Ea82 4wd auto Weber

[GrizzlyFox]

Hey gang,

So as of now, my 88 GL wagon, aka Mountain Grizzly Mk2, is my daily driver. I have owned the for some time now and have been slowly upgrading it to better suit my needs, and as things have worn out I've tried to retrofit and overall improve on it. 

When I got the car, it had way too much carburetor, a 600cfm 4 barrel. It was originally spfi. I used an ea81 intake and  carb that I had kicking around to make it more driveable, then swapped to an ea82 carb and intake in hopes of better performance. Now about a year later, the new old stock carb I used is giving me some trouble, and I think before I bother with a rebuild it may be time to swap to the Weber. 

My main hold up is wondering if I will see a decent gain in performance. The car being a 3at is hopelessly slow, and I'm wondering if my money is better spent swapping in the  5 speed. I have a source for parts but nothing on hand for the swap. I'm not looking for a hot rod, but just something that will do 65mph without taking forever to get there. As it is now, the car is struggling to maintain speed climbing small hills, and has to be driven at full throttle most of the time to hold a steady 55mph. 

More info on the car itself.

195/60/15 winter force 2 tires, 6 lug swapped. Engine is originally an spfi ea82, xt6 pistons, full rebuild around 30k miles ago. Delta cams, 2.25 in exhaust from the header back to a turbo muffler. Engine is making a solid 20in vac at idle 

[DaveT]

I had a carbed 86 4wd 3at.  It takes a while to get to 65.  4000rpm at 65 is normal.  Steeper hills would need close to full throttle.   This is with stock tire size.  Running bigger diameter tires is like a higher top gear, so slow everything down, especially with the marginal power from a Hitachi carb.

Iirc, the SPFI makes a little more than 10 more HP.

[GrizzlyFox]

Good to hear from someone who has some seat time in a carbed auto car. I've had autos, and carbs, but never a car that was both. It seems that my 3at spfi loyale wagon was a pretty capable highway runner despite the high rpm. 

It's also an option to find and install all the spfi stuff, but given the age and availability I think the Weber might be more economical and easier to service. I am still using the spfi distributor and computer, just with every other sensor disabled and missing. It was that way when I found it. Fuel pump is wired to a relay and switch. 

Before the current carb issues, the car had no issues keeping up with traffic. I just would like a little more get up and go. 

[DaveT]

I am not 100% what year this change happened, but somewhere between 86 and 90, they changed the final ratio in the 3AT.  Just a little.  My 86 ran at 3600 3700 at 65, my loyales ran at 4000rpm at 65.  Makes a big difference,  as did the spfi vs Hitachi carb.

The ECU running ad you describe  is most ikely operating in limp mode, which is less than ideal.

When they first switched to the SPFI I worried about the reliability. ...  30 years later I am still running the same parts.  Collect some spares..

[GrizzlyFox]

I've wondered about it going into a limp mode, but haven't been able to find any info on that while searching. Also, given that its slowly developed the current carb issues, i figured the disty and ecm were still happy to cooperate. I shouldn't have said that all sensors are missing. , the coolant temp sensor is still there. 

[GrizzlyFox]

Just did some digging on our shops Alldata manual, and it does say that the ecm controls timing using signals from both the crank angle sensor in the distributor and the throttle position sensor. It also mentions going into a fail safe mode, which makes sense. I guess that couls mean it won't advance timing under load without an input from the tps. I wonder if the MAF would play a role in timing control as well. 

[djellum]

couple ideas,

if you still have the spifi distributor in it, they do the initial timing differently.  spifi I believe you set the dist at 20 deg and the computer backs it off or raises it as it sees fit, but carbed does the standard 6-8 deg and goes up from there.  I dont know the spifi distributors well enough to know if they can work on ported vacuum from the carb or if you need a different one but I would definitely check it out.  some people run 20 deg even in carbed motors so you may not have noticed but I find it runs much better set to the lower setting (though mines bumped to 11 for the weber).

spifi fuel pumps are way too high pressure for carbs in a lot of cases, check your fuel pressure.  idk about the carb you have but the weber wont like 20psi incoming.  can get a regulator to bump it down to spec.  Spifi is better than the weber for performance, though some people just like them or started with a carb car to begin with.  if you already have wiring and pump for the spifi then I would do that.

auto trans should function fine but 80's autos sucked in small low hp cars.  not going to be as peppy as a manual, but probably not your biggest problem out of the gate.  

