4Cruisers
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If I'm not mistaken, the 3FE ignition timing is controlled by the ECU - no mechanical or vacuum advance hardware inside.
Fixing over compression on a 2FE (Camshaft analysis?) (3 Viewers)
- Thread starter ChaserFJ60
- Start date
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- Thread starter
- #42
Thats right, One plug going into the dizzy.
cps432
SILVER Star
For what it’s worth, my fj60 owners manual says to use 91 octane or higher. I think it says you can use 87 in a pinch. I used 85 for years until I read the manual. Now I use 91 exclusively and it has helped a ton with keeping things smooth. My valve train is really noisy though... I think it’s time for a rebuild...
So this could be detonation because of too much compression. High compression causes excess heat that detonates the A/F before the spark plug fires. I hope this isn't the problem.
- Thread starter
- #45
Well its true. Driving a classic Toyota Land Cruiser just got Even More expensive to drive.
This is based off of my FJ60 manual so I can imagine the FJ62 would be the same.
Even with the Octane booster I had the same issues but who can say how much it actually bumped up my gasses octane rating. Ill post back if it helped after my next premium fill up.
around here (New England) the lowest octane you can get is 87...which is what your manual is pointing to.Well its true. Driving a classic Toyota Land Cruiser just got Even More expensive to drive.
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This is based off of my FJ60 manual so I can imagine the FJ62 would be the same.
Even with the Octane booster I had the same issues but who can say how much it actually bumped up my gasses octane rating. Ill post back if it helped after my next premium fill up.
The rating will change at high(er) altitudes
The manual is showing two different Octane ratings. One is for the USA and the other is for the rest of the world. They're not interchangeable.
Research Octane No. is not the same as Octane Rating.
www.quora.com
In the USA, the factory recommend Octane Rating for a new 2F was 87 (regular gas).
Personally I found that my 2F got better performance and mileage running on mid grade Octane 89 (USA rating).
Running premium fuel I saw no improvement over mid grade.
Research Octane No. is not the same as Octane Rating.
Is "octane rating 87" the same as "Research Octane Number 91"? My vehicle's owner's manual says to "Select octane rating 87 (Research Oct...
Answer (1 of 6): The 87 listed is the average of research octane and motor octane ratings, commonly referred to as (R+M)/2. The 91 is research octane. They are approximately the same, depending on the actual compounds in the fuel. Research octane is normally 8–12 numbers higher than motor octane...
In the USA, the factory recommend Octane Rating for a new 2F was 87 (regular gas).
Personally I found that my 2F got better performance and mileage running on mid grade Octane 89 (USA rating).
Running premium fuel I saw no improvement over mid grade.
In my 60 have run 87 octane for about 100k mi, and 93 octane for 100k mi plus.
i think the 93 pays for itself in mileage alone,( in my truck) and is about like cutting the cat off performance wise.
. I get 15 mpg consistently on 93 Octane, 12.5-13.5 mpg on 87 octane.
In my 62 I can’t tell one bit of difference between 87 and 93 performance wise, maybe one mpg better on 93.
To all the folks here dwelling on the number of degrees of timing they are running, Remember each engine likes something different. The machining tolerances themselves on crank gear and cam gear, can stack up and leave one engine two or more degrees different than the next. Also crankshaft gear key way can be off. If you think Toyota put all engines on true TDC with indicator, then checked the bb and pointer on flywheel and bellhousing for perfection you are mistaken. Are they close, yes but not perfect. I’ve seen some off a good bit.
Just like you are at the track. Drive, turn distributor, repeat, repeat, etc... When you have it running at best performance without pinging, check your idle if it’s ok you are done. the timing light is just for your own personal reference when doing the above process. Again, don’t get hung up on timing light numbers.
i think the 93 pays for itself in mileage alone,( in my truck) and is about like cutting the cat off performance wise.
. I get 15 mpg consistently on 93 Octane, 12.5-13.5 mpg on 87 octane.In my 62 I can’t tell one bit of difference between 87 and 93 performance wise, maybe one mpg better on 93.
To all the folks here dwelling on the number of degrees of timing they are running, Remember each engine likes something different. The machining tolerances themselves on crank gear and cam gear, can stack up and leave one engine two or more degrees different than the next. Also crankshaft gear key way can be off. If you think Toyota put all engines on true TDC with indicator, then checked the bb and pointer on flywheel and bellhousing for perfection you are mistaken. Are they close, yes but not perfect. I’ve seen some off a good bit.
Just like you are at the track. Drive, turn distributor, repeat, repeat, etc... When you have it running at best performance without pinging, check your idle if it’s ok you are done. the timing light is just for your own personal reference when doing the above process. Again, don’t get hung up on timing light numbers.
- Thread starter
- #49
I cant win, When I have the dizzy set back I get a really rough cold idle, and the engine still pings when at operating temp. Im pulling my hair out at this.
I suspect your compression ratio is too high. Putting a 3FE head on a 2F already raises compression. Your machinist compounded that issue by milling the head and the block.
