Approaching first start on rebuilt 2UZ with Link ECU

The 1UZFE EGR Delete Kit is available for sale here.


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I've finally got my 4Runner motor back after dropping a valve on my rebuilt 2UZ. I did go with the heavier Kelford springs for the 208-B cams at Kelford's recommendation. I also added 650cc injectors and higher capacity fuel pump. I also added a Link G4X ecu and wired it in piggybacked with the stock ecu. This is a N/A motor, 10.5:1 compression, with forged rods and pistons.

I'm just about ready to start the motor for the first time, and trying to work out some logistics and options. It was really hard to find a tuner in California for 2UZs and aftermarket ecu, particularly for a 4x4. I finally found someone in Orange County--300 miles away. So I need to trailer the truck down for tuning, and that's where things get complicated.

My plan is to do the initial start, and possibly the first 50-mile run in, here at home, and then trailer the truck down for tuning. Based on watching a bunch of Gloverman's videos and some Link videos, it seems like I should be able to do the first 20-minute run-in in my driveway with a base ecu map, just updating the map for my injectors. Is that right?

What I'm less certain about is getting it on the road for that first 50-mile run in. Will a base map without tune be good/safe enough for a typical flat road run in for 50 miles? If so, should I put more miles on it after the first 50 miles before sending it to the tuner? Or should I be doing less before sending it to the tuner?

One other area of questions for those in the know about Link ecus. Should I be adding/replacing any stock sensors for tuning an N/A engine? I've seen discussions about adding a Link MAF sensor, AIT and Lambda sensors. Is that more relevant for boost situations, or still important for an N/A build?

Thanks for your input.
These are some of the checks I go through when firing a new engine.
Assuming the engine has been assembled and lubricated well (bearings, bores, cams etc) during the rebuild.
Some prestart checks to do:-
Double checked Cam timing is correct.
Shim clearances correct
All sensors connected and wiring correct, ECU powers and you can connect to it
Load map and make any adjustment required for prestart.
Fill with lubricant, best to use a Non deterent oil for bed in. Fill and check for leaks. Do again after start and running
Filled with coolant, check for coolant leaks. Do again after start and running
I like to crank the engine over without plugs for a few seconds to make sure all looks and sound ok. Can even do a compression check for piece of mind and baseline for later. You can even see if you can riase oil pressure.
If the engine starts, the the first things is to ensure you hold oil pressure and the next 20 mins of run time is used to break in the hardening on your new cams, so follow the kelford instructions.
Check engine temp, coolant and oil leaks while the engine is running for the cam break in.
Check ignition timing at some point before you take it out on the road.
Bedding the rings in is done by varying engine speed and engine load however you need to be weary that the engine hasn't been tuned so only use light load and low RPM. Do not over heat.
Hope all goes well.
Good luck
Really helpful--thank you! One remaining question--I'm replacing the stock injectors. Would you recommend running the stock injectors for that initial pre-tune run-in, or not worry about it? Thanks!
I'm happy to offer my opinion.... Given you have fitted an after market ecu and camshafts, I would probably opt for the stock injectors to get it running and do some quiet road run in miles prior to a dyno tune. Most startup maps offered by ECU suppliers are for standard engines. If you feel confident in remapping for the larger injectors, then go for it. Keep in mind you may also need to tweak idle control with modified cams. Your tuner should guide you on all that.
What or whos base map are you using? As the link "base" maps have a preferred name of "startup" maps. They are designed to allow a quicker setup with a known startup setting. They are not designed to be driven on. Especially with modified cams.

Do you have wideband sensors and fuel pressure sensors?
What or whos base map are you using? As the link "base" maps have a preferred name of "startup" maps. They are designed to allow a quicker setup with a known startup setting. They are not designed to be driven on. Especially with modified cams.

Do you have wideband sensors and fuel pressure sensors?
Hello! Help me Obi-wan, you're my only hope! :)

Here's the current status. I'm still getting a couple of sensors to add in, and haven't gotten to first start (though I've watched a couple of your videos on things like priming the oil pump...)

I am indeed adding wideband sensors. I did not have a fuel pressure sensor on the shopping list but can add it. I was told to leave the MAF sensor in place as one of the leads apparently communicates with the transmission (?), and that a MAP sensor wasn't necessary for a non-boosted motor.

I do not yet have a startup map--I'm still trying to get the lay of the land, particularly trying to understand the challenges with the automatic transmission. I have the Link ECU piggy-backed on the original, but while the wiring harness provider (XAT Racing) assures there shouldn't be a challenge, none of the tuners I've been talking in California seem to know about tuning the 2UZ with an automatic. I'm getting questions whether there's anyway to tell what gear it's in, for example.
This video might help.

This is a similar setup with a 1uz vvti with a link storm and stock auto.

When I supply a loom I supply a startup map with the wiring, and I've done lots of vehicles which an aftermarket ecu and stock ecu as the TCU. Most of mine are also tested on a running engine before sending them out so I know it all runs as it should although its not practical to drive the auto side of things. And then I support the purchaser throughout the installation. There are lots of tricks in the video like I always use a MAP sensor for the engine management although I don't think I show the tricks to deleting the stock MAF in those ones as I think I was in the testing stages at that point but these days I use the aftermarket ecu to generate the primary airflow load signal for the stock TCU which allows some forms of tuning. But this is just how I do it, other guys may get good results doing things differently.

Given the info you have supplied I'm not willing to assist further with remote tuning or startup map creation as it's done differently to how I would do it. Good luck finding a suitable tuner. Cheers
Thank you for the follow up. I'm regrouping this week to figure out how far off I am from your model. I'll circle back when I have a few more answers. Thank you!