Suzuki GSXR 750 quad Throttle Body Install on 2.3 L Duratec

[vin0410]

What about Air flow sensor on the air box which encloses the 4 throttles? BMW M engines always use this setup. If it works you do not need a MAP.

[Egz]

Originally Posted by Hocky

You do realize that the original equipment does not incorporate a MAP at all? And that is the main reason why your tuning will not work. You will have to find some way to incorporate a MAF in order to utilize the stock computer and then you've negated any gain that there may have been from the ITB's. That said, there is a lot more math involved than 'hey, this thing has 4 itbs, my car has 4 cylinders... it'll work!' when designed intake/itb set ups.

We actually have a MAF and a MAP. However, the stock ECU system won't run on the MAP sensor alone.

[JohnStranahan]

hocky-I am using the stock Mass Air Flow Sensor in a much larger Cosworth tube. Why do you think this will negate gains. The Cosworth manifold which seems to be the only one available works similarly. It has gains. The main gain I am looking for are due to increased air velocity from the throttle bodies at part throttle. The air jets from the partly closed throttle bodies will be right in the runners keeping the air speed up and then increased high rpm power from the ability to flow more air. The computer seems to be quite flexible.


The engine does use an Manifold Absolute Pressure sensor in conjunction with an Inlet Air Temperature sensor (MAP/IAT)to calculate engine load. Among other things probably this sensor lets the computer calculate when to open the runner tuning butterflies that open at approximately 3000 RPM. There has to also be some kind of base fuel map that the computer modifies in a closed loop using the O2 sensors on the exhaust.
John

[JohnStranahan]

Fordblue03-I plan to use the stock injectors to start with. There is about a 30-40 psi fuel pressure in reserve. This can be raised in small increments to feed more fuel. I will also be able to hook up the motor to a livelink using the SCT tool and monitor fuel trims. Seat to the pants will also easily tell me if there is a bog from lack of fuel.
Note that once you put on that non CARB approved Focus Sport cold air intake you are legally in the same area as I am as far as federal emmisions regulations. That stock air filter is very much part of the system. My plans are to meet emmisions but not the visual inspection.

[JohnStranahan]

vin0410-sounds like an interesting project. Give us a pic of one of your throttle bodies when you get a chance.

[burnv8]

certainley a good project, i couldn't agree with your work more...

Duratec's are not strangers to ITB's, at least not in the UK, you'll be the first on this site i belive to be fitting ITB's i congrats you if you could pull this off, a message to other members "stop worrying about CAI make A vs CAI make B, and start worrying about REAL all motor performance".

[orionlion82]

Originally Posted by JohnStranahan

Fordblue03-I plan to use the stock injectors to start with. There is about a 30-40 psi fuel pressure in reserve. This can be raised in small increments to feed more fuel. I will also be able to hook up the motor to a livelink using the SCT tool and monitor fuel trims. Seat to the pants will also easily tell me if there is a bog from lack of fuel.
Note that once you put on that non CARB approved Focus Sport cold air intake you are legally in the same area as I am as far as federal emmisions regulations. That stock air filter is very much part of the system. My plans are to meet emmisions but not the visual inspection.

as i understand velocity and torque are tied together LOOSELY.

velocity comes frome venturies, funnel shapes, goofy pointless curves and length.

pressure and flow are part B and part C.
this is really complicated fluid dynamics or whatever the science elite call it.

ALLSO NOTE the comment on the first page about the slow tip in.
if you suddenly DUMP lots of air in an engine - especially backing off the throttle and then slamming it down again - like in racing...

your mixture is gonna be all over the place.
bad for the engine, bad for emissions.

super fast plates might make you go rich/lean/rich/lean faster than things can adjust.
especially if you accomplich your velocity and flow goals.

nobody has addressed the basics here and ive only scratched the surface.

freeze! put your hands up and stop the rocket science!

i say engines 101 are in direct conflict.

[fordblue03]

Originally Posted by JohnStranahan

Fordblue03-I plan to use the stock injectors to start with. There is about a 30-40 psi fuel pressure in reserve. This can be raised in small increments to feed more fuel. I will also be able to hook up the motor to a livelink using the SCT tool and monitor fuel trims. Seat to the pants will also easily tell me if there is a bog from lack of fuel.
Note that once you put on that non CARB approved Focus Sport cold air intake you are legally in the same area as I am as far as federal emmisions regulations. That stock air filter is very much part of the system. My plans are to meet emmisions but not the visual inspection.

I know whart you mean about the CAI or similiar. I've decided not to go that route and am considering a engine swap from a newer car, since I hear that is a good loop hole for emissions. It would retain the emission system from the newer engine and be considered legal. Of course the computer would be swaped as well as any other parts neccessary. There is more to it than just a newer engine, like vehicle weight and other factors. I plan on doing some research on it and as soon as I can I will start a thread on it.
Good luck!

[vin0410]

Originally Posted by Egz

We actually have a MAF and a MAP. However, the stock ECU system won't run on the MAP sensor alone.

Then can we run MAF alone? Or both must run together?

[Dan-O]

I actually toyed with this a while back with a Honda.
I enclosed the ITB's inlet in an air box, a HUGE air box, and connected 4 vacuum lines from the TBs together. I installed a 0.030" MIG welding tip to act as a restriction/buffer in the vacuum line before the MAP.
You need a MAP for engine load measurement, you need MAF to measure air flow needs of the motor.

