Some rambling, questions and need advice. Considering an EMS.

[kc95sc400]

Hey guys, need some input. Warning: LONG READ….LOL.

First, for anyone not familiar with my setup:

95 Lexus SC400. Stock motor, original as far as I know. Haven't even had a valve cover off. Supercharged with a Vortech V-9 running about 12psi. MaftPro piggyback, NO MAF sensor, GM 3bar. 315 injectors. Water/Meth injection. Built transmission. Dragon convertor. Prothane bushings. Bell FMU. 4.27 rear end gears with Torsen LSD. Suprastick. EKT/IMF headers. Magnaflow x pipe and rear mufflers. Lots of other little odds and ends.

I have been very successful running with this setup. I have put I think about 60,000 miles on it (currently at 166,000ish miles) and have made 200-300 (lost count) 1/8 and ¼ mile track runs. Have been as low as 7.702 in the 1/8 and 12.047 in the ¼.

Haven’t really had anything but minor issues here and there.

Until, a month or so back I went to the dragstrip. Did what I normally do. Let the car cool down for about an hour before making the 1st run. Did a burnout and staged like normal. Took off at the line and right about the time I was hitting 6000rpm in first I lost all power.

I went back today and did not have any issues. Made three passes, 8.024, 8.027 and 8.031. Not my best but at least it ran and didn’t have any issues. Since I had the problem I have messed with a few things. I found that the pressure relief valve on my Walboro pump had failed and was ALWAYS dumping fuel. I plugged it with a screw. I adjusted my fuel pressure lower, it was too high and I thought maybe I was jamming the injectors. Tops out at about 80-85psi now. I put a new timing belt on (was about due anyway) and re-did some wiring in the engine bay. I found that one of my front o2 sensors was dead (always reading 0 volts) so I have unplugged all of them. I am currently running without any 02 sensors, using the MaftPro to control what would be “closed loop” fueling. Actually works pretty good.

So, maybe something I did fixed a problem, not sure. But, I can’t help thinking that I was hitting fuel cut due to maxing out the MAF signal to the ECU. I assume this is possible with the Lexus ECU since it is a known problem with the MK3 Supra ECU’s and the smaller KV MAFS that they use. In their case, they upgrade the injectors and use the Lexus MAF. Well, I obviously can’t do the same combo.

I have honestly been thinking about making the move to a stand alone for awhile now. Something that’s always been on my mind and something that I probably should have anyway. It wouldn’t surprise me at all if I have indeed exceeded the capacity of the stock ECU. I have had quite a few people tell me that I am pushing it. LOL.

But let’s assume that the stock ECU did not cause my power loss problem, I’d like some input on why I should upgrade to a stand alone anyhow. I already have fuel control although I will admit it can be a little inconsistent. It was even before the FPR for those who might say that it is the problem with consistency. I guess the biggest question would be: Would it do me any good to have control over the timing. Seems that most of the time, the point of having control of timing is to retard it to a safer level than the stock ECU would. But, since I’m running the stock ECU with the stock timing (in power mode even) and have been doing this for quite awhile with lots of abuse and I have not yet blown up the motor, is there any point for me to have control over it? Now, this is assuming that I am not knocking enough for the stock ECU to use its knock control strategy which I’m pretty sure is full retard. I suppose that’s what could have happened at the track when I had the power loss but I don’t think so. I had no fuel, my AFR gauge was pegged lean.

If I were to go standalone, what would you all suggest? How much standalone would I really need? My setup is pretty simple. It would be nice if it could control the water / meth but not really needed. I’m pretty sure that any decent system could control anythine / everything else I have going on.

Ok, that’s enough for now, sorry for such a long post. LOL. I will be happy to hear any and all GOOD suggestions.

Thanks,

KC

 

[spf_lexus]

I am running a very similar setup to yours: proharger at 8psi, rush headers, managflow x pipe and 2.25" magnaflow mufflers and 4.27 final drive. I will be wiring mine into a 92' sc400 in about 3 weeks. I would reccomnd the adaptronic e420c for a good, affordable standalone. Its about 990 AU, but it has adaptive mode which constantly re-tunes the engine's fuel and ignition maps, automatically. I dont know of any other ECU manufacturer that offers this feature. My second reccomendation would be Megasquirt for its features and cost.


I am swapping a lot of parts from my LS project to feed this sc400 project. I have admired your setup and the respectible numbers your laying down and hope I can crack into high 12's someday. My sc is very fun in N/A form at sea level but when I drive it up to colorado all the "fun" disappears lol..

 

[cribbj]

KC, going to a standalone is a big jump and your success with it will depend on how good your tuner is.

If your car is a daily driver, and you need to jump in it every day, and have it start, run, and drive without any issues, that's one thing you'll not have with a standalone. There are always "some" issues with the consistency of the driveability with standalones.

