Dyno results: Stillen Headers
10-14-2003, 07:17 PM
#1
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Dyno results: Stillen Headers
THIS POST IS NOT FLAMING STILLEN OR SAYING THIS PRODUCT IS WORTHLESS!!!!!!!!!!!!!!!! my car might have a few issues.
dyno before the headers (1yr ago) = 228hp 236tq
for everyone that has been waiting i finally got my car dynod today. 1st run a whoping 221hp 22Xtq...... 2nd and 3rd runs were about the same. IM NOT HAPPY AT ALL. i reset my ECU while the car is still strapped down. to my suprise i hit 228hp 228tq..... i look at my chart and i notice a MASSIVE LOSS from 4300-5300.... almost 30hp..... also the rpm thing kept losing signal at 4k rpms which is the same time i lose hp...... if anyone knows the prob let me know. im baffled at this point. i get on the phone and give stillen a phone call as soon as my car gets off the dyno. talked to the normal guy i deal with and tell him in a very calm but firm way that i was ****ING MAD..... i dont pau over a grand to lose 8tq. they asked me to fax them the dyno and said that from thier dyno they peaked (memory) 19hp @ 5800rpms & 17tq @ 5700rpms. i told them i wanted a actual photo of it. he said he will work on it. so stillen is in the process of reviewing my dyno. im in the process of pullin my hair out trying to find out what the problem is. someone with more knowledge than me please help!
TOTAL GAINS= 0hp -8tq (yes thats a negative)
will
dyno before the headers (1yr ago) = 228hp 236tq
for everyone that has been waiting i finally got my car dynod today. 1st run a whoping 221hp 22Xtq...... 2nd and 3rd runs were about the same. IM NOT HAPPY AT ALL. i reset my ECU while the car is still strapped down. to my suprise i hit 228hp 228tq..... i look at my chart and i notice a MASSIVE LOSS from 4300-5300.... almost 30hp..... also the rpm thing kept losing signal at 4k rpms which is the same time i lose hp...... if anyone knows the prob let me know. im baffled at this point. i get on the phone and give stillen a phone call as soon as my car gets off the dyno. talked to the normal guy i deal with and tell him in a very calm but firm way that i was ****ING MAD..... i dont pau over a grand to lose 8tq. they asked me to fax them the dyno and said that from thier dyno they peaked (memory) 19hp @ 5800rpms & 17tq @ 5700rpms. i told them i wanted a actual photo of it. he said he will work on it. so stillen is in the process of reviewing my dyno. im in the process of pullin my hair out trying to find out what the problem is. someone with more knowledge than me please help!
TOTAL GAINS= 0hp -8tq (yes thats a negative)
will
10-14-2003, 07:31 PM
#6
Well that makes both Studman & youself losing power with the Stillen Headers. This isnt looking too good. This isnt making any sense...when the 3.5 auto altima dyno'd with the prototype hotshot headers, it put down well over 20whp gain same with the torque. It ran pretty damn lean too, with an FMU it would have put down a guesstimated 30+whp IMO. We all know the injectors on the 3.5 get maxxed out pretty quick.
How does your A/F ratios look?
What im thinking is happening is the ECU is picking up that the engine is not getting an adequate fuel supply and is closing the Throttle body plate (it is drive be way after all) to compensate and keep the A/F ratios to the point were you won't fry the piston. I "think" thats why your seeing a loss that large when you should be getting a gain about that large IMO. I think the injectors are the problem...if im wrong some1 please correct me but this is what im placing my bet on.
How does your A/F ratios look?
What im thinking is happening is the ECU is picking up that the engine is not getting an adequate fuel supply and is closing the Throttle body plate (it is drive be way after all) to compensate and keep the A/F ratios to the point were you won't fry the piston. I "think" thats why your seeing a loss that large when you should be getting a gain about that large IMO. I think the injectors are the problem...if im wrong some1 please correct me but this is what im placing my bet on.
