if money isnt an issue, then yes go 3.4. i dont know of anyone running a 61 or 67 on a 3.4, but i would think you would want something a little bigger than that.

 

3.4L motors have an 87 mm bore, the same as many built 3L motors. The rest of the displacement increase comes from the increase in stroke from 86 mm to 94 mm. Piston speeds increase but, yes, on drag and mile cars, 3.4s have revved to 9,700 rpm, possibly higher, with undisclosed oiling changes and whatnot. Those cars need the revs, though, to move those huge 91 mm turbos.

It's important to remember that a 3.4L motor makes the power you make more accessible. There is no need to rev the motor to the heavens, as many believe is necessary, for any turbo 80 mm and under, IMO. I made 1115 whp at 7,200 rpm (twin HKS GT3240s), for example. In your case, with a very small 61, or even a 67 mm turbo, the 3.4L will give you instant spool and will take all those turbos have to give, and then some, well before you reach the factory rev limit (with proper tuning). Talk to Ryan Hawkings. He has a 3.4L/61 mm auto and can give you the benefit of his experience.

Ken.

 

Never a good reason not too other than cash concerns.
Stroke that thing!

 

More displacement = quicker spool for the turbo.

 

This may or may not be true - but since the clearance and tolerances are so tight and low, I've read and heard that the 3.4L builds just don't hold up to abuse as well - Displacement is great, but I would think a built 3.0L is going to hold up better?

I'm hoping not to have to find out - but if I ever have to replace my stock 2JZ I'm not sure I'd go with a stroked kit.

 

^^^^^^^^^^awwwwwwww shit, now you done opened up a can o' worms^^^^^^^^^^^^


:drama::drama::drama::drama::drama::drama::drama::drama::drama::drama::drama::drama::drama::drama:

 

Well I'm happy to be wrong - but logic dictates, bored material means less retaining material - I suppose you could argue that because a bored/stroked motor makes power sooner that it doesn't have to be driven as hard, I don't know...

Again, for me if I ever have to make that decision I am not sure I'd do a stroker because at the end of the day I need a 100% rock solid OEM reliable engine, so short of needing to make 1500whp I'm not sure I'd have a good reason to.

 

oh, no, please dont misunderstand me, but every time i get into this discussion it always seems to get ugly. im just interested to hear what people have to say. id like to be a bit more knowledgeable about it myself.

 

um, ill say if 3.4L for you is a foundation for your future big HP mods, plus money is not a issue for you then go for it. you will gain higher rev and much quicker spoolin in one hand. In another hand, the much quicker spooling may give u a real hard time to drive. IMO. so, why dont you wait till you geting a bigger size turbo then do it in one shot.

 

I suspect the normal owner who chooses this upgrade path is doing so to obtain the most available power from the 2JZGTE. It's a costly upgrade but the rewards pay off when trying to spin a larger turbo.

I have only seen one individual to date who purchased a built 3.4L motor with the intention of running a smaller turbo. In this particular case, the individual was running a 61mm turbo. The car was located in NZ, so I never heard anything in regard to his feedback on how he liked the setup. I do know that the individual was selecting this path to extract the most power under the curve and torque because he was planning to road race the car.

With that said, I can only imagine the thrill of a driving a Supra with a built 3.4L coupled with a fast-spooling billet turbo like a 6265 or 6765, or any of the new smaller Airwerkes turbos. You would have a car with excellent spool characteristics, great torque, good driveability in vacuum, and good reliability. I can imagine this kind of a setup would be a real blast to drive around.

Heck, I bet a built 3.4L with appropriate mods and a billet 6765 would spool like billet 62 car, and make 850-900whp on E85..... THAT would be fun.

 

yeah and don't take my word for it - I am just saying what logically makes sense to me - I too would love to have a higher displacement car but if I have to give up 10% reliability for 10% displacement, I'll take a built 3.0L (or 3.1 or whatever they end up being) all day long...

