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Vacuum diagram needed for EA82T w/spider manifold


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So, I am currently in possession of a heavily modified 1987 XT turbo. The car has been epically messed with by its previous owners; despite being an early 1987 with the flapper-style MAF it has been converted to a "spider" intake manifold and the thing is an absolute vacuum NIGHTMARE. Someone deleted the charcoal canister at some point, among other "changes", and the thing drives like absolute crap - it always feels like it's bogging down and doesn't feel right building boost despite the VF11, TWE up pipe, intercooler, etc. Many vacuum lines have been capped, looped, and other nonsense that surely isn't helping. The TPS has also been flipped to fit the spider manifold as described in this thread: http://www.ultimatesubaru.org/forum/topic/73316-ea82t-4-plug-computer-id/?p=604816

 

This weekend I am going to go back to the workshop with a timing light and go through a few other checks, but I could REALLY use a pic of the vacuum diagram for a turbo car with a spider manifold to compare to my original diagram. Can anyone help with such a thing?

Edited by ShakotanBoogie
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I have the 88 fsm, but this will only identify the port on the spider. This car has the correct disty with knock control unit, but only one vac line on the vac advance, wheile other models have 2.

 

So this car is going to be comparing an early model 1987 with 1986 with 1988 retrofitted in. The 88 spider intake is meant for a 88 with hotwire maf and electronic disty, where an 87.5 spider has an extra piece for hte distributor vac advance which we do not have.

 

What we will need (as i am confused with this car, and i am the one who put most of it together as it is) is identifying boost port and vacuum port, restoring boost switch and vacuum solenoid functions, identifying and either restoring or completely deleting the purge control solenoids, and installing a series of check valves that are presumed missing for cabin vacuum (heater control) pushbutton 4wd (diff lock) and vacuum advance.

 

It may be likely to just strip the manifold down to nothing and start over, rebuilding each vacuum circuit from scratch.

 

The car drives as if the timing does not advance, or the fuel cuts out. once the engine reaches boost, if falls flat and does not rev out, even with more pedal, and the EGT climbs to the sky. Seems like it s fueling while accelerating, but not at cruise.

 

if staying out of boost, the timing advance seems to be working, if you drive with light load, but once the car levels out (low load), the fuel cuts out until you give it more pedal, or you let the car slow down enough while maintaining the same pedal for it to go again. the fuel cuts out on decel, but it picks back up on idle. the car idles ok enough, but stalls a lot coming to a stop.

 

for anyone familiar withthe infamous monsterwedge, here we go.

 

save all the 'don't blow up your ea82t' and 'ej it' comments as we need specific information and advice on the vacuum systems with either keeping the spider manifold, or restoring back to a conventional manifld wile keeping the flapper MAF and 85/86/early87 engine management with external KCU

Edited by MilesFox
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There are a couple 1987 XT FSM's on ebay, I'm tempted to buy a set just to upload scans. I know gloyale has posted some of the wiring diagrams, perhaps he could post up the vac line diagrams as well.

I have considered doing the same but unfortunately I'm between jobs and nobody wants to buy any of my parts, so it's hard to justify the $80 right now. I did message Gloyale after finding the other thread, hopefully he can come through!

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There are a couple 1987 XT FSM's on ebay, I'm tempted to buy a set just to upload scans. I know gloyale has posted some of the wiring diagrams, perhaps he could post up the vac line diagrams as well.

This car would really take a 1988, 87.5 and 86 FSM and someone who knows what they are doing to figure out. Throw a legacy turbo, an ford intercooler, and a vlolvo recirc valve on top of it.

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EGT climbs high, and you suspect ...

 

I am confused

 

falls flat on boost, which is essentially accelerating , yeah ? fueling on acceleartion or over fueling, or under fueling, what do you mean by fueling ?

 

overfueling would help lower EGT ? I is the exact opposite with LPropaneG and Diesel fuels though

 

fuel pressure reg, where's it get its vacuum source ?

