Molotovman

iTrader: (49)

Buy a standalone, ditch the stock turbo. It's a waste of time.

Aaron Cake

iTrader: (1)

I've picked a few posts out of this thread to reply to. Much of it has been covered already, however I'm concerned the OP is heading towards a disaster.

Cool. You've done the easiest part.

Maybe, but you are still at a loss of time (that has a value) and money for the parts required to complete the project. Plus, which you may not be aware of, an engine blown under boost can eject bits of apex seal directly into the turbine, trashing the turbo. You've also trashed what may have been a perfectly good set of rotors, housings, and possibly irons.

Stop. Right. There.

There is no such thing as a "chip" for an FC, unless you are referring to the RTek, which is a modification to the stock ECU to make it tunable. It's a good part for basic upgrading, but is limited on the size of injectors it can use. From memory the RTek really only natively supports 720CC secondaries. This is a limitation of how far the stock ECU can be pushed. Great for stock turbo applications. So go with the RTek, a set of 720CC injectors, and the stock turbo (upgraded fuel pump, accessories, etc. etc.).

No. Especially on the stock ECU. Even on the turbo ECU I have major reservations of running around that much boost. You can throw as much fuel as you want at it, but the real issue is timing. The NA ECU (which I assume you are referring to here because of the 6 port turbo) runs aggressive timing and you'll be around 30 degrees advance at WOT high RPM in boost. WAY too much timing for a turbo engine, high compression or not. Even the TII ECU will be running timing in the high 20s. OK for stock boost, way too much timing to remain reliable at 12 PSI, and an absurd about of timing on a high compression engine.

If you intend to go with the stock turbo, then use the RTek. It will allow you to drop timing to safe levels and more precisely control fuel.

The stock rad is actually pretty good, so if it's working well then an upgrade isn't necessary. FMIC, yep.

Ain't gonna happen on the stock turbo. ~250 HP (wheel) is about average. ~270 HP (wheel) with the turbo reasonably maxed out a port job and a good tune. A bit higher with a high compression engine. Just about 300HP is where I draw the line and say a standalone is absolutely necessary because you'll need more timing control than the stock ECU can provide. Plus you will run into issues on the stock ECU with a lean spot at injector transition, exactly where detonation is going to happen. Additionally, start extending the stock ECU with piggybacks, higher fuel pressure and larger injectors, and the car starts to become more finicky.

So, since you are using the stock turbo, you aren't going to see 300HP and you can get away with the RTek.

If you want to make 300HP with less boost, it means running a larger turbo, and thus of course a standalone. Injector sizing is not dependant on boost, but power level. If you want 300HP, you need injectors large enough to support 300HP (4 x 720CC).

The beauty is, what you think is irrelevant. What is required is relevant.

Nope, not even close. Both the S5 and S4 turbos have about the same power limits. The compressor map can be found by a little searching, which tells you how much air the turbo flows at various RPMs and at what efficiency. This is how you can determine how much power the turbo will probably make. The limits of the stock turbos are well known.


Those results are questionable, to say the least. ITO is a respectable and well experienced guy, but anyone can be mislead by flaws in their instrumentation. We cann'ot change the laws of physics, cap'tain!

None exist.

Uh, no.

For starters, the port timing on the 6 port block is not even remotely close to the 4 port. A 6 port block is (roughly...please excuse me here) like a 4 port block with a massive extend port. Plus there's that slight issue of high compression rotors.

Again, what you think is great, but reality has something else in mind.

At this point, STOP.

There are two things you must read.

"Street Turbocharging"

"Street Rotary"

Understanding how engine compression effects things like boost is vital. You start packing air into a high compression engine and you are radically increasing the amount of heat generated. Fire the spark too soon, or have too lean a mixture, and you get detonation. You must drop timing considerably to have a reliable high compression turbo rotary. I usually recommend about 15 degrees total advance at 10 PSI, then be dropping timing to hit 10 degrees by 15 PSI. That's half of the stock ECU!

Etzim

Thanks everyone for your replys, i understand where this is getting at.
The main thing i was worried about with what i wanted to do was leaning it out or detonation.
When i meant chip i meant an ecu modification like "rtek" I do not have a n/a ecu available at all. My engine use to be s4 turbo swap with s5 turbo, before it cracked two irons and had a stuck side seal, it was pretty nasty to see. I bought it that way tho.

So from what I have been reading from "Aaron Cake" and others, I should be fine with a wideband, S-afc, Rtek 1.8, 720cc secondary injectors, walbro 255 fuel pump, fmic, and a good tune at 10 psi and if im lucky i might make 260hp. Guess i need to change my mind on my hp goals.
Looks like I will have to do some reading, thanks for the links provided Aaron.

