5.8 Liter 500 bhp Lexus (N/A)?

[Lextreme II]

Lowboost is on the money. Due to the MID and sleevings, the block actually is weaker. However, boosting would be a built 4.7 with massive boost.

 

[cowboy bebop]

I like it over the top. : ) I'm used to a GT47 88mm on a 3.0L motor, so twin GT35's/ GT40s' on a large cube motor would be right on the money.

 

[Lextreme II]

What if we increase compression ratio from 12.5:1. Do u think this 5.8 will reach 500 bhp?

5.8L with 12.5:1 Compression 493bhp and 457 tq
Power (HP)-1UZ-FE 5.8L + Dual 70mm TB + 12.5CR + 207-C + 1mm OS Valves + Porting (David).dyn
Torque (ft-lbs)-1UZ-FE 5.8L + Dual 70mm TB + 12.5CR + 207-C + 1mm OS Valves + Porting (David).dyn

 

[lowboost]

wow I was close!

 

[JDMfantasy]

I'm with Cowboy on doing things over the top. There's no replacement for displacement.

 

[Pro]

nothing like a boosted and manual (stick shift), long stroke, big cube motor.

just ask those guys running turbo big blocks with manual gearboxes in some of those drag tanks....ooooh they're SO much fun to drive.

 

[lowboost]

and they only drive them on the 1320 and then trailer it home... so I think Lex wants some driveablilty

jeff

 

[turboteener]

Titanium rods will not make any more HP than standard steel rods in a normal street application. Although your car will feel much faster because you just came of all the wieght of that money for the rods. IN a race application you can make more power by being able to rev the engine higher for a longer period of time.

I have a feeling there is so much power left on the table by the Toyota engineers in the design of the camshafts. There is no reason a properly built 4.0-4.5 litre engine can't make 400-450 NA street HP with proper modifications. You need to emphasize the important stuff. Get the air in and burn it more efficiently.

 

[turboteener]

I just though of something else. The Daytona Prototype engines:

LEXUS (TRD) 4.3L V8
Bore : 3.545″ Stroke: 3.300″
Minimum crank weight: 38 lbs
Maximum compression ratio: 11:1
Cylinder head intake runner maximum volume: 139 cc’s
Cylinder head exhaust runner maximum volume: 81 cc’s
Intake valve: 1.356″
Exhaust valve: 1.147″
Piston w/rings, pin and connecting rod: 1053 gm minimum
Maximum camshaft lift @ retainer with zero lash: .478″
Maximum cam duration: 260° @.050″ lift
Rons 4 hole throttle body with 1.875″ diameter butterflies.
Intake manifold TRD (as approved)
RPM limit: 8100
Maximum fuel pressure 5 bar ( 72.5 psi)

In reality these specs are not all that outrageous. The compression and camshafts could easily run on pump gas. In fact this whole motor could run on pump gas with the proper engine tuning. Would it be the greatest engine for a heavy street car like the LS400, No, but why build a high reving street motor for a 10K lb street car, anyway. For other lighter swaps it would be great.

In reality the big street cars that need torque downlow should look at a custom version of the Toyota supercharger kit. A roots or centrifugal supercharger would be the ticket for a quick street car. I would be much cheaper than going NA.

 

[Pro]

Titanium rods will not make any more HP than standard steel rods in a normal street application. Although your car will feel much faster because you just came of all the wieght of that money for the rods. IN a race application you can make more power by being able to rev the engine higher for a longer period of time..

very true. it's like the lightened flywheel situation.

the only way they "make power" is give your engine the ability to rev higher (and said power comes with that) and do so more reliably because of the lack of inertia.

 

[Pro]

i'm really interested in all this - i have my engine on a stand in my garage now after not being able to sell it and i keep thinking about stuff like this.

keep it all coming.

 

[Lextreme II]

The reason i dont think the 5.8L UZFE be FI is the picture below. The block is almost machined and leave little meat left.

 

[Matt Skinner]

Contrary to what everyone is saying about Ti rods etc, lightweight engine internals DO increase performance. Purely because its taking less power to accelerate the engine itself, more of the power it makes is available to accelerate the car. Though it wont actually produce any more power in the 1st place, less is lost while you are accelerating.

 

[turboteener]

The reduce rotating losses, correct, but in and of themselves they really don't free up that much HP. Unless you are running a carbon fibre driveshaft, aluminum, flywheel, lightened crank, gundrilled axles, manual transmission with straight through final drive, lightened rear gears, lightened hubs, and lightwieght wheels, you really will not see much of an improvement. There are many other things that you can put 2500$ towards before you need to worry about TI connecting rods.

 

[cowboy bebop]

I'll second that. In truth, the amount of HP the Ti rods free up may be the equivilent of turning up the boost another 1 - 2 psi.

Eric

 

[toad007]

Dude the camshact specs for that 5.8L engine are way mild. Look at the powerband. it peaks and dies off fast at 5000-5500. You gotta think, those cams are designed to be a good wild cams for a 4L v8 and you've just increased the displacement almost 50%!!! You need MUCH bigger cams. With a good rod/stroker ratio theres no reason that motor couldn't be revved to 7500-8000 in a street application. Better matched cams to the new displacement would probably easily make 600+hp. The toyota SCORE tundra made 600+ out of a 5.0L 1uzfe @8000 rpm with 13:1 compression ratio. They also said that the motor kept making power past 8000,but in race ap for durability they only rev to 8k. So the power potential is there.

 

[turboteener]

How did they get the 5.0 out of the 1UZ?

 

[Lextreme II]

I wonder if high compression ratio would affect the valves and wild cams. I think that could be a potential problem.

 

[toad007]

How did they get the 5.0 out of the 1UZ?

3.7"( might be slightly bigger than 3.7, like maybe 3.750 or something ) sleeves and a 3.5" stroke crank. The new motor they have for this years season is bigger with the same bore with a 3.75" stroke.

 

[Matt Skinner]

The reduce rotating losses, correct, but in and of themselves they really don't free up that much HP. Unless you are running a carbon fibre driveshaft, aluminum, flywheel, lightened crank, gundrilled axles, manual transmission with straight through final drive, lightened rear gears, lightened hubs, and lightwieght wheels, you really will not see much of an improvement. There are many other things that you can put 2500$ towards before you need to worry about TI connecting rods.

You'd be surprised at the difference lightweight innards make. David Vizard worked out that on my engine (nothing fancy, an Austin A series) every Lb you manage to save on the flywheel for example works out to feel like 17lbs off the car. When you knock about 10lbs off (perfectly possible) you really feel it(I can vouch for that). Ok its in a light car, but it DOES work. Obviously lighter rods and pistons are harder to calculate the difference but it all adds up!

Agree with you though that Ti rods = last thing on the list far cheaper to get a light flywheel, and as cowboy says, increase boost!