Blowing up the 1uz-fe

[jibbby]

Hey guys, here is the deal...I have just ordered some tranny building parts for my SC4 and have the plan in place to beef up the drivetrain and tranny to handle increased HP loads... My plans are to increase my nos shot....Now I need to deal with the stock internals of the engine....

Engine - The 1uz-fe engines are good from what I hear to about 375rwhp then the pistons and rods are comprimised...Is there anyone that knows for sure what exact Hp load the stock engine components can handle before the KA BOOM happens?...Has anyone actually blown a stock Iuz-fe from pushing too much well tuned power and not from bad timing and A/F mix???

I am not ready for forgies just yet, and want to know exactly what I can expect to push out of these stock 1UZ-FE's...Anyone? I have heard different stories over the past year... I have probably pushed 350whp if lucky once or twice with my juiced and heated nos bottle on my current 1UZ..motor and experienced no problems what so ever just heathly crisp engine power...Can a stock motor handle lets say a consistant 400-425rwhp without cracking a piston or damaging a rod? My plans are to increase my nos shot to a 150-200hp dry shot rather then the 100-150hp shot I am currently running... What do you guys think?

I am not that concerned about blowing the motor, as I can replace it with a stronger one or rebuild as needed if the block is good...but also don't want to create massive damage or lock up and crash...Or worse have an engine fire....Can anyone tell me what is most likely to happen when the motor blows from too much power? I have never blown a motor...

 

[rdm20fan]

Jibby, I made 510 at the rear wheels on an early 1UZ with forged pistons.
I just took the motor apart due to an injector failing.
now the failed injector destroyed the piston, but the motor other then that looks great.
With stock pistons I made 378 at the rear wheels, and I believe if the tunning had been better it could have gone past that with stock pistons and internals.

My local speed shop claims they have a friend at TRD who has pushed the early 1UZ to 1000HP at the crank.
I have no idea if it will live through 1000HP, and if it does, for how long. But I have trust in the shop, and see no reason why they would be dishonest. The owner, and head tunner are both putting together Supras with early 1UZ's running alchol on a stock 1UZ.

 

[jibbby]

RDM - Thank you for the reply..very informative....Now, I have heard this and that about the early 1uz-fe engines and what they are capable of handling but nobody can tell me for sure what exact HP output do the pistons or rods fail...It is my understanding that those two internal engine parts are the weak points of the 1uz-fe motors.

378whp is probably close to the output my motor has seen once or twice while running on a chreged and heated nos shot.... However, I find it hard to believe that you could reach 1000hp on stock internals and if that were the case people like you, Lex, and others would not be installing forgies....With that being said I am going to test this motor and see what it can handle...I do think it can handle well over 400rwhp without failure and so do some of the experts I know that are familiar with these motors... It's just funny after all my searches I cannot not find one factual story of the engine blowing due to excessive horsepower....Lot's of opinions, and when the motor has blown in some cases it was due to other causes, foul tuning, timing, over reving, etc...never from straight power output...

This is why I posted... One other thing I have been told that NOS detonation in the piston chambers is more excessive and powerful then standard fuel, the nos experts and pro engine builders are betting these engines will handle what ever the stock injectors can dish out or maybe even more with an AFI application....Until I hear an actual story of an 1uz-fe blowing up I am going to up the nos output after the tranny build and see what happens unless otherwise told not too from factual testimonies....

RDM thanks again for the numbers and reply post..I also admire your SC400 as you are most likely already aware of......I have ordered the same tranny parts that you did for the Tranny buildup, and am using a local tranny shop to do the work..... Wondering do you have a shift kit on your setup...There is one available for the SC400...

Does anyone else have any opinions on this subject Peewee, Zuffen, LEX, Pro, Toysrme, Sc400TT,Cribby, even Mycarpossessme, this topic with factual proof can help many others besides me.....

 

[Peewee]

Its all in the tuning Jibbby.

A poorly tuned motor may die at less than 200rwhp.

But there are reports of people around/over the 450rwhp mark on untouched internals. These guys have their motors tuned very well.

 

[jibbby]

Thanks Peewee-

That is basically what I am being told..If your well tuned you can get alot out of these stocks motors....I am thinking of trying for up to 500rwhp with good tuning after the tranny parts come in and the drivetrain is builtup to support the hp's...

 

[skid]

....I am thinking of trying for up to......

Stop thinking - just do.

 

[Lextreme II]

jibbby.... do it and blow your engine... so u have an excuse to get forgies... I think a 5.3 high compression motor is what u need. I am thinking about selling my 4.7 4 bolt main forged shortblock and stroke it to 5.3 4 bolt main shortblock...... http://lextreme.com/forums/showthread.php?t=5579

 

[jibbby]

Skid, my boy wihen I stop thinking that is when I end up in the hospital.... I guess I am becoming less reckless in my older age....

