FJ80 4.0L power improvement??? (2 Viewers)

[pkorrupted]

I have a 1991 Land Cruiser. It has the under powered 3F-E 4.0L strait 6. I just went trough and tuned it up (plug, wires, cap, rotor, fuel filter, timed it, and changed every fluid in the vehicle). It has 140-150 psi across all cylinders on the compression test and 60psi for fuel pressure at the rail. The truck has 141,XXX miles on it. I also put a K&N air filter in. This made the truck run MUCH better but still way under powered for how large the vehicle is. I was thinking about hollowing the cats and changing the muffler, I really don't want to make it loud but that is the only other thing I can think of since there are no after market performance parts available. Any suggestions for more power?

 

[Hilux]

yay!!! Another power thread!! Another owner disgruntled about the output of their engine!

This made the truck run MUCH better but still way under powered for how large the vehicle is.

Easy fix! Get a smaller vehicle? It's basic physics... Lighter vehicle, more power and MPG. B/c less mechanical force is needed to propel the vehicle.

 

[RockDoc]

Make sure your throttle cable and transmission throttle cable are adjusted decently. If it's upshifting before say 3600 rpm on hard throttle, you aren't getting the most out of the engine. You can advance the timing a bit, and keep an ear out for rattling to make sure you haven't gone too far. The intake gets gummy on these guys....

Mine had no cats when I got it, not sure how much difference that made..... Swapping out the original muffler really opened up the top end for mine. Prior to that, it didn't seem to pull hard past say 3200 rpm, now it runs strong to 4000 rpm and beyond.

 

[Nay]

Sure, swap in a V8.

The mods you are talking about are like buying better shoes for a fat chick to run a marathon.

 

[RockDoc]

Sure, swap in a V8.

The mods you are talking about are like buying better shoes for a fat chick to run a marathon.

Speaking of which, what size tires are on it? Bigger isn't always better if you are looking for something that can get up and go on-road. But then, nobody wants to run smaller tires now, do they?

 

[lt1fire]

Adjust the kick down cable
Put a large exhaust system in it with better cats and muffler


That is really all you can do

Re-gear

 

[CJF]

Another vote for adjusting the kickdown cable.

Sounds silly, but it really does make it feel like a completely different vehicle.

 

[mshelby]

Or just do what everyone else has done, myself included....learn to appreciate how much power the engine actually has and not worry about 0-60 times.

 

[spdwaver]

Or just do what everyone else has done, myself included....learn to appreciate how much power the engine actually has and not worry about 0-60 times.

Or, buy a 1993-1997 (and I quote) "powered by the vastly superior flipoff2: ) 1FZ-FE engine."

I tried the de-smog, had after market exhaust - nothing changed the venerable 3F-E's power; neither up or down, regardless of extra weight or lack thereof.

That is what I did after my '91 was wrecked, and noticed a huge increase in throttle response. Because the 1FZ-FE had so much power, I changed the tires to a 315 to slow her down.

 

[jonheld]

When was the last time the valves were adjusted?

Hollowing out the cats is simply stupid IMO. They can be replaced and are probably due after 19 years.

The emissions system and vacuum system will have effects also. Make sure they're performing properly.

The fuel injectors will most lilkey need to be serviced as well.

Try approaching your motor not from the standpoint of power, but more from the standpoint of it's 19 years old. Fix what's broke first. It will never be a rocket ship, but it will run forever.

 

[mshelby]

Or, buy a 1993-1997 (and I quote) "powered by the vastly superior flipoff2: ) 1FZ-FE engine."

I tried the de-smog, had after market exhaust - nothing changed the venerable 3F-E's power; neither up or down, regardless of extra weight or lack thereof.

That is what I did after my '91 was wrecked, and noticed a huge increase in throttle response. Because the 1FZ-FE had so much power, I changed the tires to a 315 to slow her down.

Blah blah blah

At least the 3F-E is consistently sluggish regardless of the weight lol. I did see a slight increase when I desmogged but not enough to blow my mind.

After going up a few sizes in tires I am starting to feel the potential need to re-gear but right now I am going to stick with it and see if I can just get used to it.

Still want to do the diesel conversion but that has been put on hold for the time being.

 

[jlg32281]

Sell it and buy a sports car.

