I'm in the process of boosting my 92 SC400 (1UZ) as I decided against swapping it. I'm currently putting together a turbo kit for it and I really need help deciding on a piggyback. My goal is 500-600rwhp between 14-18lbs of boost.

Parts:

Eagle H-Beam Rods
ACL Rod Bearings
0.093" Headgasket
ARP Headstuds
RX7 550cc Injectors
AEM340 Fuel Pump
GT45 Turbo

Thanks for any help in advance

 

piggybacks are going to be terrible combined with this ecu for a turbocharger.
only one that might work well is an aem fic-8 which you can run in intercept mode and take over full fueling without tricking the stock ecu (the fic can controls the pulsewidth directly after the stock ecu).
it takes a bunch of wiring and is a bit expensive.

what I am going to do when I build a sc400, is run an aem ems v1 or v2 for a supra.
the reason is it plugs into the factory connector, and you only need to wire up a few things that are on different spots on the 1uz pinout vs the 2jz pinout (mainly the 2 extra fuel injectors).
I have heard its even possible to do it with no rewiring just need a custom cal file.

once you set up the calibration and there are threads out there with helpfull hints on doing it for a 1uz which has been done before, you will have full control like you would on a 2jz, which will let you get every last bit of power out of it without battling the stock ecu. and also aem v1 has fallen in price alot its not much more than what some piggybacks cost these days.

the early 1uz has 2 distributors so the aem ems v1 would work nicely even though its wasted spark and only has 5 coil drivers, because an early 1uz only needs 2 coil drivers to work (2 coils for 2 distributors remember).
If you wanted to run coilpacks you could do that also using 4 wasted spark toyota coils on an aem ems v1 as it would only need 4 coil drivers (aem ems has 5).
If you wanted to run full sequential ignition with coilpacks and no distributors then you would need an aem ems v2 which has the 8 coil drivers you would need to do so.

so the only reasons to get the aem v2 are the full coilpack option and also the v2 does flex fuel stuff better if you are into that. also some better options here and there the v2 can pick up the cam/crank a little better but the v1 does fine on our motors.

also you can really use any standalone and wire it up, I only mention that one cause it plugs in and had an excellent price point for what it can do.

 

Down side to AEM v1 - no auto trans control. If you're not swapping in a manual trans, you don't want to go that route.

 

The AEM EMS V1 & V2 look pretty interesting

What would I have to do to install it and how well does it work.

I know currently there is no plug & play standalone for the SC400

 

AEM 30-6100-6101 will plug right into the SC400 harness .SC400 and SC300 from 92-97 uses the same ecu connectors with the Supra.You may have to move some pins around but im sure you can make it work..

Where are you gonna fit that GT45? I am sure you are talking about the Ebay one...It will feel like a dog on that 4L lol .

Any 67-71MM turbo will get you there, No need for a GT45.

 

Staying Auto

 

It's 69mm turbo in a kit I saw. Are the profiles the same between the Supra & 1UZ

 

Ok so its some ebay Turbo because the real GT45 is not a 69mm lol.

Please buy a decent Turbo, BW is already cheap that everyone should be able to afford them.

What profiles are you talking about? Im not sure what you are asking .

 

I am very unfamiliar with the 400 platform but I'm fairly confident it has the exact same transmission as the 300 and that stock auto will live a very short violent life at your stated power goals. May need to consider swapping to a TT auto trans, probably built (titan, BL, ATF) to be safe.

 

The problem is not not the trans but the ecu controlling it..it will dying because its not being controlled properly not because it's weak..its an aem thing.

Same way Honda hasn't figure out how to build a decent auto trans , same way aem hasn't figured out a way to keep the auto trans happy..

Not many ecus out there that will properly control the Toyota auto transmission..

 

its not great or perfect but you can make it work, at least the stock trans on the lexus has a line to the throttle body for line pressure, so on those transmissions its not even handled by the ecu. on a 2jzgte automatic, that is handled by the ecu.

basically if you set the shift points conservative it should hold up to a little boost, but just manual swap it there are like a half dozen manual swap options now for the sc400.

if you care that much about the trans you can go the piggyback route, but when I read a turbo sc400 build I think more for the motor/ecu combo that will put down power consistently, I would not choose those based on keeping the weakest part of the car which is the stock auto transmission. you might as well not even add the power to the 1uz then if you are going to stay with the power the stock trans can handle at that point a 1jz swap would be less work and much more fun and you will have more power out of the box with a gte trans that can handle it.

 

Manual is not an option for me

I planned on having my Auto built since I already have it.

 

Maybe you should consider changing that plan. People with experience are giving you sound advice and it sounds like you don't want to budge. Not to sound like a ****, but your parts list sounds pretty cookie cutter/half-assed for building a custom turbo setup for an engine that not many choose to boost. Some used rx-7 injectors? Come on man. Are you building a custom turbo manifold for a single configuration? Or a twin setup? These are things you need to think about. Otherwise your going to end up with a 3700 paperweight with a bunch of parts you can't use.

 

Injectors are new
Yes custom single turbo using both stock manifolds

 

how did you correlate target power number to target boost level? It doesn't work like that. Also, if you're not the one with the fab skills, the dollar amount involved to meet your goals with this project will double that of a 1jz swap which you can get running without really fabricating much of anything, a monkey can pretty much bolt together a Jz swap in a driveway. Either way, the cost of reliable 500whp is steep and if you're already looking at eBay parts that means you can't really afford it. That statement isn't made trying to be an *******, it's made because it's true. Go that route if you want, just know from doing this kind of stuff over the last few years with two 400whp daily cars in the stable for those said few years that cheating out leads to more money in the long run.

Another thing I guarantee you didn't think about is diff/subframe bushings, diff condition (bet it has a leak somewhere), and front suspension condition (bushings/balljoints/rack bushings). Most likely that stuff is shot or close to it. And stock struts. 400whp on high mileage 25 year old suspension is sketchy and dangerous, especially for someone that isn't seasoned to driving a vehicle with that much power.

Oh, and then there's your open diff. So you're basically gonna roast one tire at all times and get beat by stuff that has half the power and can hook. have $1200 for an lsd in that budget? You want reliable, better come with $7k minimum with you doing every bit of the work. Or spend like $3500 and start looking for a daily driver if you don't already have one that isn't the lexus in question here