Don't really want to blow my engine if necessary, however with the 400-450rwhp and the progressive nos shot that "I WILL DO OR LET'S SAY WANT TO DO"... I am just a little worried about the engine blowing up and me too with it:newangel: , concerned about maybe an engine fire, or lock up and crash... Don't care about the engine and block itself, besides I have been just itching for a larger power plant anyway.

I am posting this to see who blew up first and I am trying to avoid being the ginnea pig on this one.......

Onto my next irratating question? What happens when the engine blows while racing? Never had one blow on me, do the heads fly off, does the pistons usually freeze up in the block, do pistons and rods shoot thru the hood, tires fly off? (just kidding with the tires) I want to know what to expect when blowing the engine under nos at 80mph...

If you fine motor heads can answer that last question for me then I will just do as skid says, and stop thinking and do and stop posting so much.. I have this same thread running on the club...got a few quality responses from RDM80, and verylost that is it...This really is a mystery on what these stock motor can handle with good tuning....

Lex why are you selling a Toyota 4.7L with forgies in it for, are you nuts? That sounds like a wonderful engine...What cams are in it and how much do you want for it?

 

[Zuffen]

Jibby,

Back when I raced (in the '70's) I dropped a rod in my racecar. For the Aussies it was a Series Production Torana GTR with the 171 engine.

Other than the oil light comming and it running a little rough the oil under the rear tyres was the biggest problem.

The rod dropped straight through the bottom of the sump. No head damage, no cylinder damage and a chunk about the size of your little fingernail out of the skirt of the block.

One new rod, piston, crank sump and gaskets, rings etc and it all went back together.

Whne pulling it down we found 1 bigend nut sitting in the bottom of the sump. The nut came loose and that was the cause of the blow up.

 

[rdm20fan]

Hey Jibby, When my piston failed at 370, it was because of a lean condition. And the 370RWHP was maxing out the fuel system. Only 1 piston melted. the other 7 looked perfect.

I've done a little research on rods, and most rod manufactures will rate the HP per rod. as in 100HP per rod. 400HP for a 4 cyl, and 800hp with the same rod on an 8 cyl.
The 1UZ rods are simular to the Supra 7M-GTE rods.
I have seen the stock 7M-GTE rods make 550RWHP & 30PSI.
That makes me think the stock rods will hold over 700RWHP on the 1UZ (Early version)
I think it's safe to rate the stock 1UZ rod at just over 100hp per rod.
I think just over 800hp is doable, but I don't think they can handle that on a daily basis.
Just my thoughts.

 

[rdm20fan]

And about the trans. One of the clutch packs needed to be "Mantised" Chris did some custom grinding of different clutches to get them to fit.

The negitive is the set that he had to customize was the clutch pack which failed. The trans supplier claimed they could not get the correct Raybestos Blue disc for the pack.

When I called Raybestos they gave me a part # for the Pack. (I forget which pack it was) The discs are the same as a different set in the trans. the center is the same, and will work, but the overall diameter is larger. We had to have them cut down to fit.

Chris and I did shim all the acuator springs to have them shifter harder, and upped the line pressure.

The stock trans fails pretty quick. it will hold 300Ftlbs of torque for very few runs. the SC is a fat heavy pig, and thats alot of work for the trans to do.

 

[cowboy bebop]

Great posts, RDM. Here's the major issue I can see with the early 1uz rods. The shank of the bolt is .0050 less than 1/4 inch. That's not stout enough to handle big HP for long. The good news is that the threaded portion of is very nearly 3/8 inch, so a replacement ARP 2000 or L19 bolt will increase the overall performance of the early 1uz rod.

Eric

 

[jibbby]

We are getting somewhere fellas!!!! Great posts from all of you guys, thank you, as you can see I am on a mission to find facts!!!!!!.....Now to this point we have determined that the stock !uz-fe can handle 400rwhp safely with good tuning and defenitely not a lean fuel mix.. The rods have weak points but should be able to handle well over 400rwhp safely and most llikely with some left over......Stock injectors are pegged at approxiametely 370 rwhp before you go lean and blow....Any more info anyone might want to ad???????

Getting some good results here, keep the info coming fellas this is big...Other forums are coming up empty and have no clue.... this one is producing all the results..GO LEXTREME!!!!.... :arms:

Now on a personal note - people running larger nos shots like me, the fuel mix must run slightly rich anyway rather then lean. So I believe larger injectors are a must to keep the fuel mix in check when going big... From my findings and readings it is the lean fuel mix from maxing out the stock injectors which has blown these engines everytime...RDM you are not the only one who has done that........Redlining with nos is going to be the test on the stock pistons and rods ....retarding the timing at higher rpm's is going to be important in maintaining the engine while riding the juice..

