HKS Setup
Banned
Joined: Mar 2004
Posts: 1,289
Likes: 0
From: Australia
Originally posted by Z1 Performance
Given that these injectors are driven by their own MAP sensor and are sized pretty decently, I am fairly sure the fuel flow would be more than adequate to each cylinder. Much easier to do this in a V engine than in an I engine
Given that these injectors are driven by their own MAP sensor and are sized pretty decently, I am fairly sure the fuel flow would be more than adequate to each cylinder. Much easier to do this in a V engine than in an I engine
Some cylinders could be overly rich whilst other cylinders could be very lean (this can cause detonation and elevated exhaust gas temperatures on the lean cylinders)................not an ideal approach on FI engines.................6 larger fuel injectors which replace the 6 stock Nissan fuel injectors is the best and safest method for all high performance FI engines.
If I were to install an HKS supercharger system to a Z engine I would definitely recommend replacing the 2 aux injectors supplied in the HKS supercharger system with 6 larger injectors which mount in the factory nissan plenum position.
Better to be safe than sorry.
Peter
APS
Originally posted by APS
I'm not at all concerned with the load reference (map sensor) utilised to control the 2 additional fuel injectors or even the fuel flow (size of the 2 additional injectors)................what concerns me is that this approach cannot provide perfect fuel delivery to all 6 cylinders equally.
Some cylinders could be overly rich whilst other cylinders could be very lean (this can cause detonation and elevated exhaust gas temperatures on the lean cylinders)................not an ideal approach on FI engines.................6 larger fuel injectors which replace the 6 stock Nissan fuel injectors is the best and safest method for all high performance FI engines.
If I were to install an HKS supercharger system to a Z engine I would definitely recommend replacing the 2 aux injectors supplied in the HKS supercharger system with 6 larger injectors which mount in the factory nissan plenum position.
Better to be safe than sorry.
Peter
APS
I'm not at all concerned with the load reference (map sensor) utilised to control the 2 additional fuel injectors or even the fuel flow (size of the 2 additional injectors)................what concerns me is that this approach cannot provide perfect fuel delivery to all 6 cylinders equally.
Some cylinders could be overly rich whilst other cylinders could be very lean (this can cause detonation and elevated exhaust gas temperatures on the lean cylinders)................not an ideal approach on FI engines.................6 larger fuel injectors which replace the 6 stock Nissan fuel injectors is the best and safest method for all high performance FI engines.
If I were to install an HKS supercharger system to a Z engine I would definitely recommend replacing the 2 aux injectors supplied in the HKS supercharger system with 6 larger injectors which mount in the factory nissan plenum position.
Better to be safe than sorry.
Peter
APS
I do think this is one of the better kits but why only (2) injectors? It makes sense to replace all six of them but then again they did test this out and its going to be carb legal if its not already so perhaps they needed to make some compromises for reliablity sake and emissions not to mention this being a kit just to use with NO additional mods. Perhaps on a fully stock car the 2 injectors pose little problems and give the car the look of it belongs like that straight from the factory.
Banned
Joined: Mar 2004
Posts: 1,289
Likes: 0
From: Australia
Originally posted by QikTimez
Peter,
APS offers training and support to a "registered" network of installers? How do I go about finding a "registered" installer ?
Peter,
APS offers training and support to a "registered" network of installers? How do I go about finding a "registered" installer ?
Your also welcome to pm me if you want more specific dealer information.
Thanks
Peter
Decisions
Love these posts. I have a 2004 track and am going with FI, have not decided which SC or TT but have dropped the money for a new block and forged internals, stud kit , etc. What kind of training do reps receive for installing these systems . I do like the well thought out APS system. But since they are new, how well are the intallers trained or is my car going to be a test bed?
Anyone, thanks Ken
Anyone, thanks Ken
Registered User
Joined: Feb 2003
Posts: 154
Likes: 0
From: Doha, Qatar
Originally posted by APS
We all know that power in the 350Z is highly addictive - no matter where in the RPM range power is produced. Let’s face it, when an enthusiast has the ability to up the boost, he generally does at some point or another. There’s an old motto that goes something like this - Crank up the boost until something breaks and then turn it back half a psi.
Happy and responsible boosting to all - it's all about the fun factor!
Peter
We all know that power in the 350Z is highly addictive - no matter where in the RPM range power is produced. Let’s face it, when an enthusiast has the ability to up the boost, he generally does at some point or another. There’s an old motto that goes something like this - Crank up the boost until something breaks and then turn it back half a psi.
Happy and responsible boosting to all - it's all about the fun factor!
