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-   -   Intake madness. Teardown begins.... (https://rennlist.com/forums/964-forum/1078686-intake-madness-teardown-begins.html)

Goughary 07-07-2018 12:12 AM

That's what worked in the end. I'm thinking I need to go one size up on the tube and color the hose prior to install....

Goughary 07-07-2018 06:33 PM

14 Attachment(s)
Cleaning the intake manifolds today. And first pass at the throttle body.

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It's amazing how much gunk is in there. And the wild thing is how gritty it is- and how difficult it is to remove. When you see the "clean pics" below, they have been scrubbed first with wd40 to break it up, then dawn dishwashing liquid and then with my pressure washer. And they still are a little dirty...but clean enough to get to work on them.

Attachment 1285361

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Likelihood of these staying clean? Not much. But i have some ideas...coming soon if i decide to go through with it...but you know I'm completely winging this entire project and have no real plan...so where the wind blows...maybe it's a hawk, maybe a hand saw....i don't care cuz herons are equally as cool as hawks...

Attachment 1285365

Goughary 07-07-2018 06:47 PM

4 Attachment(s)
Now take a look at one of these manifolds...

Attachment 1285366

Attachment 1285367

Notice where all the crud is...this is telling you that you have blow by though the intake seals...

In this case, the seals are old and lots of crud has built up under them..

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Attachment 1285369

So if you want these things to function well, and you want no vacuum leaks, etc...it's not imperative...but a nice to have is to keep these clean and have a reasonably good seal (without having to crank down with huge pressure on the hose clamps.

Small bits of efficiency sometimes go a long way. All of us , for the most part, have cars that run. How many of us can say they run right? Or run at their best?

I drive a lot of 964's, and they ALL feel a little different from one to the other. It's crazy how much variation there is in stock motors...and really...it's this stuff that is making the difference..a little bit here and a little bit there. This microswitch clicking - that one not, this knock sensor works, that one doesn't. This vacuum Y Connector holds perfectly, that one, mostly...

Onward. It's been a long day. I have to go see Ant Man and the Wasp (my kid who used to ride in the booster seat in the back of the 964 is today all about Marvel movies....in four years, she's getting a 914 as a starter car...)

So - i have some thoughts and comments about the throttle body. They will have to wait till later.

Cliff hanger...

Goughary 07-07-2018 09:48 PM

6 Attachment(s)
Got to Ant Man and the Wasp...very early, and there were two seats left, and neither were together. So i just went out for ice cream, and ate enough to make my car noticeably slower.

Now i have to get rid of the oem carpet and buy an rs kit to compensate. Ugh.

First thoughts on the throttle body, and please chime in if you have any real knowledge here, cuz as much as i like to feel I'm the smartest person in every room I'm in...well...feelings aren't facts. And i am fully aware of that.

Attachment 1285377

So there are two plenums, they go to the same place. One isn't different than the other, and they work in tandem and at the same rate. The only difference in their movement is that the little one opens a couple millimeters first and then rest of its travel is one to one with the larger plenum.

Next up. Why the resonance flap (and the other plenum flaps) are not serviceable...

They are. But it would be silly to bother...

Attachment 1285380

So you'ld think you could just pull the e clip and slide out the shaft. On one side there is a clip, and the other there is the spring assembly and the arm is pressed and peened to the shaft.

Attachment 1285381

Attachment 1285382

So easy enough. Should just come apart.

But...

The flap is screwed to the shaft, which is smart right? Except that if the screws were to come out, your motor would be toast. Last thing anyone needs is to have a screw in the cylinder. Ka boom...ka chunk...and that's that.

So the boys at Porsche decided to screw the flap to the shaft, and then to press peen the back side of the screw, so under no circumstances is that screw coming out. Unless you dremel it. And then replace it, and then re-peen it.

Attachment 1285379

Attachment 1285378

So- therefore - is the resonance flap serviceable ? Yes. Maybe. I don't know what's in there for a bearing. But i am surmising that yes, if you really wanted to, you could service the thing. But with the effort it would take - not sure it would be worth it.

Should i take this one apart just so we can see? I can't . But if someone wants to donate me another aluminum matching throttle body, I'll gladly take it the extra mile. And even figure out a home shop remedy for the repeening of the screws...

Getting back to reality...

