1jz engine limits ???????

[al167]

hey everyone just thought you guys would love to know when a 1jz has exceeded its stock bottom end strength.
i was cruising down the hwy the other day at 110kph and out of know where no2 rod failed and went through the block leaving a tennis ball sized hole in its path.
when i pulled the engine down all six rods where bent like bananas .......

ths is the vvti version out of a jzx100 chaser

NOW
this 1jz has......
-only done 10000 kms and was mainly cruised though giving the odd squirt every now and then (or when needed )
- been in the car for 2 years
- ran most of its life at 22psi (365 rwhp) 11.8 ET @ 110mph
- ran aprox 10 passe at 32psi(466rwhp)11.14 ET @121mph
- gt 3540
- c4 trany withh 5000 stall
- 9 inch diff

i think i have found the limits of the stock rods !!!!!!!


i have some cool photos if anyone will show me how to attach them.

[tron]

yep. i found my 1jz's limits aswell, 409rwhp at 22psi for a long time + whatever it was used for in japan .

what u gonna do now?

[1JZ.747]

neither of you have found the limits of the engine, you have found the limits of your tuners ability.

i have run over 30 psi for a year. i have run 35 psi for while aswell. i havent had an issue.

you are getting detonation that has killed the rod. you are either trying to much boost on factory rods, or tuner has reached his level.

anything over 20 psi in these engine should have race fuel. the rods can handle the cyulinder pressure from the boost, they just cant handle to detonation.

example, im 85 kg, i can stand on a coke can and it will not crush or warp. some one gently flicks the side of the coke can and its will crush.

ie, bring in the detonation, rod gets a shock and hello broken rod.

hope that makes sense

Shane

as for power, my car weighs 3440 pound with me in it 137 mph trap speed, work out the horsepower, its well above the dyno reading of 498 i have.

oh, and the engine has done 194000k's and its for sale if you need another bottom end.

[1JZ.747]

oh and i think you need a smaller stall, your et are awesome for the MPH which indicates the convertor is too big, 11.8 you should be running 118 mph and 11.1 should be around 124 125 mph. there is a ten sec pass there waiting to be had with a tighter and lower stall speed convertor. 35/40 should should only need a 3600 or so

have fun

shane

penny has just dropped, you own the black hiace and you rang me the other day..

[JZA70 R]

the man has spoken.

still, interesting experience from all.

[whatthe?]

Worth remembering also that vvti 1Js have lighter rods than the non vvti, possibly a limitation there too?

[1jzracing]

i have to agree, but it sounds like an unusual failure!

i have run 477rwhp for LOOONG periods in my circuit car, it does the equivilent of 800 drag racing passes and well over 2000 full power up-shifts per season!!!..... i did 2.5 seasons on one motor too!

never had a problem and i still run bog stock high milage bottom ends straight from an importer

it only failed due to a fuel pressure problem and running lean the pistons overheated most likely from detonation and all that happened is it scuffed them all up and pinched the rings. eventually eating out a little part of the piston down to the top ring and it started blowing oil and smoke etc. roda and bottom end were all perfect

[al167]

maybe the vvti rods are weaker does any one know forshure?
all six are bent like bananas
i do run c16 at anything over 22psi
hey shane remember my mph is probably down due to the fact that my toyota hiace isnt the most areodynamic peice of machinery going down the strip. lol
and my best mph at 22psi is 116mph and my best mph at 32 psi is 122mph
all i wanted to do was warn people of triing to run high power on stock internals (wich some people believe to be bulletproof in a 1j, (me included) can lead to ruining the entire engine

[al167]

yep. i found my 1jz's limits aswell, 409rwhp at 22psi for a long time + whatever it was used for in japan .

what u gonna do now?

might build a 1jz bottom(forgies and rods) and fix my vvti head(two bent valves)to fit it so i dont have to get new injectors and make new manifolds ect.
dont know exactly what yet maybe even 2jz but thats big $$$$
does anyone know for shure if a vvti head fits on a non vvti block and ifso what needs doing?
i want to get this thing going for powercruise at eastern creek.........but i may be dreaming

[JZA70 R]

Comparing this motor to anything else of its era is bulletproof...

dunno bout you but 500+ reliable RWHP on a 10+ year old STOCK motor well and truely deserves the title "Bulletproof".

