Do i need a bigger regulator?
Thanks for the insight guys. I think the easiest option here is to unhook the vacuum line and set BFP to 43. Have one pump run in all the time and stage the second one around 15psi or so.
Blown 06 faced a lot of these issues with his old regulator and I will try this first.
FF I do like the PWM setup and remember ZB posting about it. I'll shoot him a message and see if it's holding up.
Colt, as far as vacuum source is concerned I have no issues with it being fed off the vacuum block as the block is being fed with a 1/2" line. There is plenty of air being fed through that thing..
Now just for fun check out this video! First street test against a nitrous C6Z
Blown 06 faced a lot of these issues with his old regulator and I will try this first.
FF I do like the PWM setup and remember ZB posting about it. I'll shoot him a message and see if it's holding up.
Colt, as far as vacuum source is concerned I have no issues with it being fed off the vacuum block as the block is being fed with a 1/2" line. There is plenty of air being fed through that thing..
Now just for fun check out this video! First street test against a nitrous C6Z
I’m sure he could PWM both. But the PWM SS relays aren’t cheap. I believe they too get hot when you run them at excessively low frequencies. Even at lowish PWM Freq.’s, I’d imagine 2 pumps would push excessive amounts of fuel for idle/cruise.
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Joined: Nov 2003
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From: Norn Iron
Not sure, It was never a big enough problem for me to measure fluid temps. The pump body itself was hot enough to scald me on a hot summer day after a 45 mile cruise though. No blister, but I reached down and grabbed the pump thinking it would be warm…sucker was hot! Pump hangs down in the airflow as well. Using ½” SS hard lines supply and return.
I’m sure he could PWM both. But the PWM SS relays aren’t cheap. I believe they too get hot when you run them at excessively low frequencies. Even at lowish PWM Freq.’s, I’d imagine 2 pumps would push excessive amounts of fuel for idle/cruise.
I’m sure he could PWM both. But the PWM SS relays aren’t cheap. I believe they too get hot when you run them at excessively low frequencies. Even at lowish PWM Freq.’s, I’d imagine 2 pumps would push excessive amounts of fuel for idle/cruise.
But some do say not to go lower than around 50% duty, but it does vary from pump to pump. And given most SSR's are 40-80A, a single relay would do fine for both pumps
But yes, they need a heat sink regardless.
Again, keeps it all simple with 1 relay. If it fails, the car stops. If 1 relay fails on a 2 relay/2 pump setup...that carries risks to the engine if you have no failsafes to fall back on.
And pump temperature isnt necessarily an indication of fuel temperature, especially if the motor is isolated from the pump section.
Why would that cause it not to rise at the correct rate? A small return orifice would just show as an issue if pressure could not be LOWERED to your target.
To the OP- 2 things
1) Test it with the car not running. Build a little rig so you can pressurize it with an air hose. This will tell you if its a regulator issue, or a SIGNAL issue.
2) Most regulators I have seen do not give a true 1 to 1 rise, even the high dollar ones. If you are not ruining out of fuel, I would not worry about it as long as it rises in a consistent fashion.
3) If you test it and it shows true 1 to 1, make sure you a have a TRUE and dedicated signal line off the source, not off a vacuum block or "T" line. I cant tell you hoe many times I have changed this out of customer cars with FP issues and cured the problem.
To the OP- 2 things
1) Test it with the car not running. Build a little rig so you can pressurize it with an air hose. This will tell you if its a regulator issue, or a SIGNAL issue.
2) Most regulators I have seen do not give a true 1 to 1 rise, even the high dollar ones. If you are not ruining out of fuel, I would not worry about it as long as it rises in a consistent fashion.
3) If you test it and it shows true 1 to 1, make sure you a have a TRUE and dedicated signal line off the source, not off a vacuum block or "T" line. I cant tell you hoe many times I have changed this out of customer cars with FP issues and cured the problem.
Testing the system with air just shows that it works.......it working with a given amount of volume of fuel moving through the system proved to be a different story all together.
Thanks for the insight guys. I think the easiest option here is to unhook the vacuum line and set BFP to 43. Have one pump run in all the time and stage the second one around 15psi or so.
Blown 06 faced a lot of these issues with his old regulator and I will try this first.
FF I do like the PWM setup and remember ZB posting about it. I'll shoot him a message and see if it's holding up.
Colt, as far as vacuum source is concerned I have no issues with it being fed off the vacuum block as the block is being fed with a 1/2" line. There is plenty of air being fed through that thing..
Now just for fun check out this video! First street test against a nitrous C6Z
Magic280z - YouTube
Blown 06 faced a lot of these issues with his old regulator and I will try this first.
FF I do like the PWM setup and remember ZB posting about it. I'll shoot him a message and see if it's holding up.
Colt, as far as vacuum source is concerned I have no issues with it being fed off the vacuum block as the block is being fed with a 1/2" line. There is plenty of air being fed through that thing..
