07 4.7 Performance?

[bwingnutt]

Whats it take to get 400bhp out of the 4.7 in my 4Runner.We have read the weakness in the stock rods and mains. Thanks for any replies

 

[stevechumo]

Whats it take to get 400bhp out of the 4.7 in my 4Runner.We have read the weakness in the stock rods and mains. Thanks for any replies

The stock engine has around 285 bhp, so it has a good foundation to create more hp. If your concern is week rods, then a set of cams, complete exhaust system, cold air intake system, piggyback or standalone ECU, and tuning will net in it 400 bhp respectively.

 

[JBrady]

You are starting with 260hp @ 5400rpm with 10-1 compression and a 5700rpm redline. 400hp is a gain of 132hp or roughly a 50% gain in power. This will take big dollars and major changes to reach on engine alone.

With a 7000rpm redline the new 5.0 mustang coyote engine makes 412hp (82.4hp/ltr) at 6500rpm with 11-1 compression and vvt on both cams. That is You are trying to make 400hp with 4.7 liters (85.1hp/ltr) with a much lower RPM range... BIG task indeed.

It would be difficult to get to your goal with natural aspiration. Turbo, supercharge or nitrous would be your best and least expensive route to 400bhp.

If you go engine only you will have to turn more RPM than the stock computer will allow. 400hp at 5700rpm would take 368lb/tq. The Lexus 5.0 liter IS-F makes 371lb/tq at 5200rpm and roughly 350tq @ 5700rpm (torque drops with RPM from its peak) The IS-F is a bigger engine with nearly 12-1 compression and vvti on both intake and exhaust cams.

You would have to have a complete aftermarket engine management system to allow higher RPMs and allow tuning. You would need fairly radical changes to the engine.

My advice if you really want to do this is FIRST buy a SPARE 2uz-fe. Rebuild the engine with Lextreme rods and good forged pistons. Do your research and find owners that have supercharged or turbocharged their engines. Find out WHAT your options are for TUNING the engine. At the very least you will need to tune the air/fuel ratio. You will probably need bigger injectors and a better fuel pump. From their you can build a single turbo or buy the STS universal kit. This project will take time, research, money and patience. In the end you will have more torque and more fun for LESS money than OTHER OPTIONS. It will not be cheap... just cheaper than other options.

The spare motor allows you to build up and prepare while keeping your truck on the road. It will give you a back up if the worst happens and you have an engine break.

 

[mshawari1]

Whats it take to get 400bhp out of the 4.7 in my 4Runner.We have read the weakness in the stock rods and mains. Thanks for any replies

you could think about TRD SC kit.

Or

if you have the experience & time .... single turbo!!

 

[stevechumo]

My 4.7 Tundra is factory rated at 282 bhp and 325 btq.

 

[JBrady]

My 4.7 Tundra is factory rated at 282 bhp and 325 btq.

Must be a 2005. Looks like output varies from model to model year to year. Wiki had this for Tundra:
4.7 L 2UZ-FE V8
282 horsepower (2005)
271 horsepower (2006)

4Runner is rated differently? Per MSN cars:
2005 - 270 @ 5400 RPM - 320 @ 3400 RPM
2006 - 260 @ 5400 RPM - 306 @ 3400 RPM (same actual output as 2005 just using the revised rating system started in 2006)

Of course the IS-F and Coyote use the revised/lower numbers as well. To get an idea how the new numbers would compare to the old ratings add about 4% to the new numbers. The IS-F on the old scale actually makes 433hp. The LS460 rated 380hp would actually be 395hp... go LS!

 

[spf_lexus]

Hey John, do you know the differences between the 2 rating systems? I never understood why it was changed.

 

[stevechumo]

You're right. Mine is a 2005.

 

[JBrady]

Hey John, do you know the differences between the 2 rating systems? I never understood why it was changed.

SAE decided to more tightly regulate the testing for engines that wanted to be claimed as SAE certified tested for power.

From wiki:

Society of Automotive Engineers

SAE gross powerPrior to the 1972 model year, American automakers rated and advertised their engines in brake horsepower (bhp), frequently referred to as SAE gross horsepower, because it was measured in accord with the protocols defined in SAE standards J245 and J1995. As with other brake horsepower test protocols, SAE gross hp was measured using a stock test engine, generally running with few belt-driven accessories and sometimes fitted with long tube (test headers) in lieu of the OEM exhaust manifolds. The atmospheric correction standards for barometric pressure, humidity and temperature for testing were relatively idealistic.

SAE net powerIn the United States, the term bhp fell into disuse in 1971-72, as automakers began to quote power in terms of SAE net horsepower in accord with SAE standard J1349. Like SAE gross and other brake horsepower protocols, SAE Net hp is measured at the engine's crankshaft, and so does not account for transmission losses. However, the SAE net power testing protocol calls for standard production-type belt-driven accessories, air cleaner, emission controls, exhaust system, and other power-consuming accessories. This produces ratings in closer alignment with the power produced by the engine as it is actually configured and sold.

SAE certified powerIn 2005, the SAE introduced "SAE Certified Power" with SAE J2723.[15] This test is voluntary and is in itself not a separate engine test code but a certification of either J1349 or J1995 after which the manufacturer is allowed to advertise "Certified to SAE J1349" or "Certified to SAE J1995" depending on which test standard have been followed. To attain certification the test must follow the SAE standard in question, take place in a ISO9000/9002 certified facility and be witnessed by an SAE approved third party.

A few manufacturers such as Honda and Toyota switched to the new ratings immediately, with multi-directional results; the rated output of Cadillac's supercharged Northstar V8 jumped from 440 to 469 hp (330 to 350 kW) under the new tests, while the rating for Toyota's Camry 3.0 L 1MZ-FE V6 fell from 210 to 190 hp (160 to 140 kW). The ES330 and Camry SE V6 were previously rated at 225 hp but the ES330 dropped to 218 hp (163 kW) while the Camry declined to 210 hp (160 kW). The first engine certified under the new program was the 7.0 L LS7 used in the 2006 Chevrolet Corvette Z06. Certified power rose slightly from 500 to 505 hp (370 to 377 kW).

While Toyota and Honda are retesting their entire vehicle lineups, other automakers generally are retesting only those with updated powertrains. For example, the 2006 Ford Five Hundred is rated at 203 horsepower, the same as that of 2005 model. However, the 2006 rating does not reflect the new SAE testing procedure as Ford is not going to spend the extra expense of retesting its existing engines. Over time, most automakers are expected to comply with the new guidelines.

SAE tightened its horsepower rules after some engineers noticed parts of the old test could be subjected to different interpretations. Under the old testing procedures, there were small factors that required a judgment call: how much oil was in the crankcase, how the engine controls were calibrated and whether a vehicle was tested with premium fuel. In some cases, such can add up to a change in horsepower ratings. A road test editor at Edmunds.com, John Di Pietro, said decreases in horsepower ratings for some '06 models are not that dramatic. For vehicles like a midsize family sedan, it is likely that the reputation of the manufacturer will be more important.[16]

 

[stevechumo]

That's a very informative post, John.

 

[spf_lexus]

Thanks John, very informative stuff. Thats a reply even Wikipedia would be jealous of