10-14-2003, 07:36 PM
#7
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i think its fuel delivery. didnt get A/F (they said it would take too long). im gettin a AFC soon. dyno tune comes after.
will
will
10-14-2003, 07:58 PM
#11
Good lord...I have so many thoughts running through my head right now...let me try and jot some of them down, and I'll come back and edit as needed...
It does make sense that the ECU would tune out air (by closing the TB plate) in an attempt to keep the air/fuel ratio favorable for longevity (it's ability to flow air is greater at this point than it's ability to provide fuel). That's what the stock ECU is all about...getting from point A to B for as long as reliably possible. Adding headers (as I guessed) will cause you to run lean (almost all major exhaust changes will cause this, but it's never as drastic as when the stock exhaust manifolds are removed/replaced with headers). IF the stock VQ35 injectors are maxed out at this point, then, at least in my mind, everything is happening as it should.
The car needs to be driven over 200-300 miles so it can fully (or as fully as it has fuel for) "adapt" to the change. It can't possible adapt as quickly as one dyno session...or even overnight. I say drive the sucker as much as possible over the next week, then dyno again. Tune after putting the 2-300 miles on the car...
This is just my opinion, and it's based on things that have happened to vehicles I have owned or currently own now (after adding significant exhaust mods; without changing fuel delivery)...
It does make sense that the ECU would tune out air (by closing the TB plate) in an attempt to keep the air/fuel ratio favorable for longevity (it's ability to flow air is greater at this point than it's ability to provide fuel). That's what the stock ECU is all about...getting from point A to B for as long as reliably possible. Adding headers (as I guessed) will cause you to run lean (almost all major exhaust changes will cause this, but it's never as drastic as when the stock exhaust manifolds are removed/replaced with headers). IF the stock VQ35 injectors are maxed out at this point, then, at least in my mind, everything is happening as it should.
The car needs to be driven over 200-300 miles so it can fully (or as fully as it has fuel for) "adapt" to the change. It can't possible adapt as quickly as one dyno session...or even overnight. I say drive the sucker as much as possible over the next week, then dyno again. Tune after putting the 2-300 miles on the car...
This is just my opinion, and it's based on things that have happened to vehicles I have owned or currently own now (after adding significant exhaust mods; without changing fuel delivery)...
10-14-2003, 08:20 PM
#13
to me, i dont see why anyone without forced induction would get headers. with a y pipe and a cat back exhaust, you are really releasing ALOT of backpressure in the exhaust. probably just borderline good for performance on naturally asperated cars. if you then change out the headers, it seems to me that you are taking out way too much. in order for an engine to run its best, it must have backpressure. now if you have a supercharger or a turbo, then these headers would probably help immensly. has anyone with FI dyno'ed these headers?
just my $.02
just my $.02
10-14-2003, 08:22 PM
#14
Originally Posted by WILLSE
i think its fuel delivery. didnt get A/F (they said it would take too long). im gettin a AFC soon. dyno tune comes after.
will
will
the ratios down. I know for a fact that alti ran pretty damn lean and the injectors were pretty much maxxed out. Studman has a Greddy E-manage if I recall correctly and I dont think his problem is solved. I belive the SAFC is said to give you an adjustable 50-150% of the OEM settings. Im just thinking if the injectors are already pretty much topped off, from were could it push in more fuel.
Im just looking at it this way, the Hotshot unit was basically put together on the alti as the installer was going...peice by peice. So it wasnt exactly a "perfect" set of headers. Im sure he wasnt able to work out every little bend, and im sure there was quite a few rough spot and areas were the welds and bends interfered with the flow of the exhaust.
So there wasnt much R&D time for it, just however long it too to rig it up so to speak. The power gain was still in the 24-26whp range and this was on the auto and while running quite a bit lean.
What im thinking is since stillen hade more then enough time to R&D these headers and work out basically all fitment issues and anything else that would possible interfere with the exhaust flow, it pushed the already lean injectors even futher causing the ECU to interfere and pull back in order to keep the 3.5 from running dangerously lean and frying a piston. Header equipped cars do have the tendance to run a bit lean, and in some cases burn a piston.
Dave/subdocmax, im pretty sure you could have Dave M, comment on this since he was the one who dyno's that car?
