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· 2JZ yes shit
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1,208 Posts
Discussion Starter · #1 ·
Let me start off by saying that my goals when going single were very simple. The quickest spool, lots of low-end torque, and a turn-key car that is "set it and forget it". I don't even have a single gauge in the dash. I want it to run and drive like stock. I shouldn't need to monitor AFR once the car is tuned and the setup hasn't changed.
With that said, my goal was almost fully realized, with the exception of proper boost control.

I ended up using the MAP ECU 2, an innovative wideband, and the MAP ECU-recommended GM solenoid for boost control.
This $75 GM solenoid came to be the bane of my existence.

On paper it looked fantastic. It was priced right, MAP ECU 2 controlled it, it had the ability to program a different boost pressure every 1000 RPM, and I could switch between high and low boost by using two toggleable maps with the flick of a switch.

My setup is very unique. I am using a GT35R with a T3 0.63 exhaust on a T4 cast manifold with a T3 adapter flange welded on. Basically everything I can do to promote quick spool.

Once the setup was put together, it went off to the dyno for tuning. I spent about 6 hours of dyno time just screwing with the piece of shit boost controller and it still would not hold boost properly. At full boost (3400rpm), it would want to overboost, and then the EBC would try to prevent overboost by over-compensating duty cycle and thus dropping the pressure down. I could barely do a few pulls that actually held 18psi, but I did manage a few.
Not much later, MAP ECU sent me a new version of their firmware that they said should fix this issue of the EBC being too compensation-happy.
I did some street tuning and it looked promising. But the problem still was that you had to keep adjusting and trying new gain and duty cycles; each of which required a WOT pull, and on the street it isn't very easy to do without risking some jail time and impoundment.
I thought we had actually got it to hold 18psi at one point, and then it threw another curveball my way by randomly spiking to 30+ psi. It was totally random. Nothing in the tune or settings would change. Literally one minute you go WOT and it holds 18psi to redline, and then the next minute you attempt the same thing again and it shoots to 30. What a cunt.

I decided I had enough with this and I read some posts from Mr. Ken Henderson regarding HKS as a whole, and some other threads of his talking about the superior technology in HKS boost controller stepper motors. I settled on the HKS EVC EZ, because I want to set it and forget it. I don't need multiple levels of boost. I want to set it once at 19 and tuck the boost controller into my glovebox and never look at it again.
This controller does just that. It has an ON/OFF switch and a dial. That's it. Turn the knob and boost goes up. The end.

After the horrible experience with this POS boost controller I expected HKS to outperform it, but not by this much! Wow, let me tell you....
The moment I installed this and did my first pull, the boost was fucking perfect. I mean literally perfect. Looking at the log, you could take a level tool and put it next to the screen and it will be the most rock solid straight line you will ever see. Unbelievable. It doesn't even need to learn. There is no internal memory, there is no 12v constant power source. This thing just knows how to hold boost.

Since installing it I even picked up more low-end torque because this unit keeps the wastegate shut tight until it needs to open.
For the money I spent on the dyno with this shitty GM solenoid, I could have bought 3 of these boost controllers and spent my dyno time actually perfecting the AFR and timing.

From now on I am a die-hard HKS fan. You really do get what you pay for, and now I understand why Ken uses HKS wherever possible. Absolutely top-notch above-OEM quailty.

For those of you who want to see what the car did on the dynapack at about 18psi with the old boost controller, please see here. Peak HP that day was 488whp on another run:


I also plotted my graph against a few popular cars so you can understand how amazing this GT35R setup is, and why it truly is a response machine:
 

· Super Moderator
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13,803 Posts
Dj,

Thanks for the kind words. Your experience with the HKS EZ replicates exactly the experience of my good buddy Lagtime when he went from BPU to APU and installed an HKS EZ boost controller at the same time. It truly is set and forget. I'm glad things worked out for you.

Ken. (HKS EVC-Pro in Blackie and HKS EVC VI in Eau Rouge)
 

· Banned
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Glad its working out for you.
Told ya its good unit.

Only reason I got rid of it after 5 years was to have AEM now control my boost settings.
 

· Registered
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2,998 Posts
A friend of mine is looking for a EBC for his stock twin auto Supra. He was considering the EVC EZ but I told him it might not work too good with the stock twins. Was I correct in telling him that??

If the EZ will not work, what is the EBC of choice for stock twins??
 

· Banned
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it will work fine from stock twins to big single
just 1 knob more boost or less boost.
 

· Registered
1994 Toyota Supra Turbo 6spd
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how does the HKS EVC ez 2 compare with the original EVC EZ??? of course ease of use i'm sure the original would be way easier (one knob). but as far as precision/consistency and range of boost levels, would the EZ 2 come out on top?

i used to have an HKS EVC4 on the supra... that thing was a bit hard to use/a lot of features to control... maybe i just didn't know how to use it..
 

· Old School
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4,443 Posts
Dj,

Thanks for the kind words. Your experience with the HKS EZ replicates exactly the experience of my good buddy Lagtime when he went from BPU to APU and installed an HKS EZ boost controller at the same time. It truly is set and forget. I'm glad things worked out for you.
I like simple and functional. HKS delivers.

how does the HKS EVC ez 2 compare with the original EVC EZ???
I have the EZ II. It is just as simple to use as the original EZ, the second knob controls a second preset boost. Having three different, preset boost levels rocks.