If the car isn't your daily driver, and you can bear a few quirks with it as the weather changes, etc., and don't mind fiddling with the tune, AND you want total control over the engine, and the responsibility that goes with it, then maybe you're a candidate for a standalone.

The AEM is a great standalone which has been proven to be a plug in replacement for the stock ECU in the Supras and it can run everything that the OEM ECU does. It also has a "learning" mode like the Adaptronic, but in my experience, I don't think it works that well, and I don't know anyone that uses it. The Supra model of this ECU can plug right into the SC400 harness, and with a few minor mods, can run the SC400 just fine.

We're very fortunate to have Mitch Pederson here as a Lextreme member and SC400 owner. Mitch was a former AEM development and support engineer, and has run his SC400 first on the Generation 1 AEM, and now on the Generation 2. There aren't many people at AEM or elsewhere who know this ECU as well as Mitch does.

 

[XR8tt]

I have no issues with stand alone ECU's.. Its the tuner who's too lazy to do cold start etc...OR NOT competent with particular ECU...
As with all these tuning etc..
Talk to any local tuner that your happy with and go by his recommendations..
It can be wired up as they say piggy back which means the new ECU only tunes the engine.. Then leave std ECU to control idle, cold start etc..
Tmk in most cases you'll have to convert to wasted spark or direct fire if ECU doesn't have enough ignition drivers.. In most cases wasted spark or latter CDI 4 channel if ignition isn't up to power level?
EMS 8860 http://www.enginemanagement.com.au/cms/
and Haltech 2000 These come with plug and play for 2JGTE so plugs MAY work on 1UZ ?? http://www.haltech.com/?option=com_content&view=article&id=53&Itemid=49
work well for me..
Where you live I guess http://force-efi.com/bigstuff.htm
, or http://www.aempower.com/
or http://bigstuff3.com/

I would say the worlds best is still Motec.. They are pricey but the M400
is priced o/k these days.. Nothing special BUT does the job..Simple & efficient...
http://www.motec.com.au/aboutecu/ecucomparison

 

[kc95sc400]

Thanks for the input guys.

spf - definately let me know how it goes with the Adaptronic. I have always been interested in the unit and it seems that with the amount of 1uz use it gets it should be pretty easy to at very least get a good base map. Do you plan on tuning it yourself? Tuner support has been probably the biggest con in the use of the Adaptronic. I think this is why ScottURnot decided to sell his and go with AEM.

As far as the possible cons of changing to a standalone - Although my car starts fine I do always feel like I'm chasing my tune anyway and it has a few quirks as well. Mostly part throttle and tip in situations. I've always thought that a standalone would help this. I've always also thought that the biggest improvement would be in mid-range driveability. It is not as bad without the 02s and running in constant open loop but it always feels like the car (ECU) only has two settings, normal driving and power. If I ease into the throttle while holding any gear, it almost feels like once a certain throttle position and / or RPM is reached, a swith goes off and the car is all of a sudden a beast. If that makes any sense. I've always assumed that this was the transition between closed and open loop.

Should also note that I don't have a ton of money to dispose of. If I were to go standalone I'd probably try and stay within the price range of the Adaptronic e420c or the Autotronic SM2 or a few other ECUs with a similar price point. Should also note that I already have standalone transmission control so that is not an issue. Although I do think that AEM would possibly be the best unit for tuner support I don't think I can afford it.

I will have to do some research and talk to a couple of shops. There are actually a few around my area. I am also going to email Adaptronic to see what advice they can give me.

Regardless, I will be waiting for a check from uncle sam before I can do anything...lol.

Thanks and keep the advice coming!

KC

 

[cribbj]

KC, there are always some AEM's F/S on SF and eBay. Just watch and wait for the right deal to come along if you decide that's what you want.

An email to Mitch might be a good idea too. He may know of AEM's for sale. If you need his email addy, PM me.

 

[kc95sc400]

KC, there are always some AEM's F/S on SF and eBay. Just watch and wait for the right deal to come along if you decide that's what you want.

An email to Mitch might be a good idea too. He may know of AEM's for sale. If you need his email addy, PM me.

It's funny you mentioned that. Right after I posted I went to SF and checked. Found three after a quick search for pretty cheap.

KC

 

[spf_lexus]

Yep, I am planning on wiring and tuning my adaptronic myself. I just finished installing a megasquirt into a supercharged vw Corrado last week. It fired right up and this was my 1st standalone install so im feeling confident about tackling this. I had a supposed "tuner" try and install the 420c in my LS400 but it never worked out due to tuner incompetence as well as unreliable wiring diagrams. Wiring it into an sc400/soarer is cake, and Neil @ RushImports can make you a pre made loom that is true plug and play so it should be a straightforward install. The tech support at adaptronic isnt too bad. I get answers the same day and in great detail. Talk with Andy @ Adaptronic, he knows his stuff.