I still place my bet on the Fuel system, I wouldnt blame stillen as of yet but I think this is were the problem is at right now.
10-14-2003, 08:38 PM
#17
Originally Posted by mad2kmax
to me, i dont see why anyone without forced induction would get headers. with a y pipe and a cat back exhaust, you are really releasing ALOT of backpressure in the exhaust. probably just borderline good for performance on naturally asperated cars. if you then change out the headers, it seems to me that you are taking out way too much. in order for an engine to run its best, it must have backpressure. now if you have a supercharger or a turbo, then these headers would probably help immensly. has anyone with FI dyno'ed these headers?
just my $.02
just my $.02
And before you make a non-justified comment on backpressure, go do some more research on the dynamics of the flow of exhaust gases and how they truly effect the operation and performance of an engine. An engine does not "need" any certain amount of backpressure to successfully operate at a given RPM...it's a myth. A certain amount of backpressure will ALWAYS be in any given exhaust system (that is, in any vehicle with ODBII systems installed). Unless you are running totally open headers vented straight to atmosphere, you'll have all the backpressure you'll need.
10-14-2003, 08:44 PM
#19
The only time you'll every have in issue is if the piping is too wide. You wont the exhaust to flow out, not just get spat out of the heads and just hang around in the pipes waiting to get pushed out. It kinda acts like a syphon and keeps pulling once the flow gets started. If the piping is too wide however, it could become an issue.
10-14-2003, 08:50 PM
#20
Originally Posted by HitManSE
The only time you'll every have in issue is if the piping is too wide. You wont the exhaust to flow out, not just get spat out of the heads and just hang around in the pipes waiting to get pushed out. It kinda acts like a syphon and keeps pulling once the flow gets started. If the piping is too wide however, it could become an issue.
Are you referring to the exhaust pulses, velocity, fluid temperature and pressure levels ?? Or something else ??
10-14-2003, 08:56 PM
#21
Wow Dave, your finally not a newbie anymore 
anyway...the guy that owns (or should I say owned) the alti was Sean, his SN over on altimas.net is Snolden and ive actually PM'd him a few times a while back regarding the headers.
His car was putting out 232 whp is what he said, the gains were about 20whp (give or take a few
)
Actually...here is his dyno graph, both with the headers
Check out the area were the power dips, its not an rpm based dyno and looks all screw due to the fact its an auto but its still #'s non the less.
His exact comments about the headers were...
"OMFG! Prototype hot shot headers. look like crap but a 21whp increase"
so I guess its a 21whp increase.
Edit: Quicksilver-I know you know what your doing, I was trying to explain to whomever didnt know. My mistake for quoting it to your post..will fix in a sec.
Btw-Just for the record that alit had a WAI, Stillen exhaust and a UDP.
anyway...the guy that owns (or should I say owned) the alti was Sean, his SN over on altimas.net is Snolden and ive actually PM'd him a few times a while back regarding the headers. His car was putting out 232 whp is what he said, the gains were about 20whp (give or take a few
)Actually...here is his dyno graph, both with the headers
Check out the area were the power dips, its not an rpm based dyno and looks all screw due to the fact its an auto but its still #'s non the less.
His exact comments about the headers were...
"OMFG! Prototype hot shot headers. look like crap but a 21whp increase"
so I guess its a 21whp increase.
Edit: Quicksilver-I know you know what your doing, I was trying to explain to whomever didnt know. My mistake for quoting it to your post..will fix in a sec.
Btw-Just for the record that alit had a WAI, Stillen exhaust and a UDP.
10-14-2003, 08:57 PM
#22
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WTF!! How in the hell is this happening. I'm getting a little worried now that maybe I shouldn't have ordered these headers. Though it's a little too late now. One thought I've got is that isn't possible that because both Willse and Studman both have highflow cats and b-pipes that maybe their cars won't really benefit that much from headers? I'm mean how would somebody like me probably fair with having these headers? My mods are Injen CAI, Stillen exhaust and Unorthodox udp. Please give your opinions on these questions. Thanks.