So here is the thing. We go through all this effort to make and retain vacuum pressure, and then you have these plenums that rotate on what is effectively a very loose fitting bearing....that leaks vacuum. So I'm thinking. One, maybe we don't need that much vacuum, so the pressure is high enough where the little leakage doesn't matter? Or two, figure out a way to press into that space, a highly viscous grease that will help retain the vacuum.

Next up will be further disassembly and more decisions to be made about how to refinish all these bits.

Peteinjp 07-07-2018 11:11 PM

The peening of the throttle plate screws is standard practice for many carbs such as the dual Weber’s that I had on my old bmw 2002’s as well as the bing carbs on my r90/6. Usually they can be removed with no damage to the throttle shaft as it is a harder material than the screw itself. A little work with the Dremel might put you more at ease in terms of the removal. People take these out all the time to replace throttle shaft o rings and bushings etc.

Re-peening can be done with a center punch or cold chisel as long as the throttle shaft is supported directly with with solid buck. Some choose to use loctite but I always used new screws and peened.

Pete

Goughary 07-07-2018 11:45 PM

Pete- just pm'd you back re the pedal box.

Thanks for the tip on the peening. I've been reading carb rebuild threads. So I'll have to figure this out. Most guys support the back side of the flap shaft and tap it with a pinch...

On this throttle body, you can't get to the back of the flap shafts on anything but the resonance valve and on that flap, the flap is on an angle to the body. So no way to easily support.

Porsche - judging by the indentation on the front side of the screw, uses a pinch plier somehow to press the peen into the back of the screw.

Regardless. I'm going to go ahead and remove them. I'm very curious about the bearing surface and I'm wondering if there is an o-ring in there. Which would be serendipitous cuz i found a shop with something like 50,000 o-rings in stock tonight. Was perusing their catalog for a little light reading...

Goughary 07-08-2018 12:25 AM

Reading a bit more- finding lots of guys needing m4x.75 Pan heads for throttle bodies- and they are not finding them. Wonder if ours are the same size. Guess I'll find out!

Peteinjp 07-08-2018 08:47 AM

Hopefully they come out clean and you can just reuse them.

pete

Goughary 07-08-2018 10:18 AM

One of the biggest problems with "reading" the interwebs as opposed to just looking at instapics and tapping heart icons...

Is that one finds himself reading comments like the following:

"Dude, make sure you get a set of JIS screw drivers, and not a crappy set. Otherwise you'll totally strip the MFI screwheads. There not like normal like screw heads cz there like japanese and they like don't make them like us"

So i start thinking as follows:

"Like, do the Germans like totally like make their own like version of the Philips like head that like I've known since my childhood to not be like the same from screw to screw cuz like they just aren't?"

So has anyone here read the Wikipedia page on screw heads?

https://en.m.wikipedia.org/wiki/List_of_screw_drives

My wife asked me something and i answered "wait, I'm reading about screw heads" - she rolled her eyes and walked away in wifely disappointment, but likely proud of how incredibly manly it is to even care about a screw type. ---we NEED this information---

Then my daughter asked me something, and i said "wait, I'm reading about screw heads"
And she responded "oh cool." ---but in a genuine and kind of interested way...
She's getting there...almost fully trained. I'll have her rebuilding a 912 motor by her 14th birthday...it's coming...i can feel it.

Anyway, read the screw head article. And as a base suggestion, if you have low quality screw drivers - particularly Phillips- toss the very low quality drivers, and put the mid quality in a drawer in the house to be used only on wood screws and super low torque applications.
In your garage, spend on screw drivers. Find a very good quality set and kept those around. When you knacker the head, replace it.

And if you need some advice for cost/quality of various brands- there are some great threads on garage journal. My default for high quality has always been snapon. But there are many others and some very good screw driver options from brands I've not heard of (but now own due to the tool box purchases I've made over the last few years)

And now i have to go downstairs and look closely at the heads of the screws in my throttle body and determine if i have anything that fits well enough to make the attempt to break them loose. I'm going on the assumption that since they are designed to be peened in place, that the metal used is very soft. And therefore, having been on there for 30 years, in all likelihood the initial torque to break them loose, could strip or destroy the head. So the proper size and type of screw driver head is important.

