Realistic performance goals for light build-up of 1UZFE

[Kreb]

Realistic performance goals for light build-up of 1UZFE?

1UFZE (SC400 donor onto kit car):

The build I'm considering will feature headers at a minimum. A chip and cams seem like the appropriate first stage of build. Emissions are not an issue. I'd like to get over 300 HP while maximizing my usable RPM range. Is 8000 RPM realistic on stock internals?

 

[400ZED]

That sounds right 300 at the wheels with cams exhaust and aftermarket managment it probabley won't breath to 8000 mine makes peak at 225@5700 and does very little after that it drops off quick. with cams it will rev to 8000 but i don't think there will be any point as i doubt peak power will be much over 6700. i think 300rwhp is at the top of what you could expect. if you want a little more and emmisions don't coun't you should seriousley look at individual throttles. all depends on what cams you run. don't take my word as gospel.
keep me informed as to where you get the cams from and how it goes.

 

[Pro]

8000rpm is very realistic on stock internals, but you have to be able to make it breathe. cams and custom headers will be a minimum, but the std inlet manifolding should be fine. of course after the cams and headers you'll need a comp change and/or re-tune.

or fit a turbo and be done with it.

 

[Kreb]

There are a few reasons that I want to stay away from forced induction. The first is weight. In a sub 1500 pound car, the turbo, intercooler and related plumbing will throw more weight on the nose where I don't want it.

Secondly, I need to be wary of my own and the car's limitations. The astronomical HP figures possible with turbocharging could easily start overwhelming the brakes/chasis/drivetrain. It could also end my life, and as I'm no longer a kid, the risks associated with 3:1 power to weight ratios don't sound too enticing.

I've just started looking at junkyards for 1UFZEs and it's amazing how cheap and available they are. It's easier to get a nice one than it is to get a nice GM Iron Block 3.4 - and they're more likely to be taken care of than your average S-10 or Camaro.

 

[Miles B]

300 at the wheels? I'd plan on head work.

 

[400ZED]

Kerb
sounds like you understand more is not always better. in 1500 pound car a 1uz will give you enough stick and more than 300rwhp and you won't get it to the ground ever not that 300 will be exactley tyre friendley.
IMO a NA would be your best option with some head work and cams. Throttles (because they would beso cool) and exhaust and an aftermarket computer you will have a nice little rocket.

 

[JBrady]

Early 1UZFE engines are rated 250hp engine but with stock exhaust and intake components IMHO make about 235 flywheel hp. Stock cars with soft/smooth automatic and heavily dampened driveline and suspension (lots of weight and power absorbtion) leaves a good example making 180rwhp.

Install that same engine with a lighter drivetrain (manual tranny) more firmly mounted components, and you should get about 15% drivetrain loss. 235 - 15% = 200rwhp. A really good exhaust could gain 40rwhp. Aftermarket pistons (properly designed and prepared) to both raise compression and improve efficiency, coupled with 220 degree (at .050" lift) cams, gentle porting, a high flow AFM, and larger injectors... should yield 280-300rwhp (330 - 350 flywheel).

Now, add up the above costs (not counting exhaust) and compare it to finding a 1998 or newer 1UZFE or 3UZFFE...
300+ flywheel hp stock (255rwhp). A really good exhaust should add an easy 30 rwhp (285rwhp). Torque curve is MUCH better. Intake MUCH better. VVTi cams MUCH better. Very smooth. Newer everything. If you find a 3UZFE you will have a 4.3 liter engine. These numbers are using the stock 6350rpm redline. Add an aftermarket ECU and raise the redline to 7000rpm on the above engines and you should have at least 300rwhp. There are probably cams available from Japan. Cams and good headwork could make this package approach 400 flywheel hp. At that point you may need a bigger throttle body. A full out effort on this base package, turning 8000rpm could make 450 flywheel hp (335 rwkw for you aussies)

 

[Nick M]

Install that same engine with a lighter drivetrain (manual tranny) more firmly mounted components, and you should get about 15% drivetrain loss. 235 - 15% = 200rwhp. A really good exhaust could gain 40rwhp. Aftermarket pistons (properly designed and prepared) to both raise compression and improve efficiency, coupled with 220 degree (at .050" lift) cams, gentle porting, a high flow AFM, and larger injectors... should yield 280-300rwhp (330 - 350 flywheel).

