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NA-t vs gte

17K views 62 replies 13 participants last post by  Maki 
#1 ·
I just want to know people opinions based on their experiences. Which is the most reliable and cost effective way to turbo my vehicle (1st gen is). My goal is only about 350hp. I understand about buying quality turbo parts and all. I know it will take me a little time to piece together all of the parts but I don't have a problem building slowly until I get all of the necessary items to complete the vehicle. If someone would tell me about their experiences between the get and the NA-t builds it would be much appreciated.
 
#2 · (Edited)
Good lord.

You are gonna get arguments both ways. Some people prefer the GTE because it's in a soopra and some others prefer NA-t because they know the engine they have. It's really more of a preference thing rather than a one-is-better-than-the-other thing. Search around, this is known to be the most common question in history.
 
#3 ·
Another main question would be how hard is it to find parts for the aristo engine? I'm guessing non of the Supra parts fit on the aristo? I've done a bit of searching and hear mixed reviews. Pretty much what you said, to each their own. Just would like to know the benefits of having the gte.
 
#12 ·
Not sure if you want to go this route but I picked my GTE internals up used for cheap $130. Some one was selling them in one of the FB groups. I had them looked over they were fine. To freshen them up I had new GTE rings and bearings installed along with new arp rod bolts.
 
#13 ·
When you installed the pistons and rods, did you do anything to the block or cylinder walls or did you just get the pistons and rods and install new rings and bearings with ARP bolts?

Originally Posted by cleansleeper
No head gasket. That drops the compression too low in combination with the pistons and makes the engine far too under powered for off boost driving. As far as price it depends. I got mine brand new from a member and I think I paid $700-900 or something along those lines.
So you can use GTE internals on a non boosted GE motor with a GE Headgasket, but you should use a GTE headgasket if go boosted on a GE motor?
 
#14 ·
When you installed the pistons and rods, did you do anything to the block or cylinder walls or did you just get the pistons and rods and install new rings and bearings with ARP bolts?



So you can use GTE internals on a non boosted GE motor with a GE Headgasket, but you should use a GTE headgasket if go boosted on a GE motor?

No. Don't use a GTE head gasket at all. GE is fine and leaves the compression ratio somewhere around 9.3:1 or something like that. GYE head gasket drops it into the low 8's leaving it lacking power off boost.

When you put the new rods and pistons in have the block line honed for straightest and decked.

Depending on power install new ACL race bearings all around or new OEM bearings. ARP mains and head studs are a good idea as well.

However you will have to grind some inside the head when doing the head studs on a GE head. Its only on one or two but jus be prepared. The problem is the head on the studs and having to get a socket on them and torque them down... there's simply no room in a couple spots.
 
#16 ·
Honestly if you are going for 350 hp you don't even need to do internals. Its always a good idea, but you can keep it stock inside to get the most out of your car off boost due to the high compression. That is what I'm doing. Once the clutch and tune is done, I plan to put a meth injection kit on it to cool combustion temps to help guarantee the engine runs fine pushing that much power on stock compression. My .02.

Edit: though to be fair, the gains by keeping stock compression may be negligible. Doubt it makes enough of a difference to really justify it but you never know. Not to mention if you ever want more than 500 (and thats pushing it) you will have to upgrade to gte internals.
 
#18 ·
#19 ·
I had a book typed out on engine building but came to a simple conclusion:

Most new owners/builders are looking for drop in parts. If the power goal necessitates stronger internals, nothing beats a brand new factory-built short block. Use the GE head gasket for better off-boost response.

Imported Japanese/Junkyard pick-and-pull engines are a gamble.

The end of any story: The harder you work the more you get.
 
#20 ·
A few of the important reasons to go GTE for me:

**Larger coolant pipe around block on the GTE. The GE pipe is smaller diameter
**Exhaust valves are sodium filled on GTE. More important on sequential type setups or track type events.
**Valves on my GE head were shrouded and would be create hot spot in chamber under high boost
**Oil return already supplied
**Oil feed already supplied
**Oil cooler already installed
**Coolant feed for turbo already supplied
**The stronger rods obviously already installed vs the VVTi GE
**Intake manifold and throttle body already on the correct side for proper FMIC.
**Shitty machine work locally has resulted in numerous head gasket failures at high boost.
**I just did maintenance and dropped it in = much less work.

For 350hp, just go with whats cheap.

If I wanted to push it to 600-700hp and not actually build the motor, I did and would continue to take the risk on a used GTE until these things just get too old that everything used is crap (eventually heading there as these age)

If I was going to build the motor anyway. I would start with GE, upgrade pistons, rods, oversize valves, do head work including cleaning up the sharp edges in the GE head, fix the smaller coolant pipe, install an oil cooler, go to a different intake manifold, etc. etc.
 
