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Discussion Starter · #1 ·
I finally got down to the dyno after installing my super B and valair dd this winter. Previously I hit 320/680 on stock turbo with 150 sticks with the edge off. With the super b and clutch added, it bumped that up to 354/717. Before with the edge on and 150 sticks on stock turbo I hit 387/816 and after turbo/clutch I hit 422/802. Max temp was 1350-1400 and boost was 43-45. I made several runs while playing with the edge from 5x1-5x5 and every level made almost identical power (varied + or - 4 on hp/tq). I don't think the turbo can handle the fuel on the higher fueling levels. I know that my wire tap is good because on 5x1 we didn't have to clear out the shop after the run but on 5x5 with 2 huge exhaust fans running we still had to vacate the shop for 5mins. I'm happy that I gained 35hp, but dissapointed that I lost 20tq. I'm assuming that it's because the super b has a larger exhaust housing and allows more flow out the exhaust with less restriction than stock which helps hp but shouldn't that help tq as well? I'm happy with my results using this turbo, but think that I need something a little larger (R700 Twins:drool2:followed by monster pump:shock:)to burn the extra fuel. If someone could give me some insight on my torque # drop it would be appreciated.
 

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when you spool whats your exhaust? clean, hazzy or black
 

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Discussion Starter · #5 ·
It definitely spools very fast. 1500-1800rpm i get my 10psi depending on how I go into the throttle and its a split second from 10-45psi. At wide open throttle there is still a bit of a haze but not billowing clouds. I didn't go with the special because I want to go with a set of quick spooling twins (R700) eventually and the special would mean that I would have to go with a huge twin setup(R850) that would be pretty laggy. Eventually I would like to go with a monster or bd pump to try and get 600hp on fuel only and then 700ish with some giggle juice.
 

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i made 409/743 with quadzilla, 90 sticks, 4" exhaust, valair single disk ceramic clutch, and stock turbo...

I was also running stock air intake and air filter all still connected....

it really seems to me your numbers should be higher than that...


on your loosing torque issue... more timing = more horsepower and less torque.
 

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torque is really an irrelivant number when it comes to performance. thats how much force it can apply to a load (transmission) at any given time. horsepower is how much torque is applied over the given time. the reason why a diesel has higher torque numbers than hp numbers is because it revvs so low, whereas a 8k redline 4 cyl has higher hp than torque, is cause it revvs so high. 500 hp throws you back in your seat, regardless of how much torque there is.

thats my theory! or understanding of it. please correct me if im wrong
 

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Discussion Starter · #8 ·
i made 409/743 with quadzilla, 90 sticks, 4" exhaust, valair single disk ceramic clutch, and stock turbo...

I was also running stock air intake and air filter all still connected....

it really seems to me your numbers should be higher than that...


on your loosing torque issue... more timing = more horsepower and less torque.
I've heard that before, but I'm running the same timing as last time I dynoed but I got 20tq less. The turbo isn't cleaning all of the fuel up on the top end and I'm hitting 45psi so I don't think lack of fuel is my problem even though its a HO pump. BD rates this turbo for 425hp but I figured with the fuel I was running I could squeeze past that a bit. I was hoping this turbo would be big enough for a bit, but its time to go bigger.
 

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I've heard that before, but I'm running the same timing as last time I dynoed but I got 20tq less. The turbo isn't cleaning all of the fuel up on the top end and I'm hitting 45psi so I don't think lack of fuel is my problem even though its a HO pump. BD rates this turbo for 425hp but I figured with the fuel I was running I could squeeze past that a bit. I was hoping this turbo would be big enough for a bit, but its time to go bigger.
thats my point... im on smaller turbo (stock) and smaller injectors and im not far from you.

and bighorn torque isnt too irrelevant, as with 0 torque and 10,000 horsepower your truck would never move.
torque
"Mechanics. something that produces or tends to produce torsion or rotation; the moment of a force or system of forces tending to cause rotation."

"Machinery. the measured ability of a rotating element, as of a gear or shaft, to overcome turning resistance."

so basically it is what gives you the ability to turn the drive train to get it all moving

horsepower is exactly what it sounds like

"1806, from horse + power, established by Watt as the power needed to lift 33,000 pounds one foot in one minute, which is actually about 1.5 times the power of a strong horse."

"A unit that is used to measure the power of engines and motors. One unit of horsepower is equal to the power needed to lift 550 pounds one foot in one second. This unit has been widely replaced by the watt in scientific usage; one horsepower is equal to 745.7 watts."

so the torque spins it all the horsepower enables it to move a little faster. it really has nothing to do with the rpms of the engine.

diesels make more torque because the fuel has more stored energy than gasoline

if you compare a 4 banger diesel to a 4 banger gasser on an equal chassis the offset by one will on tq will be made up by hp and vise versa.
 

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torque to me is more important when pulling... i agree you have to make torque but thats a givin.. if your makin horsepower you are therefore making torque.. Torque is not as important as horsepower when it comes to being fast tho.. if your running it to red line then shifting your not going to be hitting your peak torque anyways... Torque is harder on the tranny tho... Thats why The D MAX guys have it good with EFI Live... They can tune their trucks to not make more than 1000 lbs of torque, which is about all the allison really can handle without major upgrades, but still tune for horsepower..
 

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Check your IATs, I think 45 psi is a little out of the efficiency range of the Super B unless if you are referring to the special, if it's the regular one you are probably blowing hot air which doesn't help at all and can be hurting you. It's just a thought.

Also I see torque as HP=(torque*rpm)/5252 lol I am Mr. Obvious. :buttkick:
 

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Discussion Starter · #12 ·
Check your IATs, I think 45 psi is a little out of the efficiency range of the Super B unless if you are referring to the special, if it's the regular one you are probably blowing hot air which doesn't help at all and can be hurting you. It's just a thought.

