Gen 5 fuel pump questions

[Custom 68]

Hi all, I know a few have done the gen 5 swap so my question is how do you turn on the fuel pump. I am not going to jump into the PWM setup at this time but hoped to be able to use a pump similar to how the ls style is done. I don't find a way.
I assume most are just powering off of a key on accessory and it runs all the time. I can add an oil pressure sensor to shut off the pump when the motor is not running for safety which is probably what I will do. What else has been done?
Thanks,
Dave

[Richard]

Originally Posted by Custom 68

Hi all, I know a few have done the gen 5 swap so my question is how do you turn on the fuel pump. I am not going to jump into the PWM setup at this time but hoped to be able to use a pump similar to how the ls style is done. I don't find a way.
I assume most are just powering off of a key on accessory and it runs all the time. I can add an oil pressure sensor to shut off the pump when the motor is not running for safety which is probably what I will do. What else has been done?
Thanks,
Dave

Curious why to avoid pwm? Uses stock oem pump, more reliable, easier to install in some ways (no return) and cost ends up about the same as an aftermarket return style system. Benefits to loosing the recirc system as well, less fuel heat, longer pump life and lower amps to fuel pump required during normal daily driving. Used the Vaporworx controller on my LSA with their super fuel module. Really just a CTSv fuel module which is no longer available from GM.
The Vaporworx controller in my system is shut on and off by the ECU. I get a prime function and pump will shut off when engine is not running.

[Joyridin]

Originally Posted by Custom 68

Hi all, I know a few have done the gen 5 swap so my question is how do you turn on the fuel pump. I am not going to jump into the PWM setup at this time but hoped to be able to use a pump similar to how the ls style is done. I don't find a way.
I assume most are just powering off of a key on accessory and it runs all the time. I can add an oil pressure sensor to shut off the pump when the motor is not running for safety which is probably what I will do. What else has been done?
Thanks,
Dave

When the harness was reworked, there is a relay specifically for the electric fuel pump. I just ran it from there.

Realistically, all you have to do is pull a small keyed voltage off the switch, computer, or fuse box to a relay. Let the relay carry the load.

I mounted all the hoses etc at the back of the vehicle (tank in rear) and only have a feed line going up front. It was easy and after 4 years and thousands of miles, no problems at all.

[LS short box]

On my LS swaps the fuel pump was controlled by the ECM. When you turn the key on the ECM triggers the fuel pump thru a relay but if the ECM doesn't see crank rotation it shuts down the fuel pump after a few seconds.
I wonder what fuel PSI is needed since the direct injection engines have the "high" pressure fuel pump powered by a lobe on the cam shaft?
I think I would ask the same question over on LS1tech.com.

[Joyridin]

I have mine set at 65psi, but it was originally at 58 psi and ran fine. I do not have turbos or anything.

[Custom 68]

Originally Posted by Richard

Curious why to avoid pwm? Uses stock oem pump, more reliable, easier to install in some ways (no return) and cost ends up about the same as an aftermarket return style system. Benefits to loosing the recirc system as well, less fuel heat, longer pump life and lower amps to fuel pump required during normal daily driving. Used the Vaporworx controller on my LSA with their super fuel module. Really just a CTSv fuel module which is no longer available from GM.
The Vaporworx controller in my system is shut on and off by the ECU. I get a prime function and pump will shut off when engine is not running.

Thank you Richard and everybody that posted. I put this out there then had an out of town commitment but now I am back.
I am not opposed to the PWN setup I know GM made the changes for all those listed reasons. I got a bit lost when I was trying to sort out the all GM parts and make it work. it seemed the pressure sensor and all got a bit tricky. I will look into the Vaproworx, I have seen this referenced quite a bit and know it is a good setup.
The other reason is the cost. The engine I am working with is an LV3 so it is the gen 5 but the 6 cylinder version. I was intrigued several years ago and found one on the cheap locally. I know the swap is not cheap but chose to give this a try rather than an ls motor. I modified the harness and had it running on my chassis but nothing more. I wanted to get this running before I spent a ton more money. The PWM may be in the future for my build or this 6 cylinder may go to the wayside. All my reading indicates the pwm is the best but I have read a constant pressure seems to work just as well.
I will do more digging on teh pwm setup.
Thanks,
Dave

[Custom 68]

Originally Posted by Joyridin

When the harness was reworked, there is a relay specifically for the electric fuel pump. I just ran it from there.

Realistically, all you have to do is pull a small keyed voltage off the switch, computer, or fuse box to a relay. Let the relay carry the load.

I mounted all the hoses etc at the back of the vehicle (tank in rear) and only have a feed line going up front. It was easy and after 4 years and thousands of miles, no problems at all.

Originally Posted by LS short box

On my LS swaps the fuel pump was controlled by the ECM. When you turn the key on the ECM triggers the fuel pump thru a relay but if the ECM doesn't see crank rotation it shuts down the fuel pump after a few seconds.
I wonder what fuel PSI is needed since the direct injection engines have the "high" pressure fuel pump powered by a lobe on the cam shaft?
I think I would ask the same question over on LS1tech.com.

Originally Posted by Joyridin

I have mine set at 65psi, but it was originally at 58 psi and ran fine. I do not have turbos or anything.

thanks for the replies, I reworked my harness and have the wire for the pwm control but had not sorted out if it could be used to control just a relay. My ls swap does the same thing, key on it will prime then if or when the engine dies it will shut off. That was the ease and safety I was looking for. I know this is not the best way but it seems to work. I didn't want to just wire the relay up to the key on switch mainly for safety.
I am still aways out on getting this all together as it is a full restore on a 1971 Camaro.

Thanks again,
Dave