How to scale the HPFP pressure sensor

[djuosnteisn]

Under closer inspection this morning before coming to work, it looks like there is quite a bit of room between the bottom of the threaded valve, and the bottom of the threaded rail hole. There is a slight discoloration where it looks like the valve threads in only so far.

Now we may need a thicker restrictor disc to keep it from rattling around between rail face and valve face.

[Deadman]

if i had the pieces in hand i could have a disc turned down to the exact size (slip fit) and boom all done. measurements?! :p

[masskaos]

thicker = great idea.

it would suck to have the orifice bend or crack.

[Lex]

throw some putty on the spare rail and thread the valve in Dustin and see how much room you have to play with.

[djuosnteisn]

I'll bring my calipers home tonight and measure the depth of the rail and valve.

The rail side is concave, like a inward dome. You can kinda tell from the pics i posted above.

Putty is a great idea too. Kinda like a pseudo mold, lol.

Fuckin hate the double post merge, but oh well.

Here's the drawing:



You can see there is a 0.4395 to 0.5155 inch gap between the nozzle and end of the threaded bore.

Here's valve diameter:


And valve pitch:


If anyone wants to bump this post to notify people, feel free

[mkriebs]

I'll bump it, lol. Looks like progress is coming along well. I hope you all well, and I will continue to sneak behind the scenes and steal some ideas from your platforms. Us Cobalt Owners appreciate it!

[phantom3]

Originally Posted by djuosnteisn

When you measure threads, try to measure from one point on one thread, to the exact same point on the next.

\

In that picture it looks like you are measuring from the outside of the crests.

I've been looking at thread charts and I can't seem to find a M12 with that pitch. At least not a standard pitch.

There are:
M12x1.75 (Coarse)
M12x1.50 (Fine 1)
M12x1.25 (Fine 2)
M12x1.00 (Fine 3)

I think we are dealing with the M12 Fine#3 (M12x1.00). Which is unfortunate because it is the most uncommon M12 thread pitch. The common M12 is the coarse one (M12x1.75).

Also, after looking closely at the valve; The chamfer that was being discussed is just a lead-in for the thread.

[SpeedSixxx]

bump...dont take a dump...bump bump

[djuosnteisn]

Originally Posted by phantom3 When you measure threads, try to measure from one point on one thread, to the exact same point on the next. In that picture it looks like you are measuring from the outside of the crests. ....M12x1.00 (Fine 3) I think we are dealing with the M12 Fine#3 (M12x1.00). Which is unfortunate because it is the most uncommon M12 thread pitch. The common M12 is the coarse one (M12x1.75).

Haha, i was trying measure from a common point lol. Definitely looks like a 1mm pitch though, which is indeed unfortunate. I emailed macmaster carr inquiring where in the hell to find a threaded rod with those dimensions. If it really comes down to it, it may be possible to just get a local machine shop to turn out a few for us. There's one guy close to my work who could definitely do this, and probably for cheap (he's a motor head too ).

I like the idea of a threaded restrictor pill, cause it would hold the pill stead in the rail and keep it from rattling around or anything.

Wish i could find this domestically:
12mm 12 x 1.0 Metric Die M12 x 1mm Pitch on eBay (end time 03-Jan-10 08:19:29 GMT)

Wish and ye shall receive:
12mm 12 x 1.0 Metric Die M12 x 1mm Pitch - eBay (item 110465777875 end time Jan-03-10 00:19:29 PST)

[phantom3]

Lol... I just checked my tap & Die set... I actually have this die!

[socks]

Get some stock, thread it, cut it into proper thickness disks, and put like a flathead slot in it. and in the center of the disk, put the .060 hole.

[djuosnteisn]

Hell yeah, do it. Talk about an easy solution, lol, this is about as easy as it gets.

[phantom3]

I'll see what I can come up with. I just check my drill set and my 1/16 is snapped.

[djuosnteisn]

I might go buy a die set today. I took a half day cause i'm still feeling all f-d up.

