I did the measurements again using a better air pressure gauge.
Diesel Dynamics Spring
Red/ Green Spring
Jay
Diesel Dynamics Spring
Red/ Green Spring
Jay
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AFC Spring Measurements Updated
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Jay,
That's some nice work bud.....
Have you found a "silver" colored spring to try out??
An overlay comparison of them seems to indicate that they are quite similar. Mostly the red/green spring provides a more uniform change as the # of turns goes up, and all end up pretty much the same place. What I'm saying is the spacing between each turn up is nice and uniform pretty much right to the very last. I notice that initial movement with the stock spring is sooner (lower boost).
The DD spring starts later, moves up in uniform amounts based on # of turns, but really flattens out on the 5 and 6 turns up and about 11 psi. In fact the DD spring using 5 and 6 turns never does "peak out" with the rest of the traces in it's group.
Wanting movement and hence, fueling to start a bit later (6/7/8psi) and still have a good upward curve with a "full movement finish" so to speak, it looks like the stock spring using 3-6 turns is the better choice but results in pushing max travel till higher boost levels. This would allow boost to develope more before heavier fueling starts, thus reducing smoke.
Using . 400 as a benchmark for example... . the DD spring hits/breaks that line by the time you reach about 19-20 psi.
The stock spring takes till 25. 5 psi or so.
So the DD spring looks good at 3 turns up
When looking at the measurements of the cone from it's lowest point to it's highest point (throat) the distance is 0. 5210 for the stock cone, and 0. 5073 for the DD cone assembly.
In neither case does the diahpram depress enough to reach what you would call "full travel". The DD spring allows for a max travel of about 0. 415 and the stock allows about 0. 410 travel at max boost. ... ... Hmmmmmm... .....
A lot of guys are running about 25-28 psi so wouldn't we want max fueling to climb nice and uniform and peak out right at peak boost??? Yes/No ???
Now the results/performance will be skewed, in relation to smoke/boost etc, since we have larger injectors, and advanced timing.
Ok guys, check my reasoning since it's late and I'm pretty tired, I may have it all bass ackwards.
Geezz, this doesn't even take into account the effects of tweaking the full fuel screw, OR the smoke screw either... .
I got a headache.....
Oh on another point, I went out today and installed my 14cm NW housing. It took some doing to convince the exhaust downpipe that it should move back but after using highly technical language, donating some blood to the turbo god, and a wide array of unconventional tools, it went on.
The 16cm slipped off so sweet it was embarrassing. Use anti-sieze when you work on those things and they come off smooth as silk.
Also on the spec plate on the side of the engine the pump is rated at 74cc's per/1000 strokes if I read it right. Thats CPL 1579
I mention this since it relates to the thread that dzlpwr was posting in when we were trying to figure out "stock" volume amounts.
Bob.
That's some nice work bud.....
Have you found a "silver" colored spring to try out??
An overlay comparison of them seems to indicate that they are quite similar. Mostly the red/green spring provides a more uniform change as the # of turns goes up, and all end up pretty much the same place. What I'm saying is the spacing between each turn up is nice and uniform pretty much right to the very last. I notice that initial movement with the stock spring is sooner (lower boost).
The DD spring starts later, moves up in uniform amounts based on # of turns, but really flattens out on the 5 and 6 turns up and about 11 psi. In fact the DD spring using 5 and 6 turns never does "peak out" with the rest of the traces in it's group.
Wanting movement and hence, fueling to start a bit later (6/7/8psi) and still have a good upward curve with a "full movement finish" so to speak, it looks like the stock spring using 3-6 turns is the better choice but results in pushing max travel till higher boost levels. This would allow boost to develope more before heavier fueling starts, thus reducing smoke.
Using . 400 as a benchmark for example... . the DD spring hits/breaks that line by the time you reach about 19-20 psi.
The stock spring takes till 25. 5 psi or so.
So the DD spring looks good at 3 turns up
When looking at the measurements of the cone from it's lowest point to it's highest point (throat) the distance is 0. 5210 for the stock cone, and 0. 5073 for the DD cone assembly.
