Lean Spot At ~2400 RPM...What the?
09-04-2010, 06:27 PM
#121
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and?
my car is jerky and the vac map sucks for drivability now....i don't want to go through all the hell you went through with replacing tons of parts if it's something simple. I'm thinking fuel injectors but that wasn't your issue.
my car is jerky and the vac map sucks for drivability now....i don't want to go through all the hell you went through with replacing tons of parts if it's something simple. I'm thinking fuel injectors but that wasn't your issue.
09-05-2010, 11:18 AM
#123
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https://my350z.com/forum/forced-indu...o-setup-6.html
page 5 and 6. Started when i switched from vortech to turbo. FIrst thing i changed was the injectors and it started running bad but then i figured it was my tune so i did my complete change over. Even hal couldn't get it to tune out smooth. Something weird is going on.
page 5 and 6. Started when i switched from vortech to turbo. FIrst thing i changed was the injectors and it started running bad but then i figured it was my tune so i did my complete change over. Even hal couldn't get it to tune out smooth. Something weird is going on.
09-07-2010, 08:54 AM
#124
Do a datalog. Turn the O2 control off and try to accelerate from 1000 to ~3500 rpm while maintaining about 16-18 inches of vacuum. If the A/F trace looks like this:
https://my350z.com/forum/attachments...ean-spot-2.jpg
Then you probably have the same problem I had.
https://my350z.com/forum/attachments...ean-spot-2.jpg
Then you probably have the same problem I had.
Last edited by mx594; 09-07-2010 at 08:56 AM.
09-09-2010, 09:51 PM
#127
He made his own and the problem was resolved.
We have a batch coming up and will be sending him the production part. We will keep them around for any customers that experience the same issue. We dont expect to see much of it, but we want to be able to take care of it for people if it happens to them.
We also are going to be making a part to add it to our stage 1-3 kits that use our rails, incase someone has that issue with one of those kits. It appears Binder may be experiencing it as well.
We find it very strange since we have hundreds of kits out there for about 6 years now... but it is what it is and its not the customers fault. I wish we could adapt to it quicker but we will have these parts out soon.
We have a batch coming up and will be sending him the production part. We will keep them around for any customers that experience the same issue. We dont expect to see much of it, but we want to be able to take care of it for people if it happens to them.
We also are going to be making a part to add it to our stage 1-3 kits that use our rails, incase someone has that issue with one of those kits. It appears Binder may be experiencing it as well.
We find it very strange since we have hundreds of kits out there for about 6 years now... but it is what it is and its not the customers fault. I wish we could adapt to it quicker but we will have these parts out soon.
09-10-2010, 09:25 AM
#128
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ya, from the sounds of it you and me both have the same dead spots in the curve charles with our HKS injectors. Maybe it will benefit your car as well.
i would definitely appreciate this part to test and see if this might be an issue with mine. I'm out of my mind trying to figure out my fuel pressure issues.
I haven't heard back from you charles but i hope you got my email with the tests i performed on my twin pump. I don't think it's an issue with the twin pump itself.
i would definitely appreciate this part to test and see if this might be an issue with mine. I'm out of my mind trying to figure out my fuel pressure issues.
I haven't heard back from you charles but i hope you got my email with the tests i performed on my twin pump. I don't think it's an issue with the twin pump itself.
09-13-2010, 09:04 AM
#131
The fix is to add a damper back into the fuel system. The problem was caused by resonance in the fuel, as a result of removing the damper to install the fuel return adapter. I designed and fabricated a new return adapter that allows the damper to be retained. With the damper bolted back on, the problem is gone.
It appears that I am still getting a very small amount of resonance at 1500, 2000 and 3000 rpm now. But the huge A/F spikes at 1200, 1600, and 2400 are completely gone. The car runs well enough now that I have driven it almost every day for the last month.
I would still like to try putting the FPR before the fuel rail, and leaving the rails/dampers alone. This would also allow the FPR to smooth out any pressure fluctuations from the pump before they get to the rails, rather than after. If you think about it, that is how the stock setup works...
It appears that I am still getting a very small amount of resonance at 1500, 2000 and 3000 rpm now. But the huge A/F spikes at 1200, 1600, and 2400 are completely gone. The car runs well enough now that I have driven it almost every day for the last month.
I would still like to try putting the FPR before the fuel rail, and leaving the rails/dampers alone. This would also allow the FPR to smooth out any pressure fluctuations from the pump before they get to the rails, rather than after. If you think about it, that is how the stock setup works...
09-13-2010, 11:16 AM
#133
Even with the problem only reported effecting less than 1% of several hundred RFS we have sold, we are going to update our stage 0 fitting for all future kits to accommodate the damper.
For our stage 1-3 kits it's a little more complicated and requires extra parts. We will offer an optional damper add on for the customers that experience these issues with their high HP setups.
