GT350 Intake Manifold Install Observations

[defector]

Finished install of the GT350 intake manifold yesterday. I created a new post as the current posts are way too long to read through and wanted feedback specifically on the items I mention.

1) Like most things, doing this twice would take 1/2 the time.

2) I can't believe Ford Performance is selling these without instructions.

3) You have to be nuts to not buy the JDM evap harness extension (there is no place to 'take out' wire from). I have mine installed taut right now but plan to buy the $29.99 extension immediately. I think another solution would be a mechanical adapter to rotate the valve slightly but I've ordered the harness.

4) The information out there on the vacuum harness connections seems to be the most lacking.

5) Key things I'd share with others that I didn't see in other videos yet.

a) You must 'take out' wire for the purge solenoids from the rear engine harness. You will take this wire out from drivers side to passenger side and will need to take out about 3-4"s to avoid strain in these wires.

b) I believe some are misunderstanding how to connect the aspirator after I just saw this video. This video shows that the air induction system is connected to the VACUUM side of the intake. Not sure how this will run - maybe it gets by - but this is incorrect.
[ame="[MEDIA=youtube]z5a8wtkhZqY[/MEDIA]"][/ame]

c) How does the aspirator work? See the attached image from a Ford supplier's website. I think once you see this, you will understand how the routing must be connected, even if you must make your own.

d) From what a Ford engineer told me. The vacuum aspirator between the GT350 and GT are different. The GT350 makes more vacuum at low vaccum (WOT) and less vacuum at high vacuum (idle). I might switch back to the GT aspirator someday but for now kept the GT350 in there.

e) I have read some posts where people are saying, if you only show 17" of vacuum you have a vacuum leak. I don't believe this is true. After I installed the intake, I had 20" of vacuum strong before installing the Lund tune. After I flashed the Lund tune, it dropped to 17". Is that the whole story? I have no idea, but would like to see if others can share your findings here.

f) I see people putting the coolant hose plastic trays on top of the coolant hoses now, trapping them in place. That seems creative and OK, but I noted that my driver's side 'tray' is not straight and has a little kink to it, unlike some of yours.

Have not driven the car yet. Looking forward to that drive.

Jim

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[Terminator2]

Un clip the wiring harness and zip tie it to the metal part of the heater hose tube that will give plenty of slack. Route the pcv tube under the harness that will also help as it gets out of the way.

 

[ddozier]

4) The information out there on the vacuum harness connections seems to be the most lacking.

b) I believe some are misunderstanding how to connect the aspirator.

c) How does the aspirator work? See the attached image from a Ford supplier's website. I think once you see this, you will understand how the routing must be connected, even if you must make your own.

Jim

I just finished my install over the weekend and I agree after looking at the vac system most of the pics of installs I have seen including the one you have pictured in your post do not appear to be connected correctly.

In the picture the brake booster line is connected to the 2nd vac takeoff from the manifold and does not look to be connected to the aspirator. I have mine connected to the aspirator by removing the vac cap from the aspirator as it was shipped capped from FP. I capped the 2nd vac port from the GT350 manifold on the drivers side as the GT manifold only had one port.

Another thing that is different on the GT350 manifold is that the vac source for the IMRC system is connected to the back of the manifold and is routed internally to a port on the front of the manifold. The front port is then connected to one of the aspirators vac side ports, this is the same routing that the GT uses except that the GT manifold has an external line that makes the connection not an internal one like the GT350 manifold. This I believe is one of the sources of the confusion as it appears at first glance that the GT has an additional vac device that the GT350 does not, but in reality they are the same just routed differently.

I also separated the two vac lines that "T" together, one is a return from the IMRC and the other is from the aspirator. I used straight vac couplers to connect these two lines to the two lines that went to the CAI ports on either side of the CAI tube just in front of the throttle body. I reused the two hoses from the GT intake to make these connections. You can leave them "T" connected and plug the passenger side port in the CAI but this seems to be a better option as all available ports will have a hose connected to it except the one extra port that the GT350 manifold has that the GT does not. I have 20lbs of Vac after the car reaches its warm idle and the brake pedal has been pressed a couple of times to purge the brake booster.

I believe this is the correct method to connect these vac lines and will help to prevent the brake booster from loosing vac under WOT conditions.

If anyone has any input to my vac system connections I would welcome it as I have not had a chance to drive the car yet but the start, idle, and brakes seem to be as stock.

Dave

 

[wildcatgoal]

Interesting stuff here gents.

 

[Chameleon]

Excellent info Jim!

 

[Terminator2]

Good info I'll likely use my stock Aspirator and hoses wherever possible.

 

[09jsw]

THis is how mine is set.

 

[ddozier]

Right now your brake booster feed is not going through the aspirator, I am not 100% sure but connecting the brake booster to a direct vacuum port like you have it is not the way the aspirator is designed to work.

This is the way I believe your connections should go, and is how I did mine. I do not have any pictures of mine yet so I marked up yours.

Dave

 

[09jsw]

Right now your brake booster feed is not going through the aspirator, I am not 100% sure but connecting the brake booster to a direct vacuum port like you have it is not the way the aspirator is designed to work.

This is the way I believe your connections should go, and is how I did mine. I do not have any pictures of mine yet so I marked up yours.

Dave

Thanks Dave I'll give it a shot

 

[ddozier]

The Evap wire harness should be extended so you can put the passenger side wire harness back near the valve cover, the heater hose on the passenger side is going to melt that harness if it is touching, looks like it is in the picture.

Dave

 

[09jsw]

The Evap wire harness should be extended so you can put the passenger side wire harness back near the valve cover, the heater hose on the passenger side is going to melt that harness if it is touching, looks like it is in the picture.

Dave

Plan on ordering it today. I have it pulled off that hose now. That's an old photo.
Thanks.
Will I need to change the imrc line from the T connection if I don't want to run that second line on the cold air? I may just keep it blocked off if the imrc can function correctly at the T and only change the line for the booster.

 

[ddozier]

Plan on ordering it today. I have it pulled off that hose now. That's an old photo.
Thanks.
Will I need to change the imrc line from the T connection if I don't want to run that second line on the cold air? I may just keep it blocked off if the imrc can function correctly at the T and only change the line for the booster.

The two ports on the cold air are one and the same so having them "T" together is perfectly fine and will function the same, I just removed the T and reconnected the return from the IMRC so every port on the cold air intake tube would be filled with a hose and would not have to find a plug to fit the one on the passenger side if it was not used.

Dave

 

[09jsw]

The two ports on the cold air are one and the same so having them "T" together is perfectly fine and will function the same, I just removed the T and reconnected the return from the IMRC so every port on the cold air intake tube would be filled with a hose and would not have to find a plug to fit the one on the passenger side if it was not used.

Dave

Gotcha. Thanks for all the help.

 

[Terminator2]

Right now your brake booster feed is not going through the aspirator, I am not 100% sure but connecting the brake booster to a direct vacuum port like you have it is not the way the aspirator is designed to work.

This is the way I believe your connections should go, and is how I did mine. I do not have any pictures of mine yet so I marked up yours.

Dave

You could just keep the T there and just plug the lower port on the CAI?

 

[09jsw]

You could just keep the T there and just plug the lower port on the CAI?

That's how mine has been.

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