 

Coz, you know, my original fuel pump on my 85 turbo would survive idle, stationary revving, take off, but as soon as boost was asked of it I saw pressure gauge Teed into the line, strapped onto windscren, would then drop from mid 30's to 10 psi.

 

New pump fixed that, so is your prob coincidental in that as son as you swap manifold pump gets ill ?

 

? Have you also tested fuel pressures on road?

Also curious to know what you expect in power.torque etc from the manifold swap once sorted ?

 

"where an 87.5 spider has an extra piece for hte distributor vac advance which we do not have."

 

what? what is this extra piece you talk of ?

My 87.5 spider does not have any vac advance on distributor at all

85,86 turbo mpfi fuel rail spaghetti includes a metal vacuum transfer tube from the distributor side of front of throttttle body of the two ports - other end is just near dizzy and feeds vac advance cannister.

 

Think I have seen early EA82T XT NA 5Sp manual with two piggy backed vac cans on its dizzy, so suppose it had two metal transfer tubes from two different vacuum sources ?

Edited by jono
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EGT climbs high, and you suspect ...

 

I am confused

 

falls flat on boost, which is essentially accelerating , yeah ? fueling on acceleartion or over fueling, or under fueling, what do you mean by fueling ?

 

overfueling would help lower EGT ? I is the exact opposite with LPropaneG and Diesel fuels though

 

fuel pressure reg, where's it get its vacuum source ?

 

Coz, you know, my original fuel pump on my 85 turbo would survive idle, stationary revving, take off, but as soon as boost was asked of it I saw pressure gauge Teed into the line, strapped onto windscren, would then drop from mid 30's to 10 psi.

 

New pump fixed that, so is your prob coincidental in that as son as you swap manifold pump gets ill ?

 

? Have you also tested fuel pressures on road?

Also curious to know what you expect in power.torque etc from the manifold swap once sorted ?

 

"where an 87.5 spider has an extra piece for hte distributor vac advance which we do not have."

 

what? what is this extra piece you talk of ?

My 87.5 spider does not have any vac advance on distributor at all

85,86 turbo mpfi fuel rail spaghetti includes a metal vacuum transfer tube from the distributor side of front of throttttle body of the two ports - other end is just near dizzy and feeds vac advance cannister.

 

Think I have seen early EA82T XT NA 5Sp manual with two piggy backed vac cans on its dizzy, so suppose it had two metal transfer tubes from two different vacuum sources ?

You would have to see this car, it is a mess. it has been built by several people over the last 15 years, well documented as the 'monsterwedge' and the last guy who had it had no clue what he was doing, shotgunning parts onto it, and making a mess of it.

 

I don't know how to describe it unless i can reverse engineer this chop job and make a schematic, so then that i can reference it. It just doesn't run right, is untuneable, and would need to be stripped down and start over from the ground up with vacuum routing.

 

the biggest confusing part is this; do the math:

1987 xt mpfi turbo, flapper maf, mechanical disty

full xt6 interior swap with some xt6 harness for the diff lock that blows fuses when turned on

88 mpfi spider intake from n/a/ the 87.5 has some sort of part with a port on the driver side of the manifold that is not present on this manifold. botht he 87.5 and 88 are designed with optical disty and hotwire maf

no boost switch is present, charcoal can is gone, purge control solenoid goes to nothing, several vac ports on the box part of the spider mani and 2 on the throttle body.

the engine is a carb block form an 87 wagon, the heads are one gen2 and gen3 found on an 87 rx with egr. There is no egr in this car, although it probably had one originally with a conventional manifold.

 

The fuel pressure regulator seems to be hooked up. So far as i can tell, there are no check valves anywhere in th vacuum lines. We truied connecting the disty and the recirc valve to the ported vacs on the TB.

 

The vacuum diagram under the hood correlates to a conventional manifold, which does us no good. Also, we had no access to a timing light or a vacuum gauge to troubleshoot, or any comprehensive schematics.

 

I know the 85-86 and early 87 share the same electrical schematic. the 87 may have different pigtails then 85/86.

 

All of the components are known good units, fuel pump, injecotrs, IAC, ECTS, plugs wires cap and rotor, new timing belts, timing belts correct, disty timing should be correct.

