tpham86

iTrader: (1)

wtf? where did you get that it makes 400ft lbs at 2400rpms?

account2x

iTrader: (5)

The 1JZ-GTE's head is designed to flow a 2.5L engine. The 2JZ's flow is higher than the 1JZ for the 3.0L engine. Intake manifold included. 3" Throttle of the 2JZ versus 2.75 (I believe) of the 1JZ.

The engines ability to rev safely comes from the stroke. Stroker stroke = more rev happy.

Most 1.5JZ builds use the 2JZ-GE block. The GE block is missing the piston-cooling oil-jets of the GTE block.

I understand fully why someone with a 1JZ would want to go 1.5JZ but objectively speaking a 2JZ-GTE swap makes more sense.

88supramki

if you think about it, it's not the head that makes the motor rev to 7500. it's the stroke of the cylinders. The 1.5JZ is kinda like communism, good in theory but flawed in real life.

soardrft

iTrader: (8)

So your argument if based on matching motor for motor.

To help others on this forum. 1.5jz is not a bad idea. The reason why people go that route is due to already having the upgraded accessories for the 1jz (single kit, standalone, etc..) It is cheaper for me personally.

As for the oil jets. Yes GE blocks do not have them, but they are not really needed. Yes they cool the pistons and gives the owner more reliability, however you will not notice the difference if you had them or not. Perfect example are na-t guys. Again plenty of 1.5jz guys don't have them.

2jz compared to a 1.5jz has yet to be determined. Unfortunately my original 1.5jz was suppose to prove 1.5jz's power, however I did a full rebuild and installed for a fraction of what a true 2jz would cost. However there Is another 1.5jz out there (google) stock everything that put out 387hp.

88supramki

We aren't saying that it's a total crap motor. We are saying that it's not the "Ultimate Holy Gail Motor". Sure it will work just fine, but again you run into the argument of uninformed people who say "It's got a 1JZ head so I'm getting a 2JZ with a higher rev limit!"

account2x

iTrader: (5)

All things being equal the 1.5JZ won't put out as much power as the 2JZ because of the more restrictive head. Intake manifold as well when stock.

A 1JZ is a fast-revving, high-revving engine. I wouldn't say it's flawed but purpose built. If one is looking for a drift engine the 1JZ is a clear winner over the 2JZ. But a 1.5JZ is the worst of both worlds. This is why it's a bad idea.

Increasing temperature in the cylinder helps promote detention. Cooling jets reduce cylinder wear and allow for timing advance.

Cleanshots

iTrader: (2)

there is a 3.4L stroker on ebay right now for like 2500 cams and all..
http://cgi.ebay.com/ebaymotors/2JZ-G...item2c5cd60e94

mr/griffin

its dyno time! i want to
1. 2jz stock dyno (yeah i know)
2. 1.5 tt stock
3. 1.5 vvti stock
4. 1jz tt
5. 1jz vvti

ps 1j has larger exhaust ports than 2jz but smaller intake ports

this is for all the smoke blowers posting opinions as facts










0

mr/griffin

sounds like a scam

88supramki

Don't know anyone who has actually had the desire to do this. people ditch the 1J block because their either have a desire for higher HP or they have an issue with the block. the 1.5 vvti is a waste of time personally.

With smaller intake ports wouldn't it be harder to force more air in by using a 1JZ head? Physics + Basic Shapes = right answer.

soardrft

iTrader: (8)

And this is why I am taking the time to speak up. 1.5jz has potential just like every other motor (we should all understand this). Contrary to popular belief it is cheaper than a 2jz, but stronger than a 1jz.
Unfortunately I am knee deep in creating data on the pros and cons of this motor.

Thus far I can say cooling jets are the least of my worries. Going back to the example how many na-t's run large numbers without them. They are in place to prevent and we all know that, but na motor can hold the same if not more power than the 1jz (theory)

Now about the 1jz. Great motor, but once you go single you have lag.period no way around that so far unless its vvti but yet to be proven. Compare it to a 1.5jz where it capitalizes on where the 1jz lacks. Yes, 1jz you have a longer rev, but torque drops off at 6500. So the longer rev its not really beneficial. Another reason why 1.5jz is comparable (more power band to play with)

As for the 2jz well I will just make this simple. 2jz in many cases is better, but for the price 1.5jz is cheaper.

But one thing that is not clear is what cam selection to go with on 1.5jz causing this debate to be relevant. If we could say usdm cams with a 1.5jz 440s that would equal close to 400hp (that's been proven)

88supramki

^^
I thought that the 2J cams wouldn't work in a 1J head? I could be wrong though.

soardrft

iTrader: (8)

Machined to fit $80 at most

account2x

iTrader: (5)

Cheaper needs to be defined. A 1JZ auto is 1000. A 2JZ auto is 2000 dollars. shipping excluded. Of course both engines can be found cheaper but this is the eBay going rate most will pay.

A great advantages of an engine swap is all the parts that can be sold. The rear sump oil pans off a JZ are worth 300. Block can be sold for 100. The GE rods and crank another 100 and so on. I think it's fair to say you can get 400 minimum for your old GE engine.

A 1.5JZ requires the head-gasket and studs to be changed. Add a minimum of 100 for this operation in parts. I forgot 1JZ also comes with 330cc injectors aren't even really sufficient with increased boost. 1JZ people also get 2JZ cams and regrind them. Let's be generous and say an extra 150 for 440cc injectors and 2JZ cams reground.

The 2JZ has a 3 inch throttle-body compared to the 2.75 of the 1JZ. The head flows better. It has oil cooling jets in the block because the block is GTE and not GE. In my opinion and I know this has nothing to do with performance but the valve covers just look better.

In conclusion when looking at all the factors the 1.5JZ is at best marginally cheaper than the 2JZ but stock of modified it's inferior. But looking at the cost benefit analysis we can see that the few hundred bucks spent extra on the 2JZ-GTE are well worth it.

soardrft

iTrader: (8)

Great point, but how many members bought a 1jz because they did not want to spend the extra for a 2jz. And out of those 1jz members build their motor. Now if they kept the bottom end they would yield more power than what they have. Plus they could also take time and build it to be better than the slap on job we were debating. Thus leading us to why the 1.5jz is a great idea and cost effective