 

[Eicca]

It's a tank. Get used to it The 3FE is an engine designed for torque, not speed. Do all the maintenance of course, but beyond that, save your money.

 

[spdwaver]

Blah blah blah

At least the 3F-E is consistently sluggish regardless of the weight lol. I did see a slight increase when I desmogged but not enough to blow my mind.

After going up a few sizes in tires I am starting to feel the potential need to re-gear but right now I am going to stick with it and see if I can just get used to it.

Still want to do the diesel conversion but that has been put on hold for the time being.

I know this may seem unlikely, but if I still had my '91, I would not want to change the motor. It's that good, in the way of reliability and dependability. I [inadvertently] tried to kill it, but was unsuccessful in doing so. Keep up the maintenance, feed it gas and oil, and it will go on and on.

Jon Held's website (JH Home) offers some lesser known insight to the 3F-E (such as the fuel filter in the tank), to help it perform at it's best.

On-road performance may have been less than desirable, but overall the engine (mine was at 242,000 miles) was true, regardless of how much extra cargo, bumpers, passengers or the like, were on board.

Off-road performance was where it really shined, and I do miss it.

 

[mshelby]

I know this may seem unlikely, but if I still had my '91, I would not want to change the motor. It's that good, in the way of reliability and dependability. I [inadvertently] tried to kill it, but was unsuccessful in doing so. Keep up the maintenance, feed it gas and oil, and it will go on and on.

Jon Held's website (JH Home) offers some lesser known insight to the 3F-E (such as the fuel filter in the tank), to help it perform at it's best.

On-road performance may have been less than desirable, but overall the engine (mine was at 242,000 miles) was true, regardless of how much extra cargo, bumpers, passengers or the like, were on board.

Off-road performance was where it really shined, and I do miss it.

When I first got it I immediately wanted to replace the 3F-E with a 350 but after driving it for the past 4 months I have built an appreciation for this sleeping beast.

Mine is at 330k and other than a leak from the valve cover gaskets (I think and replacing it tomorrow) there is no signs of any wear on it.

Toyota built a tank and gave it an engine that is just as tough as the chassis it sits in.

 

[Hilux]

Nobody said adjust the base timing (mod) and 2Fe...


But I guess with a power post every 5 minutes, some things tend to slip between the cracks...

When will you guys learn the 3Fe is a de-stroked 2F. I'm sure Toyota did that b/c the 2F was too stroked and in a non overdrive transmission. But neglected to discover they didn't need to in an overdrive transmission.

All Toyota manual trannys that I know of had a 250rpm drop IF they had an overdrive.

ALL Toyota AUTOMATICS had a 500rpm drop into overdrive...

Clearly you DO NOT need a de-stroked motor if your overdrive is deep enough...

Chiltons repair manual, for 70-88 trucks says the 2F has:

...............2f.... 125hp @ 3600rpms and 200 ft/lbs torque at 1800rpm.

Now the 3Fe... 154hp @ 4500rpms and 220 ft/ lbs torque at 3000rpms... see the difference?

Now take the 22R and Re... Both are identical motors except for the EFI.

22R is 96hp @ 4800 and 129 ft/ lbs @ 2800rpm
22RE 116hp @ 4800 and 140 ft/ lbs at 2800rpm...

So take the % in power difference, divide that by 4 and you get a % gain that EFI ALONE, makes PER-Cylinder. Now multiply that by 6 and add that to the 2F's power and see what you get.

That SHOULD be the theoretical improvement EFI ALONE makes to a 2F engine...

 

[Lka1988]

I love my 3FE. Next engine going in after it blows will be either a 383 or Cummins 6BT.

 

[pkorrupted]

It has the stock 31" tires, valves were adjusted yesterday (intake lash .008 and exhaust lash .014) per manual. This is a really good engine and I do not want to swap it or drag race it, I figured if I freed up some pony's it would equate to better mileage as well. Im going to hollow the cats and put a different muffler on and then advance the timing and see where im at for power. Any other ideas please shoot them at me.

 

[RockDoc]

Again, make sure that the throttle cables are adjusted right, that will give you the biggest improvement. (unless they already are proper)

 

[64galaxiemann]

JET CHIP

Anyone try a jet chip?..I have a 91 fj80 and was thinking about it..