Peter
Registered User
Joined: Mar 2004
Posts: 1,144
Likes: 1
From: West Springfield, MA
Here's what I kow on the fueling issue.....
Originally posted by 350z4steve
I do think this is one of the better kits but why only (2) injectors? It makes sense to replace all six of them but then again they did test this out and its going to be carb legal if its not already so perhaps they needed to make some compromises for reliablity sake and emissions not to mention this being a kit just to use with NO additional mods. Perhaps on a fully stock car the 2 injectors pose little problems and give the car the look of it belongs like that straight from the factory.
I do think this is one of the better kits but why only (2) injectors? It makes sense to replace all six of them but then again they did test this out and its going to be carb legal if its not already so perhaps they needed to make some compromises for reliablity sake and emissions not to mention this being a kit just to use with NO additional mods. Perhaps on a fully stock car the 2 injectors pose little problems and give the car the look of it belongs like that straight from the factory.
In all engines, stock or not, the A/F ratio is not identical from cylinder to cylinder. That means some cylinders are leaner than others. In the case of the Z, the rear two cylinders (5&6) are leaner due to the plenum configuration which allows slightly better airflow to the rear runners than the front ones. The positioning of the auxillary injectors takes this into consideration. The extra injectors also only kick in when the stock fuel system is maxed out. Once again, HKS designed this kit to work with the stock engine, be a street system, and be emissions compliant. It is not meant to be a "starting point" for a mega-power build-up.
Anyway....my car goes in today to XXtuning for the install. We will do a baseline dyno run this morning. The install *should* be done by Thursday morning. I want to then drive the car for several hundred miles to allow the SC to fully break in before re-dynoing.
Registered User
Joined: Sep 2003
Posts: 585
Likes: 0
From: Jersey
Are there goining to be pulley upgrades for this s/c? how much psi is the compressor good for? I'm really looking into this kit, if this s/c is capable of 400-450 whp I think I may be sold on this kit also.
Re: Here's what I kow on the fueling issue.....
Originally posted by Speedracer
Anyway....my car goes in today to XXtuning for the install. We will do a baseline dyno run this morning. The install *should* be done by Thursday morning. I want to then drive the car for several hundred miles to allow the SC to fully break in before re-dynoing.
Anyway....my car goes in today to XXtuning for the install. We will do a baseline dyno run this morning. The install *should* be done by Thursday morning. I want to then drive the car for several hundred miles to allow the SC to fully break in before re-dynoing.
I think the simple reason they chose not to do 6 aux injectors was cost and reprgramming. By having the 2 additional injectors be load dependant and placing them in the plenum (closer to the combustion chamber), I think they take alot of the risk out while keeping the cost down adn the mapping relatively simple for them. gien the power this kit puts out out of the box,this seems to be a very logical solution
Originally posted by APS
Tweety-nator, warning - long post
You have raised a number of interesting points that can be confusing to some because we are dealing with many issues - at the same time - that contribute to engine performance and durability. I’m also mindful of not steering this thread off-topic so my apologies in advance.
Regardless of the form of FI, engine tuning parameters and fuel quality are of paramount importance. This can make the difference of an engine surviving at 9 psi of boost versus another identical engine failing at 6 psi.
With a turbocharger system that employs advanced boost mapping, the exact boost pressure can be programmed throughout the RPM range. This way, the boost pressure is at the optimum level at each point in the RPM range. There’s no need to forsake boost at say 3,000 rpm if the engine is capable of handling it. Naturally, it would be foolhardy to program too much boost pressure at that point. The same applies anywhere else in the RPM range.
As an aside, we can map the boost pressure vs RPM on the TT system to mimic the boost profile of a supercharger – it basically involves removing boost in the low and mid RPM range.
I’m also always mindful of comparing power figures and relating them back to engine durability. A supercharger for example that produces 320 hp requires the engine to produce some 30 to 40 additional hp because of the parasitic nature of a supercharger and the fact that the supercharger consumes that amount of power from the engine to drive it. An equivalent turbocharger system on the other hand would be producing 320 + 30 to 40 hp (because a turbo is not parasitic). So it would be remiss of me to think that the higher power figure would be less reliable because the engine is in fact under the same amount of load to produce the two different hp figures.
To put this another way, with the two vehicles producing the same hp, the turbocharged engine would be under less load than the supercharged engine because the turbo doesn’t need the engine to produce 30 – 40 hp more to achieve the same hp result.