Try draining the tank and filling it with 93 octane.
Try draining the tank and filling it with 93 octane.
Do a compression test with the motor as warm as you can tolerate. If it’s over 175psi definitely need 93 octane.
Another option, get 5 gal can of race fuel and try it. If it runs good, compression is definitely too high.
Worse case scenario, you’ll need to run two head gaskets
Another option, get 5 gal can of race fuel and try it. If it runs good, compression is definitely too high.
Worse case scenario, you’ll need to run two head gaskets
- Thread starter
- #53
When installed max compression was 178psi. Its not just the Dizzy timing thats wrong here. I have a lowish vaccuum reading just below 15hg. My BVSV valve isnt operating correctly. My intake hose is cracked everywere and my rubber vacuum plugs are cracking. And I possibly have a faulty injector as with a borescope i found one to be particularly loud. Like I said this issue had been going on for a while, but with the summer temps here its just more prevalent.
Ok, you may have a lean condition you need to address first. Get a AFR gauge and check air fuel ratio. You’ll Have to weld a bung in exhaust Pipe.
178psi with stock cam is gonna put you between 9.5:1 and 10:1 static compression ratio which is very high for these motors.
Do you remember if the pistons had a dome or were flattop?
May need to go with some colder range spark plugs, along with working out the issues you know you have already
178psi with stock cam is gonna put you between 9.5:1 and 10:1 static compression ratio which is very high for these motors.
Do you remember if the pistons had a dome or were flattop?
May need to go with some colder range spark plugs, along with working out the issues you know you have already
- Thread starter
- #55
Flattop pistons, This issue only occurs when its 95F+ outside. this may be a perfect excuse for a snorkle. How does one do a "Cold Range sparkplug"
I'm big on the simplest answer that explains the issue is most likely. It sounds as if you had the head and block shaved and with the 3fe head, now your compression is too high and when you turn back the timing to stop the ping, your advance is off and it starts poorly cold...
... I'v never owned a 3fe, but I assume it's impossible to recurve. if so, maybe you can get the "shave" back with a thicker head gasket and run 91. Who knows, it may not do much, or maybe the motor will sing. If this is just a DD and you're gettin' broker from school I'd try that before something expensive like pistons (dished or melted).
... I'v never owned a 3fe, but I assume it's impossible to recurve. if so, maybe you can get the "shave" back with a thicker head gasket and run 91. Who knows, it may not do much, or maybe the motor will sing. If this is just a DD and you're gettin' broker from school I'd try that before something expensive like pistons (dished or melted).
If it comes down to reworking the internals you can have offset piston pin bushings made that drop the piston slightly…probably the least invasive modification but still requires the pistons to come out…though this can be done with the head off and block still in the truck.
before that though you could try running some colder plugs.
before that though you could try running some colder plugs.
- Thread starter
- #58
I love it when problems are this easy to find.
Update : after a temporary fix with ducttape it started right up and idle shot up to 1k instead of its set 650.
Update : after a temporary fix with ducttape it started right up and idle shot up to 1k instead of its set 650.
Last edited:
- Thread starter
- #59
Update 2:
Vacuum is now sitting at 18-20Hg, idle is smooth both at cool and warm temps.
Backfiring at deceleration has almost been completely omitted.
Ive heard the engine do its little pinging or knocking noise a few times at 2nd and 3rd gear but Ive had a hard time replicating it, i like to think the ECU is still learning. I'm going to let the ECU "relearn" for a few cold start to fully warm cycles before I touch the distributor again.
I'm pretty turned off to the whole tearing down my engine thing again for 3 main reasons
1. I have no money
2. It ran fine before I touched the dizzy and changed the air filter. It rarely did this on long road trips before and that was at 87 octane fuel.
3. Im now a full time college student and have no time to do a project that big again.
Vacuum is now sitting at 18-20Hg, idle is smooth both at cool and warm temps.
Backfiring at deceleration has almost been completely omitted.
Ive heard the engine do its little pinging or knocking noise a few times at 2nd and 3rd gear but Ive had a hard time replicating it, i like to think the ECU is still learning. I'm going to let the ECU "relearn" for a few cold start to fully warm cycles before I touch the distributor again.
I'm pretty turned off to the whole tearing down my engine thing again for 3 main reasons
1. I have no money
2. It ran fine before I touched the dizzy and changed the air filter. It rarely did this on long road trips before and that was at 87 octane fuel.
3. Im now a full time college student and have no time to do a project that big again.
Maybe you got it fixed. It’s always the little stuff. We like to go down rabbit holes here ( it’s easy to tear an engine apart behind a keyboard)
I personally would run 93 octane with your compression. Pre detonation kills main and rod bearings along with crank journals
Totally understand no money, and it being a daily driver. Ask Santa for a set of new injectors they might really pep it up!
I personally would run 93 octane with your compression. Pre detonation kills main and rod bearings along with crank journals
Totally understand no money, and it being a daily driver. Ask Santa for a set of new injectors they might really pep it up!
