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Old 05-09-2007, 08:01 PM   #1
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Default Time for my very own build thread! (oh god please help me)

The finances are slowly coming together, I'm doing the final bits of research, and D-day is just under a month away. The goal is to start the install during the first week of June. so it's time to wrap up the loose ends and get the final bits ordered.

The car:
'94 1.8, 130,000 miles

The setup
(already ordered):
T25 .48/.49 turbo
eBay front mount
coldside IC piping
Bosch BOV w/ check valve
460cc Rx7 injectors

(already installed):
ACT 1.8 HD, OEM flywheel, 6-puck disc
Oil temp, boost, EGT, Innovate WBo2 gauges
Aluminum 2" radiator

The rest of the setup (not yet ordered, open for suggestions):
DIYAutotune MSPNP for '94, when it comes out, with:
-GM 4-bar barometric IAT sensor
-KnocksenseMS
BEGi exhaust manifold and 2.75" stainless DP
Carsound 3" high-flow cat
Enthuza 3" stainless turbo catback
Hotside intercooler piping from Treadstone Performance
Oil/water lines from TheBandit
MBC from someone. Suggestions?

The goal is as much power as possible (hopefully 210-220rwhp) on 12psi and ****-water 91 octane, and 240+rwhp on 15psi and race gas. The focus of the setup is really on spool: I want boost onset under 2000rpm with 10-12psi at 3000rpm. Water injection is not out of the picture for the future to combat the heat of spinning the small T25 that hard, but first I need to get the setup running and tuned on straight boost. What am I missing? What should I look into?
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Old 05-09-2007, 08:15 PM   #2
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Make sure that we get some good pics of the build!
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Old 05-09-2007, 08:23 PM   #3
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I'm happy with my ACT HD as well as my BEGi mani and dp. I bought a $15 voodoo ebay mbc last night since samnavy said he was happy with his. (You have to trust a guy with a name like Sam)

Edit: +1 on lots of pics
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Old 05-09-2007, 08:31 PM   #4
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Looks good to me. Ask Corky if he'll swage your dp out to 3" for you. They seem to love custom stuff, so I doubt it will be a problem, and that will make things easier for you. Also have him weld in a bung in the mani for your EGT probe, and specify your WB bung in the dp to be pre flex section and FACING UP. For whatever reason, they keep putting the o2 bungs on the bottom of the pipe ???

As far as MBC's go. I really like the Forge that I got from member PAT!. The ratcheting action is nice and precise. Easier to work with than the FM MBC it replaced, and more precise and stable with the ratcheting locks. (with the FM you have to remove the tube to spin the body to retension the spring, then reconnect the tube when you're done). Also, maybe DIY will develop EBC with the MS.
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Old 05-09-2007, 08:52 PM   #5
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you said bung
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Old 05-09-2007, 08:53 PM   #6
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He wants his bung to point up
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Old 05-09-2007, 08:57 PM   #7
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I'll buy your 6ul's to give you that extra cash you need
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Old 05-09-2007, 11:03 PM   #8
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Quote:
Originally Posted by SamS View Post
He wants his bung to point up

that only works if you mount it correctly...
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Old 05-09-2007, 11:33 PM   #9
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YESSSSSSSS more of us.
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Old 05-12-2007, 06:55 PM   #10
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http://cgi.ebay.com/ebaymotors/ws/eB...m=280114048537

