Con rod Bolts upgrade on 2F

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Trollhole said:
You would be better off shifting gears. There is not much torque and hp at 5k.
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Impossible to shift gears in the dunes . As soon as you hit the clutch to shift the car comes to a immediate stop and all momentum is lost .
You need high revs in the dunes .
But in principle I agree with Marshall - I feel uncomfortable above 3500 rpms .
 
I gotta agree... a 2F singing at 5000 is a beautiful thing. :)


Mark...
 
Yspen said:
Impossible to shift gears in the dunes . As soon as you hit the clutch to shift the car comes to a immediate stop and all momentum is lost .
You need high revs in the dunes .
But in principle I agree with Marshall - I feel uncomfortable above 3500 rpms .
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I have some experience in sand, but am not a core wheeler so take my advice with a grain of it; why not just run a cam that offers power +/- 500 rpm of 3500?
 
like it was said before sometimes the wheel speed required cant be made at 3500 RPM with or without a cam on these engine. and if the wheels speed is met it is quickly lost from not enough power to keep it goin.
 
This thread is about making short the bottom end survives at higher RPm. The only reason for that is if you are making power at higher RPM. The 2F CAN be built to do that. A few of us have done so. It works well. If you want to talk about stock engines not keeping up... sure, they don't... which is why..... we build them instead :)

Seat of the pants comparision... a tweaked 2F will pull through a boggy mudhole, spinning freely in second gear, where a stock engine would have to do in 1st gear to keep from bogging down in the same spot. BTDT. Second gear at 5000 or 1st at 3500... Much more better :)


Mark...
 
RockDoc said:
Yup.

Incidently, anyone know if the 3FE's computer has a rev limiter built in? Reading up on the Bosch systems it's based on, it seems some of them did. :hhmm:
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Yes it does. I've been told I'm smoking something funny for saying it, but my 1989 FJ62 definitely does and if you hold it there too long it will change to 'limp mode' and won't rev up at all until you let off.

I should video it just to prove it.
 
tonkota said:
Yes it does. I've been told I'm smoking something funny for saying it, but my 1989 FJ62 definitely does and if you hold it there too long it will change to 'limp mode' and won't rev up at all until you let off.

I should video it just to prove it.
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What RPM have you encounter this at? This is after you built the 2FE? It couldn't just be overtaxing the injectors duty-cycle, could it? If it does in fact have a rev limiter, :clap:
 
RockDoc said:
What RPM have you encounter this at? This is after you built the 2FE? It couldn't just be overtaxing the injectors duty-cycle, could it? If it does in fact have a rev limiter, :clap:
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I'll have to take a video. I'm pretty sure it limits at about 4500 RPM, but when it happens it cuts and then revs and then cuts, pulsing. If I keep my foot in it, it will die mostly, idling fine, but no more revving until I turn it off. This was with the 3F-E and the 2F-E. No difference.

This limiter is similar to the one present in the Saturn and my Pontiac.
 
Neat, I'll have to "look" myself if we are out snow-wheeling this winter.
 
ECUs generally don't care about duty cycle. Either they are programmed to provide a given duty cycle based on input (mass air/speed density, throttle angle, rpm...) or they aren't. They don't actually know that a given duty cycle is too high for conditions unless those conditions are way out of range (which generally represents as a sensor out of range error). If they had this type of logic it would be really hard (or maybe impossible) to compensate for things like altitude. This is how piggy back ECUs are able to slip in and modify behavior (for example influence injector duty cycle by modifying sensor inputs to the ECU).

As an aside based on stock flow rates for 3FE injectors you hit 80% duty cycle at ~190 crank hp. 100% duty cycle would fuel up to around 210-220 IIRC. At least based on the calculator at RC Engineering.
 
tonkota said:
I'll have to take a video. I'm pretty sure it limits at about 4500 RPM, but when it happens it cuts and then revs and then cuts, pulsing. If I keep my foot in it, it will die mostly, idling fine, but no more revving until I turn it off. This was with the 3F-E and the 2F-E. No difference.

