New Dyno, 14psi and 18psi (March)
03-21-2011, 04:37 PM
#1
New Dyno, 14psi and 18psi (March)
Went to the dyno, this time I did it with an UNLOCKED torque converter (which is why numbers come out low, that is NOT what the car really puts out, but at least we know the curve).
1st of all, dynojet's suck! went with 16psi from the street and at dyno it was 14psi since no load. you can see it on the graph, afr was also in the mid 10s (11's on street). I did another two runs, the 3rd was at about 18psi, still rich in the 10s, same exact curve, however almost same power output!!! as if there is something holding the engine back after certain boost.
After 5600RPM all curves ended up the same (so weird). Looks like there is a big restriction at 5440 rpm where it suddenly drops. Can this be a manifold issue? I know my timing was low as well but damn. There was also no knock either.
Also, on the street while getting passed that 5500rpm, the engine was more prone to knock (the J&S told me). Discuss....
1st of all, dynojet's suck! went with 16psi from the street and at dyno it was 14psi since no load. you can see it on the graph, afr was also in the mid 10s (11's on street). I did another two runs, the 3rd was at about 18psi, still rich in the 10s, same exact curve, however almost same power output!!! as if there is something holding the engine back after certain boost.
After 5600RPM all curves ended up the same (so weird). Looks like there is a big restriction at 5440 rpm where it suddenly drops. Can this be a manifold issue? I know my timing was low as well but damn. There was also no knock either.
Also, on the street while getting passed that 5500rpm, the engine was more prone to knock (the J&S told me). Discuss....
03-22-2011, 08:50 AM
#2
Dude I just recalled something from seeing your graph...
I too had that same drop off just before 5500. We noodled about this for a while, Fuel rail, MAF Voltage, piping, Manifold, turbine housing, etc... Many options were in the air at the time.
Def not an exhaust manifold issue, as I had the long-tube headers and you have the stockers. Def not MAF issue cus you dont even have a MAF and the same is going on. Not a fuel injector issue cus I had 440s and you have 555s. Surely not turbine housing, as yours is much bigger than the one on my old HX35.
Leaving us with only a few things in common as possible culprits; feed piping diameter, Intake Manifold, and fuel rail. (note that we only experience this after a certain level of WHP, so whatever it is... it's airflow-derived).
- Intake manifold can easily be tested by looking at the dynos from other boosted 3.5s with the FWD mani that are mid-300's whp+ range. Technically the same can be said about the fuel rail if they are using the same rail as us.
I think that after a certain level of airflow, the stock FWD IM just creates turbulence. Weather it's the plenum or the elbow. I would love to see what this looks like with the new custom IM that this guy made (forgot the name, this is recent tho). I would put my money on this as the factor... Also (sidenote) didnt Tilley's manage to mount the 00VI on a 3.5 LIM and proved that it made ubber power over the stock 3.5 IM? That's another thing you can look into to test out.
And so the hunt continues!
I too had that same drop off just before 5500. We noodled about this for a while, Fuel rail, MAF Voltage, piping, Manifold, turbine housing, etc... Many options were in the air at the time.
Def not an exhaust manifold issue, as I had the long-tube headers and you have the stockers. Def not MAF issue cus you dont even have a MAF and the same is going on. Not a fuel injector issue cus I had 440s and you have 555s. Surely not turbine housing, as yours is much bigger than the one on my old HX35.
Leaving us with only a few things in common as possible culprits; feed piping diameter, Intake Manifold, and fuel rail. (note that we only experience this after a certain level of WHP, so whatever it is... it's airflow-derived).
- Intake manifold can easily be tested by looking at the dynos from other boosted 3.5s with the FWD mani that are mid-300's whp+ range. Technically the same can be said about the fuel rail if they are using the same rail as us.
I think that after a certain level of airflow, the stock FWD IM just creates turbulence. Weather it's the plenum or the elbow. I would love to see what this looks like with the new custom IM that this guy made (forgot the name, this is recent tho). I would put my money on this as the factor... Also (sidenote) didnt Tilley's manage to mount the 00VI on a 3.5 LIM and proved that it made ubber power over the stock 3.5 IM? That's another thing you can look into to test out.
And so the hunt continues!
Last edited by 95BLKMAX; 03-22-2011 at 09:00 AM.
03-22-2011, 09:04 AM
#3
Damn eddy, thats an identical curve to mine, even the drop is EXACTLY the same. Hmmmm so its not stock headers.
