Reversed Intake Manifold/TB Thread

[wgknestrick]

After completing this mod and trying to find at least a little info about it, I'd like to help some fellow Nasioc'ers with what I've learned in the past month.

First, This mod is for advanced mechanics/DIYers only. You have to have a spare car to get around in as your Suby will be down for a considerable time. I have been chipping away at my car for about 1 month. You will have to make/fit your own IC tubing. This means cutting/welding of Aluminum to fit it up.

This is a great time to complete some other worthwhile mods too. PORT YOUR TGVs, Throttle body, Intake manifold, etc. If you take it off, no sense putting it back on un-ported. There are threads about these and I will not cover info about these DIY mods here.

I already had a Perrin FMIC, so I decided to convert that using the existing tubing and bends to help me with the new FMIC to TB tubing that would have to be made. I was able to do this without having to buy any other bends besides a Silicone 22deg that I had from the Perrin intake.

IN CASE YOU ARE WONDERING, I eliminated about 2.5ft of tubing by reversing the manifold. I just measured all of the pieces I had left over from the original tubing.


If you've done this mod, please post pics and any advice to help the community.

DISCONNECT YOUR NEGATIVE TERMINAL (I am a moron and forgot to when I started. Came back the next day and blew a main fuse messing around with the alternator)

Some helpful links of other reversed manifolds

http://forums.nasioc.com/forums/show...ntake+manifold

http://forums.nasioc.com/forums/show...ntake+manifold

http://forums.nasioc.com/forums/show...ntake+manifold

http://forums.nasioc.com/forums/showthread.php?t=775927

http://forums.nasioc.com/forums/show...ntake+manifold


I will break down the general steps into posts.

Bill

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[WRXskeet]

cool thread

[wgknestrick]

FIRST STEP:

(Remove the AC system)

I know that this may not be totally necessary, but it sure is helpful. I've only seen one person that was able to keep their AC and do this mod with the stock manifold.

You will be removing the AC compressor, lines, and condensor. This is necessary because you must move the alternator over to the space that the compressor is occupying to make room for IC tubing. Here is a in progress pic to show what I am talking about



This is very easy to do and I will not go into every step. You must evacuate the refridgerant first, (or accidentally like I did). . Radiator needs to be removed to get at the condensor in front of it. You will save about 10-15lbs by removing all of these items. Compressor is proabably 10lbs, so if you don't remove the condensor, no big deal, it hardly weighs anything.

Note how much room is left with no condensor or radiator. This would be perfect for a V-mount (which I highly recommend).

[wgknestrick]

STEP 2
(Mounting the Alternator)

Yes, this may be difficult, but I have some huge tips to save you big time "pondering" on how will you ever securely mount the AC in line with the belt.

You will notice that the compressor ran on its own belt system separate from the alternator and PS pump. Compressor belt uses a different # of peaks from the crank AND is on a differnt belt plane. This does not help us out in any way. What does help us out is that the alternator is easily "flipped" over to the compressor space and is on the same belt plane. It also can be adjusted on the same axis/bolts it was mounted onto the center bracket, just over on the other side. This does help us out.

Do not throw away the mounts used for the AC compressor. It just happens that they are perfect for the alternator WITH SOME MODIFICATIONS. My setup even allows you to adjust the alternator up and down to tension the belt as you will now need a way to do this.

First bracket to modify is the black sheet metal bracket by the oil fill tube. THIS IS THE RED ONE AROUND THE OIL FILL TUBE IN THE PIC. YOURS IS BLACK, MINE WAS POWDER COATED RED.

Use a saw and cut the mounting tabs (ones with holes) for the wire looms off as shown below. DO NOT THROW THESE AWAY. YOU WILL BE USING THE LARGEST 90deg tab for something. This will be bolted onto the end of the black sheet metal bracket to mount the tensioner bolt. You can acutally see this bolted onto the front of the large bracket as part of my tensioner assembly. (90 deg tab is RED and shown in 2 pics below). This black sheet metel bracket (large one RED in pic) may need to be bent towards the drivers side to clearance the alternator once mounted

[wgknestrick]

Belt Tensioner




This is just the parts from the original alternator tensioner adapted to the new setup. Notice the OEM threaded slide, and bolt. As the bolt is tightened, the alternator rotates up and down tensioning the belt. This gives you about 1-1.5" of belt adjustment. You can also see on the front of the 90deg RED adapter where I cut it from the black sheet metal bracket.

