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DIY Turbo Discussion greddy on a 1.8? homebrew kit?

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Old 09-06-2006, 08:51 PM   #21
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F-that... I'm not doing it after this discussion, I'm just the visionary who thought it up. I'm gonna tap the pan Braineak-style and use a whole tube of JB weld on it. Get Rican to try it, he'll try anything.
I didn't come up with the idea. I just posted a picture!
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Old 09-06-2006, 09:49 PM   #22
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Mechazawa, if that's true, then it clears a lot of things up. I've never seen the discharge, has anybody?
Oh well, I'll let y'all know if I have any more brain-benders this week. I think it was worth the discussion if nothing else.
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Old 09-07-2006, 01:30 AM   #23
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Some of Greddy's turbo kits for other platforms drain the oil back into a fitting that replaces the drain plug. Not ideal but apparently it works just fine.
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Old 09-07-2006, 08:20 AM   #24
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Isn't the oil coming out of a turbo is frothy, displacing more volume then before passing through (the return line is larger then the feed line for a reason?)...
WOT has pointed out greddy has oil returns to the drain plug, there must be some length to them to allow the oil to cool down? (and maybe essentially) defroth (Maybe like a latte/ cappacciono--warm and cold) Could a short direct return line might not work out so well, as one that is too long might entice vapor locking?
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Old 09-09-2006, 01:21 PM   #25
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Some pics of the drain setup on my car.

I'm using one of the Function7 billet drain flanges, plumbed as follows:

Turbo -> drain flange -> 3/8NPT to -8AN nipple -> -8 straight hose end -> -8 hose -> -8 90* hose end -> -8AN to 3/8NPT nipple -> pan w/ JB weld.

You'll note how the hose is sort of formed to fit in a curvy way. I did this by making it slightly over-long, and when attaching the last fitting (the -8 straight end to the turbo side) I pre-tensioned the whole thing in this twist by holding a wrench on the red part of the fitting while I tightened down the blue part. It clears the coolant and steering lines nicely, and isn't really free to flop around on its own.

Specifically, this is the drain flange I have: http://tinyurl.com/n7rzg
I had to use different bolts, but apart from that it fits perfectly.
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Oil Drain Revelation and Fuel Pressure Gauge Setup-drain_1.jpg   Oil Drain Revelation and Fuel Pressure Gauge Setup-drain_2.jpg   Oil Drain Revelation and Fuel Pressure Gauge Setup-drain_3.jpg   Oil Drain Revelation and Fuel Pressure Gauge Setup-drain_4.jpg  
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Old 09-09-2006, 02:23 PM   #26
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pretty.
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Old 09-09-2006, 08:34 PM   #27
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Joe Prez

That tony turbo DP really looks good in those pics!!!
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Old 09-09-2006, 10:32 PM   #28
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Few comments on both ideas. Give up on both of them. The oil return needs to be at the highest point possible at the shallow end of the pan. 2" from top lip to center of tap works. That will clear the windage tray and make it shallow enough not to hit the oil feed line.

$20 will get you a 100 PSI electronic oil pressure gauge for safely mounting inside the cockpit. Electronic sendor does not care if it reads oil or fuel pressure and works just fine for reading fuel pressure. Try either JC Whitney or about any auto parts store. Just need to attach a grounding wire to the sensor when used as a fuel pressure gauge. Why would you need to read more than 100 PSI of fuel pressure?
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Old 09-10-2006, 12:29 AM   #29
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AM I the only one who notices that the guage is on the fpr and bieng there it will measure the return pressure. And not the feed pressure wich means it is useless the way he has it. Or am i wrong? As for tapping the pan if you have a 90 degree anlge air die grinder and a bit to go in it you can tap where i did just forward of the motor mount it doesnt get any more straight down than that tapping it was a bitch though took quite afew jbweld trys to get it in place and not leaking.
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Old 09-10-2006, 02:57 AM   #30
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LOL, good eye! I missed that. Not familiar with that AFPR, but if it is between the AFPR and stock FPR will only read what the AFPR is clamping and not the pressure in the fuel rail. If on the return side will only read pressure in the fuel tank which will always show zero or so small it will not read on a pressure gauge. In either event is completely worthless.
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Old 09-10-2006, 01:00 PM   #31
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Quote:
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Joe Prez