In neither case does the diahpram depress enough to reach what you would call "full travel". The DD spring allows for a max travel of about 0. 415 and the stock allows about 0. 410 travel at max boost. ... ... Hmmmmmm... .....
A lot of guys are running about 25-28 psi so wouldn't we want max fueling to climb nice and uniform and peak out right at peak boost??? Yes/No ???
Now the results/performance will be skewed, in relation to smoke/boost etc, since we have larger injectors, and advanced timing.
Ok guys, check my reasoning since it's late and I'm pretty tired, I may have it all bass ackwards.
Geezz, this doesn't even take into account the effects of tweaking the full fuel screw, OR the smoke screw either... .
I got a headache.....
Oh on another point, I went out today and installed my 14cm NW housing. It took some doing to convince the exhaust downpipe that it should move back but after using highly technical language, donating some blood to the turbo god, and a wide array of unconventional tools, it went on.
The 16cm slipped off so sweet it was embarrassing. Use anti-sieze when you work on those things and they come off smooth as silk.
Also on the spec plate on the side of the engine the pump is rated at 74cc's per/1000 strokes if I read it right. Thats CPL 1579
I mention this since it relates to the thread that dzlpwr was posting in when we were trying to figure out "stock" volume amounts.
Bob.
Jay,
As a follow-up to my last post above, I have a question based on your results.
I believe you posted the pic w/dimensions of the DD and Stock AFC cones in another post.
That post explained that the 'base to throat' distance was:
0. 5073" for the DD cone and the deflection test with their kit resulted in max deflection of 0. 415"
0. 5210" for the Stock cone and the deflection test with the stock is 0. 410".
So either the guide pin is starting out up from the bottom of the cone and travelling to the throat... . OR the guide pin is starting out at max bottom and not travelling right up to the throat of the cone. . Any thoughts on this??
In both your test procedures, neither one resulted in the guide pin making max travel based on the deflection(s) you demonstrated.
edit: Never mind, I think I figured out the discrepancy... it's the spacer washer. . ???
Is there something that is going wrong? Is this normal?
I think that utilizing "full" travel on the cone, with the guide pin is what we are aiming for, among other things. Yes/No ????
Am I on the right/wrong track here???
Bob.
As a follow-up to my last post above, I have a question based on your results.
I believe you posted the pic w/dimensions of the DD and Stock AFC cones in another post.
That post explained that the 'base to throat' distance was:
0. 5073" for the DD cone and the deflection test with their kit resulted in max deflection of 0. 415"
0. 5210" for the Stock cone and the deflection test with the stock is 0. 410".
So either the guide pin is starting out up from the bottom of the cone and travelling to the throat... . OR the guide pin is starting out at max bottom and not travelling right up to the throat of the cone. . Any thoughts on this??
In both your test procedures, neither one resulted in the guide pin making max travel based on the deflection(s) you demonstrated.
edit: Never mind, I think I figured out the discrepancy... it's the spacer washer. . ???
Is there something that is going wrong? Is this normal?
I think that utilizing "full" travel on the cone, with the guide pin is what we are aiming for, among other things. Yes/No ????
Am I on the right/wrong track here???
Bob.
Bob-
I think part of the confusion with the drawings I posted earlier is it shows the actual dimension of the cone but we don't get full use of this dimension due to the thickness of the guide pin. I think it is about 3mm (0. 118")
Another variable is the diaphragm itself. This is what makes the travel drop off so rapidly. Once it is expanded it moves very little.
What happens on the test fixture may not tell what is happening in the truck with 100% accuracy. I know if I take the nylon spacer out the fuel pin will strike the guide pin. Heat maybe the reason, I'm not sure but this is as close as I can get to real world measurements.
East Coast Jay-
During the process of measuring the springs I left the star wheel bottomed out when I put it back together one time. I hated it. Nothing but black smoke and a loss of acceleration. Turned the star wheel up 4 turns and all I get is a light haze and it pulls like crazy. I don't have enough air/ boost for the fuel it gives at that time on my setup.