Also I see torque as HP=(torque*rpm)/5252 lol I am Mr. Obvious. :buttkick:
I was talkin with Dave from BD and he said that max efficient boost for the super b single was 45psi and I'm hovering in the 42-45. It will spike to 45 when it spools, then it settles at around 43ish for the rest of the run. That will be my last dyno run until I get my head work done, and then I will be looking at twins so that should solve my problems. As is, my head gasket isn't liking me. I have a small coolant leak out the front, right above the water pump that needs my attention. Thankfully it's not getting into the oil and its holding strong so far, so I can still drive it but its time to remedy it. I'm just waiting for the CDN $ to gain on the American $ a little more so that my parts are a bit cheaper.:hehe:
 

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That little compressor wheel is not much more efficient than the stocker IMO.

The benefit comes from the rear of the turbo. It definitely flows better and has better boost control.

I would not have suggest the Special either. Being a 62/ 71 size charger, it would not be the first choice for what you are saying with twins use anyway. Especially if you are going to run a S400 under it.

Now, we did help the shop truck spool much better with a different bottom charger.

It has a HTT 64/65-13 and was a slow spooler with the tight auto and the S400. Swapped a K31 for the S400 and it lights WAY faster. HP is almost the same, but spool is crazy fast.

So, even with twins, that little Super B is still going to be challenged.

Dave
 

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Discussion Starter · #14 ·
That little compressor wheel is not much more efficient than the stocker IMO.

The benefit comes from the rear of the turbo. It definitely flows better and has better boost control.

I would not have suggest the Special either. Being a 62/ 71 size charger, it would not be the first choice for what you are saying with twins use anyway. Especially if you are going to run a S400 under it.

Now, we did help the shop truck spool much better with a different bottom charger.

It has a HTT 64/65-13 and was a slow spooler with the tight auto and the S400. Swapped a K31 for the S400 and it lights WAY faster. HP is almost the same, but spool is crazy fast.

So, even with twins, that little Super B is still going to be challenged.

Dave
Is the K31 a ball bearing turbo? I thought that going from a 54mm-a 57mm extended tip compressor wheel would have helped more than that, but I have learnt different. My thoughts on the twins were that the 14cm exhaust on the super b should allow for enough flow for high HP with a decent sized primary. Wouldn't the super B allow for quick spool, then when the wastegate opens allow the primary to do its thing or will the compressor side of the super b be too restrictive for the primary to flow through??? thanks for all of the info.
 

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Is the K31 a ball bearing turbo? I thought that going from a 54mm-a 57mm extended tip compressor wheel would have helped more than that, but I have learnt different. My thoughts on the twins were that the 14cm exhaust on the super b should allow for enough flow for high HP with a decent sized primary. Wouldn't the super B allow for quick spool, then when the wastegate opens allow the primary to do its thing or will the compressor side of the super b be too restrictive for the primary to flow through??? thanks for all of the info.
No, the K31 is not. And it would be best to run this with a 64mm sized secondary anyway. Just for better spooling. The typical S480 would be for the guys running massive fueling, drag racing, sled pulling. Most VPs cannot keep up with that combo.

The turbine side won't be much of an issue unless you are running stupid fuel. So, drive pressures should be able to be kept on check.

The issue is compounding the charge air side. With a wheel that small, and even with a larger bottom charger it's only gonna get so good. In other words, you will have to push the top turbo harder than you would with say a 62mm charger to get the same net effect. This raises temps, drive pressures obviously and is generally less effective than a slightly larger secondary.

Can you do it and will it work? Yes. It will just have some upper mid to high end limitations.

It'll probably dyno lower than you like, never get very hot and still run a number at the track that does not compute to a dynojet number. Just the way it is.


Dave
 

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I have the same setup as you. But i have 100hp injecctors and a smarty with an auto. Mine made 400hp and 870 of torque. I also plan on running a twin setup with my super b and a S400. So i hope it will work out
 

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torque is really an irrelivant number when it comes to performance. thats how much force it can apply to a load (transmission) at any given time. horsepower is how much torque is applied over the given time. the reason why a diesel has higher torque numbers than hp numbers is because it revvs so low, whereas a 8k redline 4 cyl has higher hp than torque, is cause it revvs so high. 500 hp throws you back in your seat, regardless of how much torque there is.

thats my theory! or understanding of it. please correct me if im wrong
i have to say your wrong when you say torque is an irrelivant number when pulling. If anything its more important i think because you have more "lug". And i have always been told by tractor pullers that hp numbers are strictly based off torque levels and that hp doesnt really exist its a numerical figure.
 

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i have to say your wrong when you say torque is an irrelivant number when pulling. If anything its more important i think because you have more "lug". And i have always been told by tractor pullers that hp numbers are strictly based off torque levels and that hp doesnt really exist its a numerical figure.
Exactly! HP=(torque*RPM)/5252 so if there is no torque there's no HP. If you're making more torque than someone else at the same RPM then you're making more HP at the same RPM.
 

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Discussion Starter · #20 ·
There were 3 changes that I made to my truck after the last time I dynoed to help improve for this time. clutch/turbo/drag upgrade for comp. The clutch is allowing me to hold all the power perfectly so it's doing its job. I'm fueling harder at higher rpms so thats giving me my torque at higher rpms which translates into more hp. What the hell is the turbo doing then??? It spools great, but if I stay into it long enough the egts will climb pretty high which doesn't surprise me with 150 sticks. If it does flow more air than the hx35, wouldn't that have shown up on the dyno with it burning more of my fuel=more torque??? Thanks for all of the input so far.
 
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