10-14-2003, 09:03 PM
#23
Originally Posted by 1BADMAX
WTF!! How in the hell is this happening. I'm getting a little worried now that maybe I shouldn't have ordered these headers. Though it's a little too late now. One thought I've got is that isn't possible that because both Willse and Studman both have highflow cats and b-pipes that maybe their cars won't really benefit that much from headers? I'm mean how would somebody like me probably fair with having these headers? My mods are Injen CAI, Stillen exhaust and Unorthodox udp. Please give your opinions on these questions. Thanks.
If they are designed correctly, they "should" provide positive gains...
If they were tested correctly, they "should" have at least come up with the same problem that we are currently seeing right now...
If they (and they being Stillen) have already had this happen to their test cars, then they "should" know how to resolve it, or they "should" say that it is just part of the natural ECU learning process...
10-14-2003, 09:14 PM
#24
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Does the vq35 have a knock sensor?? i know with the qr25 the knock sensor is over-sensitive and in some cases will pull timing and actually loose power
10-14-2003, 09:17 PM
#25
Originally Posted by houstonspecv
Does the vq35 have a knock sensor?? i know with the qr25 the knock sensor is over-sensitive and in some cases will pull timing and actually loose power
10-14-2003, 09:23 PM
#27
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Originally Posted by HitManSE
Yes it does, but a loss that large? I doubth timing will be pulled THAT much.
10-14-2003, 09:28 PM
#28
Originally Posted by houstonspecv
unfortunately yes it does. i forget which magazine, i think it was nissan performance magazine that dynoed an altima 3.5se and it lost like 20whp between runs
Once again pointing the finger at the fuel supply not being adequate enough.
10-14-2003, 09:31 PM
#29
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Originally Posted by HitManSE
Well, that one more thing too look at BUT it wouldnt pull timing unless it felt knock/ping/detenation (whatever you want to call it) which is cause by lean A/F ratios Once again pointing the finger at the fuel supply not beind adequate enough.
Once again pointing the finger at the fuel supply not beind adequate enough.actually it would if it work that way if it wasnt over-sensitive, but it is and it detects valvetrain noise and other noise and believes its detonation and retards timing.
the knock sensor is only supposed to be put on at 13ft-lbs and on my car is was put on at about 115ft-lbs. So i took it off and retorqued it to 13.
When i installed my AEBS header i datalogged my car and it wasnt retarding timing at all, so hopefully that fixed it
10-14-2003, 09:52 PM
#30
Wow that just sucks. It would have been alot bette to get the wideband o2 sensor option. I would have shown if the a/f was getting rich/lean etc..
Unless Nissan had calibrated their injectors to function close to 80% duty on the stock hp ratings, I just don't see them going lean or overdriven. Maybe there's something in the ecu program that prevents big changes in the a/f ratios. But aren't the 3.5vqs in the Zs doing just fine w/ the sc and turbos?
Maybe there's something seriously wrong with the resonance tuning of the headers that make it drop at those rpm.
Anyway, how about hooking up one of those OBD-II data loggers and look the the injector duty cycles and maybe the o2 sensor functions??
Also a fautly KS usually shows a real choppy line? Not just one huge dip?
Losing the rpm signal at 4k is also very odd. Might point to an ecu problem or a crank angle sensor problem?
Unless Nissan had calibrated their injectors to function close to 80% duty on the stock hp ratings, I just don't see them going lean or overdriven. Maybe there's something in the ecu program that prevents big changes in the a/f ratios. But aren't the 3.5vqs in the Zs doing just fine w/ the sc and turbos?
Maybe there's something seriously wrong with the resonance tuning of the headers that make it drop at those rpm.
Anyway, how about hooking up one of those OBD-II data loggers and look the the injector duty cycles and maybe the o2 sensor functions??
Also a fautly KS usually shows a real choppy line? Not just one huge dip?
Losing the rpm signal at 4k is also very odd. Might point to an ecu problem or a crank angle sensor problem?
