I though this "NA head flows better than TT head" myth was debunked long ago. I actually started doubting myself after seeing all these recent post here and on supraforms about the NA head flowing better so i decided to do some research.

I do not have hard data but i gave headgames (for those who don't know, they do awesome work on heads and is well know in the supra community) a call and the person i spoke to confirmed with me that even though its not by much, the TT head still flows better. Since both heads use the same size valves, the flow between the 2 are going to be similar but the TT head does in fact flow better according to the person i spoke to. I also called portflow but they never flowed a stock NA head before so they couldn't answer the question. There were also flow numbers posted on the suprafourms that showed the TT head flowing better than the NA. unfortunately the search function on SF doesn't work so i am unable to find that thread.

I believe you are spreading some misinformation as well. Your numbers are inflated and give people who are not as knowledgeable the impression that these engine will make these power levels all day everyday. The highest stock bottom end GTE dyno is 980whp which is no where near the "well over 1000hp". Dave H has never made 1000hp on stock GE bottom end. Below is an email from him regarding his setup in his red car. In his own words, the car MAYBE made 800rwhp at the highest point .

 

He didn't say wheel horsepower. 980whp is going to be well over 1000 crank horsepower.

 

1) price: You get what you pay for
2) availability of parts and upgrades: Parts are expensive but that's what a 2jz-gte is about to me
3) reliability: Reliable enough
4) uniqueness : Doesn't have to be
5) out of the box power : Almost limitless
6) potential : Legendary

 

Ive been trying to decide between a 1jz and 2jz. I think from what Ive read about both swaps, Im going with the 2jzgte. Ive already got my r154 tranny swap together, so its about time to order an engine.

My plan as of right now, is to get a clean Aristo engine from an importer in Houston ($1800). Only 4 hour drive, so I can save on shipping.

Ill be putting a single turbo, and changing the injectors already so that stuff doesnt matter. Ill use my GE's oil pan. And, a friend of mine works at toyota and will give me his discount on a Supra harness. Then, a used ecu, ect... Seems like the best set up for my goals, anyway.

 

Ok, i didn't know people quoted crank hp? On every automobile forum im on, from domestic to import, whp is always used. He did start off by using rwhp so i figured that what he meant. However, i have noticed that BMW owners prefer to use crank hp for some reason .

 

I made a thread about this but I didn't a clear answer. I want a 2jzgte. My car right now is a 98 w/ vvti. I was thinking about getting an engine w/o it because that's what the general consensus is here. But after reading this thread, it seems like vvti would be better and one of the only things I'll need to change are the internals. Does this sound right?

 

Just thought I would take the time to share my current stance on the topic:

(1UZ-FE) This engine is luxurious and buttery smooth in its power delivery. It is very difficult to modify since there is little in the way of mass-produced modifications on the open market. If you have some patience and determination, and you are looking for both performance and uniqueness, running a forced induction set up on this engine is for you. Mild set-ups can make 300-350whp and retain stock reliability. Wild set-ups offer huge potential with the 4L of displacement; but the cost is steep to very steep.

(2JZ-GE) If your motor is healthy and you are looking for performance -even in the 500+whp range- turbo your stock motor. With a little turbo savvy, you can throw together a set-up rather cost effectively. There are even full kits in production that will practically bolt on. Regardless, the stock bottom end can take a pounding.

(1JZ-GTE) If you are in need of a swap, the 1JZ can be the easiest option since a Soarer harness can mike wiring a breeze. Scrap the stock twins and go for a 60-63mm (maybe even slightly larger) turbo, and you can get really nice power with good spool. 400-450whp seems to be a drop in the bucket for the 1JZ. A 450whp/375wtq engine should still be able to work with your W58 trans so long as you upgrade the clutch.

(2JZ-GTE) If you have major power aspirations, this is your engine. Weed through the myth and folklore, and you will still find stories of stock longblocks churning out 500++whp for many tens of thousands of miles. With a 2JZ-GTE, my mind is thinking race gas and high boost right out of the chute: the engine is just so darn capable. Even a mild set-up (63-67mm turbo) on pump gas will torch the road at 18-20psi. Initally more expensive, the 2JZ-GTE will likely begin presenting value over all other engine options if you intend to take the engine past 500whp.

 

Understandable, but if we're talking about what the motor itself can hold, it makes sense. Wheel numbers are going to vary, the same motor is going to put down more to the wheels through a 6-speed than it will through a stalled auto.

I'm not arguing with you, just trying to further the discussion.

 

Interesting thread. Here's what I'd do -

Since nobody seems to realize the only significant difference between the 2JZ-GE and 2JZ-GTE short blocks is the under piston oil squirters, I'll state it for the record - they are identical except for this. Yes, the pistons are different, but changing pistons while you have the short block in the stand is pretty simple unless you plan to use gapless rings, but that's a different subject.