Webers dont give a ton of power boost, they just allow a simpler setup and allow you to change where the power to a lower end curve.  much the same as the delta cams, its more about moving the power around the rpm range.  most weber swaps are from tired stock carbs, but if you compared both new it would be a small increase.  most people overfuel with the webers imo.

 

best option - replace the spifi stuff 

second best - replace the dist with a carb one, or reset it to make sure its timed for the carb and running properly.  weber after this if you want a carb car.

 

[GrizzlyFox]

The car has seemed happiest at about 12 deg timing. The spfi distributor does not have a vacuum advance. Fuel pressure is regulated to 7psi if I remember correctly. It no longer has the stock pump, but an aftermarket inline unit with an old school adjustable regulator. 

I think I'm going to check with the junkyard here locally and see what they're gonna charge me for an intake, throttle body, and the other spfi pieces and compare from there. The easier solution will be a carb at this point, I believe the return fuel line is cut off, and I'll probably need a new fuel pump as well. 

[DaveT]

SPFI distributor does not have vacuum advance, so the timing will be fixed.  SPFI needs 21PSI fuel pressure, or it will be very unhappy.  The CTS main function is to tell the ECU the engine temp so it can act as the choke / fast idle.  The ECU will need the MAF and the TPS to function in anything like normal mode.

[GrizzlyFox]

Any ideas on hooking up a carb disty? I assume it has a completely different type of control module. I couldn't find any relevant data on our shop computer. I would like to swap a carb disty in place of the spfi one if I do continue to keep the carb in place. 

[DaveT]

As far as I remember, it just wires in.  Power, maybe a signal to the fuel pump shutdown?  It still has electronic points.  No ECU.

[GrizzlyFox]

Well, looks like a carb disty is on my list along with the Weber. I will report back with my results. 

[Mack Truck]

Hi Grizzly,  I am just finishing a top end over haul on my 86 GL, with the 3AT that had an original hitachi carb .  I had added a 38/38 Weber Carb at Redline's recommendation. They also stated if i was going to do or had done any other mods to the engine that the 38/38 would be the best as it is a syncro carb NOT  progressive carb.  When i had some tuning and fitment issues they admitted i was the 1st person to use their conversion kit that they knew of. (the carb will not fit normally with the A/C compressor installed, so i turned the carb. 180 degrees and had to make a bell crank so the throttle cable works correctly, and it does)  The carb performs as stated, much better low rpm torque. I added a 2.5in CAT back High Performance Exhaust which helped more.  I messed up and over heated my engine (bad radiator and ran out of water)  and in the rebuild got RV grind cams from Delta Cam. I did my break-in run last week and will take it on a test drive in a few minits, but saw your post.  I do have a vac line to my distributor, and i took all of the vacuum lines off the hitachi as possible and it works well.  ill let you know but my 38/38 really works great, (I have about 20,000 miles  using this carb) im hoping the stage one cam grind does the same for my low end. the transmison is high geared in 1st gear, and i too have 15in wheels and KO2s on it.   Ill let  you know how it goes.  Id suggest you do what you talk about above and consider a vacuum advance distributor then call Redline and consider the 38/38  over the progressive carb that most ppl use.  BTW  i was getting 25mpg on the hwy, which is about the same as the stock carb.  big change in performance however for the same mpg. (during the top end overhaul i have also added a 4in lift kit so i have that to get used to along with the new cams.)

 

 

Edited January 19, 2020 by Mack Truck

[GrizzlyFox]

Good info Mack! Keep me updated. In trying to find time to get over to the junkyard and grab the proper distributor.