But dude like i don't like think like franz turned to fritz and said like ferry told us to like use like Japanese industrial standard like screws dude.

But maybe Butzi designed his own? Nah, doubtful. In 1991 butzi's company was too busy winning the Compasso d'Oro for the Jazz Lamp

https://www.studiofaporsche.com/en/w...ble-light-jazz

wallra 07-08-2018 10:21 AM

If you take those screws out make sure to scribe a line on the butter fly so when you reinstall you center the plate back where it is. also your throttle body you have right now on your motor is aluminum also with just one big butterfly for better flow and better volume.

jonathant 07-08-2018 02:59 PM

Resonance flap
 
Quick thoughts:

1) resonance flap butterfly disassembly - the 986 / 996 throttle body uses the same assembly. A little brief file work on the peened threads will enable unscrewing the plate-retention screws. Then use loctite to reassemble.

2) Hylomar HPF should work well for sealing the flap bearings: it’s a gasket dressing that is thick, sticky, stays put, and does not harden. Looks and feels like blue honey, but thicker.

3) don’t know why the two throttle plates but I would guess it has to do with giving a smooth part-throttle behavior just off idle. I stuffed a 3.4l motor into the old Boxster with a larger single-plate butterfly and the throttle tip in-out near idle is challenging. ‘Could be something else but that’s m’guess.


Originally Posted by Goughary (Post 15127495)
Got to Ant Man and the Wasp...very early, and there were two seats left, and neither were together. So i just went out for ice cream, and ate enough to make my car noticeably slower.

Now i have to get rid of the oem carpet and buy an rs kit to compensate. Ugh.

First thoughts on the throttle body, and please chime in if you have any real knowledge here, cuz as much as i like to feel I'm the smartest person in every room I'm in...well...feelings aren't facts. And i am fully aware of that.

Attachment 1285377

So there are two plenums, they go to the same place. One isn't different than the other, and they work in tandem and at the same rate. The only difference in their movement is that the little one opens a couple millimeters first and then rest of its travel is one to one with the larger plenum.

Next up. Why the resonance flap (and the other plenum flaps) are not serviceable...

They are. But it would be silly to bother...

Attachment 1285380

So you'ld think you could just pull the e clip and slide out the shaft. On one side there is a clip, and the other there is the spring assembly and the arm is pressed and peened to the shaft.

Attachment 1285381

Attachment 1285382

So easy enough. Should just come apart.

But...

The flap is screwed to the shaft, which is smart right? Except that if the screws were to come out, your motor would be toast. Last thing anyone needs is to have a screw in the cylinder. Ka boom...ka chunk...and that's that.

So the boys at Porsche decided to screw the flap to the shaft, and then to press peen the back side of the screw, so under no circumstances is that screw coming out. Unless you dremel it. And then replace it, and then re-peen it.

Attachment 1285379

Attachment 1285378

So- therefore - is the resonance flap serviceable ? Yes. Maybe. I don't know what's in there for a bearing. But i am surmising that yes, if you really wanted to, you could service the thing. But with the effort it would take - not sure it would be worth it.

Should i take this one apart just so we can see? I can't . But if someone wants to donate me another aluminum matching throttle body, I'll gladly take it the extra mile. And even figure out a home shop remedy for the repeening of the screws...

Getting back to reality...

So here is the thing. We go through all this effort to make and retain vacuum pressure, and then you have these plenums that rotate on what is effectively a very loose fitting bearing....that leaks vacuum. So I'm thinking. One, maybe we don't need that much vacuum, so the pressure is high enough where the little leakage doesn't matter? Or two, figure out a way to press into that space, a highly viscous grease that will help retain the vacuum.

Next up will be further disassembly and more decisions to be made about how to refinish all these bits.


jonathant 07-08-2018 03:15 PM

Screw drivers
 
Yes there are a bunch of subtle differences in drivers. Phillips drivers are designed to cam out of the screw if over torqued, wearing the driver but saving the screw.
Pozi-drive looks virtually identical but does not cam out. If the screw is soft the Pozi will let you get enough torque to shred the head, however usually (IMO) they work better than Phillips. I have a bunch of teeny JIS for electronic parts and I think they are also straight cut like Pozi drive.
Note that Phillips screws are straight cut, it’s just the driver that is not. A hardened Phillips driver is usually a bad idea (again just IMO) since it gives you the worst of both: designed to cam out, but hard enough to damage the screw head instead of the driver. Better to use a magnetic driver with replaceable normal/soft Phillips tips. That way a stuck screw will sacrifice the bit (cheap) and give notice that removal might take Pblaster and a straight cut driver



Originally Posted by Goughary (Post 15128107)
One of the biggest problems with "reading" the interwebs as opposed to just looking at instapics and tapping heart icons...