[phantom3]

DJ, can you send me a schematic or how to for the ckt? I'll make one up and get Andrew to run it with his AP and the fuel restrictor.

[djuosnteisn]

Schematic is on the first page of this thread. Be sure to use an lm324 op amp.

Radio shack has everything you need to build it: op-amp, 10k linear pot (i used the lil blue one cause it fit nicely on the 0.1" center ckt board), several different flavors of through-hole circuit board you can use, and lil project boxes to put it in.

All the tap and die sets i see around here locally don't have that m12 x 1mm size. You must have a super set (which you prob do, lol). Any way you could built me up a restrictor? I'll happily paypal cost for materials + time + shipping .

[m4tic]

so am i trading for an evo or getting an ap for xmas :p

looks like good progress, this is exciting

[SilverDemon]

M12x1 set screws, they come in all lengths, just drill what ever size hole you need in the center. If you have ever tried to thread round stock with out a lathe it is almost impossible to get the threads straight. In order to hold the set screw in place while the hole is drilled, thread two set screws into a nut, tighten them against each other, clamp it into a drill press and drill two at a time.

Edit: Scratch that, I thought metric set screws would come in the 1.0 thread, but I can not find them. Still might be better off starting with a bolt and modifying it to do want you want, instead of trying to thread round stock.

[djuosnteisn]

Even the bolts are hard as hell to find.

[SilverDemon]

How many you need/want?

[Deadman]

try Home | Fastenal or http://www.memartin.net/

both companies we deal with through work.

EDIT:
dj im going to have this turned @ work on monday. I need to know how long it has to be ie.
| < insert inches > | i will pop a 1/16 hole in the center and send it to ya. If you get it done by then just lmk, and if not i don't think it will be a problem

[JmkC]

Originally Posted by phantom3 DJ, can you send me a schematic or how to for the ckt? I'll make one up and get Andrew to run it with his AP and the fuel restrictor.

haha i like how you just volunteer him

[superskaterxes]

Originally Posted by Deadman try Home | Fastenal or Untitled Document both companies we deal with through work. EDIT: dj im going to have this turned @ work on monday. I need to know how long it has to be ie. | < insert inches > | i will pop a 1/16 hole in the center and send it to ya. If you get it done by then just lmk, and if not i don't think it will be a problem

andrew were going to work TOMM and getting this shit done haha we can install same day

[djuosnteisn]

Originally Posted by Deadman try Home | Fastenal or Untitled Document both companies we deal with through work. EDIT: dj im going to have this turned @ work on monday. I need to know how long it has to be ie. | < insert inches > | i will pop a 1/16 hole in the center and send it to ya. If you get it done by then just lmk, and if not i don't think it will be a problem

Hell yeah! The gap between the end of the valve and the beginning of the angled portion of the bore is about 0.4395", but there is no need to make it exact imo. I say make it like 3/8" long or so.

Also if you want to make a handful or so, i think alot of people would be happy!!!

PM me your paypal so i can pay for the time+material+shipping and huge thanks man!


Also, like Sean said, it'd be rad if you could slot one end of it so we can thread it in with a screw driver or something.

[mkriebs]

You guys are doing amazing work with little resources! Way to step up guys. I wish the Cobalt community was more like this!

You almost have me considering a MSP6, lol.

[tmtbiker]

Originally Posted by mkriebs You guys are doing amazing work with little resources! Way to step up guys. I wish the Cobalt community was more like this! You almost have me considering a MSP6, lol.

These guys are doing amazing work, no doubt about it. You have no idea what the community has been through to get to this point, though.

As 'loosh would say.."if you only knew...."

[Haltech]

Originally Posted by tmtbiker These guys are doing amazing work, no doubt about it. You have no idea what the community has been through to get to this point, though. As 'loosh would say.."if you only knew...."

Fuck that cocksucker...

[Deadman]

ya ill put a slot in it for a flathead. Ill have them made 3/8" long (ill make one about .01 - .02 under the length you measured)

Ill have him part out as many as he can off the piece of stock we use. DJ anything in particular ie. bronze, aluminum, steel.. hot roll? cold roll? ha lmk

[djuosnteisn]

Well it'll be exposed to gas at a very high pressure (and prob fairly high temp), so it needs be pretty corrosive resistant.

