ClubLexus - Lexus Forum Discussion - 1992 SC300 NA-T Build List

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1992 SC300 NA-T Build List

Hey everyone, I’m new to the forum. I just bought a 92 SC300 to use as a project and ordered what I hope is everything I need for the NA-T swap. Unfortunately it’s automatic but it was $1200 so oh well. I’m not new to cars but this is my first turbo build so if anyone sees something I’m missing PLEASE tell me. All the parts should be here within the next few days and I’ll post more pictures and info as the build progresses. I’m on a budget (student) so I had to make some sacrifices in places. I’m hoping to make about 450 whp to keep the stock trans reliable. Do I need to buy a fuel pressure regulator?

-Used GT35R (ported and ceramic coated)
-Tial 40mm WG
-GTE HG
-ARP Studs
-Walbro 255
-650cc injectors
-Used Apexi SAFC
-10 an oil return, 4 an oil feed, 6 an water lines for turbo
-Ebay tubular manifold
-Ebay DP and dump tube
-CX Racing intercooler kit
-HKS BOV
-AEM wideband
-Boost gauge
-Fuel cut defender
-Hallman manual boost controller
-NGK 4644 plugs
-Will do a full fluid and filter flush
-I’m considering either building the automatic transmission or swapping in a TH400 when I have the money saved

Quote:

Originally Posted by IISevv (Post 10222363)

Hey everyone, I’m new to the forum. I just bought a 92 SC300 to use as a project and ordered what I hope is everything I need for the NA-T swap. Unfortunately it’s automatic but it was $1200 so oh well. I’m not new to cars but this is my first turbo build so if anyone sees something I’m missing PLEASE tell me. All the parts should be here within the next few days and I’ll post more pictures and info as the build progresses. I’m on a budget (student) so I had to make some sacrifices in places. I’m hoping to make about 450 whp to keep the stock trans reliable. Do I need to buy a fuel pressure regulator?

-Used GT35R (ported and ceramic coated)
-Tial 40mm WG
-GTE HG
-ARP Studs
-Walbro 255
-650cc injectors
-Used Apexi SAFC
-10 an oil return, 4 an oil feed, 6 an water lines for turbo
-Ebay tubular manifold
-Ebay DP and dump tube
-CX Racing intercooler kit
-HKS BOV
-AEM wideband
-Boost gauge
-Fuel cut defender
-Hallman manual boost controller
-NGK 6097 plugs
-Will do a full fluid and filter flush
-I’m considering either building the automatic transmission or swapping in a TH400 when I have the money saved

you need a computer.

At the very least use Alisc3's TT ecu guide and put a supra computer in it. If you can spend the money for aftermarket AEM, and tune that that's even better.

You won't be able to tune the stock ecu with a garbage piggy back like the Apexi SAFC. Your only going be disappointed and possibly damage the engine if you try to run boost on a stock Sc300 ecu.(if you wana run 3 or 4 psi you could use stock ecu but any more then 5 the car freaks out and has no idea what to do, not to mention if you let off and dump all the air from the system the car will die because your MAF won't be able to see the air leaving the system once its pasted through the MAF. You need MAP sensor to detect pressure and lack of. I tried running my stock ecu with boost on an auto trans so i'm only speaking from experience and i tried using an AEM FIC 8 as my tuner which is years ahead of the Apexi safc

Quote:

Originally Posted by scsexy (Post 10222472)

I thought the 2jzge already had a MAP sensor? What you’re saying makes sense but I’ve heard so many conflicting things. Some who have done an na-t swap have told me that a SAFC wasn’t the most efficient controller because you can only go rich or lean, but that it worked for them. I’ll have to look into it more. The reason I didn’t go stand-alone is that I would rather spend that ~$1000 elsewhere and I had other people telling me it wasn’t necessary.

Quote:

Originally Posted by kitabel (Post 10222511)

I don't think your stock A340E is safe at that power level, I've read 325 hp as safe, the Aristo/Supra special TT model is considerably stronger but the parts don't swap. More comments on my page here: http://www.victorylibrary.com/Toyota/A340E.htm. A strong TT transmission requires a TT core or $500 core charge, in addition to about $3,000 for the work.
TH400 is $$$$ and cutting the tunnel, cross-member, driveshaft, controls, converter.
Your ECM has no spark retard for boost, so your only compensation is very rich. The TT auto has its own retard on shift.

I was looking at the Titan Motorsports built A340E as an option. $2200 out the door.

Nevermind, you’re right, it’s a MAF. I have everything ordered and it’s not my only car, so I think I’ll try to run it with the MAF. I’ve been scouring forums and have seen other people who have successfully kept the stock MAF as high as 450whp. I’m a little confused about needing to get rid of the MAF because I come from bmw’s and everyone who boosts those ditches their MAP for a MAF.

For every person who’s done this or that reliably, someone else blew up their car doing it. It can’t hurt to install the setup and see how it runs. Too late to cancel it at this point.

Until I have a chance to get a new trans I will be shimming the accumulators And installing a cooler. Hopefully that’ll at least help it hold up.

The AEM wideband kit comes with its own screw/weld in type sensor. Given that the stock ecu has connections for 2 o2 sensors, do I splice them together and then splice the new sensor into that? I would think that would cause the ecu to freak out because it’s used to seeing 2 separate signals. I’ve seen people splice the wideband sensor into one of the existing sensors but they don’t explain what to do with the second, unused sensor

If people are interested and I can help others, I can create a step-by-step DIY with pictures.

There’s a guy local to me selling a newly rebuilt TH400 with torque converter for $500. I might be wrong, but other expenses (shifter, adapter plate, mounts, etc) only seem to be in the $700-$1000 range

I may be selling my aem v1 that has been ultra reliable since 2008 . I would leave alphas tune in there and all we would need to do is make adjustment in fuel injector scaling etc...this would be solid option as opposed to safc route as my car starts , runs like a stock sc as alpha is the master