There just isn't a lot of room to stroke and bore the 2jz, I mean a stroked and bored VQ can gain almost a litre, and for us the most extreme builds push it to 3.4 - seems like a very very expensive way to gain 13% displacement - and when I think about it, a 3.4L engine should NOT be as reliable as a 3.0L just based on the loss of retaining material - I could be completely wrong though...

 

Honestly, the bore increase isn't an issue; it's the increase in stroke. One can assume more force on the rod bearings due to increased leverage. However, I would argue that a motor that wasn't routinely stressed with high RPM's would likely never see reduced reliability if you simply lowered your rev limit slightly. I don't think there's a lot of data available on 3.4's that are just sublimely street driven and pushed on occassion. With a proper rev limit I don't see why a 3.4 properly clearanced wouldn't hold up just as well as a built 3.0L counterpart.

I suspect the vast majority of the 3.4's out there are pushed to their limits; not just driven around. I know one individual who drives a "street" supra on a 3.4 and has done so for the past 4 years with aboslutely no issues. His particular car makes north of 900whp when it's asked to do so, but tools around like a daily driver with no issues.

I wouldn't hesitate to drive a 3.4L, but I'm also not going to rev one like a 3.0L if I want to depend upon it for good reliability.

- Hams

 

Ken,

This is mainly street driven car. I have a dd now but the only track I would want my car prepped for is a road course. What would you recommend doing now know this?

Also I have a 61gt tuned by Justin Nenni that has been amazing to me I make over 500whp on pump gas at 17 and have great drivability. I honestly don't care to increase power that much as I was very happy with the power-band with the 61. I am mainly doing this b/c of the age of the motor and the fact that it is at least due for a total seal replacement. So I figure might as well make sure I do it right once

Any advise form people with real world experience would be great.

Thanks Again,
Anthony

 

man if you're just in need of seals I'd spend the few k to have someone do them, and maybe refresh the valves and springs while you're in there - going 3.4L is an extreme way to spend lots of money and an extreme way to just refresh the engine

 

Ken:

I greatly respect your experience and input, but having 10k miles on a stroked engine in 6 years is hardly what I'd call a street driven car - I put 25k miles on my cars annually, in fact in the past 6 months I've put more miles on my supra than all the miles on blackie since the stroker went in.

I have a hard time quantifying my statement that a built 3.4L should be LESS reliable than a 3.0L but logic dictates (at least in my finite mind) that less material and more stroke would mean less room for error, and less tolerance for abuse.

I don't know dude - If I replace my stock engine, or rebuild it - I want to know it's going to be reliable for another 140k miles (or for another X miles depending on how long this one continues to last!)... Also, from having had built motors in the past, I can definitively say that they are NOT all it's cracked up to be - every built motor I've had in various vehicles has been temperamental, built to far lower standards than OEM engines, tended to eat oil, and were just louder. I perfectly understand your need for a built motor - you have a purpose built machine that is capable of 1200whp - something that is not capable on a stock longblock, but if the OPs goal is 500-600rwp, I feel fairly confident he can do that and put a 100k miles on a stock longblock and a small turbo - when going to a 3.4L might spool his turbo a bit sooner, the risk may be greater than the reward for a relatively small target?

-Zach

 

Ken:

I greatly respect your experience and input, but having 10k miles on a stroked engine in 6 years is hardly what I'd call a street driven car - I put 25k miles on my cars annually, in fact in the past 6 months I've put more miles on my supra than all the miles on blackie since the stroker went in...

Zach,

It seems that you're confusing 'daily driver' for 'street driven'
Blackie, as Ken has affectionately named his built 3.4L stroker car, sees only street duty when it does go out. Thus, it is a 100% street car, meaning that it's titled, insured, and hasn't made any sacrifices to comfort and for the sake of performance. It's truly a 'wife-approved' vehicle.
But with 1000+ hp on tap and drinking a strict diet of C16/Q16, it's not a car to hop in to just get groceries. When that car leaves the garage it leaves to go play hard - but in SoCal that means a ton of bumper to bumper traffic no matter what, and thus the mileage might not really reflect the time it's spent on the street.
Knowing Ken's tastes and the build quality of cars that come out of SP Engineering, I'm sure with a pump gas map that 'Blackie' would quite readily drive daily for any commute.
It's a simple matter of taste, and the presence of Ken's Red BPU Supra that make it unnecessary to drive it daily.