1JZ rpm advantage? Fine. I'll still take displacement over rpm in this case because I can rev the 2JZ to 10k rpm if I'm willing to suffer the reduced service life. It won't blow up if the head is built properly.

AFA the heads - it sounds a lot like nobody here has actually stuck a die grinder down a port. I've done both GE and GTE heads. The GE head lack the cooling of the GTE heads, and the GTE heads have all screwed up exhaust ports. The ideal head is the GE intakes raised and widened a few mm then blended with the floor of the exhaust ports welded up ~4mm to flatten it out and raise them then add the GTE cooling passage over the top of the exhaust ports. So, that head doesn't exist in real life. But the intake ports would look like this:





(This is my work, not some shop. There are bigger pics in my photo album, and this head belongs to someone well known in this thread)

Ideally this head would also have 1mm oversize valves on both sides and 85% port to valve diameter ratios. The GTE head likes 88% on the exhaust for some reason, but I think it's because the GTE exhaust ports are not as nice as the GE's. JMHO.

So, in the end, I'd marry a GTE short block to a GE head modded similarly if I wanted best power and good reliability. The extra cooling provided by the under piston oil jets makes tuning a little less scary, and you can run ever so slightly leaner without disaster, so if you make a small tuning mistake it won't cost the whole engine. Finding a junk 2JZ short block worth rebuilding isn't too hard - I've got one in the garage right now just waiting for the time to do it. The head work is pretty easy, and bolting it all together isn't hard either.

I haven't played with a VVTi head yet, so I really can't speak to any advantages or disadvantages, but I will say one thing - thick headgaskets are the kiss of death. Spend your money and change the compression the right way - put in the right pistons. Thicker headgaskets only increase the squish volume and reduce detonation resistance. Ideally you want the top of the piston ~1mm from the bottom of the head at TDC, and maybe even less (GSXR 750s seem to like a little less than 0.5mm for best performance!) but the whole reason for this is to reduce dependence on band aids like water/methanol injection for killing detonation. They have their place, but if you get the engine's internal dimensions right the first time, you'll get far more from plain old pump gas than you ever imagined possible.

BTW, I just read some serious misinformation about the compression on the GE and the GTE being determined by the headgasket. Nothing could be further from the truth. See pics below:





Notice the step in the head around the combustion chamber on the GE head? That doesn't exist on the GTE head as you can see in the lower picture of the GTE combustion chamber. The bottom of the GTE head is flat with no step at all. Also, the combustion chamber volume on the GE is significantly smaller than the GTE. Notice the shrouding around the valves on the GE head that is not present on the GTE head. This shrouding takes up a lot of room and raises compression ratio all by itself. Both are terribly limited in the squish area department and this is why the more modern engines have better specific output (more compression, less detonation problems), but the combustion chambers are just as different as the ports are. FWIW, this GTE head is a true street port - not pretty, but very functional and intentionally left rough for post-portwork ceramic coating.

You also might want to peek at this before you start fussing with your 2JZ head. It might save some time and money, and I'll stand behind everything there because I wrote it.

And the bottom end on the V-8 is nowhere even close to the J series engines for strength and reliability.

 

I wish you lived in MD

 

Well folks do it right and do it once lol. I went from 2JZGE to BPU1JZGTE to APU1JZGTE and now I'm about to pull the 1J and go BPU2JZGTE ha ha. All this time and money I could have built a nice na-t setup or bpu gte setup. So in otherwords with the availability of jdm gte aristo motors going 2jzgte isn't as expensive as it used to be. Do it once and do it right go 2jzgte.

 

Is it just me though or did the wiring difficulty related to the GTE swap suddenly dissapear? I thought that was supposed to be hard.

 

It should be available in that 2jzgte swap manual. I'm sending my wiring off to Dr. Tweak in GA here's his site www.phoenixtuning.com

 

How much $$$ does it cost though?

 

Lance,

I applaud you for taking the time to type up that information. There were a lot of things included in your post that im sure that many people can use.

For the sake of discussion though I wanted to point out to you that the staggered cam theory was proven incorrect with dyno tests by a company that posted up on SF. They tried it with some mismatched 264s and 272s and with the cams as a matched set. They got better results with the matched set.

what is the piston deck height of a 2jzgte? I would really like to know that so that we are comparing apples to apples.

What is the cc volume of the gte vs the ge head?

I dont really agree with the context you put this into - It certainly isnt "misinformation" or "nothing further from the truth" although it does not include the fact that the head is shaped differently. The head gaskets and pistons are different. I have to give props to Bean for his writeup. Taking the time to explain something that has got thousands of views is something that not a lot of people care enough about or have the knowledge to do.