Tacoma 4.0 engine swap?
#21
Contributing Member
This is actually not true.
Octane ratings only address the fuel's resistance to detonation, nothing else. The flame front and energy density are not affected unless the higher octane fuel is formulated differently which it often is to improve energy density.
Sometimes manufacturers dope the fuel with more carbon-carbon bonded molecules which take a high activation energy to break up (thus resist detonation) and also therefore release more energy per unit volume.
Octane ratings only address the fuel's resistance to detonation, nothing else. The flame front and energy density are not affected unless the higher octane fuel is formulated differently which it often is to improve energy density.
Sometimes manufacturers dope the fuel with more carbon-carbon bonded molecules which take a high activation energy to break up (thus resist detonation) and also therefore release more energy per unit volume.
The fact that the engine can run at a high compression ratio in itself improves the engine's thermodynamic efficiency.
To save money, one might run the lowest octane fuel, I do. However, my engine is not designed to take advantage of the higher octane hence my savings.
To save money, one might run the lowest octane fuel, I do. However, my engine is not designed to take advantage of the higher octane hence my savings.
#22
If you can shoehorn that 4.0 into a 2nd gen, I bet you will be getting over 20 MPG.
I am getting 19.60 MPG with 1" over stock size mud tires (I am running 285x70x17, stock is 265x70x17) 3" lift, heavy bumper/winch combo city/freeway combined driving.
The rig also is pushing I bet around 4.6K lb or better.
I am getting 19.60 MPG with 1" over stock size mud tires (I am running 285x70x17, stock is 265x70x17) 3" lift, heavy bumper/winch combo city/freeway combined driving.
The rig also is pushing I bet around 4.6K lb or better.
#23
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A few guys running premium in their 4.0's are reporting that they are noticing better gas mileage running premium over regular. If your engine can benefit from running premium, I say take advantage of it.
Fuel is mainly comprised of Octane and Septane. Octane is a more complex molecule which can handle compression better. Septane is more unstable so it readily ignites when compressed. Thus the more Octane, the more stable the fuel is, and the more it can resist compression before detonation.
Now putting this all together - the more you can compress a fuel without it igniting from the compression (you want the spark to cause it to ignite as that's what works best with your timing chain/timing belts and the stroke of the piston), the more power it has/the harder it blows the Piston back which equals power/torque when the spark ignites. An engine with a higher compression ratio, combined with fuel that can tolerate this higher compression ratio, equals an engine that doesn't have to work as hard, and has a bit more power as well.
Fuel is mainly comprised of Octane and Septane. Octane is a more complex molecule which can handle compression better. Septane is more unstable so it readily ignites when compressed. Thus the more Octane, the more stable the fuel is, and the more it can resist compression before detonation.
Now putting this all together - the more you can compress a fuel without it igniting from the compression (you want the spark to cause it to ignite as that's what works best with your timing chain/timing belts and the stroke of the piston), the more power it has/the harder it blows the Piston back which equals power/torque when the spark ignites. An engine with a higher compression ratio, combined with fuel that can tolerate this higher compression ratio, equals an engine that doesn't have to work as hard, and has a bit more power as well.
#26
Registered User
Why not 'clip' it?
By that I mean, buy a rollover of the motor/driveline you want, take it to a frame shop and have them straighten it if need be and do any needed repairs to the front end.
Then find an area where the two frames coincide and cut out your 90s stuff and insert the whole modern frame, IFS, steering, etc. Customize the radiator support as need be for cooling and hook up the steering. If I went this far, I'd choose a Limited 4Runner as the donor vehicle so I could get the auto climate control, new seats and the whole 9 yards and update the interior too. You might as well use the rear end too so you have 4 wheel disk and ABS.
You'd basically get all the modern conveniences at a fraction of the price and tax value (for those of you who pay taxes on your trucks every year.)
If you look at it like you are updating that much the cost of the donor vehicle isn't that great.
I'm just trying to decide to what to do this with, Tundra w/ the 5.7, 4Runner w/ 4.0 or some LS1 kind of animal.