Out of curiosity what is a good inexpensive stand alone, if they exist..?

driftxsequence

iTrader: (8)

Why not go with a megasquirt? MS2 from diyautotune plus a harness comes in at a total cost of less than an RTEK 2.1 not including the hassle of finding a palm to tune it with. I picked up my MS2 for 270$ a full standalone for a 1/4 of the cost of most big name ones...and it has all the features! a harness is $85,

fast87t2

iTrader: (1)

^+1 im headed down the same path right now. S4 6-port with all the turbo goodies bolted to it. All controlled by a MS2. Cant beat the price-- $486 for a diy kit ms2 kit, diy sim kit, 12' harness, sensors and the zeal daughter board. Half the price of a haltech and plenty of people are putting down good power using it
--joe

Etzim

I will look into it, i have heard about issues with megasquirt tho.

Lets just say i want to wait before i spend all this doe on these parts to get my 10psi of boost or w/e.
Can i just run the 6port turbo stock with my s4 turbo ecu?

Etzim

Just like to add, Is this the correct ecm to get? MegaSquirt-II Programmable EFI System PCB3.0 - Kit w/ BLACK CASE DIYAutoTune.com It looks as if the ecu is not even assembled and i would have to solder all the resistors and everything else on the main board? is that worth it and something easy to do? because for this price im considering standalone lolol, funny how i said i would never

fast87t2

iTrader: (1)

You could run it with the t2 harness/ecu and appropriate sensors. I was planning on just running a lc-1 and a safc for my na/t2. But the fact that even a used safc 2 goes for 200+ on ebay and will only support stock boost levels on a 6-port turbo. Why not spend the little extra to support any other crazy ideas that come along. Aaron has a excellent write up on his site about squirtin' a FC

http://www.aaroncake.net/RX-7/megasquirt/index.asp



--Joe

Aaron Cake

iTrader: (1)

Why buy the 1.7 and an S-AFC? The 2.0 allows fairly decent control over the entire fuel and ignition curve, some basic injector selection, staging settings, etc. Probably cost less than the 1.7 and an S-AFC.

S-AFCs are pretty old tech at this point. Nice for correcting the fuel curve on an NA with the stock ECU, not very helpful with a turbo. Note that as you pull fuel with the S-AFC by tricking the engine to think the AFM is reading less, the ECU advances timing.

The most inexpensive standalone is the Megasquirt. However it requires a bit more work than the others because it is a DIY ECU so in general, I don't recommend people go Megasquirt based on price alone. The entry level Haltechs are under $1000. Used ones could be a few hundred dollars.

You will find people complaining about every ECU, but with the Megasquirt I've noticed a trend. I've seen again and again that those who are so strongly opposed to the Megasquirt usually base that opinion on ignorance. For example, I read a thread from a few years ago on another forum where a very experienced member was shooting down the Megasquirt, but one of his main points was that he "didn't want to learn to write code". No one needs to write code to use a Megasquirt unless they intend to seriously hack the ECU, for example to add features. The others who bash the Megasquirt are those who have run head long into a project with a 'Squirt, not having enough knowledge/understanding to accomplish it.

Yes, on a basic level you can run the 6 port high compression block on the stock turbo and turbo ECU. As long as you keep the boost around stock, you will be basically fine.

That's an unassembled kit. You can also get them completely assembled:
MegaSquirt-II EMS System - SMD PCB3.57 w/ Black Case DIYAutoTune.com

Then you will need to add this to use the stock CAS:
Zeal Engineering Daughterboard with Dual VR Conditioners DIYAutoTune.com

Regardless you will need a wideband for tuning and closed loop AFR control.

Etzim

Thank you Aaron, i appreciate your and everyone elses responses. I have my mind completely changed on standalones, i also really like the idea now of a standalone. It makes pretty good sense to get one now, if i want to run more power out of my engine it would be a lot easier to tune and reliable to run on a standalone ecu.

I'm deciding to ditch the rtek and any other ecu mods. I briefly looked over "Aaron Cakes" guide for the megasquirt and it sounds and looks like something fun to do. It would also benifit my rx7.
I'm just a little curious on how long it would take to put that ecu together with some electrical knowledge? I'm no professional but i am a diesel mechanic in training, i already have 2 years of highschool training and im a freshman in college.

Also on a scale from 1-10 how hard is it to run an engine on the megasquirt for the first time? What are some good benefits?

Im ditching the s-afc idea and the rtek, so now i want to try and run 650cc primary and 1000cc secondary with a wideband and a megasquirt with a fmic and my turbo on 10-12psi. also what a fairly inexpensive turbo upgrade besides the bnr?

