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malcpw 05-25-2007 03:15 PM

What do you think?
 
4 Attachment(s)
What do you think!

My setup.

T25 from Nissan 200sx 1.8.
5th injector on outlet from turbo compressor(as E-Cool)
Vac switch to activate 5th injector and forces ECU onto WOT maps as manifold vac drops through 1" of vac.
I'm running std timing 10deg. 8psi boost and no knock and no intercooler!
Have voltage control to AFM to control fuelling at WOT on boost
Home brewed adj fuel press reg - extra 10psi of fuel
Narrow band led meter to give some guidance on state of mixture. Mounted in boost gauge pod next to gauge.
Home brewed steel tubular exhaust manifold, stainless MIG welded - stainless head flange from scrapped/damaged std manifold, stainless flange to turbo.
Home made flange from turbo into 2" pipe from turbo and parallel 1 1/2" pipe from wastegate into tappering section to 3" stainless through 3" Warlock silencer. Some bends are crush bends so not so good but still plenty of area.
Crossover tubing donated by Volvo 940 and a turbo Saab something!
Recirculating BOV as per Saab 93 brand new from Mill Autos less than £17!! Recirculating necessary as bypass air contains some petrol.
Home made aluminium NACA vented head lamp cover. Lumi weld is great for this sort of thing.

[Nothing to do with above performance mods, or perhaps everything, 1.8 brakes all round with Mintex M1144 pads up front, KONI adjustable adjustables(no it's not a stammer) with AVO 300lb/in springs up front and 200lb/in springs at rear.]

Problems so far - after first running up to full temp and cool down, manifold pulled flange to head out of true probably due to stress relieving and flange being a little thin only 10mm - 1/2" would have been stonger. Removed and filed true (I'm an engineer of the old school). Now done 200 well boosted miles and no reoccurance of problem. Underestimate heat generated by manifold so some appropriate heat shielding put in place has resolved problem. I'd already made some room for heater tubing at back of head.

Now can I download crummy photos from photobucket?
Attachment 216458

Attachment 216459

Attachment 216460

Attachment 216461

Those welds don't look pretty do they.

I think that's done it.

Malcolm

mazda/nissan 05-26-2007 12:10 AM

about the 200sx 1.8, the 200sx's have 2.0 liters right? hence the name 200sx, 350z having 3.5, 240sx having 2.4, i'm a bit confused...do you mean the sr20det turbo form the silvia's?

malcpw 05-26-2007 03:48 AM

The 200sx I believe came in 2 forms S13 1.8 and S14 2.0.

S13's had T25 and S14's T18 turbos.

I believe that's correct but will stand correction.

Malcolm

Rage_Kage 05-26-2007 05:04 AM

no no no the 200sx was the s12 the first gen 240 was the s13 and so on, i

magnamx-5 05-26-2007 08:06 AM

yep 240 is the s13-14 KA24 in the US SR20 in JDM

malcpw 05-26-2007 09:21 AM

Nissan 200sx came in 1.8 and 2.0 motor sizes.


Engine Year Turbocharger Details OEM Part No. Comments RRP Price £
1.8L P 88-94 TB2525 G 465795-0001/3/4 14411-44F01 oil pipe kit 450
2.0L P 94-96 TB2809 G 466543-0001 14411-75F00 660
2.0L P 96- TB2815 G 471104-0001 14411-82F01 660


Perhaps US designations are different


Malc

y8s 05-26-2007 10:50 AM

now that is diy.

it's rough but looks pretty functional to me. the primary exhaust tube before the transition might be a little on the small side costing you some spool but if it works... cool.

as for the welds, more amps!

juhanis 05-26-2007 12:44 PM

i'm digging that manifold... thats awesome.

malcpw 05-26-2007 01:39 PM

The internal dia is about 1 3/8" and although outside is rough inside is carefully aligned and pretty smooth. I wanted quicker spool up so keep dia. and therefore volume lowish rather than bigger and more top end.

I tried to get a narrow angle where the four pipes join and it seems to have worked out well enough.

The driveability is really good. At least as good as stock before boost. Starts to build boost at 2000rpm. Power continues to build very smoothly to the rev limiter without any hiccups.

It's now the sports car it should have been. Making overtaking on our narrow Cornish roads so much easier and powering through the windy bits so much more fun.

Thanks for your comments and interest.

Malcolm


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