I'm sort of hoping the planets don't align until there's a plug in hybrid drivetrain I can put in. Like maybe from a plug in hybrid Tundra maybe
That's what I'll do.
By that I mean, buy a rollover of the motor/driveline you want, take it to a frame shop and have them straighten it if need be and do any needed repairs to the front end.
Then find an area where the two frames coincide and cut out your 90s stuff and insert the whole modern frame, IFS, steering, etc. Customize the radiator support as need be for cooling and hook up the steering. If I went this far, I'd choose a Limited 4Runner as the donor vehicle so I could get the auto climate control, new seats and the whole 9 yards and update the interior too. You might as well use the rear end too so you have 4 wheel disk and ABS.
You'd basically get all the modern conveniences at a fraction of the price and tax value (for those of you who pay taxes on your trucks every year.)
If you look at it like you are updating that much the cost of the donor vehicle isn't that great.
I'm just trying to decide to what to do this with, Tundra w/ the 5.7, 4Runner w/ 4.0 or some LS1 kind of animal.
I'm sort of hoping the planets don't align until there's a plug in hybrid drivetrain I can put in. Like maybe from a plug in hybrid Tundra maybe
That's what I'll do.
Last edited by MonsterMaxx; 04-06-2008 at 02:47 PM.
#27
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Why not 'clip' it?
By that I mean, buy a rollover of the motor/driveline you want, take it to a frame shop and have them straighten it if need be and do any needed repairs to the front end.
Then find an area where the two frames coincide and cut out your 90s stuff and insert the whole modern frame, IFS, steering, etc. Customize the radiator support as need be for cooling and hook up the steering. If I went this far, I'd choose a Limited 4Runner as the donor vehicle so I could get the auto climate control, new seats and the whole 9 yards and update the interior too. You might as well use the rear end too so you have 4 wheel disk and ABS.
You'd basically get all the modern conveniences at a fraction of the price and tax value (for those of you who pay taxes on your trucks every year.)
If you look at it like you are updating that much the cost of the donor vehicle isn't that great.
I'm just trying to decide to what to do this with, Tundra w/ the 5.7, 4Runner w/ 4.0 or some LS1 kind of animal.
I'm sort of hoping the planets don't align until there's a plug in hybrid drivetrain I can put in. Like maybe from a plug in hybrid Tundra maybe
That's what I'll do.
By that I mean, buy a rollover of the motor/driveline you want, take it to a frame shop and have them straighten it if need be and do any needed repairs to the front end.
Then find an area where the two frames coincide and cut out your 90s stuff and insert the whole modern frame, IFS, steering, etc. Customize the radiator support as need be for cooling and hook up the steering. If I went this far, I'd choose a Limited 4Runner as the donor vehicle so I could get the auto climate control, new seats and the whole 9 yards and update the interior too. You might as well use the rear end too so you have 4 wheel disk and ABS.
You'd basically get all the modern conveniences at a fraction of the price and tax value (for those of you who pay taxes on your trucks every year.)
If you look at it like you are updating that much the cost of the donor vehicle isn't that great.
I'm just trying to decide to what to do this with, Tundra w/ the 5.7, 4Runner w/ 4.0 or some LS1 kind of animal.
I'm sort of hoping the planets don't align until there's a plug in hybrid drivetrain I can put in. Like maybe from a plug in hybrid Tundra maybe
That's what I'll do.
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#32
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by running higher octane your motor will run more efficent which in the long run you do get better gas mileage in most vehicals , in most case dealers require to run higher octane gas for warranty purposes . valve predetination is bad on valve train caused by low octane fuel runnin leaner than is called for . "burnt valves, burnt pistons" and dirter oil than normal
#33
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by running higher octane your motor will run more efficent which in the long run you do get better gas mileage in most vehicals , in most case dealers require to run higher octane gas for warranty purposes . valve predetination is bad on valve train caused by low octane fuel runnin leaner than is called for . "burnt valves, burnt pistons" and dirter oil than normal
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