Is that one finds himself reading comments like the following:

"Dude, make sure you get a set of JIS screw drivers, and not a crappy set. Otherwise you'll totally strip the MFI screwheads. There not like normal like screw heads cz there like japanese and they like don't make them like us"

So i start thinking as follows:

"Like, do the Germans like totally like make their own like version of the Philips like head that like I've known since my childhood to not be like the same from screw to screw cuz like they just aren't?"

So has anyone here read the Wikipedia page on screw heads?

https://en.m.wikipedia.org/wiki/List_of_screw_drives

My wife asked me something and i answered "wait, I'm reading about screw heads" - she rolled her eyes and walked away in wifely disappointment, but likely proud of how incredibly manly it is to even care about a screw type. ---we NEED this information---

Then my daughter asked me something, and i said "wait, I'm reading about screw heads"
And she responded "oh cool." ---but in a genuine and kind of interested way...
She's getting there...almost fully trained. I'll have her rebuilding a 912 motor by her 14th birthday...it's coming...i can feel it.

Anyway, read the screw head article. And as a base suggestion, if you have low quality screw drivers - particularly Phillips- toss the very low quality drivers, and put the mid quality in a drawer in the house to be used only on wood screws and super low torque applications.
In your garage, spend on screw drivers. Find a very good quality set and kept those around. When you knacker the head, replace it.

And if you need some advice for cost/quality of various brands- there are some great threads on garage journal. My default for high quality has always been snapon. But there are many others and some very good screw driver options from brands I've not heard of (but now own due to the tool box purchases I've made over the last few years)

And now i have to go downstairs and look closely at the heads of the screws in my throttle body and determine if i have anything that fits well enough to make the attempt to break them loose. I'm going on the assumption that since they are designed to be peened in place, that the metal used is very soft. And therefore, having been on there for 30 years, in all likelihood the initial torque to break them loose, could strip or destroy the head. So the proper size and type of screw driver head is important.

But dude like i don't like think like franz turned to fritz and said like ferry told us to like use like Japanese industrial standard like screws dude.

But maybe Butzi designed his own? Nah, doubtful. In 1991 butzi's company was too busy winning the Compasso d'Oro for the Jazz Lamp

https://www.studiofaporsche.com/en/w...ble-light-jazz


Goughary 07-08-2018 03:56 PM

3 Attachment(s)
Yeah. I know the butterfly is bigger on the newer intake. I'm not convinced it's better. We will see.

I swapped out the manifold with the broken tab (back end holder for the air box). I had to make a little bracket to use temporarily until i have that piece welded at some point

Attachment 1285480

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That'll work for a while. The only thing it really does is keep the airbox from swinging around and pulling the afm out of the bellows...

Onward to cleaning mine- i broke out the really stinky stuff for this one. Wd40 and Dawn work well, but not as quick and east. The stinky stuff works immediately. But i am now stoned. So is that an upside or downside?...

Fwiw- i found the screw heads in the throttle body respond well to a PH2 Phillips. Though I'm not sure if that's the absolute correct driver. But, they broke loose easily. I have not removed them. That's for "next up" once i figure out how to organize my mess on the bench. I need to figure out how to stay methodical here. There is a lot to buy, a lot to salvage and a lot to explore. And not a huge amount of time or money. So there will be pauses ahead and after coming back from a pause is when you always have the "now where did this spring go?" "What's this screw for?"

Meatball964 07-08-2018 05:20 PM


Goughary 07-08-2018 05:30 PM

Amen.

It's funny...on 964 that are always worked on. You really only need a set of 1/4 inch drive metric six point sockets and some extensions, a ratchet and a little 1/4 drive breaker- for almost everything.

And then obviously for the big stuff, ok...but i find that with my car, i used to always go to the 3/8 or the 1/2 drawers. But now I'm almost always in the 1/4 drive drawer.


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