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Discussion Starter #1
Please tell me how we can get more low end torque out of our FJ's , what mods do I have to do ?
Thanks
 

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Cold Air Intake, Iridium Spark Plugs, Super Charger. Cold Ait Intake will make a huge differance. Exhaust will add high end
 

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The ways to get more low-end torque out of any four-stroke gasoline engine are thus, in order of biggest impact to least:

1. Increase the stroke. This is by far the most effective. Every good torque motor is under-square, i.e. the stroke is longer than the diameter of the bore. The "F" series engines in 25, 40, and 60-series Land Cruisers are good examples. Nothing can replace more leverage on the crankshaft that you get with longer stroke.

2. Camshaft(s) with long exhaust duration.

3. Moderate to small exhaust valve size and header/exhaust tubing size; gives better scavenging at low rpm's.

4. Bumping the compression; doesn't technically increase torque, but it will increase HP across the entire power band including low rpm.

The problem is, none of these things are practical for the 1GR-FE. And even if you had a bottomless bank account and could build a one-off motor with all these things, you would lose your high-end rpm's and HP. That's one reason why early Land Cruisers are so slow on the highway and get hideous gas mileage. To sell more of them to more people, Toyota had to tune the engines over time to be better highway engines, at the expense of low-end torque. In a 4-stroke gasoline engine, you just can't have your cake and eat it too.
 

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Discussion Starter #4
thank u so much for that info it was really good info , just one more thing, would a unichip help any , as more power , dose that mean more torque ?
thanks again
 

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thank u so much for that info it was really good info , just one more thing, would a unichip help any , as more power , dose that mean more torque ?
thanks again
Sorry, I'm too old to know anything useful about chips; to quote Mark Algazy, I'm "a carbureted man in a fuel injected world". :)

But it seems to me that most of them are tuned for high hp at high rpm, which is the exact opposite of what you're trying to do, and will in fact hurt your low-end torque, so be very careful and do your homework (more than just manufacturer's claims) before you buy and install a chip.

You understand that HP = torque x RPM, so no, more hp does not necessarily mean more torque, it just means that the faster you can spin a given engine the more hp it will make. That's why these chips are tuned for high rpm, because that's where the big hp numbers are, and big hp numbers are what sells stuff to (mostly uninformed) customers. The fact that most people other than drag racers will never see those high rpm ranges in any street driving (never mind a 4WD trail...) does not deter buyers from being wowed by the high hp claims and buying them.
 

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The following 2 items won't change your engine torque a bit but it will 'feel' as if it has more torque. a.) go to a smaller diameter tire b.) change your gear sets to a higher ratio.

DEWFPO
 

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The following 2 items won't change your engine torque a bit but it will 'feel' as if it has more torque. a.) go to a smaller diameter tire b.) change your gear sets to a higher ratio.
Good points. You're right, they won't change the engine torque, but they will increase the wheels torque to the ground, which is still beneficial.
 

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Discussion Starter #8
Sorry, I'm too old to know anything useful about chips; to quote Mark Algazy, I'm "a carbureted man in a fuel injected world". :)

But it seems to me that most of them are tuned for high hp at high rpm, which is the exact opposite of what you're trying to do, and will in fact hurt your low-end torque, so be very careful and do your homework (more than just manufacturer's claims) before you buy and install a chip.

You understand that HP = torque x RPM, so no, more hp does not necessarily mean more torque, it just means that the faster you can spin a given engine the more hp it will make. That's why these chips are tuned for high rpm, because that's where the big hp numbers are, and big hp numbers are what sells stuff to (mostly uninformed) customers. The fact that most people other than drag racers will never see those high rpm ranges in any street driving (never mind a 4WD trail...) does not deter buyers from being wowed by the high hp claims and buying them.
Thank guys , this is what I'm doing is home work ,, all this is very help full and you all get a A for your help :rocker:
 

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Discussion Starter #11
Out of pure curiosity why are you trying to improve low end torque? Towing?
there is some really big hills around here that u just want to creep up at a slow speed, but as I see it now I will just kept putting it in 4LOW,
 

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this apparently seems to be a big trouble for offroaders with the new 2010 engine and upwards....

after seeing the dyno charts from the older engines and the new ones - there is a huge difference in low end torque

the previous engine chart from 1000 rpm to 3500 rpm looks like a straight line drawn from 8 clock to 12 clock

at these same rpm the new engine charts show a 8 clock to 3 clock line....

we tried everything external - unichip, headers, air intake and catback - tried mixing and matching stock and performance parts

low end torque is crucial for dune bashing as you need to slow down verify the next dune and surroundings and then pedal as required.

tires are michelins on 10 psi..... best for sand...

if there is a run up and once you reach 3000 rpm the new 2010 engines are amasing - and more powerful than the older engine

but without small runups - its a dead leaf

somehow no on seems to have a satisfiable solution.

ring and pinion was suggested by there is draw back on highway the rpm stays very high....

any inputs will be appreciated gentlemen.

thanks.
 

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I think with the 2010 and up FJ it required driving in 4L when hitting those nice huge dunes in Liwa or elsewhere in the UAE.

Try running up a dune face in 4L and third gear and you can shift to second if you feel power loss...you will be surprised where your 2011 will tkae you in 4L.

I used to have a 2008 and now drive a 2010 and the driving charecterstics of both are totally different in off road (desert) driving.
 

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after seeing the dyno charts from the older engines and the new ones - there is a huge difference in low end torque
I've never seen these charts. Can you post them or links to them ?

Typically, most V4 or V6 engines will not have great low-end torque unless specifically engineered for that purpose (see 1911's post) or built as a diesel.

My first pickup truck, a 1993 Ford F150 (2wd) with 300 straight six has forever spoiled me. While not a fast revving tire smoker, the low end lugging power of the engine was very impressive and is only matched by current V6 or V8 pickups if they kick down into a lower gear and spin up to a much higher rpm.
 

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I think with the 2010 and up FJ it required driving in 4L when hitting those nice huge dunes in Liwa or elsewhere in the UAE.

Try running up a dune face in 4L and third gear and you can shift to second if you feel power loss...you will be surprised where your 2011 will tkae you in 4L.

I used to have a 2008 and now drive a 2010 and the driving charecterstics of both are totally different in off road (desert) driving.
Thanks Ahmed fo rthis tip. I am going to try it out this weekend in the desert. :rocker:
 

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well as for an opinion on gaining torque for the engine is do one thing first of all , go buy urself an electric fan instead of the OEM u have on ur rig , cause the fan on a FJ cruiser is a clutch fan that spins upon rpm. u will find different electric fans : two molded fans in one frame instead of one either and u will save alot of torque that was lost with OEM FAN

and a torque converter will do also if u have an AT , but shifting between gears will be a bit harsh and not smooth as OEM =)
 
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