This must be a FWD intake manifold issue, I have been trying to look for people with fwd and this kind of boost or HP but I dont think there are any lol. the few usually get custom manifolds. I have always been interested in the idea of the 00VI, but it will take a bit of work and still wont be perfect, I dont wanna go through all that. As for fuel rail, I think if it was a fuel rail issue it would show on the widebands as leaning out. (side note, they are 600cc sir lol).
For charge pipe diameter, that might be something else to consider, it is said that 500cfm is like the limit for 2", after that it just becomes a hot mess and inefficient, however what kind of HP would 500cfm be at? Edit: but wait, at only 9psi you still got that drop! its impossible for 2" piping to be a restriction on just 9psi, im ruling piping out.
Eddy, was this manifold on your dyno SSIM yet?
This must be a FWD intake manifold issue, I have been trying to look for people with fwd and this kind of boost or HP but I dont think there are any lol. the few usually get custom manifolds. I have always been interested in the idea of the 00VI, but it will take a bit of work and still wont be perfect, I dont wanna go through all that. As for fuel rail, I think if it was a fuel rail issue it would show on the widebands as leaning out. (side note, they are 600cc sir lol).
For charge pipe diameter, that might be something else to consider, it is said that 500cfm is like the limit for 2", after that it just becomes a hot mess and inefficient, however what kind of HP would 500cfm be at? Edit: but wait, at only 9psi you still got that drop! its impossible for 2" piping to be a restriction on just 9psi, im ruling piping out.
Eddy, was this manifold on your dyno SSIM yet?
Last edited by streetzlegend; 03-22-2011 at 09:12 AM.
03-22-2011, 09:24 AM
#6
Damn eddy, thats an identical curve to mine, even the drop is EXACTLY the same. Hmmmm so its not stock headers.
This must be a FWD intake manifold issue, I have been trying to look for people with fwd and this kind of boost or HP but I dont think there are any lol. the few usually get custom manifolds. I have always been interested in the idea of the 00VI, but it will take a bit of work and still wont be perfect, I dont wanna go through all that. As for fuel rail, I think if it was a fuel rail issue it would show on the widebands as leaning out. (side note, they are 600cc sir lol).
For charge pipe diameter, that might be something else to consider, it is said that 500cfm is like the limit for 2", after that it just becomes a hot mess and inefficient, however what kind of HP would 500cfm be at? Edit: but wait, at only 9psi you still got that drop! its impossible for 2" piping to be a restriction on just 9psi, im ruling piping out.
Eddy, was this manifold on your dyno SSIM yet?
This must be a FWD intake manifold issue, I have been trying to look for people with fwd and this kind of boost or HP but I dont think there are any lol. the few usually get custom manifolds. I have always been interested in the idea of the 00VI, but it will take a bit of work and still wont be perfect, I dont wanna go through all that. As for fuel rail, I think if it was a fuel rail issue it would show on the widebands as leaning out. (side note, they are 600cc sir lol).
For charge pipe diameter, that might be something else to consider, it is said that 500cfm is like the limit for 2", after that it just becomes a hot mess and inefficient, however what kind of HP would 500cfm be at? Edit: but wait, at only 9psi you still got that drop! its impossible for 2" piping to be a restriction on just 9psi, im ruling piping out.
Eddy, was this manifold on your dyno SSIM yet?
Yes sir, I did have SSIM by the time I went turbo.
03-22-2011, 09:32 AM
#8
00vi would be going backwards. Plenumn volume makes a big difference on bolt on 3.5's. (such as in sparks case with his custom IM) The 00vi has less overall plenumn volume than any stock 3.5 IM so you will do nothing but choke up the motor even more.
03-22-2011, 09:41 AM
#9
3.5 altima ser dyno'd 385@ 9 psi w meth and 2 extra injectors, stock timing, no drop off. also was auto. but it had a forward 2.5" feedpipe. ?????????? im sure if you go to twilight they can print the dyno for you if they or frank remember the name of the owner lol also was a dynojet. the guy used to work at wwr on an off the shelf gt35 .63 ar rear housing which is alot smaller than your hx40 ???
and isnt there a dyno of another turbo 3.5 tha put like 389 down??? did he also have this drop bc of the Intake Manifold? he had a forward feedpipe???
and isnt there a dyno of another turbo 3.5 tha put like 389 down??? did he also have this drop bc of the Intake Manifold? he had a forward feedpipe???