WCJ
I think part of the confusion with the drawings I posted earlier is it shows the actual dimension of the cone but we don't get full use of this dimension due to the thickness of the guide pin. I think it is about 3mm (0. 118")
Another variable is the diaphragm itself. This is what makes the travel drop off so rapidly. Once it is expanded it moves very little.
What happens on the test fixture may not tell what is happening in the truck with 100% accuracy. I know if I take the nylon spacer out the fuel pin will strike the guide pin. Heat maybe the reason, I'm not sure but this is as close as I can get to real world measurements.
East Coast Jay-
During the process of measuring the springs I left the star wheel bottomed out when I put it back together one time. I hated it. Nothing but black smoke and a loss of acceleration. Turned the star wheel up 4 turns and all I get is a light haze and it pulls like crazy. I don't have enough air/ boost for the fuel it gives at that time on my setup.
WCJ
TTT,
Just didn't want this to get too far back in the page listing.
I think I asked this but..... for those of you who ordered and installed the DD AFC kit can you post your results up to now.
In particular I'm intersted in know if you all found excessive wear rates on your AFC cone. .
Also, how is the other aftermarket cone configuration coming along??
bob.
Just didn't want this to get too far back in the page listing.
I think I asked this but..... for those of you who ordered and installed the DD AFC kit can you post your results up to now.
In particular I'm intersted in know if you all found excessive wear rates on your AFC cone. .
Also, how is the other aftermarket cone configuration coming along??
bob.
"Also, how is the other aftermarket cone configuration coming along??"
#ad
#ad
It’s going great, Bob. I have been running this current design for a month now and am very happy with it. The face has three different radiuses, which gets progressively smaller toward the top. The initial guide pin depth is comparable to stock, while the top end allows for maximum effective guide pin travel (there can be too much). I have one small detail to fix, and I think it will be ready. There has been absolutely NO wear on any of my pins, they are very hard.
Mike
It’s going great, Bob. I have been running this current design for a month now and am very happy with it. The face has three different radiuses, which gets progressively smaller toward the top. The initial guide pin depth is comparable to stock, while the top end allows for maximum effective guide pin travel (there can be too much). I have one small detail to fix, and I think it will be ready. There has been absolutely NO wear on any of my pins, they are very hard.
Mike
Last edited by a moderator:
boatpuller
TDR MEMBER
Bob,
I purchased the DD pin but before I installed it I heard about the premature wear, My DD pin is very soft so I saw no reason to install it(it also doesn't make more power so why mess with it?)
I'm waiting for Old Smokeys Power Pin
Caleb
I purchased the DD pin but before I installed it I heard about the premature wear, My DD pin is very soft so I saw no reason to install it(it also doesn't make more power so why mess with it?)
I'm waiting for Old Smokeys Power Pin
Caleb
I'd really like to harden one and see if it could work a little better. You already have a modified cone to start with. Maybe it can have it's radius modified.
I really want to work up a VE. I don't want to go to a P-pump for 2 reasons..... $$$$$$$, and it wouldn't be a 1st Gen if you did... ..... sorry mark...
Hmmmm, were, in the pump head, can you shim to improve on fueling???
Can the KSB, be tweaked to alter timing and still be controllable and modestly reliable??
Is it possible to remotely alter your internal pump pressure and thereby alter your timing?? Kinda like a "box" does on the P pumps.
How about a "pot" that is throttle controlled, which in turn alters the full fuel setting?? Sound dumb?? Think about it and tell me if it is... .
As PW noted, at the 'start' position, the pump moves lots of fuel... can that condition be replicated during "running" condition??
If the pump can provide up to 8000 psi, is the plunger the only thing that can alter that pressure, particularly at lower RPM's?
What is the max effective "bar" rating on an injector that our pumps will handle??? 260 bar? 270 bar (3969psi)? more???
Bob.
I really want to work up a VE. I don't want to go to a P-pump for 2 reasons..... $$$$$$$, and it wouldn't be a 1st Gen if you did... ..... sorry mark...
Hmmmm, were, in the pump head, can you shim to improve on fueling???
Can the KSB, be tweaked to alter timing and still be controllable and modestly reliable??