The smaller recessed end (Top part in pic) gets a 10mm hex size nut to attach it to the sheet metal bracket. I used some nuts (spacers or standoffs will work too) to bring the bottom of the tension in line with the top.

I really didn't think it would be this easy, but it was. All it took was a lot of thinking and planning to come up with this method, now I pass it on. Best part is, that you don't actually have to make a single new part to mount the alternator. You just modify existing ones.

[wgknestrick]

Cast OEM compressor bracket mods



This bracket requires quite a bit of grinding.

First, you need to cut off the original compressor mounting holes to allow the alternator to slide up and down to tension the belt. These are the threaded ear holes that stick out at the very top of the bracket.

Second, You need to clearance the back side of the brack to allow room for the STIs electronic TB when the manifold is reversed. The throttle loom/plug on the side of the TB will not clear unless this is done. This requires mucho grinding as about .25" is interfering with the plug. (Parially shown at top of pic)

Third, You need to cut the front surface where the idler pulley was mounted onto this bracket. This is to provide a solid mounting sulface to mount your new pulley to. The problem is that you need to cut it so that your new idler pulley is in the same plane as the rest of the pulleys. You will be going to a single belt system. I just redrilled and re tapped one of the existing holes to mount the new idler pulley.

You will need a Gates Micro V belt K050460 (5 peak, 46in long)
Length will depend on size of idler pulley. It is always a good idea to get about 3 sizes and take back what you don't need. I measured my belt track with a tailors tape with the tensioner adjusted to get the smallest belt size. Belts should be about this length due to the belts setling into the grooves and stretching. It may be difficult to get it on at first, but just get a socket and turn the alternator pulley to ease it on.

You will also need a .75" wide back side idler pulley. Make sure it is ball bearing and is rated upwards of 9K RPMs. Mine was found at

http://www.nhipulleys.com/catalogue/15967.html
ZFH-5212 3.25 .75 3.75 5 Flare .472 203 .669 1.00

I posed like I was needing one of these to "sample" for my Engineering project at work. They sent one to me for free to "sample". Normally they are about $12-$15. Idler pulleys are semi hard to find, especially BB ones. Problem is that this Co. has a min order of $100.

I tried McMaster Carr, but couldn't verify any BB pulleys to work. If you find one please post.

[wgknestrick]

STEP 3:
(Removing the Intake Manifold)

Consult the STI shop manual for detailed steps to do this. Be carefull disconnecting the fuel lines and clean up any fuel that is spilled.

MARK AND TAG EVERY VACUUM LINE AND WHERE IT GOES.

I did not do this, but boy do I wish I did. There is a rats nest of small tubing and it can be (IS) very confussing to re-assemble once the manifold is now rotated 180degs. It will probably take you at least a day to port everything on the manifold/TGV assembly, YOU WILL FORGET WHERE ALL THE LINES GO. Double and Tripple check your connections against the exploded intake manifold diagram from the shop manuals. You don't want to remove the manifold to fix a stupid mistake.

With the intake manifold removed, PORT THOSE TGVs and re-rout all of the vacuum lines to the fuel regulator, EGR, etc. The hard fuel line DO NOT GET ROTATED. Just remove them and re-rout the air lines to them. Make this as neat as you can and wire tie everything down. It is much easier to do this with it off of the car.

[wgknestrick]

STEP 4:
(Installing the Reversed Intake Manifold)

Use all new gaskets for the manifold/TGVs and the TGVs/heads. Once again, you do not want to remove this to fix a stupid mistake once it is on. I found it easier to completly assemble the manifold TGVs first, then carefully lower them onto the heads. This is a great time to have a buddy. Be extra careful that none of your new lines get pinched, come off, or are damaged when you lower the manifold down onto the heads.

You will probably have to remove the alternator to allow for room until it is bolted down.

ALL OF THE WIRES AND LOOMS WILL REACH. YOU SHOULD NOT CUT OR SPLICE ANYTHING IN THE HARNESSES. IF YOU ARE, SOMETHING IS WRONG (read the above line again if you are thinking about it)

Everything should fit and reach if done correctly. Just work on re-running the brake booster line (now on the front passenger side), the PCV lines, BOV line, etc. Make sure all of the connectors are plugged in. The cam sensor plugs are easily missed, so make sure you get them.