 

What i need to know between the disty, recirc valve, and cabin vacuum, is which goes to ported vacuum, which to manifold vacuum, and were should check valves be in between.

 

This car is a garbage build better deserving of a ej20, but for the fact that is is complete we want to make the ea82t work for the sake of accomlishment so that we can be disappointed when it cracks a head, thus justifying an ej20.

 

The only thing that makes this car worthy of a project is considering its heritage, having been documented over the last 10 years on the subaru forums, and the fact that is was first registered to SOA as a dealer promo car when it was new.

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Fox pretty much hit the nail on the head. I have built a handful of modified turbo Saabs and Audis in my years without issue but Trionic and CIS are a much different animal than the vacuum-driven nightmare on this XT.

 

The car drives (and smells) as if it is running rich under boost but the EGTs would seem to indicate a lean condition. Boost is currently turned down to 6psi to prevent severe damage until the problem is figured out. When I first got the car I spent weeks replacing oil-soaked boost hoses and vacuum lines which has made the car start and run BETTER, but still not CORRECTLY. I replaced all vacuum components as they were originally run, which is now known to be incorrect. The car is slower than a regular carb EA82 at this point let alone the EA82Ts I have driven in my time.

 

With a vacuum diagram from a proper turbo spider EA82 and the diagram we already have we should at least be able to create a similar vacuum circuit in order to make the car run and drive in a functional fashion.

 

Yes I know EA82Ts suck but this car has history, let alone one of the hyper-rare TWE up pipes so I would at least like to have the pleasure of blowing a rod out of the block with it running correctly and a smile on my face.

Edited by ShakotanBoogie
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You got a fuel tank, surely you gotta start with a charcoal canister to deal with the line from the tank to the char can and the fuel smells. If you see two ported vacuum ports on TB, the one that is on same side of throttle body as cannister, supplied the cannister, but if flipped the TB to fit spider, it is other side

 

Miles has already said this next bit, so excuse me for repeating it :)

 

Take yourselves back to the sixties with the engine , plug off unnecessary vacuum sources, PCV valve, shove small filters on rocker covers breather vents, block off EGR, vac advance to dizzy not needed entirely, just ensure you have vac booster for brakes and vac for FPR. edit, sounds like this has already happened ....

 

"What i need to know between the disty, recirc valve, and cabin vacuum,
is which goes to ported vacuum, which to manifold vacuum, and were
should check valves be in between."

 

recirc valve - EGR valve gets manifold vacuum via a solenoid which is switched by the ECU - generally only operates between 2 and 10 in Hg , supposed to be also only at op temp and below 45kph. Mine ran all the time, no matter what temp or speed. If it had 2 - 10 in Hg vacuum, it opened.

 

Cabin vacuum must be last on your list? Does not affect GO factor ?

 

What is your idea of what a check valve is ? A one way valve ? Or restriction orifice to soften the vacuum source ?

 

Add one system at a time and ensure she runs right after each addition.

 

Surely if you start with original 3 plug ? ECU and all its mates, flapper afm, same throttle body just adapted to fit the spider, same dizzy (wil still run even with knock moule disconnected) same coil to match - did not have the transistor mounted coils of 87 onwards mpfi on 3 plug ECU, timing set right for upped comp raTIO - about 10 BTDC worked in southern hemisphere on carb block with turbo. What sort of cranking pressure you got in the pots?

 

It has knock sensor control which will pull timing back - this can be monitored at least on 85.86 sedans ( don't think I found it on my 86 build EA82T XT ?? ) where a white plastic connector, female spade sitting minding its own busineess near the coil.

Must be another check plug terminal to get this reading, monitor that it has 5V on start up, settle to 1.7V running, if it ramps up to anything above 1.7 towards 4.5V max it is retarding the timing, and you can see that on the flywheel.

If you running carb or spfi compression with nice turbo maybe you are getting knock, or is knock sensor too sensitive , operating correctly ??

