Issues with my EA81dc, dying at high RPM.

[Phizinza]

Car: 89 Brumby (Brat) EA81 dual carb, 25" tires.

 

Ok, just 10mins ago I was driving out on some back roads when I found this problem. First I was crusing in a 60kph zone, then it goes to 100 and up a really steep hill. I was in third and it wasn't speeding up, so I put it in second, which was about 3800RPM, I put the pedal to the metal and got her upto 5000RPM. Then I get a huge power drop.. car starts t slow down, so I let the gas off, and put it back on, the more gas I give it the slower it goes, so I put it in 3rd, this is when 2nd was at about 3800RPM again, and it keeps dying (keep in mind I am still going up this steep hill.) So I gently get her up the hill in second at about 3000RPM and cruse behind a truck for a while. Then I give it gas and it seems fine again. Until I hit 5400RPM, this time in 3rd gear. Then it does the same dying thing. After about 20 to 30 seconds its back to normal.

Temp was fine. There might of been some pinging (I'm running 14degrees BTDC but only on 91octain) but that sound also might be something in my exhaust I think.

 

Could this be a fuel problem? Maybe the float chamber is getting empty? Could that be because my filter (haven't ever changed it, I got the car 19months ago. dunno if the previous owner did either.)

The fuel flow out the pipe in the hood looks fine.

 

Anyone had a similar experience?

 

I can rev her to 6000RPM in 1st gear to worries. Although she seems reluctant to go past that 6k barrier. Which is weird, because when I got the car it used to rev to 7K easy, and I once got to 8... but she wasn't too happy about that.

 

Thinking of all that, I also had some problems with my exhaust once. The cat was falling apart. I ended up losing power altogether once and had to creep along at 20kph in second gear.. After getting her to a friends place I rev'd the engine as much as I could and finally part of the cat went flying out the back! I have a 2" straight thru pipe. I really need to cut that cat out and just weld in a bit of pipe to replace it. I have pics of the honeycomb part that came out the cat. I'll have to post them.

 

Sorry about the long post.. lol

 

Thanks for any help.

[Turbone]

It sounds like thats your problem again. There is most likely pieces left in the cat and now they are blocking the exit.

When was the last time you changed your fuel filter?

[Phizinza]

But I wouldn't think it would make the engine run like &*^$ for half a minute after. I would of thought it would just not rev high, then once the RPM goes down it would be back to normal.?

[4x4_Welder]

If you build pressure in the exhaust at higher rpms, then it will take a little bit for it to go away. My vote goes to a plugged or semi-plugged fuel filter, though. It's a cheap fix, and couldn't hurt since you're supposed to change them every 12k miles, or annually IIRC.

 

Just out of curiousity, how much do you think it would cost to get one of those dual carb intakes here in the US?

Real power for an EA81 = and

[Phizinza]

Intake with carbs (needing rebuilds) costs about $350AUD. Plus about $80 for shippin. That makes $330USD.

But, my engine isn't much better then my brothers normal EA81 which was rebuilt only a few hundred miles ago. And, I also have the complete EA81dc, with the reverse (highflow) heads and different cam.

I think I should give this engine a real good clean up and rebuid sometime soon.

 

I was offered $1500 for my EA81dc from a subie wrecker... A normal EA81 goes for around $200... Not worth it in my opinion.

 

Well, my brothers got the mig now, and I have another piece of 2" pipe (fence post! lol) So I guess I'll change the filter, and see how it goes, then get rid of that cat. Updates to come later.

[Jerry DeMoss]

If you build pressure in the exhaust at higher rpms, then it will take a little bit for it to go away. My vote goes to a plugged or semi-plugged fuel filter, though. It's a cheap fix, and couldn't hurt since you're supposed to change them every 12k miles, or annually IIRC.

 

Just out of curiousity, how much do you think it would cost to get one of those dual carb intakes here in the US?

Real power for an EA81 = and

 

If you want a dual carb here in the u.s. let me know.I know of a few that are still available in oregon.I ended up buying some myself.The only thing that is hard and next to impossible to get is the dc filter box.Pm me and I will get you the address.

[Phizinza]

Replaced the fuel filter, hit 6K in second gear and was still climbing, but I didn't want to go much further until I fix my exhaust...

 

It's weird, because my brothers fiat x1/9 has the exact same symptoms but even adding a better filter and an additional electric fuel pump didn't fix it. But his not to fussed about it now as his putting a turbo efi 1.3L in it, silly webers..

[4x4_Welder]

Sounds like I shouldn't abandon my custom intake and efi plan, then. I may still find a way to drop one of my old Motorcraft 2150 2BBLs on it, though. 354cfm, anyone? Good for the nice low redline of about 8k?

[Phizinza]

I guess I can't really comment on the power of a well built dual carb with all new carbs and stuff.. I'm just saying my old used one isn't that great. And if you only had the manifolds and not the heads I can imagine it is just going to suck more fuel without much effect.