You will notice that the coolant resivour holes don't match up with the threaded standoffs on the (now passenger side) of the manifold. You will need to slot the back hole of the resivour to fit two bolts thru it.

I wish I had pics of this manifold off of the car. COMING SOON.

[wgknestrick]

I'm tired, more updates and pics to come.

Keep checking previous posts as I am always fixing mistakes, adding info, etc.

[Unabomber]

Nice write-up. You might consider doing a little copy/paste action over on scoobymods too.

[wgknestrick]

STEP 5:
(Planning Tubing Rout)

As I mentioned above, I have a Perrin FMIC. This has different sized tubing depending on what side you are dealing with (2" and 2.75" DIA). I realize that my rout is not the optimal, but I deemed it "Diminishing Returns" to change sides. I believe I am the only one stupid, pioneering, and/or ambitious, (take your pick) enough to run the return tubing on the passenger side to a reversed manifold.

Whatever path you take, make sure that:

A) you can close the hood.
B) you are not rubbing bare rubber hoses (vac lines, PS lines, etc) If it is in contact, put some loom around it or the protective nylon mesh.
C) You are actually saving some tubing length.
D) Your tubing is semi flexible and can move with the engine as it rotates on the mounts.

You will have to use a 45deg silcone fitting off of the TB to clear the hood with any kind of "sleep at night" confidence. The TB is angled upwards quite a bit when reversed and needs to be brought down quickly. Here is a pic from the side of the car showing a 2.75" 45deg coupler that has been cut to the length of the TB flange (this also lowers the tubing).



Overview of my routing:

[turbo2ner]

Any track times with that monster? Nice set-up! I don't see any NO2. When are you gunna play with that?

[turbo2ner]

What about the turbo coolant tank? (I don't have one now)

[tm999xxx]

very nice...we need more people like you on these boards...

[wgknestrick]

Coolant tank will come when I get it back from the powdercoated today. There will surely be a couple of updates.....And finished pics, and dynos.

[Evil STI]

What you have just done is the ONLY way I would ever use an FMIC, and I've been waiting for someone to work the bugs out. The only difference is that I would route the piping from the turbo to the inlet of the intercooler on the passenger side and return on the driver side. Good stuff!!

[subalou1]

looks sick, someone should come out with a kit. ^ i would route it that way too though, it seems you would save more pipe?

[Balr14]

Don't mean to seem like a n00b, but what purpose does this mod serve? Also, wouldn't it be more advantageous to go with an aftermarket intake manifold, instead? I'm not trying to be a wiseguy, I don't know that much and am always trying to learn.

[distorto]

the main point is to shorten the amount of pipe on your front mount, to get rid of any lag that is associated with the extra piping a front mount kit adds.

[turbo2ner]

Now, put your radiator where the TMIC was. I've seen that before. I use alky injection and no2. That pretty much cools the air about as cool as you can get it, without freezing something. I use a TMIC, but, to each his own.

[Alleggerita]

So I am curious about the one person that managed to keep their AC with the reversed manifold - I'd love to see what they did. That would be something a vendor should offer as a commercial kit, that is a reverse manifold set-up that allows to keep the AC.

[wgknestrick]

It was what I would call and "extreme" setup and I still think not for everyone. I just wish I could find it. It was a black STI with a custom FMIC that had the inlets coming out of the top of the FMIC. V mount style but a short and squatty core. I think he had to crush the tubing to clear the hood AND make manifold spacers to clear the alternator.

[Balr14]

Originally Posted by distorto

the main point is to shorten the amount of pipe on your front mount, to get rid of any lag that is associated with the extra piping a front mount kit adds.

Thank you. I guess that's something I don't need to worry about on an FXT. No room for an FMIC, anyway.

[wgknestrick]

Some pics of my setup now finished

Bill

[offset]

Looks awesome!! But why didn't you paint the oil cap, dip stick, and coolant cap like the rest of the stuff (actually I would just find some ricey sticker to recover the coolant cap)? What paint did you use for the rest?

TIA,
offset