North American Turbocoupe Organization



turbo psi
Noname
Unregistered
#1
hi, my name is don. i just bought a 88 thunderbird and the psi on the turbo is only at 4psi i was wondering if there is a way to turn it up? thanks
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SteveX82 Offline
Posting Freak
#2
4lbs of boost? Wow, I've never heard of any combination of problems causing the boost to be that low. First of all, does the engine itself seem to be running alright? If it stumbles or hesitates once it reaches that 4lbs of boost, it's possible you have a boost leak somewhere or a faulty sensor. At what gear/rpm are you seeing the 4lbs of boost (most tc's don't reach the full 15lbs until 2600rpm in 2nd gear, or 4500rpm in the upper 3 gears on some cars). You can buy a boost control valve to try and manually adjust the boost you car is receiving, but I think it's best to determine what's wrong with the turbo/engine first. Let us all know the answers to those questions and we'll try and start diagnosing your car's problem. By the way.....welcome to the board [Image: wink.gif]

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maroon 1987 TC 5spd

gillis valve set at 18lbs, k&n cone on VAM, removed A/C belt, unbolted exhaust at track,
best 1/4 mile: 15.10 @ 89.25mph

NEW UPDATE: car is fixed and better than ever. New mods include mildly ported TB and exhaust manifold, removed a/c system (free mod, but still), kirban adjustable fpr (at whatever the stock setting is now, but changing once i get a fuel pressure guage), and a spare ihi turbo i had laying around. 14 second 1/4 mile times, here i come
Estoril blue 1987 TC 5spd, 148k mi, a237, Bailey BOV, spec stg3 clutch, spearco FMIC, 50 trim t3/t4, 3" exhaust, Bamafuel, LM1, 55pph
Best 1/4 mile: 12.31 @ 110mph on 25psi
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Noname
Unregistered
#3
ya, the engine does seem to be running very funny. today i drove 120 miles and burned up a full tank. it is studerin when the turbo hits and its exaust is pretty thick too
the 4psi normally hits around 2000-2500
oh and thanks, im glad to be here.
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segfaultxr7 Offline
Posting Freak
#4
A full tank in 120 miles?!? Yikes!

Well, that's definitely a problem that should be addressed before continuing. Do you have a check engine light? It's probably a bad O2 sensor, they will tell the computer the engine is running lean, so it dumps a whole lot of gas and makes it run really rich. It could also be the fuel pressure regulator, but you should scan for codes first.

If it's been running that rich for any amount of time, it probably melted the catalytic converter. That makes a big exhaust restriction and could explain why you're only getting 4psi.
88 TC 5-speed
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Pete D Offline
Administrator
#5
Test for a restriction in the exhaust first. Get a vacuum gauge hooked up to the vacuum tree which is on the top of the firewall near the master cylinder. All vacuum lines run to the vac tree. Hook the gauge to a free port or T it into an existing port. With the engine warm take it up to about 2000 rpm. While watching the needle on the gauge, close the throttle rapidly. The needle should instantly spike up to 20+ hg. If it pauses slightly before spiking then you have an exhaust restriction such as Segfaultxr7 suggested. That could explain the low boost.
Next you need to pull the codes from the EEC IV computer. See the FAQs (link at top of this page) You need to report the codes in the order the computer reports them. It may be an O2 sensor but it can be other things also. I would also do a complete fuel pressure check. Let us know what codes you get. E-mail me of line if you want the fuel system diagnostics.

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88 TC X 2, 86 SVO, Main TC with K&N, 3"DP to 2.5"duals through Dynamax, Ric valve at 17+ and disconnected KS.
Elite Bodega 16" chrome wheels. Autometer pod w/ A/F and Vac/boost gauges.140 mph Motorsports Speedo New engine: Total Seal rings and TRW pistons, ported and polished head w/ cc'd chambers,1.59"exhausts, SS valves, gutted upper, knife edged lower, A-230 cam, Race Engineering Adj Cam Sprocket, Crowlers, ARP head studs, and rod bolts. Walbro 255 HP pump and Kirban adj FPR, T-3. Centerforce II, KB subs and jack rails.

[This message has been edited by Pete D (edited 10-27-2001).]
Pete Dunham


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Noname
Unregistered
#6
im running strait pipes to glass packs and i have no catalic converter.
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Noname
Unregistered
#7
i changed the 02 sensor but i found a small gas leak neer the engine i dont know what to do now. the turbo is still running at 4 psi
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Jeff K Offline
Administrator
#8
Quote:Originally posted by fbmbiker:
i changed the 02 sensor but i found a small gas leak neer the engine i dont know what to do now. the turbo is still running at 4 psi

Leaking O rings on the injectors is a relatively common problem brought on by age and heat. Replacing the O rings is pretty easy. The pulse damper (can on the firewall side of the fuel rail) has also been known to leak, as well as the fuel press reg (can on the front of the rail). Try to narrow down the cause of the leak.

Did you run the EEC diagnostic codes? If not, do so. See the link on the home page for some info. Post the results of the code test.

Lastly, feel free to ask any question, no matter how dumb is may seem. Unlike many boards, you wont get flamed here just for being a newbie. We are all here to help each other.

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Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 20 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 00 Windstar (wifes vehicle)
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
11 Crown Vic Interceptor
14 Toyota Camry (wifes car)
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized
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Noname
Unregistered
#9
where would i fine one of those eec testers??? i dont have a clue on it
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1987tc Offline
Senior Member
#10
You can get a code scanner at any parts store. Sears has them too. Cost is anywhere from $25.00 on up. Most will come with a book that tells you what the codes mean as well as directions for getting and cleraring the codes.
Wes

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1987 TC:
Hurst compition plus shifter,K&N cone,roller cam,custom single exhaust,Gillis valve,H&R springs,KYB shocks,struts and quads.
3.73 rear.
Tubular rear control arms and Kenny Brown trac kit brackets.Mac rear differntial cover and girdle. soon to come, Installation of Caster camber plates and a custom built roll cage.
Wes Arnett
Linton Indiana
Sold my Turbocoupe. It went to a good home.
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