hey guys,

would a hks VPC and AFC2 work as a piggy back for the 1uz-fe? i was thinking about swapping in the R154 manual transmission into my 98 sc400.

i was possibly going to turbo it as well and was curious how much boost i can push safely?

thanks
jason

 

SAFC-2 will work on anything with a MAF. So yeah it'll work. But they're not that great and obd-2 computers have a way of not letting you piggyback.

The 1uz rods suck and are on the ragged edge at 500hp with an good tune. Especially the 96+ motors with the skinny rods.

The early engines are 10:1 compression and in 96 it goes up to 10.4:1. So it's probably only good for around 5-6 psi on stock injectors, 10psi max.

I've never turboed a 1uz, I'm no expert, there are others here that have, but I doubt they'll answer your question...you're only the eleventeen millionth person to ask the exact same question.

Does your car have the 5 speed automatic or did that start in 99 or 2000?

 

If you are thinking of swapping an R154 into your SC400, you will not need any piggybacking for the computer. I am running an R154 on my SC400 with the stock ECU. I am just throwing a few codes from the absence of the transmission.

An AFC2 will work with the SC400. By trimming fuel appropriately on the top end, you can increase power by preventing the richness of the stock fuel map from taking effect.

I am not sure if an HKS VPC has been used to convert to a speed density set up, but I am certain that speed density can be done on an SC400.

KC95SC400 is running speed density on his supercharged SC400 (at something like 10-12psi). He is using a MAFT Pro to manage his fuel. The MAFT Pro has a nice Air-Fuel Ratio feature where you can program in an upper and lower limit to the AFR range you would prefer, and the computer will actively alter fuel delivery, when necessary, to stay in that range.

The poster above is correct that the 96+ 1UZ motors have thinner rods. These rods are also in the GS400's that are pushing 350+whp through Vortech superchargers with the RMM kit that was out a few years back.

How much boost can you safely push? It depends on the size of the turbo. But, given the thermal efficiency of a turbo compared to a supercharger and considering the supercharger set ups that are out there, I would stay under 12psi. In general, I would try and keep the whp around 400. Anything beyond that, and you are risking reliability at the expense of cutting the corner of not going inside the motor.

Worth considering: a turbo project on a 1UZ is relatively uncharted territory. Either being skilled as a fabricator or knowing someone who is would be essential to getting the job done as there are no "kits" to speak of at the moment (to my knowledge). Supercharging, though still relatively uncharted, is a path that has been chosen enough to have some basis for your decision-making. Given the niche aftermarket that is present for supercharging the 1UZ, you can boost a 1UZ via a blower without extensive fabrication skills.

 

blizzy- on the sc400 (1uz-fe) say i turbo charged it and was planning on staying within the 550-600whp and i got upgraded injectors...

for the VPC, what chip do you think i need to go with?

 

if this thread is about boosting or a manual conversion for the 1998+ sc400, I'm subscribed!!!