Supercharger install

[mnewell]

Interesting information.

I don't know if this is related to your problems or not but I had a similar problem in my supercharged MR2 when I raised the boost from the stock 8lbs to 14lbs (done through a larger crank pulley). The problem was that below 3,500 RPM, when you went more than 60% throttle, the engine would get dangerously lean. The reason for this is because the engine computer goes nuts when getting the readings of A/F ratio and does not dump enough fuel into the cylinders to compensate for the additional boost of the SC.

There have been numerous ways of going about fixing this in the MR2 community. There was talk of different injectors and FPRs but these fixes were proven not to work because the stock ECU doesn't make up for the additional flow. The only options at the time were a switch to a MAP based engine, or a revised engine management system which would cost well over a grand. I have a couple of MR2 friends who are uber smart and they devised a solution called the Grunt Box.

Basically the Grunt Box is a plug-in to your car's ECU that uses the cold start injectors to effectively eliminate the lean condition. The device takes into consideration your throttle position and is only on when you are below 3,500rpm and above 60% throttle. My MR2 was the testbed for the Grunt Box and the hp/tq gains (below 3,500rpms) were significant. The A/F ratio went from 15.7-16:1 to a much more manageable 12.5:1.

I dunno if this helps you all out but I thought I would post up my experiences with SCs and AFM based Toyotas.

 

[GZERO]

I still suggest a wideband o2.

He is right.
I will try to shime in with what i got.

Why are you guys so worried about FPR or even fuel pumps? I think you are all ahead in the game or you just skip a step.

Have anyone been playing with the wideband to really knows what is happening? i'm pretty sure that what most of you are saying that the cruiser runs leans at wot might be right, but in this type of things what we "might" think is not good enough.

When you add boost to an engine you're injecting (for lack of a better word) more air into the system (even if that means 7 psi), now, you're injectors (and even the whole system) weren't designed to auto calibrate themselves. Now, if you slam the throtle open (WOT) there will be more air coming into the engine and not enough fuel (now, remember, fuel is used for combustion, but it also works as a chamber cooler), if there isnt enough fuel we have a lean condition (which translates into high temps). Now is where the 1FZ stands out, pistons temps skyrocket, but the lil thing on the end of the cilinder spraying oil to the piston skirt helps the piston in cooling, but since the combustion chamber is that hot, it gets to a point where everything starts to wear faster as oil starts to break down.

Two conditions that can really destroy an engine:

Lean conditions, depending on how lean depends on what temperatures they will see. Too hot you start melting things.
Rich conditions (pig rich). Everything too rich eats the oil covering the cyl walls and creates more heat by doing this.


Now, the questions, has anyone played with EGTs? or with the wideband? has anyone been able to see the stock ECU maps to see at what duty cycle the injectors are working??

Also, why nobody has tried to add some kind of piggy backs to control injectors and tune the engine?? (off course, this is better than FPR but is still a half ass way of doing things).

I prefer 6 bigger injectores tuned than: FPR, extra injectors or even hacks. But in reality ANYTHING that keeps the numbers on the wideband happy does work.

 

[Romer]

Now this is a great discussion.

Out of all the techno nerds around here someone has the gear to do this, don't they?

If anyone has one of those gauges they want to loan out, I'll do the test. Can't see spending $300 right now, must re-gear first for the bigger meats.

 

[GZERO]

I don't think many people will want to do that. There are tools that can't be lend.

I'm with ya on this. Can you point to a source for it.

Thanks

Ask, and you shall receive.

http://www.innovatemotorsports.com/index.html
http://www.machv.com/plxdewio2se.html
http://www.wmsracing.com/wmsweb/wideband.htm
http://www.diyautotune.com/catalog/wideband-systems-c-23.html
http://www.powertraincontrolsolutions.com/content-26.html

i bet there are alot more, also, somebody should look into ECU chipping.

 

[Lockd97]

The problems with FMU's, lean conditions, and using bigger injectors in the 3.4l community have been well documented. The TRD FMU supplied with the S/C was very inconsistent and TRD dropped the FMU completely. A few people tried various FMU's (Cartech is the one I can remember off the top of my head) with decent success.
What one individual discovered and later followed by TRD was to hook the vaccume line from the fuel pressure regulator to a port that sees boost. I have ran this on the Tacoma for the last 7 years with zero problems. My testing in the beginning verified a 1:1 pressure rise when using this method just like a correctly functioning FMU. Someone want to try this on their 80?

When I installed the S/C on the 80, I just followed TRD's instructions on the routing of the various lines. I have not tried this nor have I welded in a bung for my wideband. I travel way too much for my job and won't be home for the next three weeks so it will be a while before I can provide data but this thread has motivated me.

 

[landtank]

The factory specs say 280-352 cc/min.

The 1FZ is 264-328 cc/min.


Not a lot of difference.

