dhutton

iTrader: (1)

Is it possible to rework the stock harness and retain the fuel pump controller etc? Can the ECU be programmed with basic standalone settings to delete VATS etc? Speartech uses new injectors, new ECU etc for their LSA swap harness and they will not rework LSA harnesses. They also do not use the stock fuel pump and controller.

Don

Project GatTagO

iTrader: (7)

Don,

I don't have answers to your questions, but GM does offer a standalone LSA harness and ECU package.

Andrew

dhutton

iTrader: (1)

Yes they do but it has some off the wall fuel pressure requirements that are not easily met. 65 psi at idle. 85 psi max with boost reference. Coming up with a fuel system like this is not trivial, hence my thinking to somehow use the stock CTS-V fuel controller and fuel pump. It also does not allow the use of the 6L90e transmission so lots of compromises there.

The harness and ECU come "free" with a used package. I am trying to see if they can be used to reproduce the stock control systems.

Thanks,
Don

Project GatTagO

iTrader: (7)

LSA idle fuel pressure is 58, just like all other LS engines:

http://www.chevrolet.com/content/dam...e-19260164.pdf

See page 2.

But you're right, a take out harness is free and if it can be reworked, then that's the way to go.

Andrew

dhutton

iTrader: (1)

There seems to be a lot of confusion out there. Check out this part number which is the actual controller: 19259293. Requirements are as I stated. I guess I could try calling them but I am not too hopeful on that.

http://www.chevrolet.com/content/dam...d-19259293.pdf

Thanks,
Don

dhutton

iTrader: (1)

Got the GM tech line number from Pace and called them. The requirement is as i quoted, 65 to 85 boost referenced. Tough to do....

He said the data sheet you have is out of date.

Don

garys 68

iTrader: (1)

They don't exactly flood you with info there.
Stupid question....
If an LSA puts out 9-10 psi and a vacuum reading of 18" of Hg = about 9 psi below atmospheric pressure. Couldn't you just use an efi boost/vacuum referenced regulator set at 65 at idle and let it increase fuel pressure abot 19-20 psi to about 85psi at WOT (10psi boost)?

kwhizz

Heres what I used on my LSA conversion.........Not a single issue

http://www.vaporworx.com/


Ken

dhutton

iTrader: (1)

That is what I was considering. Trouble is I don't want to have the pump heating up the fuel since it will need to be something like a Walbro 400. I have heard they do not last long with any kind of PCM control.

Other issue is I wanted to run a Vapor Works tank and he has already told me that he does not have a solution for those requirements.

Thanks,
Don

dhutton

iTrader: (1)

Thanks Ken. Did you swap out the injectors? Were you using an LSA crate or a used setup? What controller are you using, the GM Performance or something like the Speartech? What fuel pressure are you running? Carl told me he did not have a solution for the requirements listed on the controller instructions.

Thanks,
Don

S10xGN

iTrader: (11)

I'm not a tuning guru, but what the heck difference does the fuel pressure make when you can size the injectors accordingly? If you have a big enough injector that will correctly atomize fuel, you could run 20 PSI normally aspirated with boost reference raising FP incrementally...

dhutton

iTrader: (1)

The goal here is to avoid changing the injectors. Yes, I could change them but that is not my goal. I want to run it as is. No tuning etc needed then.

Thanks,
Don

Project GatTagO

iTrader: (7)

I pulled that data sheet right off the GM Performance website. Sounds like they need to get their story straight...LOL

Andrew

gnx7

iTrader: (28)

What chassis is this going into? Why the need for a stock style computer/harness?

Considering Walbro 450lph pumps are used in high HP Nissan GTRs making 1200awhp+ why wouldn't they work on your car?

The GTRs actually have an issue with the fuel vapor locking so a factory Porsche fuel cooler (tapped into the a/c) is made to work and solves that problem.

dhutton

iTrader: (1)

As near as I can tell the LSA used in the CTS-V and ZL1 have moved to the higher pressure fuel systems within the last year or two. The LSA crate engines followed right along. The new LSA crate needs the higher fuel pressure with the injectors it ships with.

Don

dhutton

iTrader: (1)

It is going into a 69 Camaro. The stock computer and harness come "free" with the used engine and they would allow me to deliver the necessary fuel pressure with a properly engineered fuel pressure controller. I also want to run the Vapor Works tank which would take the stock CTS-V pump.

The Walbro pump will work as I stated above but a PWM controller is not readily available and I have heard they do not last long when used with PWM controller. Without PWM control I have concerns about fuel heating when sitting in traffic etc. The Porsche fuel cooler sounds intriguing but probably beyond my limited technical abilities... :>)

Thanks,
Don

kwhizz

Don......I have stock injectors in my car. The engine came out of a totaled (roll over) ZL1 camaro. I have the stock ZL1 pump in a Ricks Vaporworx tank with Carls control system Works perfectly with all the stock parts

Ken

dhutton

iTrader: (1)

Thanks Ken.

Don

kwhizz

The Vaporworx system is so easy to install is ridiculous...........Sensor in the fuel line at the tank and a module mounted near the Battery...........Sensor talks to the module and the module sends voltage to the pump to keep the pressure right where its set to be............Sensor, Module and a few wires Problem gone....

Ken

dhutton

iTrader: (1)

Carl has already confirmed that his system cannot support the requirements of the stock LSA controller. I read your thread and it seems that you had extensive dyno tuning done. I suspect part of this tuning was to compensate the difference between the fixed Vaporworks 60 psi versus the stock LSA tune boost referenced 65/87 psi. My goal is to avoid tuning and to use the stock controller as programmed.

I agree, the Vaporworks is a great product. It just can't support the specified LSA requirements without extensive tuning. This is also the reason that Spearworks supplies new injectors with their LSA setup, to allow fixed pressure without boost referencing. It would be interesting to see the duty cycle of the injectors in your tune at WOT Ken.

Thanks,
Don