Fuel pressure pulsations are mostly related to the injectors opening and closing, somewhat like intake manifold resonances caused by the valves opening and closing. The goal is to keep the damper as near the rails, ideally on the rails, as found in most oem applications that include dampers. That is what will be te tricky part for people using billet rails in our systems or anyone elses fuel systems (all rfs made for this vehicle have always eliminated dampers)
For our stage 1-3 kits it's a little more complicated and requires extra parts. We will offer an optional damper add on for the customers that experience these issues with their high HP setups.
Fuel pressure pulsations are mostly related to the injectors opening and closing, somewhat like intake manifold resonances caused by the valves opening and closing. The goal is to keep the damper as near the rails, ideally on the rails, as found in most oem applications that include dampers. That is what will be te tricky part for people using billet rails in our systems or anyone elses fuel systems (all rfs made for this vehicle have always eliminated dampers)
09-13-2010, 01:44 PM
#134
Even with the problem only reported effecting less than 1% of several hundred RFS we have sold, we are going to update our stage 0 fitting for all future kits to accommodate the damper.
For our stage 1-3 kits it's a little more complicated and requires extra parts. We will offer an optional damper add on for the customers that experience these issues with their high HP setups.
Fuel pressure pulsations are mostly related to the injectors opening and closing, somewhat like intake manifold resonances caused by the valves opening and closing. The goal is to keep the damper as near the rails, ideally on the rails, as found in most oem applications that include dampers. That is what will be te tricky part for people using billet rails in our systems or anyone elses fuel systems (all rfs made for this vehicle have always eliminated dampers)
For our stage 1-3 kits it's a little more complicated and requires extra parts. We will offer an optional damper add on for the customers that experience these issues with their high HP setups.
Fuel pressure pulsations are mostly related to the injectors opening and closing, somewhat like intake manifold resonances caused by the valves opening and closing. The goal is to keep the damper as near the rails, ideally on the rails, as found in most oem applications that include dampers. That is what will be te tricky part for people using billet rails in our systems or anyone elses fuel systems (all rfs made for this vehicle have always eliminated dampers)
The way I see it, you can't have too much damping. I still need more I think.
09-14-2010, 09:13 AM
#135
they sell dampers for aftermarket fuel rails.
These are ~50$
http://www.matronics.com/fuelchec/damper.html
or theses like $115
http://www.injector.com/cart/pc/view...H&idCategory=4
pretty wild that's the solution, pretty rare occurance it seems...
These are ~50$
http://www.matronics.com/fuelchec/damper.html
or theses like $115
http://www.injector.com/cart/pc/view...H&idCategory=4
pretty wild that's the solution, pretty rare occurance it seems...
09-14-2010, 09:33 AM
#136
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how does that first sphere one work? It doesn't list a diaphragm in it so wouldn't it just fill up with fuel also and do nothing? I don't see how they keep air in it with no diaphragm.
09-14-2010, 10:52 AM
#137
Even with the problem only reported effecting less than 1% of several hundred RFS we have sold, we are going to update our stage 0 fitting for all future kits to accommodate the damper.
For our stage 1-3 kits it's a little more complicated and requires extra parts. We will offer an optional damper add on for the customers that experience these issues with their high HP setups.
Fuel pressure pulsations are mostly related to the injectors opening and closing, somewhat like intake manifold resonances caused by the valves opening and closing. The goal is to keep the damper as near the rails, ideally on the rails, as found in most oem applications that include dampers. That is what will be te tricky part for people using billet rails in our systems or anyone elses fuel systems (all rfs made for this vehicle have always eliminated dampers)
For our stage 1-3 kits it's a little more complicated and requires extra parts. We will offer an optional damper add on for the customers that experience these issues with their high HP setups.
Fuel pressure pulsations are mostly related to the injectors opening and closing, somewhat like intake manifold resonances caused by the valves opening and closing. The goal is to keep the damper as near the rails, ideally on the rails, as found in most oem applications that include dampers. That is what will be te tricky part for people using billet rails in our systems or anyone elses fuel systems (all rfs made for this vehicle have always eliminated dampers)
09-14-2010, 01:29 PM
#138
09-14-2010, 03:53 PM
#140
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I've also got a weird knocking sound after fitting my CJM stage 3. It sounds like a series of taps (say 2-4) when you touch the accellerator from idle. I originally thought it was from the reg on the firewall but after temporarily unbolting it and zip tying it out the way found that not to be the case. Furthur inspection leads me to believe its from around the rails themselves. I've sort of got used to it but it is annoying. I'm going to remove the plenum and check it out when I have time to start my wire tuck but until then can't be assed 
When Charles makes up the adaptors I'll get one just for peice of mind and with a hope it may resolve my strange noise.
I like the reg bracket mx594. Might have to get one made locally. Might reduce the fuel flow noise a little.
Matt
When Charles makes up the adaptors I'll get one just for peice of mind and with a hope it may resolve my strange noise.
I like the reg bracket mx594. Might have to get one made locally. Might reduce the fuel flow noise a little.
Matt