Is it possible to remotely alter your internal pump pressure and thereby alter your timing?? Kinda like a "box" does on the P pumps.
How about a "pot" that is throttle controlled, which in turn alters the full fuel setting?? Sound dumb?? Think about it and tell me if it is... .
As PW noted, at the 'start' position, the pump moves lots of fuel... can that condition be replicated during "running" condition??
If the pump can provide up to 8000 psi, is the plunger the only thing that can alter that pressure, particularly at lower RPM's?
What is the max effective "bar" rating on an injector that our pumps will handle??? 260 bar? 270 bar (3969psi)? more???
Bob.
First, TTT... .
Second, I thought I'd add this info that Old Smoky researched out...
It relates to the diaphram, cone, guide pin travel...
"... . The trick was finding the maximum effective guide pin travel. Meaning enough to allow for max power increase, while not going too far. The guide pin lever can only push the guide pin in so far. BUT, I found that when the guide pin is all of the way (max fuel) the internal pump pressure can push the pin in farther if the AFC pin allows. The backside of the guide pin is shaped like a boat tail bullet, tapered toward the end. If it is allowed to be pushed in to far, where the taper starts, a small amount of fuel can pass by the seal and end up in the AFC housing. Only a few drops accumulated over a month or so, but this was definitely not desirable. That’s taken care of now. The magic number for the depth of the "notch" is aprox 0. 240 - 0. 245. I don't have the current models papers here.
Mike "... .
THANK YOU TO MIKE (OLD SMOKY)
This would come into play if the cone "notch" depth allows for excess travel beyond the beginning of the guide pin "tapper".
bob.
Second, I thought I'd add this info that Old Smoky researched out...
It relates to the diaphram, cone, guide pin travel...
"... . The trick was finding the maximum effective guide pin travel. Meaning enough to allow for max power increase, while not going too far. The guide pin lever can only push the guide pin in so far. BUT, I found that when the guide pin is all of the way (max fuel) the internal pump pressure can push the pin in farther if the AFC pin allows. The backside of the guide pin is shaped like a boat tail bullet, tapered toward the end. If it is allowed to be pushed in to far, where the taper starts, a small amount of fuel can pass by the seal and end up in the AFC housing. Only a few drops accumulated over a month or so, but this was definitely not desirable. That’s taken care of now. The magic number for the depth of the "notch" is aprox 0. 240 - 0. 245. I don't have the current models papers here.
Mike "... .
THANK YOU TO MIKE (OLD SMOKY)
This would come into play if the cone "notch" depth allows for excess travel beyond the beginning of the guide pin "tapper".
bob.
After spending some time with one of these pumps, they aren’t as complicated as I thought they where. However, I am not done learning yet. Ohhhhhh... I think I see the problem... . the last spring is upside down..... . .
I was looking at your graphs Jay, and it occurs to me that last bit of diaphram travel requires alot of boost to overcome the diaphram resistance. It's like the "spring rate" of the diaphram increases greatly.
Does anyone see the solution to that.....
... . I'm not trying to be a smart aleck here. . it seems there is something that can be done. I may have just found some "new/faster fuel"... either that or I took too much medication and it'll wear off later... which by the way is entirely possible...
Bob.
. . I was looking at your graphs Jay, and it occurs to me that last bit of diaphram travel requires alot of boost to overcome the diaphram resistance. It's like the "spring rate" of the diaphram increases greatly.
Does anyone see the solution to that.....
... . I'm not trying to be a smart aleck here. . it seems there is something that can be done. I may have just found some "new/faster fuel"... either that or I took too much medication and it'll wear off later... which by the way is entirely possible... Bob.
It looks to me like we also need to make a bellows type diaphram for the AFC pin to get effective travel. . Probably one with just a little more material in it to allow for the full travel after the . 35 ish area is hit.
I guess that would be the next step. How are you at cutting tire tubes? LOL...
J-eh
I guess that would be the next step. How are you at cutting tire tubes? LOL...
J-eh
:-laf 
You have mail...
Bob.
Bob.
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Renew
Subscribe
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Back Issues
Subscription Status
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