That tony turbo DP really looks good in those pics!!!
I was thinking the same thing. Looks very nice! No A/C helps give you room for that drain line too
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Old 09-10-2006, 03:18 PM   #32
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I was under the impression that the AFPR only operates when in a boost situation. With the Walbro 190hp, the stock FPR should be "open" all the time, flowing a ton of fuel back through the return. The gauge IS mounted on the "in" side of the unit, between the unit and the rail, allowing me to measure pressure in the rail... isn't that the idea??? Or should the gauge be mounted on the rail itself... How about on the inlet for the second feed I'll fabricate? Isn't it the same? Am I missing something?
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Old 09-10-2006, 06:42 PM   #33
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the gauge shuold be mounted on the feed line before the fuel rail. measuring fp after the injectors will not be the same as what most of us do in measuring the fp. the stock fpr keeps your fp above 40 psi and the afpr boosts that up accordingly.
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Old 09-10-2006, 08:36 PM   #34
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No to everything stated except the last portion where asked "Am I missing something?" That gets a yes.

The stock FPR reacts to vacuum but does not react to boost or anything over atmosphere pressure inside the intake manifold. Between -22hg (idle) and atmosphere the stock FPR boosts fuel pressure roughly 5-10 PSI. Have not found any two that are exact but really makes little difference in closed loop. Fuel pressure at idle runs about mid 30 PSI to mid/low 40s at atmosphere and just prior to boost.

The supplied Vortech will only react to boost pressure and is invisible to the fuel system when not under positive manifold pressure. An adjustable AFPR such as the BEGi will raise fuel pressure while still under vacuum. This should start happening at around -3 to -5 "hg to make the boost transition much smoother.

The set up you show will only show What the AFPR is clamping and not the pressure in the fuel rail. The only way I see to be able to do that would be removing the hood, sit on the engine to read the gauge while a helper drives under boost.

Other posters are correct. The pressure gauge needs to be fuel IN line before it enters the fuel rail. If wishing to make a dual feed fuel rail, why not just put the sendor before the fork?

Sequence: Fuel tank .. fuel pump .. fuel filter .. fuel IN line .. pressure gauge/electronic pressure sensor .. front of fuel rail .. fuel rail and injectors .. stock FPR .. AFPR .. return line to fuel tank.
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Old 09-10-2006, 10:24 PM   #35
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No to everything stated except the last portion where asked "Am I missing something?" That gets a yes.
Quote of the year!!! And another thread for my archives. Thanks Pop!
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Old 09-11-2006, 11:56 AM   #36
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Quote:
Originally Posted by TurboTim View Post
I was thinking the same thing. Looks very nice! No A/C helps give you room for that drain line too
Thanks for the kudos, guys.

I removed the A/C a while back since it didn't work anyway, and my DIY intercooler bracket hange from the condenser mounting points. Also, I found it helpful to drop the steering rack while drilling and tapping. I didn't remove it entirely, just disconnected the fluid lines and shaft and removed the four bolts holding it to the subframe, then let it hang by the tie rods. I used a Makita right-angle drill and a Uni-bit, since the drill bit that came with the tap was too large to fit my drill chuck (non-stepped shank). Unfortunately this resulted in a lot more shavings ending up in the pan than I'd hoped but I was able to get most of them out with my finger, some Q-tips, and a lot of grease.

If anyone wants to duplicate this drain / supply setup I'll be happy to supply links and part numbers. I also have some -8AN and -4AN hose left over you can have for free. Just be sure that all of the hose ends you buy are the NON-swivel type, otherwise you'll never be able to pre-tension the twist into the hose.

These are the "after" pictures of the Tony DP. A local shop (Electro-Tech Coatings in San Marcos, CA) plated it for $75. Also, you can see that I've put the O2 sensor fitting in a somewhat non-standard position- this made it a lot easier to access and also made room for the EGT probe which I placed in what would be the standard O2 location on a stock Greddy downpipe.

The downpipe is definately a tight fit in a few spots, but it's a lovely piece. Unfortunately you can't see much of it now that the heat shield is in place, but I know it's there. For those of you who are undecided about ceramic coating- do it! I almost can't believe the difference that it makes. After a good hard run I can barely hold my hand 3" from the turbine casing, yet the area behind the DP is nice and cool.
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