Since when does an exhaust add 40 rwhp? Maybe on a blown Mustang Cobra. If you had a perfectly tuned exhaust and dumped those oversized mufflers, you might hit 20rwhp.

Where are you going to get a high flow AFM? Aftermarket pistons with more compression is a good idea. So is your more aggressive cam.

 

[Kreb]

Thanks a lot you guys. It sounds like JBrady may have a point regarding the later VVT versions versus the earlier ones. Factoring in budget and my relative lack of mechanical expertise, the later engine may be the ticket - I could meet my goals with free-flowing exhaust and a chip, and not have to open up the motor. If (when) I get greedy down the road, there's a good deal more performance available.

I'd probably get an adaptor to go to my existing GM 5-speed tranny, so I'd need a special chip anyway. Here's a few more questions for you all:

-Assuming a custom chip, who'd be the best vendor? What sort of cost are we looking at? And can the chip be tuned by Northern Californians?

-Are the later engines significantly heavier? I've heard to expect around 400 lbs. for the bare motor on a earlier 1UZFE, but some of the later engines are beefier, right? Any other considerations I should know?

 

[JBrady]

Since when does an exhaust add 40 rwhp? Maybe on a blown Mustang Cobra. If you had a perfectly tuned exhaust and dumped those oversized mufflers, you might hit 20rwhp.

Where are you going to get a high flow AFM? Aftermarket pistons with more compression is a good idea. So is your more aggressive cam.

Nick... are you asking me or telling me? Have you followed my threads on exhaust?

Again, here is my quote "A really good exhaust could gain 40rwhp"... please note the parts about "really good" and "could"...

The early stock exhaust manifolds are terrible and the later parts are marginally better. Absolutely not designed for flow and DEFINITELY not designed to scavenge. The remainder of the stock exhaust consists of dual 1.9" pipes feeding a single 2.36" pipe. How much power do you think is in this exhaust just by letting it breathe? 20rwhp is very reasonable... don't you think? Now, apply some SERIOUS scavenging exhaust science... you know... the "really good" stuff... and another 20rwhp is obtainable. I am not suggesting any old system will gain 40rwhp but it is not by ANY means impossible. Notice also that the potential for 40rwhp was quoted for the EARLY engine (see above post) and that I used a very reasonable/probable 30rwhp for the later engines (40 may be doable on later engines especially 4.3 liter versions). BTW, one of the SC400 guys at Club Lexus who is also a moderator (VSsc400) dyno'd at 210rwhp after a cat back exhaust system with an X pipe. The stock car makes maybe 180rwhp. Right there is 30rwhp reported for just cat back using the VERY BAD stock manifolds. (I have posted pics of the manifolds and more in the exhaust forum here at Lextreme)

The oversized AFM is currently available from SRT for the 1998+ engines. It utilizes a 3.5" INSIDE DIAMETER aluminum pipe that accepts the OEM air meter element and runs a piggy back ECU to compensate for the change in flow readings.

My piston suggestion is for the early 1UZFE as the 1998+ version is higher compression. My cam suggestion is to look to the Japanese tuner market as they probably have available cams with more lift and duration.

Kreb,

I do not have first hand ECU advice for these engines but it looks like AEM has a direct replacement ECU that fits the factory wiring harness. Some have said the Unichip may work but others say the OBDII computer keeps trying to re-tune to factory parameters... sorry I cannot add... maybe others here will chime in.

BTW, is your GM 5 speed an automatic or manual tranny?

Basic config and dimensions (alloy block and heads, iron sleeves) remains unchanged so weight should be fairly close between engines.