Or did you think bulletproof meant 1200 RWHP on a unopened motor?

[EldarO]

my 100k'+ old 1JZ is semi stock, and takes 8K+ RPM daily.

pulls harder than ever a those revs

Elmo.

[Merudo]

my 100k'+ old 1JZ is semi stock, and takes 8K+ RPM daily.

pulls harder than ever a those revs

Elmo.

You think that's cool, my 1G takes 11K+ rpm hourly.... I'm cooler now

[EldarO]

not really, everyone tells me it should be dead?! but its still going strong.

Elmo.

[whatthe?]

maybe the vvti rods are weaker does any one know forshure?
all six are bent like bananas

Oh yeah, and the vvti has higher compression too.... 9.1:1 vs 8.5:1 IIRC

[wilbo666]

Worth remembering also that vvti 1Js have lighter rods than the non vvti, possibly a limitation there too?

That's also what I thought,

Side by side pics / meaurements would be nice

I can measure an non VVTI rod if you want to measure a VVTI one

Cheers
Wilbo

[whatthe?]

That's also what I thought,

Side by side pics / meaurements would be nice

I can measure an non VVTI rod if you want to measure a VVTI one

Cheers
Wilbo

I'll keep that in mind if and when I blow the engine up

[chris davey]

does anyone know for shure if a vvti head fits on a non vvti block and ifso what needs doing?

Does anyone know the answer to this? Someone with an EPC could check if they use the same headgasket?

I would think that they would be interchangable as the block is still the same AFAIK so you wouldn't think that they would want to change it too much.

Stick with the 1j though! I want to see a hiace with a 1j running 10's!

I see what you are saying regarding the aerodynamics but I agree with Shane that you probably are leaving a bit on the table. I reckon if you dropped that converter to a 3500rpm or so and used a 50hp shot of nitrous you would probably still be able to 60ft the same and you would have a lot less slippage in the converter in the deep end.

[al167]

I see what you are saying regarding the aerodynamics but I agree with Shane that you probably are leaving a bit on the table. I reckon if you dropped that converter to a 3500rpm or so and used a 50hp shot of nitrous you would probably still be able to 60ft the same and you would have a lot less slippage in the converter in the deep end.

any smaller convertor and it takes an eternity get it on on boost. i had a 3200 stall convertor before wich was great with a t3/t4 turbo but when i put the 35/40 on it was practically undriveable with only 3200 stall even with the .63 housing.
the 35/40 comes on at 3600 rpm with full boost by 4000
now the car is, sorry let me refrase that ; was really driveable and you could put your foot down and 2 seconds later your at full boost. i hate lag couse you cant win a race when you have to sit on the line for 5 seconds stallin up!!!!!!!!!!
maybe my car is extra laggy than an older 1j ????????
my vvti is switched off and it wouldnt be making the low end power that it should to slip the convertor till it reaches boost
i was a bit anoyed that the microtech LTX12s ecu couldnt control it.

[chris davey]

Oh I know all about incorrect stall speeds. 13.35@114mph with a 2.37 60ft I see what you are saying and it basically comes down to if you want to run nitrous or not? Like you could go to a 3500ish rpm stall and bit of nitrous and run 25psi to make about the same hp at the flywheel but put more of it to the ground through the tighter converter.

Just a thought anyway.

What diff gears do you run and what size tyres?

[BTM]

With a 9 inch diff and C4, the motor is probably making substantial power at the crank. The drivetrain loss would be huge. So maybe the rwhp isn't a true reflection of what the motor is putting up with....