be a 10 psi difference between the larger turbo and the pressure at the intake manifold.
Does the new intercooler seem to give you lower EGTs?
Good, now we can see how the two turbos are sharing the load with having your total and big turbo boost gauges. Let's shove your numbers into the formula to see what's going on.
Formula (you have to turn psi numbers in to pressure ratios to see what's going on, we then convert back to psi to help understand what's going on):
PR = (PSIg + At pressure)/At pressure
PR = pressure ratio, PSIg = gauge boost pressure reading, At pressure = atmospheric pressure (this changes depending upon your elevation, I'll just use the standard 14.7 because I don't know what your elevation is).
From first readings of 10psi (total) and 4psi (big):
Total PR = (10 + 14.7)/14.7 = 1.68
Primary PR (big turbo)= (4 + 14.7)/14.7 = 1.27
Then take Total PR/Primary PR to get the secondary PR
Secondary PR (small turbo) = 1.68/1.27 = 1.32
Then to get secondary psi work the formula backwards
Secondary (small turbo) psi = (1.32 * 14.7) - 14.7 = 1.3 psi
***So, when your total boost is 10psi your big turbo is making 4 psi and your small turbo is making 1.3 psi.
Now let's look at your max boost readings: Your second reading of 45 psi and 35psi (going off your comment that the big was about 10 less than the total)
Total PR = (45 + 14.7)/14.7 = 4.06
Primary PR (big turbo)= (35 + 14.7)/14.7 = 3.38
Then take Total PR/Primary PR to get the secondary PR
Secondary PR (small turbo) = 4.06/3.38 = 1.20
Then to get secondary psi work the formula backwards
Secondary psi = (1.20 * 14.7) - 14.7 = 2.9 psi
*** When total boost is 45 psi, your large turbo is making 35psi and your small is making 2.9psi.
Your small turbo looks like it is barely doing any work and your big turbo may be close to just making hot air. You need to get the wastegate on the small turbo to open later or in other words keep its wastegate shut longer. You can do this a couple of ways.
1. Tighten the wastegate rod so that there's more tension on the internal spring in the wastegate diaphragm.
2. Add an additional outside spring to add more tension.
3. Insert a boost fooler (boost control valve) to the boost line that runs from your small turbo to your small turbo's wastegate diaphragm.
I have done and am currently running all three of these things together to get the small turbo to keep it's wastegate shut longer. This will have a couple of benefits of faster spool up, cooler egts, and better sharing of the boosting load between the two turbos which will cool off the intake air temp. Do this in steps and watch your gauges so you don't make too much total boost. You can work the above formula's to find out your tuning results. There is a lot more potential in your set up.
Formula (you have to turn psi numbers in to pressure ratios to see what's going on, we then convert back to psi to help understand what's going on):
PR = (PSIg + At pressure)/At pressure
PR = pressure ratio, PSIg = gauge boost pressure reading, At pressure = atmospheric pressure (this changes depending upon your elevation, I'll just use the standard 14.7 because I don't know what your elevation is).
From first readings of 10psi (total) and 4psi (big):
Total PR = (10 + 14.7)/14.7 = 1.68
Primary PR (big turbo)= (4 + 14.7)/14.7 = 1.27
Then take Total PR/Primary PR to get the secondary PR
Secondary PR (small turbo) = 1.68/1.27 = 1.32
Then to get secondary psi work the formula backwards
Secondary (small turbo) psi = (1.32 * 14.7) - 14.7 = 1.3 psi
***So, when your total boost is 10psi your big turbo is making 4 psi and your small turbo is making 1.3 psi.
Now let's look at your max boost readings: Your second reading of 45 psi and 35psi (going off your comment that the big was about 10 less than the total)
Total PR = (45 + 14.7)/14.7 = 4.06
Primary PR (big turbo)= (35 + 14.7)/14.7 = 3.38
Then take Total PR/Primary PR to get the secondary PR
Secondary PR (small turbo) = 4.06/3.38 = 1.20
Then to get secondary psi work the formula backwards
Secondary psi = (1.20 * 14.7) - 14.7 = 2.9 psi
*** When total boost is 45 psi, your large turbo is making 35psi and your small is making 2.9psi.
Your small turbo looks like it is barely doing any work and your big turbo may be close to just making hot air. You need to get the wastegate on the small turbo to open later or in other words keep its wastegate shut longer. You can do this a couple of ways.
1. Tighten the wastegate rod so that there's more tension on the internal spring in the wastegate diaphragm.
2. Add an additional outside spring to add more tension.
3. Insert a boost fooler (boost control valve) to the boost line that runs from your small turbo to your small turbo's wastegate diaphragm.
I have done and am currently running all three of these things together to get the small turbo to keep it's wastegate shut longer. This will have a couple of benefits of faster spool up, cooler egts, and better sharing of the boosting load between the two turbos which will cool off the intake air temp. Do this in steps and watch your gauges so you don't make too much total boost. You can work the above formula's to find out your tuning results. There is a lot more potential in your set up.
- Thread starter
- #3,020
It seems to be cooling on average about 50* so I'm in the 900* range. But it's been cooler here so I'm not sure how much of that is just the weather.
Wow, Thanks for doing the math. I thought it was the larger turbo that's not being used efficiently.
I need to figure out a way to keep it shut, now that I have a baseline for how the truck runs. Maybe make a bracket that holds it in place. It's crazy that it's not even making 3 psi.
