GT350/LU47 install

[CEHollier]

My son and I installed GT350 manifolds and LU47 injectors on our 15 GT's. The second car went much faster. We each used the JDM kits which helped with parts a lot. Everything fit. I drove a couple of miles to make sure everything was good so nothing to report performance wise. Going to do datalogs and let Lund dial it in. So far so good.

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[Bluemustang]

Notice it's much faster now?

 

[CEHollier]

Notice it's much faster now?

Yes. Above 5000 rpm I really feel the difference. Very strong up top. Didn't lose anything on the low end either. Drivability is good in stop/go traffic. I went with the stock TB. No surging. Well pleased.

 

[Saywhen]

Sounds like a nice setup. Lund has the tuning down pat on these and the CJ mani IMO

 

[CEHollier]

Sounds like a nice setup. Lund has the tuning down pat on these and the CJ mani IMO

John Nardi made it clear they could not guarantee no problems with surging with the 350 TB so I stayed stock. Well pleased.

 

[Saywhen]

That was a smart move on your part I think

 

[Mustang_Lou]

I was looking out for your post on the install. Nice. Any tips on problems encountered?

Would've been nice to do 1 car first and then both of you run each other to see if the GT350 mani car pulled away.

 

[CEHollier]

I was looking out for your post on the install. Nice. Any tips on problems encountered?

Would've been nice to do 1 car first and then both of you run each other to see if the GT350 mani car pulled away.

Installs were pretty much straight forward. We used the JDM install kit which is set up for the 350TB. We used the stock TB's so had to research a little to make it work. What is nice is stock vacuum hoses no longer needed can be modified and work nicely to complete the swap. We did datalogs today and emailed Lund. So we should be dialed in pretty soon. Out the box it runs well. I would imagine the initial tune is conservative to prevent knock. One tip make sure your torque wrench is in inch/lbs.

 

[Mustang_Lou]

Thanks. So you can easily reverse if you wanted to? (1 of my mod rules)

 

[CEHollier]

Thanks. So you can easily reverse if you wanted to? (1 of my mod rules)

Depends on your definition of the word "easily". Can be reversed.

 

[Mustang_Lou]

I look forward to more of your impressions Charles, especially the part throttle day-to-day difference where most of our driving would be.

 

[Taneras]

I was looking out for your post on the install. Nice. Any tips on problems encountered?

I'm CEHollier's son, we both did the same installs this weekend.

1.) Save all the tubing and clamps, even if the instructions or guide tell you that you no longer need that piece. We had to fabricate some of our own tubes to get things to fit nice and snug (like the break boost vacuum line).

2.) Make sure you have a tq wrench that you can set to inch pounds, when you move to install the GT350 manifold and whichever throttle body you end up deciding you're going to need one. The final values were 106 and 89 depending on the bolt, but if you can get one that goes lower (like to 40-60) for the sets of 4 and 6 bolts we tightened them up all half way then went to factory spec.

3.) Get some aerosol silicon lubricant to reinstall the hoses. We went with the JDM GT350 manifold/TB kit and even though we didn't use the GT350 TB the kit was still super helpful. The provided degas hose was pretty tight, and a little bit of lubricant goes a long way with reinstalling most of these hoses.

4.) It might be a bit confusing on how to rehook everything back up once the install is done. We mostly used Late Model Restoration's video and Mustang Lifestyle's video on YouTube throughout the install but especially at the end to make sure we had everything line up correctly. Late Model's install used the GT350 TB and Mustang Lifestyle's video used the stock, so keep that in mind when watching.

5.) Have a second pair of hands, removing the IMRC connectors behind/under the stock manifold, and likewise reconnecting them on the GT350 manifold is a pain.

6.) Save the black rubber plug that comes on the GT350 manifold. We used it to cover up one of the unused lines on the stock throttle body. It's a really tight fit, but with the aforementioned lubricant you should be able to get it on. Just be careful not to drop it, I got some lube on the outside and when I pressed to try and get it to seal it almost fell out of my hands.

7.) Unless you want a lot of gas in the fuel rails and a fair bit spilling I'd follow Late Model's opening step of disconnecting the fuel pump driver module connection and letting the car run till it stalls (using up most all of the fuel). We didn't on either car and ended up with quite a bit of gasoline spilling during the removal process and while installing the LU47lb injectors.