10-14-2003, 11:08 PM
#31
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Originally Posted by Jeff92se
Losing the rpm signal at 4k is also very odd. Might point to an ecu problem or a crank angle sensor problem?
i dunno. this car is really wierd. i dunno where to start. im tired of thinking for the night. thanks for your help guys!
will
10-14-2003, 11:56 PM
#32
almost $1000 and 0 hp and -8 tq... that is really really fuc*ing terrible...
I dont know but how about we have to change the ECU, maybe headers works good with it... I have no idea guys!! return it back... before headers came out Stillen said "more power and
" I heard from Stillen that the headers will give us more than 20hp... this is A BIG BUL***T... 
this guys gave almost $1000 for nothing... MY GOD im very mad guys... just try to get your money back!! 
I dont know but how about we have to change the ECU, maybe headers works good with it... I have no idea guys!! return it back... before headers came out Stillen said "more power and
" I heard from Stillen that the headers will give us more than 20hp... this is A BIG BUL***T... this guys gave almost $1000 for nothing... MY GOD im very mad guys... just try to get your money back!!
10-15-2003, 12:29 AM
#33
although I doubt it is the problem, If you would like to rule out the knock sensor possiably retarding the timing/etc, simply use a resistor ( between 500k and 620k ohms) in place of the knock sensor.
10-15-2003, 05:24 AM
#34
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Originally Posted by MrGone
although I doubt it is the problem, If you would like to rule out the knock sensor possiably retarding the timing/etc, simply use a resistor ( between 500k and 620k ohms) in place of the knock sensor.
10-15-2003, 06:28 AM
#35
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Will's TQ is where the big loss is. Right as he's hitting 44xx it nose dives from 226ish and falls to 176ish at 48xx. Then it starts climbing again. This was repeatable on 6 runs, the dip starts right at 44xx.
Will had the headers on for over a week before this dyno, the car also has 20k more miles on it than studmans, I wonder how his plugs & injectors look.
Also how would the numbers look with a GAB.
My car ran 212.xxHP 231.xxTQ.
Will had the headers on for over a week before this dyno, the car also has 20k more miles on it than studmans, I wonder how his plugs & injectors look.
Also how would the numbers look with a GAB.
My car ran 212.xxHP 231.xxTQ.
10-15-2003, 07:23 AM
#36
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WILLSE Your header problems....
can be solved if you dyno tune . From what it seems like, you have worked on the air flow of things w/headers,intake ,exhaust, but no real work on fuel and other internals. An upgrade ECU would help too....remeber your stock ECU is still reading a stock set up. Wether or not you reset it or not, you have to have an ECU that is programmed to your mods.If it was that easy to just reset the ECU w/ mods, there would be no reason for performance companies to sell perfromace ECU's.
They would be out of business......
I am not surprised that you gained nothing in Hp or torque, actually you are rather lucky that you didn't actually lose HP/Trq.
My suggestion to you is to , is to keep the headers and get an Upgraded ECU as soon as possible. Your headers are just the next stepping stone in the process of attaining speed. Now you need something to manage your air to fuel ratio to fully get the use of your headers,intake , and exhaust.
Bigger injectors are not neccessary for your setup. If you were going with a turbo /supercharger setup , then definitely get the bigger injectors to cram as much fuel as possible. Or if you decided to build a monster Vq, with bigger pistons, springs , cams,crank, etc. then yes bigger injectors would be a go with that setup.
For right now you are just running a simple street setup that doesn't require bigger injectors. Remeber too, that bigger isn't always better, the guy who has a setup where everything is working together in harmony will win more races than somebody who just slaps on parts because some company "says" that it will give them XXX amount of HP.
One thing to remember is that when companies start bragging that they can give XXX amount of Hp with there product, ask yourself this? Are they using the vehicle that you drive to get that HP? Is the car there using stock or modified to get those quoted numbers that they say it will give you? Simple questions like that will save you time and your hard earned money on "gimmick " products that don't work for your vehicle, even if it is coming from a reputable company.
One thing i learned , especially when i had my 94 twin turbo Z was not to just buy anything , or slap anything on my ride because of what some company was bragging what there product could do. If they never touched or dynoed that part on my Z , why the hell would i want to buy it? I do alot of research before i just slap a mod on my car. I advise you do the same......