#22 ·
It's funny seeing people say you can just Drop in a GTE engine. Is this your first car boosting? How experienced are you ? Are you planning on having a shop do all the work for you? How much are you willing to spend? Don't get a piggyback. And don't just assume everything will work perfectly.

This is my first turbo build. And I only make 310 who on 6 psi of boost with a PTE 6262. My original goal was 350. Now I want more and I have a second engine on the side that I'm building. The current engine now has basically one dead cylinder. I have ridiculous blowby and it misfires on cylinder 6 quite frequently. I was very inexperienced going into my build and it cost me an engine. Building your car is more than just reading on the forums and through the service manual. It's about getting your hands dirty.

Now if you're already a mechanic that's confident in what they're doing then just dismiss what I said.
NA-T ftw.
 
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#23 · (Edited)
The GTE will drop unto the engine mounts and that's about it, it is by no means plug and play. There's some minor engine bay modifications and who knows how the engine's been treated. There can be all sorts of problems (valves stem seals, turbos, without going into the wiring nightmare) and the average joe is not a shop owner who has exactly every tool necessary. It only follows there will be labor costs which are not cheap. I mean, you choose what to believe in I guess, and we all firmly believe we will not get screwed, but I had all three of those problems. Thankfully I have a job that pays well but still, too much money down the drain, had I been a high schooler or college student I would've been walking to school.

Anyways, your experience has been cool. I learned my auto mechanics on an old 4 cylinder engine. Took it apart and put it back together and that was as much fun as I can remember.

P.D. I've had 2 non-turbo cars which I have modified for FI. Never again will I do it. It is so much simpler to buy cars that are already engineered for such setups....then again....you CAN buy IS's for 4k nowadays and they are 4dr supras :grin:
 
#24 ·
The problem is that the same goes for the GE, about all you end up leaving stock on it are the motor mounts and then also need to add items above, and a GE is likely to be just as labor intensive or more if you are talking about swapping pistons, etc. This car was not meant to be easily turbod. I think you hit the nail on the head as far as it is just easier to buy a turbo car and neither route is for the faint of heart on this car.

I wouldn't feel like you got boned on your motor as those are basically maintenance items, just like the timing belt, cam and crank seals, etc.. The valve stem seals will for sure be dried out and hard as a rock on any GTE at this point. The only reason they won't smoke is if they were already replaced before you got the engine. Turbo seals may be intact, but any large exhaust on your part or previous owner will cause them to smoke or die (need some kind of restriction in exhaust with the stock turbos). You can usually find another set of questionable stock twins for $80 if you are trying to be cheap.

I'm not sure what is a nightmare about wiring if you use GE harness and GE ECU. The GE harness plugs into all of the sensors. Just go one by one with the sensors, unrwap and reroute a few, and then extend the others.

Time consuming... yep...

costs more money than expected... yep..

fun... yep..
 
#25 ·
For the wiring....I forgot to mention I kept the Aristo ECU, it was a pain and it took the shop that did it quite some time to figure everything out.

At this point I guess we can just agree that it is a matter of preference. As I have had semi bad luck (let's meet halfway.....) I could've turbo'd my GE (knowing that I had taken good care of my engine) and done more actual modding for the money I've spent.
 
#26 ·
PnP harness are available to merge the two ECU's.

My goal was always 600hp. I drove on the auto trans with 400hp and stock internals, swapped to a manual trans, forged the block and am now at 500hp. Still aiming for 600 but after that, I'll probably want 700.
My reason for building the GE is that I wanted to pull the engine only once.
 
#30 ·
you'll have to do a lot of work to make stock ecu happy with a different motor.

I have passed emissions with a standalone and a piggyback, and it's hard.

if you want simple, just boost it to 7psi sock everything except and a fuel return and an adjustable rising rate fuel pressure regulator with a big fuel pump. i've seen 350 hp out of it and it will pass emissions with easy driving for a while. passing emissions in a highly modified car is just flat out difficult. You have to know how to drive, you have to monitor all the fuel trims, cats, evap constantly.

it's a bear
 
#34 ·
In Nevada they just plug it in. If no check engine you're good. That's assuming you are OBDII
 
#56 ·
I don't think the info on the forums is dated. Just not a lot of info on the new stuff, doesn't mean the old stuff doesn't work. You just gotta talk to the people that have turbo IS300's already. They will lead you in the right direction.

I paid $800 for my MS3 Pro with harness.
 
#63 ·
I went the GTE internal route and I love it. Did a full build on the GE and scooped GTE rods and pistons for around 400-500$ new, had all of it balanced and assemble by the pros. When you see the GE and GTE rods laying next to each other on a table you will realize boosting the GE internals is a very bad idea. They look like toothpicks compared to the GTE rods. I also run a Micro-Squirt as a piggy back and have zero issues or codes. Granted it took a good bit of tuning time to work it all out (aka money). I highly recommend to not just slap a turbo on the stock motor for peace of mind at the very least, it is nice not having to worry every time you spool if your motor will hold up to it.
 
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