How To Install The GT350 Intake Manifold

so im currently in the middle of installing the GT350 IM. I'm having a lot of trouble at the back of the intake manifold where there are these two clips. so i call JDM. (you know, the guys who say they've got it down packed) well i get on the phone with them and they say you cant do it because you have to delete vacuum lines. well im very mechanically inclined but the clips are giving me some trouble. but they said to wait another week until their 80 dollar instruction kit is out. LOL i just paid 1200 and you cant help a guy out over the phone.. thanks guys.. so if anyone else has some info on how to replug the lines or hints and tips on how to unwire the two clips in the back that would be great. as for advice dont go with JDM. their over the phone help consists of.. wait a week and give us 80 dollars then wait another week for it to ship.. yeahh no thanks i just paid 1200..

So you ordered all this stuff from JDM and call to ask a few questions about the install and you get that answer?

Anyway, hope you get it figured out quickly!

yeah we got it worked out i talked to higgs and sandeale on the phone. they had already done the install and were amazing help. were going to be able to finish it up now. i owe them a lot! so shout out to higgs and sandeale!

ill have pictures and some better insight to add to the installation process for other people to come. as of right now were extending the wires that are behind the IM by cutting into the loov they are tied into. and pulling out more wire. its not as scary as it sounds for anyone who reads this in the future. the two clips under the stock IM in the back are by far the hardest part. they have a red sliding piece that needs to be pulled down in order for you to take them off. once they are off the IM will come out. once we get this part done we will be starting on vacuum lines and ill comment again to give more info on that.

Glad you got it sorted out Mike!

Thanks man but we hit a damn road block. MMR sent me the wrong throttle body adaptor. They sent me the TB adaptor for someone who has the stock intake manifold but wants the gt350 tb. So my car is dead in the water. I called terry at beefcake and he is going to talk to MMR on Monday and hopefully I'll have my part Tuesday.

I just got off the phone with terry from beef cake and he is going to have them ship me one asap. Terry is the man and if you guys do need help go to him. He's helped me in the past and he just came in huge for me today, even over the holiday weekend. So shout out to Terry

Nice , terry is a good guy for the community . Interested in your results when you get finished .

As for the installation here it goes.

Step 1. Take out your CAI or stock intake of you don't have one. Take out the sheild as well not just the piping and filter.

Step 2. Start to remove all hoses and connecting clamps. ( don't remove the two main hoses on top of the engine)!

Step 3. Remove your fuel rail clamp, put a towel underneath for the small amount of fuel that will come out.

Step 4. Remove fuel rail bolts and pull it out, don't take the injectors out of the fuel rail there is no need. Once done set it down somewhere upside down.

Step 5. Undo your stock throttle body and take it off. There will also be two other pieces on the stock intake manifold that will need to come off. They are at the front near the throttle body. One is on the top and one is just to the left angled to the side. Remove those and set them aside or put them in your gt350 IM.

Step 6. You're going to unclip the two blue clips in the back of the intake manifold one should have tap on the top and the other one won't it's just to the left side of the other one. After that go ahead and unbolt the intake manifold.

Note: the intake manifold bolts will not come out they will just be loose just like the ones you see on your GT350 IM.

Step 7. This is the hardest part...... Once those bolts are out you can lift your intake manifold off the valley of the motor. And underneath you'll see 2 white/yellowish connector clips. They have a red slip behind them that needs to be pulled down in order to clip them off. The hard part is getting that red slip to slip down. While you're down there you will see a black clip.. DONT FUCK WITH THE BLACK CLIP.. It's not relevant so just leave it. Once you unclip those two bottom clips you can take the stock intake manifold out.

Step 8. You have to extend the two wires that lead to the two blue clips you just took off of the top of the stock intake manifold. You can do this by cutting into the long thick bung they are leading into, cut towards the passenger side and pull the wire up. Don't worry it's not as scary as it sounds. But you will need quite a bit of wire, say 3-5 inches to be safe. After those are long enough to reach the new connecting points you can go ahead and put in the GT350 IM. See step 9.

Step 9. Clip the two bottom clips in first and slide up the red slips, then seat the intake manifold till it sits correctly, after that connect the two blue clips to the top of the IM. The one with tape should go to the top connector and the one with out should go to the one that is angled on the side.

Step 10. Bolt the IM In and put the fuel rail back on. You'll have to slide the left side of the fuel rail under one of the wires that's on top of the GT350 IM. And then it will go down into place. Make sure you clip the fuel rails in so they are snug. After that attach those two pieces you took off the other intake manifold that were close to the TB if you already haven't and put those in.