Mine is set to:

Off = wastegate
A = Pump
B = Race gas

The only downside to the EZ series is the lack of a variable duty cycle to the wastegate, so you can't adjust out the small boost drop as you approach redline. The EVC 6 has this feature, but it is not simple to adjust.

Chip
 

· Registered
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2,684 Posts
I had an EVC EZ stepper motor fail. It kind of felt like a slipping clutch. On full boost the rpms would go hi then low, and it would oscillate back and fourth like this.

It was a complete PITA isolating the failure.

The EZ II has a different stepper motor IIRC. That's what I went with for round two.
 

· vvti. what
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820 Posts
hi, im having trouble getting my evc ez II to work. ive read the directions plenty of times and still no luck. i turn the knob and try to do a boost run and boost doesnt change. the power button is not blinking so i figured there are no errors. could i have a bad stepper motor? vac lines are routed how the manual online says.

also i noticed that when i turn on the car and the evc automatically turns on it goes straight to vol B even tho i try to set up vol A and turn it off in vol A.

ive talked to supra owners at local meet and they recommended resetting the unit but they dont remember how. can anyone help me?

thanks
 

· MKIV Fanatic
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1,018 Posts
I just purchased my BPU+ supra a couple of weeks ago. It currently has mostly HKS parts installed, including HKS EVC boost controller. Although I've never met or really talked to Ken Henderson, I figured from all the mentioning of his name, etc... that he's quite a well known figure in the Supra world. I've been doing some research on boost controllers, and it seems like there are some disparities between opinions generally found on Supra Forums, and MKIV.com.

Here is a copy from a reply post by Ken:

Quote:
Originally Posted by Radride
I will never use a HKS based boost controller in my car ever again. I had one in my fd before I bought the Blitz. It was the HKS EVC or something like that. Needless to say it spiked to 20psi costing me my motor. $5000 later I went and bought a real boost controller; the Blitz SBC-ID, and never looked back. HKS can kiss my ass.

R.K.
Sounds like your boost controller wasn't installed properly. Anything is possible but, if anyone could discover that HKS boost controllers had inherent boost spike problems as your post implies, it would be me. Other than PM Supra, over the 14-years I have owned Blackie and the 2 1/2-years I've owned Eau Rouge, I'm pretty sure my hundreds of dyno runs, to say nothing of my many long highway pulls and bike racing activities, are more than anyone else in this thread.

Quote:
Originally Posted by VeilSide935
Honestly, the only reason why I was inquiring about the HKS EBC too was because I noticed Ken Henderson is running one and I know he wouldn't buy something he didn't trust.-Tim
Quote:
Originally Posted by Radride
As for Ken H, he has a full catalog of hks parts on his car. Thats prpbably why he has a HKS boost controller.

R.K.
Quote:
Originally Posted by SealSupra-6
I used the HKS EVC-5 for about a year. Great unit, easy to use, never spiked and always held boost. Plus with the HKS units you don't have to run that stupid boost line into car. I highly recommend the unit.
I have had HKS boost controllers in my two Supras almost from the very beginning of ownership of both my cars. I installed an EVC III way back in the day on Blackie and replaced it with the EVC-Pro, which is still in the car. I sold the EVC III to a good friend of mine back in 2001 and it's still going strong to this day. I removed the GReddy Profec B in my red car and replaced it with the HKS EVC VI.

I know boost controllers today have a LOT of non-boost control bells and whistles but, when it comes to controlling boost and reducing spool, I believe the HKS boost controllers to be the best and most reliable. This opinion comes from over 14-years of combined usage of various HKS boost controllers and other HKS electronics for the same amount of time. During that time, I've never had a failure of an HKS part.

The Blitz is an excellent unit, so one cannot go wrong there. I just believe the HKS stepper motor technology is the best I've used. HKS boost controllers are the boost controller of choice for my tuner and engine builder, SP Engineering. Unless tha great choice.

Ken.



Here is a copy from the "faq" guide, found in MKIV.com:

1. my tt is currently stock, but i want to improve its performance. what should i do?
glad to hear you're ready to "really" join the tt club! we have found that the tt responds very well to the following list of basic performance upgrade s (bpus). these upgrades are proven (by us naturally!!) to have a high degree of reproducibility from car to car if you install all of the following:
exhaust system (most of the major brand name exhausts are fine)
downpipe with or without high flow catalytic converter (rod millan, speedtek, random technology, stillen, uprd, powerhouse & spp)
ebc or mbc (electronic/manual boost controller), not boost controllers w/ fuzzy logic (e.g.. profec a and hks evc)
fuel cut defenser (greddy bcc - highly recommended by the mkiv.com members. read why hks fcd is the same as the ffcd (using the hks fcd or the ffcd is only recommended if you have the ttc mod and 12v mod)
with the bpu installed, you can expect to obtain approximately 370-410 rear wheel horsepower (rwhp). damn, you gotta love the supra tt!!

you will also want to install a boost gauge to monitor how much boost you are running. obviously running more boost is going to decrease the life of your turbos (by how much is not really known) so you will want to watch this. a few turbos don't last long at all at higher than stock boost levels, but most seem to take the increased boost just fine. most people think the best trade off is no more than 18 psi although some have had success and longevity with higher boost. a conservative number would be to run 15 psi low boost with occasional runs to 17 psi if you get an ebc that is easily adjustable on the fly. even with a supra, you gotta be willing to pay to play...
back to start


Why does MKIV recommend EBC's or MBC's that are "non fuzzy-logic", such as the HKS EVC? I would really like to find out why these two major sites seem to have contradicting ideas on this product.

Thank you,
Jung
 
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