Well Dan, I read where Christo used his SMT6 to run 2 additional injectors. The range he reported was 5-15% duty cycle. From talking with him earlier tonight he mentioned that the 15% was during closed loop and the 5% was during open loop.

Simple math might look like this: 2 injectors at 15% = 30% DC or 5% DC per injector. Now these Supra injectors have a 7% increase in flow over the stock ones.

So maybe these aren't so small after all.

I'm quite sure this is not how to calculate this stuff and there is no need to tell me so, just letting people know what's rattling around my head.

 

[GZERO]

Well Dan, I read where Christo used his SMT6 to run 2 additional injectors. The range he reported was 5-15% duty cycle. From talking with him earlier tonight he mentioned that the 15% was during closed loop and the 5% was during open loop.

Simple math might look like this: 2 injectors at 15% = 30% DC or 5% DC per injector. Now these Supra injectors have a 7% increase in flow over the stock ones.

So maybe these aren't so small after all.

I'm quite sure this is not how to calculate this stuff and there is no need to tell me so, just letting people know what's rattling around my head.

this could work, but then again, you'll need a wideband to really know if you're close to what you should.

 

[landtank]

this could work, but then again, you'll need a wideband to really know if you're close to what you should.

I've come to agree on that these past few days.

I'm not sure how up to speed you are with our Forced history. The Kazuma SC runs the stock fuel system and ECU. The older Safari turbo came with a chip but it was more hassle than it was worth and those guys typically ran the stock fuel system and ECU.

Now both these systems have evidence of being slightly lean at times. Some have replaced the stock fuel pump with a Supra Fuel pump which puts out a larger flow at higher PSI and others have put in a rising rate fuel regulator to force more fuel through the injectors. Both of these have seen positive results measured by the seat of the pants.

My thinking as of now is that the stock system needs just a little help in delivery to work rather well. Not optimum, but well. If it could be confirmed that those Supra injectors would fit and I had a SC, I'd be real tempted to bolt them in. In fact if I can get a confirmation on fit and find 6 on Ebay reasonable I'd buy them for someone else to bolt them in for testing.

 

[Romer]

When I installed the S/C on the 80, I just followed TRD's instructions on the routing of the various lines. I have not tried this nor have I welded in a bung for my wideband. I travel way too much for my job and won't be home for the next three weeks so it will be a while before I can provide data but this thread has motivated me.

If you have the equipment to do the testing, that would be great. Just post up or let me know when your ready.

Thanks,

Ken

 

[GZERO]

I've come to agree on that these past few days.

I'm not sure how up to speed you are with our Forced history. The Kazuma SC runs the stock fuel system and ECU. The older Safari turbo came with a chip but it was more hassle than it was worth and those guys typically ran the stock fuel system and ECU.

Now both these systems have evidence of being slightly lean at times. Some have replaced the stock fuel pump with a Supra Fuel pump which puts out a larger flow at higher PSI and others have put in a rising rate fuel regulator to force more fuel through the injectors. Both of these have seen positive results measured by the seat of the pants.

My thinking as of now is that the stock system needs just a little help in delivery to work rather well. Not optimum, but well. If it could be confirmed that those Supra injectors would fit and I had a SC, I'd be real tempted to bolt them in. In fact if I can get a confirmation on fit and find 6 on Ebay reasonable I'd buy them for someone else to bolt them in for testing.

I don't know much about the forced history. But i have instaled a few sc on the I6 4.5 and because of lack of funds i haven't pursued the truth. Now, i'm planing on buying an 80 and bolt the sc, along with a custom IC (which i don't think is really all that hard to make for this specific aplication) and find out the cheapest way to keep the engine between acceptable parameters. Now, keep in mind i'm in Venezuela, so i'm not exactly sure if our ECU is the same as what you guys get.

Remember that the proper way of doing all this is to buy a programable ECU (ie, motec, microtec, etc.) and get it to a dyno shop so they can tune it. This could be very beneficial and will make the car run the way it should run, with the upside that you could get a few horses here and there on the curve. Off course, i understand that this option adds around 2k to the total which is high as it is.

 

[landtank]

As a follow up to the Supra injector. I received an email from FIVE-O and the Supra non turbo injectors are a direct fit to ours. For anyone looking into larger injectors there is probably more listing for a Supra than our LC.

Unfortunately a set of 330cc Supras ended this morning before I got the email, $31.00 + shipping

 

[cruiserdan]

Unfortunately a set of 330cc Supras ended this morning before I got the email, $31.00 + shipping

That's too bad. New ones are between 155 and 171 bucks a piece, depending on year model selected.

 

[landtank]

That's too bad. New ones are between 155 and 171 bucks a piece, depending on year model selected.

Now I didn't say I walked away empty handed

 

[Romer]

I needed some springs and rear L shocks, so I went up to Slee (ain't I lucky) and Christo took me to his white board to explain the 80 series fuel system. As we know, the 80 computer is smart and can learn. So, when operating closed loop, the 80 monitors the sensors and adjusts the fuel trim accordingly. The 95+ computer is smarter, faster and uses better sensors and that is why sometime the 93/94 80's get lean, they are not able to compensate as quickly.
When the fuel system runs open loop, the system does not use any learned data, but uses a hard coded set for fuel trim that cannot be changed. Running WOT tends to operate at open loop.