Stillin is a so-so company, i like there areo kits/dress up stuff, etc but there performance upgrades are questionable.
For your ECU upgrade i highly recomend Jim wolf technoligies. Many of the Z community has nothing but praise to say about there ECU, Stillin ECU,s were not even close to quality and perfromance, many have had problems with Stillin ECU's and are not satisfied with there purchase.
I think Jim wolf makes ECU's for our Max's too, check, or i can check for you...
Well sorry for your dissapointing results, don't give up hope because and upgraded Ecu and a good dyno tune can get you rolling again to satisfaction.
They would be out of business......
I am not surprised that you gained nothing in Hp or torque, actually you are rather lucky that you didn't actually lose HP/Trq.
My suggestion to you is to , is to keep the headers and get an Upgraded ECU as soon as possible. Your headers are just the next stepping stone in the process of attaining speed. Now you need something to manage your air to fuel ratio to fully get the use of your headers,intake , and exhaust.
Bigger injectors are not neccessary for your setup. If you were going with a turbo /supercharger setup , then definitely get the bigger injectors to cram as much fuel as possible. Or if you decided to build a monster Vq, with bigger pistons, springs , cams,crank, etc. then yes bigger injectors would be a go with that setup.
For right now you are just running a simple street setup that doesn't require bigger injectors. Remeber too, that bigger isn't always better, the guy who has a setup where everything is working together in harmony will win more races than somebody who just slaps on parts because some company "says" that it will give them XXX amount of HP.
One thing to remember is that when companies start bragging that they can give XXX amount of Hp with there product, ask yourself this? Are they using the vehicle that you drive to get that HP? Is the car there using stock or modified to get those quoted numbers that they say it will give you? Simple questions like that will save you time and your hard earned money on "gimmick " products that don't work for your vehicle, even if it is coming from a reputable company.
One thing i learned , especially when i had my 94 twin turbo Z was not to just buy anything , or slap anything on my ride because of what some company was bragging what there product could do. If they never touched or dynoed that part on my Z , why the hell would i want to buy it? I do alot of research before i just slap a mod on my car. I advise you do the same......
Stillin is a so-so company, i like there areo kits/dress up stuff, etc but there performance upgrades are questionable.
For your ECU upgrade i highly recomend Jim wolf technoligies. Many of the Z community has nothing but praise to say about there ECU, Stillin ECU,s were not even close to quality and perfromance, many have had problems with Stillin ECU's and are not satisfied with there purchase.
I think Jim wolf makes ECU's for our Max's too, check, or i can check for you...
Well sorry for your dissapointing results, don't give up hope because and upgraded Ecu and a good dyno tune can get you rolling again to satisfaction.
10-15-2003, 07:25 AM
#37
Jim Wolf does not make ECU's for our 3.5L's, at least none that I am aware of. The only one out there doing anything is Technosquare...
And you need to do a little more homework before saying that stock injectors would be fine for "street use"...there are plenty of applications that require larger injectors before even going to any kind of boost.
And you need to do a little more homework before saying that stock injectors would be fine for "street use"...there are plenty of applications that require larger injectors before even going to any kind of boost.
10-15-2003, 07:42 AM
#38
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Originally Posted by Quicksilver
Jim Wolf does not make ECU's for our 3.5L's, at least none that I am aware of. The only one out there doing anything is Technosquare...
And you need to do a little more homework before saying that stock injectors would be fine for "street use"...there are plenty of applications that require larger injectors before even going to any kind of boost.
And you need to do a little more homework before saying that stock injectors would be fine for "street use"...there are plenty of applications that require larger injectors before even going to any kind of boost.
True....but for his setup larger injectors are not needed.Unless he wants to waste his money on more gas at the pump.
10-15-2003, 07:50 AM
#40
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Originally Posted by Rafe
True....but for his setup larger injectors are not needed.Unless he wants to waste his money on more gas at the pump.
Actually i take what i said back, since he has pretty much worked on the air flow setup w/ I/H/ E, then yes bigger injectors would work. More air needs more fuel...
Good call