Also, David has reliable wiring diagrams for the sc400 as well as a nicely organized wiring guisde specifically for the e420c. I believe forum member Cobber put the tutorial together and I am planning on following his directions.

 

[kc95sc400]

So at this point I think I'm gonna get myself and Adaptronic e420c. Scott, if you read this I am now kicking myself for not buying yours. LOL.

I've been talking with Rob Knox from Adaptronic, Neil from Rush Imports and been browsing other forums of people who use it and it sounds good. I have also downloaded the tuning software and the users manual, everything looks simple enough. I am confident that it will do everything I need it to do. Although, it will not control the transmission FYI, but I have a Suprastick so I don't need it to.

Here's a link for anyone who hasn't heard about Adaptronic - http://adaptronic.com.au/

And here is where I'll likely purchase it from, was refered here by Rob Knox of Adaptronic - http://www.boundaryengineering.com/drupal/node/14

KC
__________________

 

[Cobber]

I love my Adaptronic and it controls my engine very well including the water meth injection. Great value for money.
The above mentioned tutorial is a bit old now but will still work fine, VE tuning feature will get a base map much faster now, the adaptive air fuel ratio part remains the same as the tutorial.

 

[kc95sc400]

I love my Adaptronic and it controls my engine very well including the water meth injection. Great value for money.
The above mentioned tutorial is a bit old now but will still work fine, VE tuning feature will get a base map much faster now, the adaptive air fuel ratio part remains the same as the tutorial.

Thanks for the input, that's what I like to hear. One reason for going with the Adaptronic is because of it's known usage on the 1uz. I know there's a few here and I think quite a few more guys on soarercentral that are using it.

Rob Knox @ Adaptronic also assured me that a base map could be supplied and fine tuning it would be easy enough for any tuner if not myself. I actually know of one guy over at soarercentral that has a very similar setup to mine who might let me have his settings to start with.

Heads up Cobber, I might have a few questions on your method of water meth control later since I also have water meth.

KC

 

[kc95sc400]

Ok, just made payment on an Adaptronic e420c with 18inch harness and decided to get a new 3bar sensor with it.

Hell of a deal I'm pretty sure, $761.91 shipped!

KC

 

[Cobber]

That's cheap, good deal.
Just send me a pm if you need any info.
Buy a wide band sensor if you want to tune it yourself.

 

[kc95sc400]

Thanks man. I will probably have a ton of questions, LOL. I think I'm going to start a new thread in the tuning section.

KC

 

[spf_lexus]

I have started labeling my wires buy nothing soldered yet. I am planning to pick up a second stock harness just for insurance. Since your SC is your daily driver, having 2 looms allows you to swap back to OEM without having to leave the car idle.

 

[kc95sc400]

I have started labeling my wires buy nothing soldered yet. I am planning to pick up a second stock harness just for insurance. Since your SC is your daily driver, having 2 looms allows you to swap back to OEM without having to leave the car idle.

I'll get it working one way or the other. Hell, swapping the harness would be a project in itself.

I was thinking about buying a used ECU to steal the connector out of and attempting to make my own PnP harness. Doesn't seem like it should be that hard to do.

KC

 

[cribbj]

I'll get it working one way or the other. Hell, swapping the harness would be a project in itself.

I was thinking about buying a used ECU to steal the connector out of and attempting to make my own PnP harness. Doesn't seem like it should be that hard to do.

KC

KC, talk to Richard Welch at Autosport Wiring. He'll build you a quality harness with fly leads on it in whatever configuration you want and won't pull your teeth out pricewise. He has access to all the the Toyota ECU connectors and builds "Fields Harnesses" for most of the major suppliers (MVPMotorsport, Titan, HPF, etc.) Great guy to deal with. Here's his email: [email protected], and website: www.autosportwiring.com. Richard's day job is doing avionics and wiring for one of the large commercial airlines, so he knows a thing or two about building a quality harness.

 

[kc95sc400]

KC, talk to Richard Welch at Autosport Wiring. He'll build you a quality harness with fly leads on it in whatever configuration you want and won't pull your teeth out pricewise. He has access to all the the Toyota ECU connectors and builds "Fields Harnesses" for most of the major suppliers (MVPMotorsport, Titan, HPF, etc.) Great guy to deal with. Here's his email: [email protected], and website: www.autosportwiring.com. Richard's day job is doing avionics and wiring for one of the large commercial airlines, so he knows a thing or two about building a quality harness.

Now that is pretty killer. I will contact him.

KC

 

[scotturnot]

Dang KC, Wish I still would have had mine to sell, it was all pre-wired. Hind sight 20/20 LOL
Hope this works out for you.