I guess what I’m trying to say is that we’re all very mindful of engine durability. Given the correct ignition timing map, air/fuel ratio map and boost pressure map set at a reasonable 6 – 7 psi maximum – with the engine running on good quality fuel - the likelihood of engine failure is fairly small regardless of the type of FI used. It’s just that more power makes it to the wheels when it doesn’t have to drive a supercharger.
Now back to the rods. I think it's fair to say that over the years I've broken my fair share of rods in supercharged and turbocharged engines.
There are three common reasons for rod failure that I'm aware of. They are exceeding the mechanical structural properties of the rod (and in this instance you normally bend the rod, not break it)
Next is increased engine RPM. On some engines RPM increases of only 300 RPM over stock will break a rod every time. I would be very mindful of raising the RPM limit on either a supercharged or turbocharged engine at elevated power levels.
Thirdly, if the big end bearing fails (the top bearing shell can be hammered and damaged through high mechanical shock loads caused by detonation) and invariably spins - thus creating enormous thermal loads due to friction. Consequently, the rod breaks at the big end. This type of failure has nothing to do with the mechanical strength of the rod, but often the rod is blamed for being weak - which is obviously not the case in this type of failure. It all comes down to correct diagnosis.
We all know that power in the 350Z is highly addictive - no matter where in the RPM range power is produced. Let’s face it, when an enthusiast has the ability to up the boost, he generally does at some point or another. There’s an old motto that goes something like this - Crank up the boost until something breaks and then turn it back half a psi.
Happy and responsible boosting to all - it's all about the fun factor!
This is one of the many reason why I chose APS TT to be the FI in my car, Peter talk on a language that I can understand.
Peter
Tweety-nator, warning - long post
You have raised a number of interesting points that can be confusing to some because we are dealing with many issues - at the same time - that contribute to engine performance and durability. I’m also mindful of not steering this thread off-topic so my apologies in advance.
Regardless of the form of FI, engine tuning parameters and fuel quality are of paramount importance. This can make the difference of an engine surviving at 9 psi of boost versus another identical engine failing at 6 psi.
With a turbocharger system that employs advanced boost mapping, the exact boost pressure can be programmed throughout the RPM range. This way, the boost pressure is at the optimum level at each point in the RPM range. There’s no need to forsake boost at say 3,000 rpm if the engine is capable of handling it. Naturally, it would be foolhardy to program too much boost pressure at that point. The same applies anywhere else in the RPM range.
As an aside, we can map the boost pressure vs RPM on the TT system to mimic the boost profile of a supercharger – it basically involves removing boost in the low and mid RPM range.
I’m also always mindful of comparing power figures and relating them back to engine durability. A supercharger for example that produces 320 hp requires the engine to produce some 30 to 40 additional hp because of the parasitic nature of a supercharger and the fact that the supercharger consumes that amount of power from the engine to drive it. An equivalent turbocharger system on the other hand would be producing 320 + 30 to 40 hp (because a turbo is not parasitic). So it would be remiss of me to think that the higher power figure would be less reliable because the engine is in fact under the same amount of load to produce the two different hp figures.
To put this another way, with the two vehicles producing the same hp, the turbocharged engine would be under less load than the supercharged engine because the turbo doesn’t need the engine to produce 30 – 40 hp more to achieve the same hp result.
I guess what I’m trying to say is that we’re all very mindful of engine durability. Given the correct ignition timing map, air/fuel ratio map and boost pressure map set at a reasonable 6 – 7 psi maximum – with the engine running on good quality fuel - the likelihood of engine failure is fairly small regardless of the type of FI used. It’s just that more power makes it to the wheels when it doesn’t have to drive a supercharger.
Now back to the rods. I think it's fair to say that over the years I've broken my fair share of rods in supercharged and turbocharged engines.
There are three common reasons for rod failure that I'm aware of. They are exceeding the mechanical structural properties of the rod (and in this instance you normally bend the rod, not break it)
Next is increased engine RPM. On some engines RPM increases of only 300 RPM over stock will break a rod every time. I would be very mindful of raising the RPM limit on either a supercharged or turbocharged engine at elevated power levels.
Thirdly, if the big end bearing fails (the top bearing shell can be hammered and damaged through high mechanical shock loads caused by detonation) and invariably spins - thus creating enormous thermal loads due to friction. Consequently, the rod breaks at the big end. This type of failure has nothing to do with the mechanical strength of the rod, but often the rod is blamed for being weak - which is obviously not the case in this type of failure. It all comes down to correct diagnosis.
We all know that power in the 350Z is highly addictive - no matter where in the RPM range power is produced. Let’s face it, when an enthusiast has the ability to up the boost, he generally does at some point or another. There’s an old motto that goes something like this - Crank up the boost until something breaks and then turn it back half a psi.