RDM - I hooked up with a performance tranny shop here in LA, currently working out all the ordered parts, and the buildup plan will be very simular to yours, if I have question I will PM you if you don't mind.. The tranny builder is very confident in his plans....We are shooting for a 500-600rwhp capacity and have been working on a shift kit plan just today...Will no more shortly....

 

[skid]

Jibbbbbbbbbbbbbbbbbbbbers old boy,

Nitrous is as safe as houses if done properly.

Stop worrying about everything as you appear to be going around in circles. As I said... just do!

In doing I would suggest leaving the standard injectors alone as they handle your engines current air/fuel ration I guess satisfactorly.

Therefore you need 8 dual Nitrous/Fuel injectors as these will be matched to provide the right amount of Nitrous and petroluem. Therefore you car will drive as is now but when you activate the system the current system continues to run in the right ratio, and the additional Nitrous system will do it's bit in the right ratio again.

( I'm calling Yank 'Gas' petrol, not gas, as often Yanks get confused when talking about a Nitrous system with a gas bottle feeding nitrous gas and needing additional 'Gas' to work. Funnily enough Nitrous is associated as a gas in a bottle but it actually operates best when delivered through the system as a liquid right up to the injectors where it the enters the inlet port/plenum mixing with petrol during which it heats and turns to a high pressured gas/atomised petrol mix. )

In additon you will need a programmable unit. I used the Jacobs Nitrous Mastermind which on activation automatically retards the ignition (adjustable), has a Nitrous rev limiter and then an engine rev limiter 50 revs after. This is adjustable up to about 12000 rpm I think and prevents the engine cutting limiting and cutting ignition but sending unburnt Nitrous/Fuel mix into your exhaust system which would probably blow the exhausts off!

It also has a progressive system so it could bring the Nitrous in at say 3000 rpm and at 40 % building up to 100% flow at 5500 rpm then have a rev linit at 6500???

You would also need an extra fuel line and seperate pump to provide the Nitrous system with petrol, and you can add safety devices such as pressure cut off switches and I even put a 'knock' device which kills power to my Nitrous electric petrol pump in the event of an accident.

In theory a proper system could have a massive extra hit if done properly.

So for example if your car has (at the crank) 250bhp, you could add a 400bhp ysytem.

Properly set up your 250bhp would lose say 50bhp when the system activated and retarded the ignition. Then the Nitrous system properly balanced could flow the 400 on top. With a progressive system it could come on in gradually across the system.

Just do...

Mark

p.s. I set up a 175bhp system on my AC CObra with the help of Mark Wiffen who runs an old nail of an air cooled 10 year old Suzuki which is (or maybe was now) the fastest road legal bike in the UK. He is a fluid dynamics graduate engineer and I learnt a lot from him. If Lex is interseted I could detail it all for a sticky to save people asking the same q's every 3 months.

Mark
p.p.s sorry for appalling grammer was in a rush to type this while at work!

 

[rdm20fan]

Great posts, RDM. Here's the major issue I can see with the early 1uz rods. The shank of the bolt is .0050 less than 1/4 inch. That's not stout enough to handle big HP for long. The good news is that the threaded portion of is very nearly 3/8 inch, so a replacement ARP 2000 or L19 bolt will increase the overall performance of the early 1uz rod.
Eric

Thanks Eric.
LS1 Rod bolt!!! Bought ARP LS1 rod bolts from Summit for $80-90 bucks, and they work. They are going in for the new rebuild.

RDM - I hooked up with a performance tranny shop here in LA, currently working out all the ordered parts, and the buildup plan will be very simular to yours, if I have question I will PM you if you don't mind.. The tranny builder is very confident in his plans....We are shooting for a 500-600rwhp capacity and have been working on a shift kit plan just today...Will no more shortly....

Feel free to PM Me. I have no secrets, and will be happy to share my experiences.

I'm planning on over 600RW, and the first thing I'm doing is smashing the Auto with a hammer.
You probably can get the A3430E? (Did I screw up that code?) to handle the torque, but I'm feed up with it's problems.
Chris and I are attempting an 87 Corolla with a TT 1UZ, and chris wants to use the auto Lexus trans.
The shift kit is simple. any trans shop can figure it out. you can replace the springs with stiffer ones, or shim the stock springs.

Jibbbbbbbbbbbbbbbbbbbbers old boy,
Therefore you need 8 dual Nitrous/Fuel injectors as these will be matched to provide the right amount of Nitrous and petroluem.

I Agree completly!! If I were running NO2 i would use this type of system that adds fuel also, and not rely on the stock injectors.
If you r planning on anywhere near 370RW I would do something else for fuel. At 370 I had the max pressure I could run, and still get the car to idle.