Edited by jono
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It won't run right without a closed PCV system. The PCV system is something that was corrected, to get a cross flow ventilation. My experince with ea82t's is rough idles and such were caused by ill fitting oil caps or dipsticks.

 

We'll get some detailed photos next time. I had limited time to drive and pole at the car. I was afraid to drive it too far for the fear of having to push it back.

 

I am not sure if there is difference between USDM aud AUS market for the same year. We get all the watered down EPA friendly crap here with all of its 115 hp.

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So......Spider intakes should have all been hotwire type.....even an 87.5......

 

.....How is the TPS mounted?

 

If it's a 4 wire TPS.....it's an original spider one for the hotwire system.

 

If it's a 3 wire one...it's for a flapper setup (just an Idle switch and a WOT switch)...but those would operate backwards rotation if placed on a spider manifold.  So it would think idle at WOT and vice versa.

 

Workin on scanning some FSMs right now.....but the TPS thing is jumpin out at me as a potential issue.

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Ha.....that's awesome......I made that one and tried it out in theory....but never seen anyone actually running one.

 

Still installing scanner software.

The included Nuance software allows you to export scans in .jpg, .tif, .png as well as .pdf Gloyale.;)

Edited by czny
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Here are some pics of what we are working with, FWIW. Basically, an absolute codswalloping mess. To clarify/reiterate: this is an EARLY 1987 XT turbo with the flapper MAF and 3-wire TPS that has had the spider manifold, VF11, T-bird intercooler, Volvo BOV (now replaced with a simpler Bosch unit leftover from my Saab 9000) and TWE up-pipe slapped on in rapid succession by previous owners who seemed not to have a full understanding of what they were doing. The vacuum routing is (clearly) a nightmare, charcoal canister was thrown away by a previous owner and purge control runs to nothing, and many lines are either capped, looped or run in a nonsensical fashion.

 

image-66.jpg

image-65.jpg

image-67.jpg

image-64.jpg

Edited by ShakotanBoogie
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Agreed, those diagrams are fantastic ! I can now see the altitude wire from kcm to ecu not in my 85,86 manuals - yet I hav a US kcm to use one day, so this diagram is of use to me too. Thanks :)

 

It is funny you mention loose dipstick or oil cap affecting operation, as when we first got efi on common old Fords as an option for starter on the 4.1 I6's word was if you left one out, off or even the fuel cap - would not run - never saw it though ?

 

Mos EA82's I have got came with near clogged PCV hoses and vents, might have contributed to health issues of non going engines, always cleaned up before ever running them, so again, never saw results of clogged PCV.

I have done though 2 so far EA82T and NA, with each rocker cover vent fed off to the air filter boxes, separately, without considering one should be in the draw through position (closer to outlet to engine side of things) more than the other, and never had any issues.

 

I was suggesting, just forgot to say, I think a spark plug fits in PCV valve hole, surely that will block things off and not allow any PCV issues to upset the running of the engine ??

 

Nice pics by the way.

 

Just can't help notice less cluttered hoses on the passenger side back corner of the spider body. Mine's  a bastard and the plastic elbow seen further away is really tucked up close on mine.

And TPS - you are saying the TPS unit on side of TB is the 3 pluggers TPS adapted to fit the spider TB ? Or you have complete 3 plug TB and TPS adapted to the spider body ?

I have a spider that has a throttle body and TPS adapted to it I think, given the surgery on the wires and resulting dodgy looking finish.

If I can find it, I'll have a look see what wires joining what wires if need be

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  • 4 months later...

Old thread digup :P

Mainly cos I see those in the know are already here.

 

I'm installing a spider manifold EA82T into my 89 NA MPFI EFI Touring wagon.

 

The engine has the wiring loom attached, but being from an XT, it comes out the back, not the side.

I have a "gold" turbo ECU to fit also

 

I'm considering the following options:

1. remove the loom from my NA engine, modify it to reach the required sensors in their different positions. Except I don't know what sensors are where on the spider engine

2. make a patch loom that plugs into the spider's engine loom across to the wagon's body harness. again, I need to know what sensors are what so I can trace the wires.

 

help please....

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