Bought that last night. Injectors are on their way back. Next thing to get sorted is the oil and water lines. Can anyone tell me what sized fittings a standard T25 from Garrett would use? :(
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Old 05-12-2007, 06:58 PM   #11
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Should be a 7/16 inverted flare fitting at the turbo.
It is a Nissan T25 isn't it?
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Old 05-12-2007, 07:11 PM   #12
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Quote:
Originally Posted by cjernigan View Post
Should be a 7/16 inverted flare fitting at the turbo.
It is a Nissan T25 isn't it?
No. I picked it up off eBay. It's a .48/.49 T25, smaller than an SR20 turbo, I'm pretty sure. There are a couple of small Garrett plaques on the sections between the oil and water fittings, and a larger plaque on the compressor housing next to the wastegate that says "Advanced Turbo Systems" and gives a part number and a serial number.
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Old 05-13-2007, 03:08 AM   #13
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7/16 i.f. should work for your oil feed, i'm working with a mitsu t25 (smaller trim than the nissan flanged t25s) and a 7/16 i.f. worked perfecto
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Old 05-18-2007, 03:08 AM   #14
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All rightie. My MBC arrived today, so the next thing on my list is to figure out the hotside intercooler piping. It it absolutely necessary, highly recommended, or just a good idea to clock the compressor so the outlet faces down instead of up? I would love to avoid taking apart a brand new turbo to drill it for the wastegate mounting bracket. I'm hoping the BEGi manifold will situate it low enough that I can just use a 90 and come out straight, then use a couple of 45s to get the piping down to the side of the intercooler.

Second thing is the PCV valve. I've heard several users say to just remove it, and several say that the 323 GTX PCV valve is what I want. What's the deal with it, and if I need one, where can I find one?
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Old 05-18-2007, 09:36 AM   #15
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In case you didn't realize, there are no pics in your posts.....
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Old 05-18-2007, 04:50 PM   #16
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I know. I'm ordering the manifold and downpipe on Monday. I just want to know whether anyone's NOT clocked a T25 and just used 90s and 45s to route the piping to the intercooler, rather than clock it and then use a single 45 to achieve the same thing.
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Old 05-20-2007, 04:25 AM   #17
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Looks like akaryrye is, so it's definitely possible. I'm just going to go that route. I doubt I'll have lag issues with a .48/.49 turbo.

I just got a big paycheck ($900) so I'm going to order the downpipe and manifold from BEGi on Monday. They sent me a few photos so I could mark for EGT and wideband bungs. The EGT bung looks pretty obvious:

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but I've heard that I want the wideband bung horizontal, not vertical. Where, exactly, though, is the best place to stick that in the downpipe? BEGI sent me these photos to mark:

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Old 05-20-2007, 06:23 AM   #18
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i would go somewhere right before that flex joint for the wideband bung. because you're getting the wastegate gases also. i'm sure someone will disagree with me on that... but oh well, thats about where mine is, and it works fine. it should be within about 2 feet or so of the turbine also. plus you wont be lagging with an exhaust ar such as those ones. mines .70 and its like a switch. then again, its a completely different turbo and i believe for like 40bucks or less you can make your own lines from royal brass in san jose, they even have braided lines if you want to go fancy. i just use the normal working mans high temp blue silicone hose with a 5/8" hydraulic pushloc hose as my return. i use normal coolant hoses for coolant, duh. cheap effective and local, and they will also custom make you oil lines if you need. oh yeah, arent the rx7 injectors high impedance? guess that doesnt matter all that much. a manual boost controller will get the job done but they dont protect from spikes and the boost is a little tricky to move around without test runs. i wonder what that t25 is capable of moving (cfm wise). it may be out of its efficiency range at the higher boost areas. but it'll definately spool with the quickness. okay, i'll shut up now.
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Old 05-22-2007, 11:11 PM   #19
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Ordered up the manifold and DP yesterday. BEGI was able to step it up from a 2.75" at the end of the DP (right before where the wastegate collector merges in, back to the flex piece and the flange) to a 3". I'll be picking up a standard 3" cat this week and ordering the Enthuza 3" turbo exhaust next week.

Only one major thing left, and that's the ECU. Depending on timing, I'll either be running a PNP MS (preferred) or parallel-wiring it. After that, it's just nit-picky stuff: hotside intercooler piping, figuring out connectors for the PCV valve, IAC, and BOV (running VTA with a check valve for now), and oil/water lines.

Install starts next week. I'll post pictures.
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Old 05-22-2007, 11:26 PM   #20
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Get the oil and water lines on order. They can sometimes take a while as the 7/16 to -4AN fittings are sometimes out of stock. Just a fair warning as it took 3 weeks for my supplier to get them in last time he ran out.
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