This is as far as I have gotten so far since my TB adaptor is wrong. I will edit this and finish it later in the week once my part comes in. I hope this helps

EDIT FOR FINAL STEPS! UPDATE!

Step 11. after all of this is done you can go ahead and install your TB.

Step 12. Now were going to talk about vacuum lines. This is your to get list from a local hardware store. 1 Foot of 3/8th's " silicone vacuum line. and 6 inches of 1/2" silicone vacuum line. and 1 90 Joint with a 1/2" side leading into a 3/8th's " side. that is your list of things to buy. on a side note.. i did buy the JDM evac extension for the top clip which is ontop of the intake manifold right next to the TB you can see what im talking about in the photo two comments down above the number 2 arrow.. you can extend the stock one but i just bought extension from JDM. (the one good thing they did for this project..) as for the hoses you are going to delete: take a look at the picture below again. and see the Number 5 arrow. see the hose he has? well youre going to just take out the original one. it will actually be two hoses. (im going to post a picture) that you will just permanently take out. and you will replace those hoses with the things i told you to get. see number 5 originally connected into your air intake but now it just cuts down at that 90 degree angle and connects straight into your brake booster. and Number 1 then connects into your air intake.

Step 13. well if you've reached this step following my instructions i feel pretty damn good about myself. I hope you've understood everything and if you have questions you can feel free to PM me. if you need over the phone help just ask for my number or leave me yours and ill be happy to call you and answer any questions you may have over the phone. even if you didnt buy anything from me.. :lol::cheers:

so i hope this helps and ill upload some pictures later. i honestly need some help on how to upload pictures to this site because i just dont know how to do it honestly.. lol laugh it up at me i know.. but if some one could help me out that would be cool

Thanks for saving people $80,

Yeah.. Paying 80 bucks for a piece of paper seems odd to me..

Everything is pretty self explanatory for the most part on the install until you get to those bottom clips and extending the two wires and the vacuum lines after you install the GT350 IM. But I've got that part figure out pretty well and I'll make it as easy as possible for others to understand

Sub'd

Screw over forum members. That's how you lose out on a lot of business.

Plumbing

Mikeiscoo2, nice write up. Sorry about the wrong adapter plate. I guess all good things are worth waiting for. ;)

This may help a little with the plumbing on the install. GT350 intake, throttle body, and an existing JLT CAI. Just finished up mine last Friday:

1. I replaced the GT350 hose and end connector off the tee with a piece of 3/8" silicone vacuum line. The GT350 piece is pre-formed and was putting the clip-on connection at the JLT air intake tube in a bind. Removed the straight fitting from JLT intake tube and loosely placed in a vise to press on hose, then re-inserted into the intake tube. Hose clamped tee fitting end - was a loose coupling.
2. Connected same as OEM manifold connection.
3. Purchased a 6mm x 31mm long threaded stud from Ace Hardware along with a 6mm flange nut to use on the driver's side to hold down the purge valve. The GT350 factory hold down will now slide onto the exposed threads. A 6mm x 30mm flanged bolt will do for the passenger's side. The ones from the OEM manifold won't work - they're self-threading. The GT350 manifold has inserts with M6 x 1.0mm threads.
4. Hose clamped tee fitting end that feeds the charge motion control valve diaphrams at the rear of the manifold - just to be sure.
5. 1/2" hose from manifold port to 1/2" x 3/8" reducing elbow. 3/8" silicone vacuum line to existing power brake booster hard line.

All vacuum connections at the rear of the manifold were left as shipped.

If any of you have the Performance Pack, pay no attention to the dash vacuum gauge. It will show a drop of about 4" vacuum at idle. This is probably due to the different manifold/throttle body. The gauge is electronic, and I believe it is being "fooled" by the new setup. Check for leaks and use a separate vacuum gauge right off the manifold tap. This is what I get off the manifold at idle:

I have had no problems with surging, hesitation, or tip-in. Put 600 miles on it since the install in traffic, on the freeway, and "down in Mexico". I'm running a JLT CAI with a 4" to 4" Vibrant 2718 silicone coupler to the GT350 TB. Tune is from Lund.

Can't stress enough about proper vacuum and checking for leaks. If that's what's actually happening... I don't think that it could ever be entirely tuned out.

Your mileage may vary. Void where prohibited by law.

That is all...