03-22-2011, 09:42 AM
#10
it does not have anything to do with the intake manifold, it's the cam timing
remember these other example's are of car's with varible cam or altered timing.
remember these other example's are of car's with varible cam or altered timing.
Last edited by t6378tp; 03-22-2011 at 09:47 AM.
03-22-2011, 09:44 AM
#11
HOWEVER, streetz makes a good point that to make it work would take time that he simply doesnt have, and it would still not be on point (given the mismatch of runners of UIM and LIM was the problem IIRC). So the Z33 IM option looks much more viable and beneficial than anything else ATM.
03-22-2011, 09:46 AM
#12
03-22-2011, 09:52 AM
#14
a bigger intake would be a temp fix and will alter the curve some but to really fix the problem well you'll need cams or different cam adapters
The cheapest, easiest and fastest thing would be a 350z intake, spacer and revup lim
The cheapest, easiest and fastest thing would be a 350z intake, spacer and revup lim
03-22-2011, 09:55 AM
#15
Agreed up to a point. It has already been proven that the 00VI holds power well passed the 3.5 FWD IM. Plenum volume isnt AS much of a factor with FI as it is with NA, since technically everything from the compressor to the intake valves is pressurized. The problem with the 3.5 FWD IM is turbulence, which the 00VI has considerably less, so I think it would hold power (even at that power level) much better than the 3.5 FWD IM.
HOWEVER, streetz makes a good point that to make it work would take time that he simply doesnt have, and it would still not be on point (given the mismatch of runners of UIM and LIM was the problem IIRC). So the Z33 IM option looks much more viable and beneficial than anything else ATM.
HOWEVER, streetz makes a good point that to make it work would take time that he simply doesnt have, and it would still not be on point (given the mismatch of runners of UIM and LIM was the problem IIRC). So the Z33 IM option looks much more viable and beneficial than anything else ATM.
03-22-2011, 10:11 AM
#16
03-22-2011, 02:19 PM
#20
Senior Member
Join Date: Jul 2009
Posts: 424
hey what you think about on below?:
http://forums.maxima.org/supercharge...5-4th-gen.html
this make over 420 whp?
http://forums.maxima.org/supercharge...5-4th-gen.html
this make over 420 whp?
03-25-2011, 01:10 PM
#21
Sorry for my segway post here, but I can't help but to wonder why turbo maxima's have such laggy power bands.
They look like 2L 4 cylinder dynos, but we are talking about 3.0L and 3.5L V6s here, so what gives? Are you guys using turbos that are way too big or what.
Dyno from my S4, which only has a tiny 2.7L V6.
FYI, the drop off after 6500 RPM is because of a issue I was having at the time of this dyno..(computer pulled out timing)
They look like 2L 4 cylinder dynos, but we are talking about 3.0L and 3.5L V6s here, so what gives? Are you guys using turbos that are way too big or what.
Dyno from my S4, which only has a tiny 2.7L V6.
FYI, the drop off after 6500 RPM is because of a issue I was having at the time of this dyno..(computer pulled out timing)
03-25-2011, 01:21 PM
#22
Sorry for my segway post here, but I can't help but to wonder why turbo maxima's have such laggy power bands.
They look like 2L 4 cylinder dynos, but we are talking about 3.0L and 3.5L V6s here, so what gives? Are you guys using turbos that are way too big or what.
Dyno from my S4, which only has a tiny 2.7L V6.
FYI, the drop off after 6500 RPM is because of a issue I was having at the time of this dyno..(computer pulled out timing)
They look like 2L 4 cylinder dynos, but we are talking about 3.0L and 3.5L V6s here, so what gives? Are you guys using turbos that are way too big or what.
Dyno from my S4, which only has a tiny 2.7L V6.
FYI, the drop off after 6500 RPM is because of a issue I was having at the time of this dyno..(computer pulled out timing)
i think youre comparing apples to oranges, the above dyno is of a supercharged 3.5, and streetz has a large turbo. this car still had a bit too large turbo but powerband is much better on a 3.0 @ 10 psi..sorry cant find one w rpm vs speed but you see the difference
03-28-2011, 01:21 PM
#24
The image below is from my stock compression setup with the same boost setup. Notice the much beefier low end torque. The lower line in the chart is my NA pre-boost setup on a stock VQ35 with Z33 IM.
04-02-2011, 05:52 AM
#26
This caught my eye, cause the point where you're having your issues is the exact same point at which my car has some detonation/knocking issues:
My graph doesn't show as much of a drop as yours (due to a lack of a J&S to pull timing in my case), but it is definitely right in the same RPM ballpark.
