FastKat

iTrader: (10)

I am doing an LS1 engine swap into a Jaguar. If I want to keep my LS1 engine's EVAP system/selenoid working properly, do I need to use the LS1 charcoal canister and fuel vapor accumulator?

FastKat

iTrader: (10)

TTT - How do I make this work properly? I want to use my Jag charcoal canister because it is part of the system that control fuel tank vapors and more importantly, releases air back into the fuel tank to replace the burnt fuel. Without this system, I will keep creating more and more vacuum in the fuel tank which is bound to cause problems.

I was thinking about taking out the EVAP assembly that sits on the intake manifold and running a line from my charcoal canister straight to the bung on the intake manifold, however this will allow unmetered air to enter the system.

Any thoughts?

69 Ghost

I don't know how the Jags are set up but personally if you can keep it I would. Most people do not realize that the ECM's OS has a lot of code built in to deal with it. As for the vacuum part the tank has a breather either through the cap or another vent tube with a one way valve. The tank is usually has a pressure valve of about 1 psi. A lot of conversions just put a filter on the end and let it breathe. I had that with the pressure valve inline and you could hear it release at times. On my LS conversion I am using the total system off the donar car.

FastKat

iTrader: (10)

It seems like the whole Jag system is going to vent the fuel tanks just fine, and that the charcoal canister will clean the vapors just fine, too.

The question is where to hook my charcoal canister into the engine. The Jag runs the line from the charcoal canister to the air box, BEFORE the MAF. The LS1 runs the canister to the intake manifold, AFTER the MAF.

It seems like I have a few reasonable alternatives:

1) Run the charcoal canister into the my air box. This will eliminate that whole EVAP assembly... not sure what the consequences are.

2) Run the charcoal canister directly into the intake manifold. This will bring unmetered air into the engine.

3) Run the charcoal canister into the EVAP system on the intake manifold. THIS is what I need more info on, to see if it would be reasonably easy.

4) Transfer over the LS1 charcoal canister, vapor accumulator, and who knows what else? Not really what I want to do - don't want to mess the the Jag's fuel tank vapor recovery and pressure relief system.

Any thoughts on 1 and 3?

rotoober

iTrader: (8)

#3 would require the LS1 purge valve, and the ability to get it to work right. I believe that the ecu needs info from the charcoal canister vent valve and some fuel level information for this to work right. Trying to get this to work right on my RX7 swap...

FastKat

iTrader: (10)

Okay, so if the ECU needs info from the charcoal canister and vent valve and the fuel tanks to make the EVAP purge valve work correctly, I think I am just going to forget about it and do #1 like on the original Jag setup.

I guess I will have to weld a bung onto my intake somewhere, and maybe get a one-way check valve that will close when the engine isn't running.

You are going to have a beast of a car when you're done!

69 Ghost

If you have the factory LS canister system why not use that? A sealed system will not hurt performance and like I said the third gen guys found that there is code to compensate for AFR when the system is purging the vapors. I would assume the same. For me I built a canister mount behind my back axle and then mounted it as a stock setup. It appears that the LS canister setup is a bit different and has a little breather box the size of a pack of cigarettes. The fuel pump assy has a hole for a pressure sensor in the tank. I could not use the pump/sender assy due to the hole size being to small in my tank but I was able to take the factory harness off and adapt it to my sending unit. I just teed the pressure sensor into the cannister system after that. I have a pic if you need it.

79dirt

Hi,I have read through your post several times and am having trouble understanding if I can make my purge solenoid work or what I should do with it. I have a ls2 and I finally got it running but don't know what I should do with the purge lines on the intake. I fabricated a ring that I welded into my stock gas tank that I dropped a 2000 camaro fuel pump assembly into the tank. I thought that the middle port out of the assembly was the vent so I hooked it to stock hardline that runs under car and up under brake booster. Could i hook this up somehow to purge line in back of motor? I basic don't know if it will hurt if I do away with the purge lines or if I could understand it I could try to make it work.????

LS1GMCTruck

iTrader: (2)

In reponse to FastKats original inquiry: The answer is no. You don't need any of the EVAP system at all, to allow the engine to run properly. Simply remove it all, and have the computer reflashed accordingly. There will be no issues with the fuel tank at all, simply make sure its vented properly.

79dirt

Thank you, I guess that is what I will do in my case since it will not affect the car running correctly.

bczee

iTrader: (12)

FastKat, a few thinks that I have learned or been told, the EVAP is controled by the PCM and it needs input from the Fuel Level and Pressure sensor. So, unless your going to also connect those up. the EVAP many not work even if it is connected.

What I did for my Chevelle was to leave the Chevelle system intact, Fuel tank line to the Charcoal Canister and ran the PVC/Vacuum port to the LS1 EVAP port (or where it used to be connected to on the left side of the intake). I have not had any problem of pressure inside the tank or vapors. It seem to work ok that way, I have also try to just plug the PVC port and just run Vacuum to just draw the vapors from the take and just let the vapor escape out the charcoal and filter bottom. that works too (current setup).