This limiter is similar to the one present in the Saturn and my Pontiac.
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Sounds like something wrong with your ECU to me. I have taken 3 different 3FEs in FJ62s past 5000 a few times each. I have busted pistons in two different 3FEs taking them up around 5500. I do not push the 3F engines past 5000 any more. I have taken more past 4500. I set the upshift point at about 4500 usually when I adjust the kickdown cable on any 3FEI work on.
I have taken my daily driver FJ80 to about 4800.

Never encountered any sort of electronic rev limiter and I seriously doubt that there is one.


Mark...
 
Mark W said:
Sounds like something wrong with your ECU to me. I have taken 3 different 3FEs in FJ62s past 5000 a few times each. I have busted pistons in two different 3FEs taking them up around 5500. I do not push the 3F engines past 5000 any more. I have taken more past 4500. I set the upshift point at about 4500 usually when I adjust the kickdown cable on any 3FEI work on.
I have taken my daily driver FJ80 to about 4800.

Never encountered any sort of electronic rev limiter and I seriously doubt that there is one.

Mark...
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I feel bad about hijacking this rod-bolt thread. I'll copy and paste this discussion in a new one.
https://forum.ih8mud.com/60-series-...ontinued-rod-bolt-discussion.html#post4935525
 
Mark W said:
I have taken 3 different 3FEs in FJ62s past 5000 a few times each. I have busted pistons in two different 3FEs taking them up around 5500. I do not push the 3F engines past 5000 any more.

Mark...
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Dang short rod/stroke ratio. When I looked at (and quickly abadonded) trying to stroke a 3FE I thought that this was a 3FE quirk (some sort of money saving idea to simply destroke the 2F). Then I started noticing that Toyota doesn't seem to be the only OEM of that time period that experimented with short rod ratios (and here I'm defining short as shorter than a Chevy small block, which really isn't all that long).
 
I think in this case it was all about reducing the over all height of the engine. since the EFI sits up pretty high on top of the head and the hood line was low... they wanted to save space somewhere. Shrinking the block was the easy answer and the rods shortened up to match. The 3F is not a terrible motor. But the 2FE is the motor that Toyota should have made instead. Figure out another way to keep it under the hood. Enthusiasts are managing to do it just fine.


Mark...
 
From the dyno runs I have done with my 2f with the rv cam the max torque is around 2400 rpms. Max HP is around 3600. After that it fall like a rock at 4200 rpms for hp and around 3600 for torque.

Would be interesting to see what a stock cam would look like. I'm betting the numbers would be better.

My question is wouldn't it be better to stay within the max torque/hp numbers?

I understand for sand that may not be possible.
 
Marshall , FWIW I have decided not to increase duration and lift in the cam . It is going to a cam grinder that is going to make the torque curve come in a bit later but it will last over a longer rpm band - or that is how he explained it to me .
It is a bit of a compromise but how I prefer it .

The ARP bolts for a Supra has been ordered ( so my question has been answered ) . That is probably overkill in my case - but it is a rebuild and I want to get the best stuff in there .

We are planning a dyno day for our local club in Cape Town - I will post stock 2F and 3F ( carb ) figures in the Camshaft thread ( the one started by Tonkota ) when I get them
 
RockDoc said:
Incidently, anyone know if the 3FE's computer has a rev limiter built in? Reading up on the Bosch systems it's based on, it seems some of them did. :hhmm:
Click to expand...

tonkota said:
Yes it does. I've been told I'm smoking something funny for saying it, but my 1989 FJ62 definitely does and if you hold it there too long it will change to 'limp mode' and won't rev up at all until you let off.
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Aaron is correct. Directly from the 1988 Model New Car Features, Land Cruiser, page 138 -

"8b. Fuel Cut-off Due to High Engine Speed. To prevent engine over-run, fuel injection is cut if engine speed rises above 5000rpm. Fuel injection is resumed when the engine speed falls below this value."
 
pappy said:
Aaron is correct. Directly from the 1988 Model New Car Features, Land Cruiser, page 138 -

"8b. Fuel Cut-off Due to High Engine Speed. To prevent engine over-run, fuel injection is cut if engine speed rises above 5000rpm. Fuel injection is resumed when the engine speed falls below this value."
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I need to print this and hang it on the refrigerator for the wife to see :D


Thanks!!!!
 
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