My graph doesn't show as much of a drop as yours (due to a lack of a J&S to pull timing in my case), but it is definitely right in the same RPM ballpark.
04-02-2011, 08:41 AM
#29
04-02-2011, 08:46 AM
#30
the dip in his case can be related to the knock no? disturbing power? not sure i buy the IM theory.. maybe the cam timing, i still think you should slap a properly dont ssim on there and redyno , lock the tc this time. make sure the j&S isnt picking up false knock
04-02-2011, 09:07 AM
#32
Ed's dip is identical almost a replica to mine, however mine was not caused by detonation, so I dont think his detonation was what caused that dip but were due to seperate issues (too much timing so it knocked, and cam/manifold choke). I have no doubt its an intake or cam issue.
04-02-2011, 03:07 PM
#33
After 5600RPM all curves ended up the same (so weird). Looks like there is a big restriction at 5440 rpm where it suddenly drops. Can this be a manifold issue? I know my timing was low as well but damn. There was also no knock either.
Also, on the street while getting passed that 5500rpm, the engine was more prone to knock (the J&S told me). Discuss....
Also, on the street while getting passed that 5500rpm, the engine was more prone to knock (the J&S told me). Discuss....
Copy/paste from (good read btw): Fluid Dynamics: Real Fluids
Eventually they are no longer able to hold the flow in layers and the fluid starts to rotate.
This causes the fluid motion to rapidly becomes turbulent. Fluid from the fast moving region moves to the slower zone transferring momentum and thus maintaining the fluid by the wall in motion. Conversely, slow moving fluid moves to the faster moving region slowing it down. The net effect is an increase in momentum in the boundary layer. We call the part of the boundary layer the turbulent boundary layer.
This causes the fluid motion to rapidly becomes turbulent. Fluid from the fast moving region moves to the slower zone transferring momentum and thus maintaining the fluid by the wall in motion. Conversely, slow moving fluid moves to the faster moving region slowing it down. The net effect is an increase in momentum in the boundary layer. We call the part of the boundary layer the turbulent boundary layer.
At the edge of the separated boundary layer, where the velocities change direction, a line of vortices occur (known as a vortex sheet). This happens because fluid to either side is moving in the opposite direction.
This boundary layer separation and increase in the turbulence because of the vortices results in very large energy losses in the flow.
These separating / divergent flows are inherently unstable and far more energy is lost than in parallel or convergent flow.
This boundary layer separation and increase in the turbulence because of the vortices results in very large energy losses in the flow.
These separating / divergent flows are inherently unstable and far more energy is lost than in parallel or convergent flow.
TLDR: I think it's a manifold issue...
04-02-2011, 06:58 PM
#34
http://forums.maxima.org/forced-indu...ok-inside.html
thats w a maxima intake, give me time, and youll see my dyno w 6-8 psi and meth (: sure it will look like ed's without knock and will not have that drop off till pob 6k
thats w a maxima intake, give me time, and youll see my dyno w 6-8 psi and meth (: sure it will look like ed's without knock and will not have that drop off till pob 6k
04-02-2011, 10:33 PM
#35
http://forums.maxima.org/forced-indu...ok-inside.html
thats w a maxima intake, give me time, and youll see my dyno w 6-8 psi and meth (: sure it will look like ed's without knock and will not have that drop off till pob 6k
thats w a maxima intake, give me time, and youll see my dyno w 6-8 psi and meth (: sure it will look like ed's without knock and will not have that drop off till pob 6k
Also, if you'll notice there is an obvious drop in power just after 5300rpm (torque/hp x-over). While not hugely noticeable, it is there. I think it's less noticeable because of more dynamic timing control.
04-02-2011, 10:36 PM
#36
Well, as i'm sure you're aware, that dyno was done on a full 3.5 (as in full timing with VTC's). I think it's a case of apples and oranges considering most 3.5 swapped 4th gens lack any dynamic control of timing or multiple plots of different timing scaling...
Also, if you'll notice there is an obvious drop in power just after 5300rpm (torque/hp x-over). While not hugely noticeable, it is there. I think it's less noticeable because of more dynamic timing control.
Also, if you'll notice there is an obvious drop in power just after 5300rpm (torque/hp x-over). While not hugely noticeable, it is there. I think it's less noticeable because of more dynamic timing control.