 

[jibbby]

Skid ole chap.... Thanks for the nos breakdown, already aware of your fine nos facts...Remember. I have become a bit of a nos junky over the past year, sounds like you have it mastered on your ride....must be nice and fast.:439:

Just for your info there is an SC putting out 700whp off of nos alone, and of course had a built engine and tranny going on... Seen it a year ago and was amazed, multiple nos tanks the works..Built by TM engineering...It cost the owner a small fortune to set it all up...$7000 if I remember correctly.. That is when I knew nitros could get the job done.. with a 500hp nos shot talk about nos bottle refill costs, ouch!!!....He should have done AFI for that money......Anyway, I am not thinking about that kind of output with nos maybe just an addition 50-100hp shot in addition to what I have running now. I plan on keeping my dry nos system intact and stock engine internals and save the cash for some other monster project in the future... I am not switching to a wet system and forgies which I probably should do.....See where I am getting at????..

My efforts on this thread is to see what is possible with the 1uz-fe stock internals... I may be going around in circles but I am gathering bits and pieces of info.which maybe helpful ot others or give an idea as to what parts hold up to what Hp...What can be achieved and what cannot...I am getting a little dizzy from going round and round and am just about to fall over :1244: so no worries my friend as I am almost done..Just want to decifer what is fact from fiction.... So you say, like the Nike commercial says, "Just do it"....

My goal is to compile as many facts first and post the results for all to see on one thread and also for shmucks like me whom want to push the limits and don't want to bore out the block and install forgies for thousands of dollars.. It's kind of a pain searching each engine thread on every forum to find answers that aren't their or are all different... Wouldn't you agree?

 

[rydning]

The most important thing to do when the engine blows up is to get the tranny in N or push the clutch pedal....Me and my buddys have blown some engines and most of them is because of lean mixure (broken piston) mostly redused power.And some with to mutch boost,the engine detonate under hige load hige speed (cant hear the ding ding...)and a rod or 2 is going true the block,more and more noise to the engine doesent go more or get stuck....

Is the quis how mutch Nos you can put in to a stock(never modifyed) 1uzfe??
Or is it how mutch it is possible to get with turbo and modifyed stock parts?

Just make some simulated training how to get it in neutral and add more N2O/fuel then you will figur out....

 

[rytherwr]

Comes apart

Jibby,

To answer your question about blowing a motor...I haven't blown a 1uz but I have blown a 2uz running 9 lbs of boost (supercharger) and 150 hp shot of nitrous. I had about 150 runs on the completely stock motor when it blew. The bottom end (with the exception of the crank) came out the sides and bottom of the block. Broke 5 rods and 4 pistons, destroyed the block etc. Pics can be seen at www.lextreme.com/tundra.html . You can also see how I am rebuilding in the same place. Hope this helps. Rods are a lot smaller cross section than 1uz.

Wayne

 

[jibbby]

rytherwr - May I ask you if you think your 2UZ ran lean at the time of your engine destruction? Also I believe the 1UZ is a stronger motor from what I have read but don't know for sure...Don't know if you can compare the two motors exactly, atleast I know I can't but maybe someone else on this thread can... Lastly what was your estimated rear wheel Hp when this destruction happen? Were you running the stock injectors at the time? The reason I ask is that around 370rwhp the stock fuel injectors are pegged, so going beyond that point means you probably will run lean and go booom....Especially when running nitros.....Better luck with you next motor..and thanks for the input....

 

[rytherwr]

Jibby,

You are correct on a number of points...1uz is much stronger than 2uz...mainly in the rod area....heck, the tundra motor is redlined at 5300 rpm! Also correct in not really being able to compare the two motors apple-to-apple. Wasn't running lean as evidenced by pulling the plugs quite often after a full pass, in fact it was a little rich as I am running a Supra TT fuel pump and the stock ECU adjusted after a while, but you could still smell a little rich. I was running 8.20's in the eighth mile, can't know for sure but calculators on the web show rwp at approximately 420. Having said that, I was using stock injectors, however, there are two 60 lb pico style injectors in the rear of the TRD SC that are activated under boost by the TRD piggyback computer. I was running a wet shot of nitrous injected just before the TB and ran it a couple of numbers rich as well. Just for giggles, I also run a water/alcohol injection system that is variable by boost pressure, so all the elements are there. The bottom line is the stock 2 uz is not up to the task...especially the cylinder pressures I was generating...looks like the rods went first...couldn't really see a sign of detonation when I took it apart. Anyway, hope this helps and thanks for the well wishes. Just have some machine work on the crank and rods to get completed before we trial fit the pieces. Will post as I get it up and running.

Wayne