 

[uzz32pete]

Stage one: Stock
Stage two (+18 rwhp): Intake (BFI) and exhaust, stock headers, +18 rwhp
Stage three (+25 rwhp): Headers +13 rwhp
Stage four Unichip (+43rwhp): +18 rwhp (torque gains everywhere)

Note: My Unichip was custom tuned on the road with a technician wearing headphones listening to engine microphones. I don't expect anyone behind a counter to be able to pick something off the shelf to plug in and get an optimal tune. Improvements yes, but optimal tune and max power no.

The above are my general observations from 3 years of dyno testing of Australian V8 Soarers at various member dyno days.
A definite pattern is taking shape. Intake and exhaust get you so far - then a jump with headers is very common. All the V8's run very rich with stock ECU, especially so with any intake and exhaust mods. These are all 1UZ-FE engines. I've never known what timing is run on the V8. A MiNes ECU which "turns down" the knock sensor inputs gives noticeable improvements. The technician said they were able to dial an extra 6 degrees of timing and lift air fuel ratios from 10.8 to 12.8 without a hint of detonation on road.

I didn't list the total rwhp because it varies country to country, dyno to dyno etc.
I don't know much about the inner workings of the ECU. The Unichip affects the timing during closed loop running, fuel and timing during open loop. The biggest thing for me was the blasting of the line with the Unichip rather than the typical 1UZ-FE plod.

 

[uzz32pete]

Timing graph for the 1UZ-FE - downloaded from the Toyota ECU in my car.

 

[Miles B]

Uh... maybe my math is off Pete, but the headers only added 7 to me.

 

[Miles B]

JBrady,
335rwkw is a big stretch of the imagination. Vipers with $10k+ US of headwork, extractors, exhaust, ECU tune, cam and rockers only add about 150rwhp over stock. As our engine is half the size, I would bet on half the gain. 75rwhp. 50rwkw. A stock SC430 here is hitting about 155 rwkw. I really do not see any way you are going to more than double that with an NA tune without pistons. I am hoping to hit that number with 1 bar of boost!

If anyone can show me an NA 1UZ, without some seriously hi comp pistons, putting over 250rwhp, I'd be very very surprised. Maybe with some really really good head work.

 

[JBrady]

JBrady,
335rwkw is a big stretch of the imagination. Vipers with $10k+ US of headwork, extractors, exhaust, ECU tune, cam and rockers only add about 150rwhp over stock. As our engine is half the size, I would bet on half the gain. 75rwhp. 50rwkw. A stock SC430 here is hitting about 155 rwkw. I really do not see any way you are going to more than double that with an NA tune without pistons. I am hoping to hit that number with 1 bar of boost!

If anyone can show me an NA 1UZ, without some seriously hi comp pistons, putting over 250rwhp, I'd be very very surprised. Maybe with some really really good head work.

Miles, the problem with your logic above is it is based on basic observation of common mods on older (first generation) 1UZFE engines.

Consider...

BONE STOCK 1998 and newer GS400/430s dyno around 235rwhp with the soft tranny and luxury suspension and drivetrain isolation. With the SRT intake upgrade 250+rwhp is common. Pull this engine, install with a performance oriented drivetrain that looses 15% rather than the stock 22% and you are at 255rwhp BONE STOCK ENGINE.

With the SRT you are looking at 270rwhp. Surprised?

We haven't even started talking about what constitutes the RIGHT intake manifolding or exhaust headers or exhaust system or cams or headwork or increase in RPM operating range.

We are NOT talking about a Vipers 2 valve engine technology. We are talking about a very sophisticated, over square, 10.5-to-1 compression DOHC engine displacing 4 to 4.3 liters.

For a very reasonable comparision to the upper capabilities of this design... a comparision to Honda engines would be much better than a Viper. Lets look at the Honda S2000 engine. Essentially half of a 1UZFE. Stock, through catalytic converters, emissions compliant... this engine makes 240 flywheel hp. Double that and you get 480hp. Please do not tell me this is not possible.

The title of this thread is Realistic buildup. Take the 270rwhp above and add a realistic 30rwhp with a well sorted exhaust and you get the target 300rwhp or 224rwkw.