Happy and responsible boosting to all - it's all about the fun factor!
This is one of the many reason why I chose APS TT to be the FI in my car, Peter talk on a language that I can understand.
Peter
Peter and APS RULES!!!!!
Registered User
Joined: Apr 2004
Posts: 416
Likes: 0
From: Houston, Tx
Originally posted by Tweety-nator
You are right, a FI car will definitely require better upkeep. I guess I am just disappointed that they used an inferior filter element on an otherwise well designed kit.
You are right, a FI car will definitely require better upkeep. I guess I am just disappointed that they used an inferior filter element on an otherwise well designed kit.
Registered User
Joined: Apr 2004
Posts: 416
Likes: 0
From: Houston, Tx
Originally posted by shopdog
Actually, you can bring a kit with you and check the specific gravity of the fuel. It isn't difficult to do, and if you are travelling outside the US it might be a good idea. But if you're buying fuel in the US, your state government does tests to enforce the octane numbers posted on the pumps. All you need do is read that number and select the proper grade.
Now Nissan tells us to use premium fuel even in the stock NA engine. While you can sometimes "get away" with using a lower grade occasionally, you will more likely get pinging, knocking, and for sure reduced performance if you do. Once you start boosting the motor even a little, 87 octane fuel is right out, 91 octane is marginal, and 93 octane works well for moderate boost levels. At high boost, race gas is the only option.
You can't realistically expect the kit makers to design their kits so they'll work on 70 octane gas left over from WWII and pumped out of a rusty 55 gallon barrel. There has to be a realistic expectation that you'll use fuel at least as good as Nissan recommends for the stock engine.
Actually, you can bring a kit with you and check the specific gravity of the fuel. It isn't difficult to do, and if you are travelling outside the US it might be a good idea. But if you're buying fuel in the US, your state government does tests to enforce the octane numbers posted on the pumps. All you need do is read that number and select the proper grade.
Now Nissan tells us to use premium fuel even in the stock NA engine. While you can sometimes "get away" with using a lower grade occasionally, you will more likely get pinging, knocking, and for sure reduced performance if you do. Once you start boosting the motor even a little, 87 octane fuel is right out, 91 octane is marginal, and 93 octane works well for moderate boost levels. At high boost, race gas is the only option.
You can't realistically expect the kit makers to design their kits so they'll work on 70 octane gas left over from WWII and pumped out of a rusty 55 gallon barrel. There has to be a realistic expectation that you'll use fuel at least as good as Nissan recommends for the stock engine.
Registered User
Joined: Apr 2004
Posts: 416
Likes: 0
From: Houston, Tx
Originally posted by APS
I'm not at all concerned with the load reference (map sensor) utilised to control the 2 additional fuel injectors or even the fuel flow (size of the 2 additional injectors)................what concerns me is that this approach cannot provide perfect fuel delivery to all 6 cylinders equally.
Some cylinders could be overly rich whilst other cylinders could be very lean (this can cause detonation and elevated exhaust gas temperatures on the lean cylinders)................not an ideal approach on FI engines.................6 larger fuel injectors which replace the 6 stock Nissan fuel injectors is the best and safest method for all high performance FI engines.
If I were to install an HKS supercharger system to a Z engine I would definitely recommend replacing the 2 aux injectors supplied in the HKS supercharger system with 6 larger injectors which mount in the factory nissan plenum position.
Better to be safe than sorry.
Peter
APS
I'm not at all concerned with the load reference (map sensor) utilised to control the 2 additional fuel injectors or even the fuel flow (size of the 2 additional injectors)................what concerns me is that this approach cannot provide perfect fuel delivery to all 6 cylinders equally.
Some cylinders could be overly rich whilst other cylinders could be very lean (this can cause detonation and elevated exhaust gas temperatures on the lean cylinders)................not an ideal approach on FI engines.................6 larger fuel injectors which replace the 6 stock Nissan fuel injectors is the best and safest method for all high performance FI engines.
If I were to install an HKS supercharger system to a Z engine I would definitely recommend replacing the 2 aux injectors supplied in the HKS supercharger system with 6 larger injectors which mount in the factory nissan plenum position.
Better to be safe than sorry.
Peter
APS
Thread
Thread Starter
Forum
Replies
Last Post
Lt_Ballzacki
Brakes & Suspension
39
Aug 6, 2021 06:19 AM
350Z_Al
Exterior & Interior
133
Oct 29, 2020 07:44 PM
ars88
Zs & Gs For Sale
18
Apr 4, 2016 07:52 AM