Other manufacturers fuel maps are not proprietary and can be modified (re-programmed). Toyota's can not be modified, as far as we know. Think of the fuel map as a duty cycle time for off/on.

Based on when the system goes WOT and I am at full boost, Christo theorized that my stock 130K mile fuel pump was not able to keep up with the demand and the pressure dropped. This is why my brand new Supra fuel pump was noticeable at WOT, it was able to maintain pressure, or do a better job at maintaining pressure. Again, this was theory.

Now adding a FPR or better injectors will not help in the above scenario during closed loop operation as the Toyota computer will adjust the duty cycle to be back with what it is now using the sensors.

Open loop will be just dumping more fuel in at the ROM values. Is this too much fuel??? My current setup does not appear to be running lean at all, so I would guess (GUESS) that larger injectors or an FPR may provide too much fuel. However, this is the part we don't know and actual measurements would help for the open loop operation.


So the bottom line is the FPR and other injectors benefit is what needs to be measured with hard data to see if there is added benefit.

Of course, if we could figure a way to tweak the Toyota Fuel Map, we could really improve the performance of the supercharger.

When Christo adds additional injectors in his turbo set-up, he has a piggy back computer controlling them. He uses his fuel mixture gauge (AWO) and adjusts via his laptop while driving to tweak it. This only controls the additional two injectors.

So, Christo was I paying attention

 

[landtank]

I've got some time so I thought I'd add a little more info to what I'm doing.

As Sumotoy has said many times there are calculations for figuring out all this stuff, it's simple math.

After reading and searching the web concerning the injector sizing I finally got what he was saying. I thought I would give an example here using the SC.

Basically all the ratios are given. If you know how much air is being forced you can calculate the injector size and the HP output. If you know any 1 variable the other 2 are calculable.

So lets take the SC as an example. This works very well as boost is always on all the time, there is no lag. This means it has similar effects on HP outout throughout the RPM range. A turbo's output is coverned by load so it's not quite as easy.

So the stock engine outputs 212 hp and SC'd it's 278 hp (from memory??)

That means there is a 31% increase in HP which would indicate you need a 31% increase in injector size to run the injectors in the same duty cycle as they did before the SC was installed.

The flow of a stock injector is 305 cc/min, so an injector flow of 400 cc/min would put the duty cycle of the injectors back in line with a stock truck.

Doing this would not net you any more power if the system was running well enough to keep up with fuel demand. However it would offer a large amount of room for error within the system and still run properly.

Along with these calculations, Christo's comments on the AVO tuning and the email confirming Non turbo Supra injector fit I bought these today.

EBay Injectors

Won't know for a while if the math proves out but theyu weren't all that expensive either.

 

[landtank]

Open loop will be just dumping more fuel in at the ROM values. Is this too much fuel??? My current setup does not appear to be running lean at all, so I would guess (GUESS) that larger injectors or an FPR may provide too much fuel. However, this is the part we don't know and actual measurements would help for the open loop operation.

I beleive this to be incorrect. If you think about it, if open loop used set values for it's injectors then adding the SC would automatically produce a lean situation because they were set for a NON SC'd engine.

What I beleive to be happenning is that during closed loop the truck learns what to do with the injectors. At some point in the RPM band the ECU can't react fast enough to keep up so it goes into open loop. Here it references the values obtained during closed loop and postulates the duty cycles needed to provide the correct amount of fuel.

I can't think of any other way the truck's ECU could adapt to having a SC added during open loop.

 

[Romer]

Actually it makes sense for open loop. What I didn't mention because it is hard to do in words, is there is a Table (Fuel map), it reads the O2 sensor and applies the corresponding value from the table. A SC engine at WOT will have a different reading than a non SC engine and will take the "fixed" open loop input from a different spot in the table. At least, that was my understanding of how Christo drew it on his white board.

Fixed means hard coded, so two different hard coded data points

 

[sleeoffroad]

Rich, the air flow is bigger, so the truck knows there is more air so the values are taken from a different location on the fuel map. However it does not use o2 sensor data

See

www.autoshop101.com/forms/h44.pdf

 

[Romer]

To expand on the point alittle, thats why 93's have more of a problem at WOT because their sensor setup (Flapper??) is slower so they pick a different point in the table. That's why they tend to be lean at WOT.

Different point here would mean a point with a lower on duty cycle.

The Open loop data has many values and are selected by the sensor reading and the computers action based upon that.

 

[Romer]

Rich, the air flow is bigger, so the truck knows there is more air so the values are taken from a different location on the fuel map. However it does not use o2 sensor data

See

www.autoshop101.com/forms/h44.pdf

Nice reference Christo, thanks for the correction