Easiest way to make ST165 tunable

M

Mateo

Member

• Sep 1, 2020

• #1

I want to be able to tune my ST165 because it has quite a few modifications at this point, what will be needed to make it tunable? I've seen some of those systems for 4AGE's that plug into the factory ECU and allow you to tune with a connecting system.

 

M

mickeyfinn

Member

• Sep 2, 2020

• #2

Go with a Link G4X plug-in ECU.

https://dealers.linkecu.com/TST185X

These plug right into factory ST185 / MR2 wire harness.

But since you have an ST165, you’ll need an adapter harness.
Kris at KO Racing just came out with a nice one here:
http://www.koracing.net/viewproduct.php?folder=197&product=1531

Or you could use this one:
https://www.tweakdperformance.com/product/3sgte-st165-harness-to-st185-or-st205-ecu-jumper-harness/

 

M

mickeyfinn

Member

• Sep 2, 2020

• #3

If you do go with Link, you could buy it from ATS racing:
http://atsracing.net/Parts/Details/EL-VIPEC-PNP

That way you’ll get a base map to get you started.

Looks like the KO Racing option also includes a base map too. That’s probably the cleanest and best option.

 

M

Mateo

Member

• Sep 2, 2020

• #4

Are the ECU ports different from 165s to 185s? I'm pretty sure I've seen that you need an adapter to go from different ECUs

 

M

mickeyfinn

Member

• Sep 2, 2020

• #5

Yes, they are different. The adapters I posted are what you need.
You need to change from ST165 ECU plug to ST185 (early ‘90-‘91) ECU plug.

 

M

Mateo

Member

• Sep 2, 2020

• #6

They are a bit pricey but the 2nd adapter you posted was the one I saw before, thanks for the links though. I'll definitely look through them.

 

A

Alikazam

Member

• Apr 15, 2021

• #7

The KO Racing one is a direct plug into the ST165 connectors. No need to change harness. Fyi. Goes inside a factory ecu case. So mounting looks stock.