I guess the fuel rail is made of aluminum, and the valve is bronze... Hmmm, i may not be the right person to ask about this lol. I say bronze cause it looks cool .

[SilverDemon]

Do not make it out of similar metals, the threads will lock together. Make them out of non-corrosive dis-similar metals, for example brass, or 300 series stainless.

This is how I went about making the part. A stainless M8 SHCS has a head that measures just about 12 mm on the dot, I chucked it into the lathe and cut the threads on the head of the bolt, since it already has a hex in the end I can skip the step cutting a slot for a screwdriver. After I cut the threads I drilled the .060" port through the head, then parted off the head of the bolt. The finished restrictor measures .290"

[socks]

rock on! hole is a lil big eh?

[SilverDemon]

It's between .060 - .070"

[djuosnteisn]

How many can you make? Thanks for that tip!

Between you and dead man, i think we'll be able to at least satisfy the need for all the beta testers .

[SpeedSixxx]

Originally Posted by djuosnteisn How many can you make? Thanks for that tip! Between you and dead man, i think we'll be able to at least satisfy the need for all the beta testers .

this guy corbs is interested in using it if you or anyone else can make another..

he has speed 3...intake, tip, tbe, cobb ap, ptp hpfp and other mods...

he is interested in it and is prolly willing to install and dyno tune with atr.

i sent him the link to this and he will be reading over everything.

[SilverDemon]

Originally Posted by djuosnteisn How many can you make? Thanks for that tip! Between you and dead man, i think we'll be able to at least satisfy the need for all the beta testers .

I asked yesterday how many was needed or wanted, but no one responded (I do not think I ever saw or at least remember how many people received the beta circuit). I generally do not get time on the machines until the weekend, so it will be at least another week (if I get to work on the weekend) until I can make any more.

[spnkr21]

If someone wants to send me a restrictor I'll take one. I'm running standback so won't need the djckt. Lemme know! Cost?

[SSinstaller]

My results will be pretty useless for you guys, but I'll take a restrictor as well....

[djuosnteisn]

Originally Posted by SilverDemon I asked yesterday how many was needed or wanted, but no one responded (I do not think I ever saw or at least remember how many people received the beta circuit). I generally do not get time on the machines until the weekend, so it will be at least another week (if I get to work on the weekend) until I can make any more.

LOL, sorry man if you felt ignored, this thread has been moving along quite fast. I sent out 5 ckt's total, including myself that's 6. I think deadman will prob make a few as well, but honestly i think the more the merrier, cause AFAIK, they are just as needed for the SB guys as they are for us djckt guys.

I wouldn't make more than 10 though honestly. Who knows if the hole size needs to change yet. It's still alot of speculation that 60-70 thousandths will be small enough. We'll see.

Originally Posted by SSinstaller My results will be pretty useless for you guys, but I'll take a restrictor as well....

I don't think any of these results are worthless. The basic principle behind both methods is the same, simply increased rail pressure, and how far it will take us. Just keep us posted with your findings!

[SilverDemon]

Originally Posted by djuosnteisn LOL, sorry man if you felt ignored, this thread has been moving along quite fast. I sent out 5 ckt's total, including myself that's 6. I think deadman will prob make a few as well, but honestly i think the more the merrier, cause AFAIK, they are just as needed for the SB guys as they are for us djckt guys. I wouldn't make more than 10 though honestly. Who knows if the hole size needs to change yet. It's still alot of speculation that 60-70 thousandths will be small enough. We'll see.

No Worries!! I will wait and see what size will work the best before I make a batch of them. One thing I would like to see is a thread pitch gauge on the sensor just to make sure this is the right pitch. Last thing I want is to get one of these cross threaded in the fuel rail.

[m4tic]

this thread has not been updated in 2 days wtfwtfwtfwtfwtf