 

[Kreb]

Well that sounds more like it to me. I was thinking along very similar lines. Looking at 2-valve 1960s technology on one hand and DOHC VVT on the other, it seems that if the Lexus is the technilogical marvel it's supposed to be, you shouldn't have to cover too much ground to get some serious specific outputs.

btw, Im using a 5-speed manual tranny. The Stalker is very drag limited in terms of top speed, so there's no need for a 6th gear.

Now if my industrial designer friend comes through with that cool fibreglass body he keep threatening to design for me, we might have to start thinking about some more gearing.

 

[turboandrew]

IMO, a lot of these improvements still seem quite optimistic. Going with a later 1UZ does seem like a good choice. I was able to pick up a complete 1999 gs400 motor for $1600 USD. Starting with 240 rwhp instead of ~190 seems worth the extra money. After that I would go with programmable EFI (make sure you can control the vvti or go with the HKS box) leaned out to 12.5 : 1, probably good for another 5-10%, then headers/exhaust/intake, another 10%, then IMO, go for gold, turn it into a 4.7 liter or bigger and gain 15+% more.

 

[JBrady]

Here are some links to some stock and mild mods dynos on GS400s and 430s.

http://www.clublexus.com/forums/showthread.php?s=&threadid=72625

http://www.clublexus.com/forums/showthread.php?s=&threadid=111405&highlight=dyno

http://www.clublexus.com/forums/showthread.php?s=&threadid=109188&highlight=dyno

http://www.clublexus.com/forums/showthread.php?s=&threadid=102085&highlight=dyno

 

[Miles B]

OK notice where you have dropped 111 rwkw from your number? OK..

Secondly, there was a Soarer converted to 5 speed manual here and dynoed, and it LOST a couple of horses. What is so "power taxing" about the A341? Yes it is soft, but that is just the shift logic involved. The planetary gear set in it is about the same inertial load as a pair of shafts of gears in a manual box, and when the converter locks up, that's locked up like a manual's clutch.

The Viper must be doing something right - yes it is a 2 valve engine, but stock it dynos about 415rwhp. Halve that and you get 207rwhp. Which is more than my space age 1st gen V8 Soarer ever did AND the Viper does it with a lower compression ratio. Tell me how they pull that off.

The US Honda website says the S2000 is actually a 2.2 litre engine with 11.1:1 compression ratio and an 8000rpm redline, with its power peak at 7800rpm. It also shows the S2000 as having an UNDER square engine. Previous years I believe were almost square or very slightly over, and actually peaked at 8300rpm with a 9000 redline.

The 8L Viper is over square, has a fuel cut redline of 6200rpm. The redline on my car is 6250. Many have raised the redline on the Viper by 500 or 750.

The title of this thread is actually "light build-up of 1UZFE". That does not involve dropping in a 4.3. Yes, by changing engines you might get near 300rwhp.

I had a quick read of the threads you posted. We have:
262 with exhaust, intake, ECU
255 with same
249 K&N intake
249 K&N filter
230 stock / with exhaust

From your post, I was expecting to see "270 with no exhaust". What I see is a car with 262 with everything except (maybe) extractors. Which may add another 15 or 20 if they are REALLY good. I have seen a lot of headers and extractors put on cars. The best results I have seen was a set that cost in excess of 2500 US dollars, put on a Viper, and yielded mid 40s hp with exhaust. These were tuned length, lots of work done, real science. And they yielded just over 10%.

I hear a lot of people saying "get a really well designed exhaust and you'll pick up 50hp", but I don't see anyone doing it. Please prove me wrong. The fact is most people pick up 15hp with the first one they put on. For some that is the exhaust, for others it is the headers. Then people say "sweet, they add 15 each". Then 15 becomes 20, and 20 becomes "25 if you use a lot of science". The results are usually what Peter Scott shows. 15 for the first, and half that for the second.

 

[Miles B]

Stock dyno numbers:
Old Viper 8.0: 52hp/litre
My 1UZ: 48hp/litre
New Viper 8.3: 52hp/litre
3UZ: 54hp/litre

Not bad for an engine with 1 cam, 2 valves per cylinder, a lower redline and lower compression ratio.