8.) Inspect your cylinder heads after you remove the stock manifold. My father had some pretty hard sandish material, one was a very hard rock, right on the edge of the seal. He actually got a little bit that we had to vacuum out that the valves caught before going into the cylinders. I on the other hand had some coolant split that was close enough to the openings to cause concern. Speaking of, let the car cool down for a few hours and open up the coolant tank. You'll depressurize the line and spill less.

Can't think of anything else. But if you have any specific questions I'm sure CEHollier or I could help out.

 

[CEHollier]

I'm CEHollier's son, we both did the same installs this weekend.

1.) Save all the tubing and clamps, even if the instructions or guide tell you that you no longer need that piece. We had to fabricate some of our own tubes to get things to fit nice and snug (like the break boost vacuum line).

2.) Make sure you have a tq wrench that you can set to inch pounds, when you move to install the GT350 manifold and whichever throttle body you end up deciding you're going to need one. The final values were 106 and 89 depending on the bolt, but if you can get one that goes lower (like to 40-60) for the sets of 4 and 6 bolts we tightened them up all half way then went to factory spec.

3.) Get some aerosol silicon lubricant to reinstall the hoses. We went with the JDM GT350 manifold/TB kit and even though we didn't use the GT350 TB the kit was still super helpful. The provided degas hose was pretty tight, and a little bit of lubricant goes a long way with reinstalling most of these hoses.

4.) It might be a bit confusing on how to rehook everything back up once the install is done. We mostly used Late Model Restoration's video and Mustang Lifestyle's video on YouTube throughout the install but especially at the end to make sure we had everything line up correctly. Late Model's install used the GT350 TB and Mustang Lifestyle's video used the stock, so keep that in mind when watching.

5.) Have a second pair of hands, removing the IMRC connectors behind/under the stock manifold, and likewise reconnecting them on the GT350 manifold is a pain.

6.) Save the black rubber plug that comes on the GT350 manifold. We used it to cover up one of the unused lines on the stock throttle body. It's a really tight fit, but with the aforementioned lubricant you should be able to get it on. Just be careful not to drop it, I got some lube on the outside and when I pressed to try and get it to seal it almost fell out of my hands.

7.) Unless you want a lot of gas in the fuel rails and a fair bit spilling I'd follow Late Model's opening step of disconnecting the fuel pump driver module connection and letting the car run till it stalls (using up most all of the fuel). We didn't on either car and ended up with quite a bit of gasoline spilling during the removal process and while installing the LU47lb injectors.

8.) Inspect your cylinder heads after you remove the stock manifold. My father had some pretty hard sandish material, one was a very hard rock, right on the edge of the seal. He actually got a little bit that we had to vacuum out that the valves caught before going into the cylinders. I on the other hand had some coolant split that was close enough to the openings to cause concern. Speaking of, let the car cool down for a few hours and open up the coolant tank. You'll depressurize the line and spill less.

Can't think of anything else. But if you have any specific questions I'm sure CEHollier or I could help out.

Ditto on the silicone lube. Using JDM's instructions you reverse the brake booster line. This requires removing two hoses connected to the metal tube that bolts to the manifold top. We had to clamp the metal tube to the table to pull the hoses off. Save yourself time and grief and cut the front hose off. We didn't use ours. We used the hoses off of the stock aspirator to route the line from the metal brake booster line to the 350 aspirator. Save the aspirator plug you remove to do this you will need it. Right behind the throttle body on the manifold around 2 o'clock in my picture you can see the plug. The JDM kit/instructions were helpful. They were pricy but we didn't have to hunt parts and the instructions gave good guidance. One thing they could do to make the kit better is tell people how to release the connections. Some were a PITA.

 

[djpheer]

nice. although i did my vacuum lines different from you. mine were done as shown in this PP3 document as shown on page 28. I am not sure why JDM says to reverse the lines:

https://performanceparts.ford.com/download/instructionsheets/FordInstShtM-9452-M8.pdf

 

[Taneras]

nice. although i did my vacuum lines different from you. mine were done as shown in this PP3 document as shown on page 28. I am not sure why JDM says to reverse the lines:

https://performanceparts.ford.com/download/instructionsheets/FordInstShtM-9452-M8.pdf

We ignored parts of the JDM instruction guide as it was for a GT350 manifold and throttle body install. We kept the stock throttle body so it will be hooked up differently. Same goes for the PP3, it uses the GT350 throttle body.

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