Now just for fun check out this video! First street test against a nitrous C6Z
Magic280z - YouTube
Thanks for the insight guys. I think the easiest option here is to unhook the vacuum line and set BFP to 43. Have one pump run in all the time and stage the second one around 15psi or so.
Blown 06 faced a lot of these issues with his old regulator and I will try this first.
FF I do like the PWM setup and remember ZB posting about it. I'll shoot him a message and see if it's holding up.
Colt, as far as vacuum source is concerned I have no issues with it being fed off the vacuum block as the block is being fed with a 1/2" line. There is plenty of air being fed through that thing..
Now just for fun check out this video! First street test against a nitrous C6Z
Magic280z - YouTube
Blown 06 faced a lot of these issues with his old regulator and I will try this first.
FF I do like the PWM setup and remember ZB posting about it. I'll shoot him a message and see if it's holding up.
Colt, as far as vacuum source is concerned I have no issues with it being fed off the vacuum block as the block is being fed with a 1/2" line. There is plenty of air being fed through that thing..
Now just for fun check out this video! First street test against a nitrous C6Z
Magic280z - YouTube
FYI pulling the vacuum line and staging the second pump at 15psi worked like a charm. With a BFP at 43psi I am seeing 1:1 with boost. No need for a big expensive regulator.
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I've ran two 4303's full time with E85 for two seasons now.
I also run the magnafuel regulator. My Holley EFI logs show consistent .95:1 FP increases. Just shy of true 1:1. Sometimes it hits true 1:1.
Both pumps are their own AN12 from the dual sump outlets. Then Each Pump has AN10 to a Yblock with a single AN10outlet. That single AN10 line is ran all the way to another Yblock at the firewall. Where it splits into AN8 rail feeds. I have a AN10 return line to the tank.
I like not having a Hobbs switch for the second pump to kick on. It's just a really simple set up and easy to troubleshoot with issues. I will say with both pumps on all the time don't ever let the tank get below half way full. It seems like when I do that they start acting really funny.
I also run the magnafuel regulator. My Holley EFI logs show consistent .95:1 FP increases. Just shy of true 1:1. Sometimes it hits true 1:1.
Both pumps are their own AN12 from the dual sump outlets. Then Each Pump has AN10 to a Yblock with a single AN10outlet. That single AN10 line is ran all the way to another Yblock at the firewall. Where it splits into AN8 rail feeds. I have a AN10 return line to the tank.
I like not having a Hobbs switch for the second pump to kick on. It's just a really simple set up and easy to troubleshoot with issues. I will say with both pumps on all the time don't ever let the tank get below half way full. It seems like when I do that they start acting really funny.
Glad to see you got it figured out! All this great information will hopefully make my life easier when I am at this point. 
Are you sure the Z06 was actually racing you and not just along to video your car pulling away?
Are you sure the Z06 was actually racing you and not just along to video your car pulling away?
I've ran two 4303's full time with E85 for two seasons now.
I also run the magnafuel regulator. My Holley EFI logs show consistent .95:1 FP increases. Just shy of true 1:1. Sometimes it hits true 1:1.
Both pumps are their own AN12 from the dual sump outlets. Then Each Pump has AN10 to a Yblock with a single AN10outlet. That single AN10 line is ran all the way to another Yblock at the firewall. Where it splits into AN8 rail feeds. I have a AN10 return line to the tank.
I like not having a Hobbs switch for the second pump to kick on. It's just a really simple set up and easy to troubleshoot with issues. I will say with both pumps on all the time don't ever let the tank get below half way full. It seems like when I do that they start acting really funny.
I also run the magnafuel regulator. My Holley EFI logs show consistent .95:1 FP increases. Just shy of true 1:1. Sometimes it hits true 1:1.
Both pumps are their own AN12 from the dual sump outlets. Then Each Pump has AN10 to a Yblock with a single AN10outlet. That single AN10 line is ran all the way to another Yblock at the firewall. Where it splits into AN8 rail feeds. I have a AN10 return line to the tank.
I like not having a Hobbs switch for the second pump to kick on. It's just a really simple set up and easy to troubleshoot with issues. I will say with both pumps on all the time don't ever let the tank get below half way full. It seems like when I do that they start acting really funny.
Its very strange to me that you basically ran the same set up as me yet yours worked and mine did not and required the larger regulator. The only difference I can see is that I Y'd both pumps into a -12 line and then Y'd it back off to -10's to feed each rail with a -10 back to the tank. I'm wondering if the size difference in our lines put mine just over the threshold of flowing too much fuel at idle for the regulator to stay in it's usable range for adjustment. Really would be the only explanation other than I also had both pumps wired very well with high quality TXL 10 gauge wiring on both + and - with the whole loop only being four feet long direct from the battery. Could have been a combination of both things and in my opinion could be a leason to others showing what good wiring practices and lines sizes can do to increase pump performance.