As for the 3.4L's reliability record, throughout all the concern for the 3.4L's longevity I've not ONCE seen any sort of empirical evidence or a first-hand account that proved or even made a reasonable case to support the idea that a 3.4L 2JZ is inherently less reliable.
As with any built engine, there's concern for whether or not it was properly assembled and assembled to the correct specs, but outside of human error in tuning or engine assembly I've seen nothing to substantiate that a 3.2 or 3.4L 2JZ wouldn't do 100+k miles of happy boosting just like its OEM 3.0L counterparts.

 

fair enough... Street driven and daily driven are far from the same, I'll concede that for sure.

and I certainly am not questioning the quality of his build - but the OP flat out says he plans to hit a few HPDEs and is only targeting low 500 whp, Even if all other things are equal, let's assume a 3.4L is just as reliable in everyday situations - Is it worth the 10-30 grand it would cost for a relatively low. So rather than speculate - let's go with what we KNOW

we know there are LOTS of people with 500-750rwhp stock longblock cars that routinely see 100+k miles, if Ken's assumption is correct and he has the highest mileage stroker in existence - that to me would indicate there is just not any empirical evidence to suggest that it WOULD hold up that long either....

Please don't misunderstand me, I'm not knocking the 3.4L builds at all - but my interpretation of the OP's OP is that he's concerned about longevity as well a low over all HP goal that would make a 3.4L a bit of an unknown and prohibitively expensive given the risk, and unknowns.

-Zach

 

Zach,

Your experience with built motors is exactly the opposite of mine. I would suggest your experience with built motors has been less than satisfying because your engine builders have not been up to snuff. I have an engine builder, that is also my tuner and my fabricator. There is also port and polish experience on staff, but that work is only done on the owner's cars. My built motors have never smoked, acted temperamentally, drank oil or did anything other than provide me driving bliss. I sold my built, 3L shortblock to a good friend and he's put more than 70K miles on it since 2004.

I didn't realize daily driving was the standard you were using. My black car is not daily driven, but it certainly could be. The HKS stroker comes with a billet crank, Carillo rods, coated HKS pistons, OEM oil squirters, an oil drive gear and the like. Assembled and maintained properly, there is absolutely no reason for the motor not to last virtually forever if driven in the same manner and making the same power as a stock block motor. But, no one builds a stroker to putt-putt around (not saying that you do). Guys build strokers, generally, to make big power. More power means more stress on all parts so, unless you are going to limit yourself to your stock block driving habits and power levels, a built motor, whether 3L or 3.4L and driven as God intended, is going to be less reliable than a stock block motor not routinely driven to its limits.

You've mentioned the 87 mm bore issue on several occasions, assuming this creates a reduction in liability. First, from my own personal experience, this is not the case and, second, many built 3L motors already have 87 mm pistons. I know I did, so my increase in displacement came solely from the increase in stroke. I may have a bit over 10,000 miles on my motor, but that is why I mentioned the more than 25 1000+ whp dyno runs, the bike racing and the dreaded SoCali bumper to bumper since, other than the bumper to bumper, it is not likely you subjected your OEM stock block to such stress (I could be wrong, but this is what I have gotten from your posts). It's my opinion that there only a few really good Supra engine builders around, notwithstanding the plethora of Supra shops. Finding a good engine builder is the same as finding a good doctor, lawyer, CPA and the like. The price is extremely steep if you fail in this key step. Best of luck with your decision.

Ken.

 

I won't say that my experience has been less than satisfying, but you do make your experience sound like rose water and chocolates - that doesn't mean that my engines haven't held up to a lot of abuse, and that may be why my experience with built motors is tainted because when I've bothered to do so it was for the purpose of beating the piss out of it ;P

I still contend, your considerable wisdom here not being disregarded, that for the OP a stock longblock/refresh fits the bill nicely and there are literally hundreds if not thousands of examples of the stock longblocks holding up to the relatively small power levels discussed here.