BTW, what on the engine that the stock ecu would normally run does the megasquirt not. Basically what will i not use in my engine bay with that standalone?

joeylyrech

iTrader: (11)

2 high of a compression ratio and not enough timing pulled blown engine!

joeylyrech

iTrader: (11)

Standalone!

driftxsequence

iTrader: (8)

Etzim. It took me around 9 hours to build, and that was really taking my time making sure I got a good amount of solder in each hole, double checking instructions to make sure I grabbed the correct part etc.

My car started without an issue on the megasquirt thanks to aaron cakes base maps. It really was as simple as loading all of the parameters and making sure the wiring is correct.

you may want to check out my build thread, I just completed my 6 port turbo with a megasquirt, it sounds like you are doing something similar. I spent roughly 2500 (biggest cost being $500 on injectors, $550 on the turbo rebuild, and $400 for all of the pieces for the megasquirt)

Etzim

I checked out your build thread. Looks like you spent a lot of time on that wiring, it looks really good.

The main thing im concerned about on my engine is, my port match is pretty deep in the intake instead of rounded.

When i bought my motor it said 143k on the odometer, but when i was dissembling it i found some writing in orange, and everything looked very clean, the main bolts looked fresh installed too, im thinking the engine i bought was rebuilt not to long ago or something. I sure hope so.

what would it cost to rebuild a 6port s4 engine with 2 piece apex seals? I might want to do that before i ruin the irons and housings.

Hypertek

iTrader: (3)

400hp is some really big numbers to push. Being realistic I would be happy with 300-320hp in my car. I was planing to go with S4 NA rotors in my turbo build if i get a block from my buddy to take apart. Hybrid turbo and run it around stock boost levels with tuning.

Check out the diypnp, seems interesting and the most affordable ecu I think. You got to build it of course.
DIYPNP - The Build It Yourself Plug and Play ECU! Megasquirt Kits / Assembled Engine Management Systems, Wideband o2 Sensor Systems and tuning products - DIYAutoTune.com

Etzim

340hp sounds nice, i never said anything about wanting 400hp tho.
I have my mind made up, im going to go with the megasquirt. Hopefully i dont have to many roadblocks with this project.

driftxsequence

iTrader: (8)

it's really not that bad. the wiring was easier than doing the actual modifying of turbo parts. I would highly recommend getting a turbo front plate put on! the hardest part for me was the oil drain. everything else is practically swapping parts (besides modifying the lower manifold)

Etzim

Wiring doesnt really intimidate me, it just looks like the amount of wiring would take a few days. Reason i took everything off my n/a motor is so i could put EVERYTHING turbo on it haha. Thats the idea so i dont have to figure out my turbo cooling. I just need to retorque my flywheel nut and get a gasket for the front cover and im good to go.

Aaron Cake

iTrader: (1)

A standalone is always the way to go after basic modifications, and even a totally stock car will benefit greatly from an updated EFI system and a proper tune. The other bonus is that with a good tune, you'll get much better fuel economy than the stock ECU will provide.

The way I see it, the money saved on building over buying is only valid if you don't value your time. Or, you want to use it as a learning experience. The nominal cost of going with the updated 3.57 SMD board vs. the older 3.0 solder it yourself board is minimal when you consider the 3.57 board is a more modern design (jumpers vs. jumper wires, built in pullup resistors for the LEDs, idle mod already in place, etc.). It takes about 7 - 10 hours to assemble the board in kit form, with plenty of testing at several steps. If you do go with the kit, you'll also need to purchase a Stim, which adds to the cost. A Stim isn't really necessary when buying pre-built. My writeup is also a bit out of date regarding the VR circuit. Nowadays with MS3 you don't need to build anything, and even with MS2/MS1 there is the Zeal card.

With the maps on my website, the car should start if the wiring and build is correct. But if you don't have any tuning experience, the learning curve will be steep.

BNR.

With the Megasquirt you are eliminating all the emissions solenoids and such. You can still run a cat if you wish, and nothing else has to be disabled.

texFCturboII

iTrader: (17)

Just out of curiosity, Aaron: what kind of fuel mileage would you estimate? Not contesting your statement here, it makes perfect sense, I'm just curious/attempting to justify getting another t2.

Etzim

1 reason I want to do the megasquirt is because I would assemble it, I would gain a good amount of pride out of that and I'd love to do it for the learning experience. Its well worth my time to save the money on something I can do for free.

What exactly will be necessary when assembling the ecu? Like things you didn't mention in your diy? Unless thats all still covered with the megasquirt2

I have some experience with diagnostic programs and a little tiny bit with tuning programs. I'm sure i can catch on with it after a while, if there is anything you recommend i look into about it lmk. Thanks