jibbby

I have asked this question on the Lextreme forum and it could not be answered to my suprise..only guesses.....Maybe there is someone on this forum with facts and experience...

Question: Has anyone actually blown an !uz-fe engine from producing too much power HP?

I have searched all forums and came up blank, most blown 1uz-fe motors have come from tuning problems, over reving, or timing... Have yet to see or hear about a cracked piston or damaged rod which are supposedly the weakest internal engine parts of the sc400 1uz-fe.....

Member RDM - has made 378rwhp on the stock engine before his forgies were installed...It is safe to say I have come close to those numbers once or twice with a fully charged and heated 10lb nos bottle...No problems just impressive power...Tranny shifts were troubled abit.. Can anyone comment with facts on this subject, at what point are the pistons and rods really compomised on a well tuned 1UZ-FE motor?

The nos pro's and engine builders whom I know tell me these engines can take what ever the stock injectors can put out.... They are thinking 500rwhp with nos and I am in thinking the motor can handle it too....

I have ordered stock tranny buildup parts and now plan to up my nos shot and possibly ad some Kelford cams shortly and am not going with forged pistons and rods just yet...Would love to know the facts. before trying.....Anyone?

verylost

You will never get a flat out answer.

Every engine varies from the factory. Every engine is put under different stress conditions. Some engines are older than others. No two engines are alike and no two engines will fail at the same exact limit.

xirforever

you are right about your first comment, but not your reasoning. You wont get a flat out answer because there havent been enough blown from too much HP to make a general answer IMHO

jibbby

Verylost and Xir - you guys are both right I cannot find one blown engine that was well tuned....Unbelievable..... I also know that I won't get an exact number and every engine is different but just looking for a estimate or average...

Peewee over on Lextreme forum reported a stock IUZ-FE motor reached 400rwhp on a dyno but that motor was tuned to perfection, but no falure reported....... So 376rwhp just went up too 400rwhp.....This is what I am trying to find out.....Anyone else?

I am starting too believe people are putting in forgies more out of fear and precaution then out of pure necesity...

verylost

No, my reasoning is correct.

If you take 100 hundred aluminum rods and do a stress study, you will find variability of the stress limit at which these bars fail. Same with engines. There will always be variability.

xirforever

Obviously, but jibby wants a safe estimation/average. And variability between engines is NOT why we dont know. For example LS1's people know alot about and what they can generally take before they go ka-put, and they know this because there are a ton of them and a lot of people into those motors. The 1uz doesnt have this kind of attention and thats why we dont know. Your basically saying nobody could ever possibly know on anything because every motor is different. And thats a bit essentric. I could say my p/s system could just spontaneously combust because its "different" than yours.

Obviously condition of the motor should be taken into account, but like i said, obviously

AME_VIP

iTrader: (2)

good luck with your tranny build! I think that is the weakest link on the SC400. I don't think you'll find the limits of the SC with nitrous. I believe Todd from TMengineering had a 250 shot? Maybe 300 I can't remember now.

How about Emerald or Lextreme? Surely with standalone, dyno tuning and a turbo setup one could be making 400whp+ on the 1UZ?

jibbby

Still searching and I am still at 400rwhp without failure and this appears to be the most anyone has put out on a stock 1UZ-FE..motor before getting nervous and installing forgies... I am still hopeful for some increased number testimonies, and not just hear say... I have this same thread posted on other forums and looking for some more facts.. ..

400RWHP and climbing anyone else?

rdm20fan

Jibby, the stock fuel system won't make 500 or 400RWHP the injectors were maxed out at seventy some PSI of fuel on my setup when I made 370RW the reason i couldn't go higher was a lack of fuel.

And I agree with TurboTeg the trans is by far the week link. at 320RWHP the trans lasted 3 or 4 days, and I wasn't driving very hard either. My trans had 150K on it, so i thought that may have added to the failure, but a new trans lasted 2 ro 3 days longer.

Even after building it, we still had slight problems, but that was at 500RW.
The stock internals can handle over 500, but the fuel needs to be correct or the pistons will fail quickly. I don't think the stock pistons will handle lean conditions, or detonation for any time period.
But if you run the correct fuel, and enough of it, I think the limit of the stock motor is well over 500

I'm planing on putting 25PSI on the stock motor except for the forged 8.5:1 pistons.

millions

I believe hes making ~400 rwhp with NOS, which adds in fuel separately of the injectors... so long as the fuel pump can provide enough flow.

Though this all is great information, I too can't wait to start building my v8 as well. I got plans, but they'll be waiting till I finish off the MR2.

jibbby

Millions, not me at 400rwhp I would be lucky to make 330-350rwhp... I am searching to see who has put out the most hp with out forgies on this motor...I found 400rwhp on a well tuned 1uz-fe and no problems reported....

RDM - Thanks for the info.....

Now to this point these are the facts that I have now found from this forum and others......

***THE Stock 1uz-fe engine can handle 400rwhp with a proper fuel A/R mix...The stock injectors are pegged at around 370whp and going lean from stock injectors is the main cause of engine blows and not just RDM but others too that I have read up on.....Lastly the stock rods I have determined can handle 500rwhp+ and probably more....

Good info and we are getting somewhere fellas...Rdm has come up big....Thanks .Keep it coming...As you can see I am on a mission to find all the facts....Thanks for the replies...

AME_VIP

iTrader: (2)

wait wait wait Does this mean you put your car on the dyno and got 400 rwhp?

Wow RDM . I had no idea the tranny was that weak!! I put down 297whp with 150 shot untuned. Now I'm scared to make any more power! Granted I don't use the nitrous a lot these days.

rdm20fan

I read over n over from the supra guys that the auto would fail around 350RWHP. I'm sure the 3.0 make simular torque at 350hp as the 4.0L will make at a 320? probably more torque from the V8 (I'm guessing) The torque is whats killing the trans.

If I was making 300rwtq, I would start looking into something for the trans.

jibbby

Turboteg welcome to my world, I have been scared for about 6 months now......Feel signs of a troubled transmission for some time now....Order the parts or swap before it's to late....Lex wasted two trannies already at around that same hp power output...

Oh and TurboTeg no I did not put my car on the dyno and you know that, I thought we got beyond that....This is the info I have been gathering from this forum and all others....Trying to see what these stock motors can really handle...Trying to decifer what is fact from fiction...I found that another person had dyno'd their stock 1uz-fe motor at 400rwhp and not me....That is the most hp I found to date that the stock motor is dishing out without failure...It sounds like your getting close with your 150 shot....220rwhp + 150rwhp = 370rwhp.......Watch out for tranny failure that is all I can say to you.....

jibbby

Ok, new info has come in....We know that the 1UZ is a stonger motor then the 2UZ... However, someone on another forum has pushed the 2UZ.. stock motor to 420rwhp with good tuning and blew the motor while running nos.....From what he could tell the 2uz rods and crank failed at that mark...He was running nos and making 8:20's on the track.....THis is the 2uz motor and not the 1uz.....

We know the rods are stronger on the 1uz as compared to the 2uz, but not sure about the two cranks in comparison......

It is probably safe to say we are now up to 420rwhp on a stock 1uz-fe engine if well tuned...