I just finished my build, and I literally TRIED to aim for 450-500whp, and ended up with 604, 599ft/lb - the car makes more power than I expected to have on just spring pressure - the point though is that for a supra we're talking about absurdly low power on a motor that will put up with unheard of levels of abuse...

I probably *AM* that guy that would daily drive a stroked car, and I would drive it like I do my current stock engine - so it might hold up to 140, 150 or 200k miles - maybe I'll be the first one to find out - It's the sledgehammer approach though when a peen hammer would suffice.

-Zach

 

I feel at the power level you've claimed to want. keep the stock block, save your $$, and buy a spool valve or the like.

It'll spool up quicker, and give you the results as if you had a stroker, but without the pricetag. And if you DO blow your motor, up, you can just buy 3-4 more stock 2JZs and keep dropping the stock ones back in.

No fuss, no muss.

This being said because you said you wanted reliability over power.

Jeff

 

Some info on me, my car, and some experiences I've had with it to help you guys understand what I'm trying to achieve and get your opinions on how I should do it.

So I'm not saying 500 is my goal I am just saying I was happy with my power band and that level;. Also I want to have usable power and my experience with over 600whp on the road was blowing the tires out this was on stock wheels with good rubber though. and when the built motor goes in the car I will have my CCW 18x11 on the back again with good rubber of course.(any suggestions on that would be great)

A little more info on the car is it was my daily driver for almost 13 years a real daily driver. It was single for around 5 years and bpu before 5. Finally bought a real DD (06 Subaru spec B) and decided it was time to get the supra in shape started as a clutch job and finished (thought I finished) a little less than2 years later. This took so much due to cutting corners and all the little things I had done and sometimes forgotten to keep it on the road and driving. Being a college student during this time I was on a budget and only put money into the motor. (As all professional tuners do)

So after doing the refreshing of suspension, brakes, interior, and planned exterior which will include the fender widening to fit the CCW properly. I find out before the final step that have a a oil leak (also a miss that wasn't there before the car set I think it could be a ground issue or possibly tuning b/c turbo was rebuilt)at first I think it is the RMS I changed it 2 and still the same leak I changed the lower oil pan during the refreshing so I think it is actually the upper seal the needs replaced.

Instead of over removing the upper pan re sealing it and hoping for the best I decided to either build the motor or get a new short block. The 3.4 with a 67 (maybe the TO4Z never had a HKS turbo before this one seems to meet my requirements)or similar has always been appealing to me. I imagine it would be similar to the power band I have now only on steroids.

My only concern with to much power is traction!. I do not want to get more power than what 11.5" CCW and PS2[s or similar summer tires (not D/R's) can hold down. Usable to me means if I want to accelerate as fast as possible I should be able to keep 2nd gear spinning to a minimum on an ideal surface with good fresh tires on a warm day maybe even use some of first gear and chirp second.

I am unaware of what the CCW's and large rear tires (315/30/18) can actually do for me. Currently my only experience is stockers 275/40(so far my favorite have been GSD3's.) I am hoping for a large improvement with the bigger wheel but am very nervous I really wanted 19's but went 18 for hooking up. 19" sp500 look so good on a red supra (red to me is the hardest color to get wheels to look properly on)

Sorry for the long post I got a little carried away but I have been getting some responses from great members and want to get as much valuable info as I can while I can.

So thanks again guys,
Anthony

 

To be clear, I am not recommending that the OP stroke his motor. My posts were related to those that thought such a build was inherently unreliable and not suitable for DD activities. You can, in fact, build a 3.4L race motor that is rather unsuitable for the street but, if your engine builder is intimately familiar with how the motor is to be used, 100% street in my case, there is no reason why a guy can't have his cake and eat it too when it comes to stroked motors.

Ken.

 

i def agree with you on the cake ken, i do love cake