[phongshader]

Interesting project. I'm working on something similar. I'm not worried about emissions as I have a SB100 exemption on my project. I'm casting an intake manifold that the Suzuki throttle bodies will bolt onto with the appropriate hoses. I'm using a Megasquirt ecu for both fuel and spark.
Yes you may be reinventing the wheel but at a fraction of the cost and it's a lot of fun creating an itb set for a couple hundred dollars instead of buying one for a couple of thousand!
http://usera.imagecave.com/system/sh...g&a=Locost_wk4

[Focus_wrc07]

Originally Posted by JohnStranahan

Well you have seen the ad where the Duracell bunny starts the entire East Coast generating grid. I thought they would start the car and be lighter. Just kidding.

John, Duracell never had a bunny mascot. You're thinking of Energizer. That was a good one about being lighter, and everything.

Just keep us posted on progress, and keep up with pics please.

[JohnStranahan]

Dan-O- Well write us a little report. How was midrange, top end. Did you get all the bugs out where it worked smoothly.
Phongshader-thanks for the report keep us posted.
Focus wrc07- Yeah I saw that commercial again last night I remembered everything but the brand. It was a debate that or starting the space ship.

I made a couple tiny steps more progress. I picked up the spectre 4 inch to 3 inch adaptor in black. See the pic below. It is attached to a 4 inch flange inlet from spectre that is made for GM MAF sensors. The 3 inch Focus sport bend is also attached. I will cut this pipe to get my neccesary bend. This will hookup to the already installed customized Cosworth Cold Air Intake.

It is interesting that guys with single throttle bodies see value in cold air intakes, but once you start to put on the quad throttle bodies suddenly "there are no gains." I believe gains will be on the same order for both systems compared to drawing hot under hood air. I don't see why "mixtures are going to be all over the place". The MAF will control the mixture. It will sense different air flow at the speed of sound. The electronics don't feel like they are slowing things down now except for the return to idle.

I got a replacement intake manifold gasket set. As they are individual pieces it was not much help in figuring things out. I assume the two blue seals are around the EGR.

There is about 9 inches of clear space in front of the engine for the intake. Maybe 10 inches. The upper tubes in the photo will neccesarily be short rather than the 3 or 4 inches shown. I can gain a couple of inches by moving the engines radiator fans forward, but would rather not.

[Focus_wrc07]

John, it's cool. I just thought I'd give you a bit of trouble. LOL.

Looks like you seem to be on track, and making progress. Now only if you can make the MAP/MAF work with the quad throttle body setup, you'll be set.

[duggyd123]

this is the dumbest idea i have ever heard of. dude there are so many other ways to do this right.


cosworth coswoth cosworth cosworth. I did i meantion cosworth has the same thing.

[Egz]

Have you seen the price of a Cosworth roller throttle body? This guy is doing the work himself, and saving himself a fortune. Not to mention, this type of setup is done on fair amount of other cars as well. Quite the opposite of the 'dumbest idea'.

[Focus_wrc07]

Egz, thanks for saying it before I did. I just seen it.

Yes, he is saving himself a fortune, and if everything works, we'll have a better understanding of how to do it ourselves to save money, and everything as well.

[JohnStranahan]

My intention was to use the Suzuki throttle position sensor to sense the main throttle blade position. This will require some experiments of which I completed the first. According to my tech the ford sensors normally work on 5 volts. Full throttle will detect as somewhat less than 5 volts. Closed throttle above zero a small amount.

I have a variable power supply that I can supply 5 volts. I connected plus and minus to the Suzuki yellow and blue lead which are low in the pictured plug. I sensed the voltage at the black wire which is high in the plug. Firstly hooking up the power supply drew less than .01 amps. This is good as things are not overheating. Throttle closed was about .010 V. Throttle opening saw a nice smooth increase in voltage to about 4.9 or so fully open. I think the ford computer will readjust to small differences in wide open and full closed as there is bound to be a 5% or so variability in one part to the next. Anyway another short test of the car will see if I am matching closely enough. Use of this TPS will make the assembly neater by requiring less fabrication.
The TPS slides down a flat blade that becomes the throttle shaft. You can see the secondary throttle plate blade which is similar. You also get a spare TPS with this throttle body as the Secondaries have an identical position sensor that will not be used.
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[Dan-O]

For my Honda TPS I modded a stock TPS to mount with the GSX-R sensor.
As far as driveabilty, well, lets just say it was different. Were talking about an '87 CRX with a 1.5 so it wasn't a stump puller with tons of torque. It ended up being a rev motor, in other words it liked to be hanging out above 5K RPMs all the time. But the throttle response was as crisp as a fall day.
This was all before I had kids and now have adjusted priorities. I used to be out on the shop dreaming and creating some kind of project all the time. I ended up scraping and selling the ITB project and ended up turboing it it, again with the stock ECU and a MAP scaler. It worked OK, but I ended up MegaSquirting mine as well. Can't beat the price and tune-ability.
I was fluent in MegaSquirt speak and used to log and tune daily.
I miss my CRX but I do enjoy my ZX3 even more. At least it has a bigger motor and more aftermarket support.

[Oreo]

If he can get all the bugs worked out of the system & document a sizeable advantage of TQ & HP, I'd seriously consider copying his design for myself & selling my Cosworth manifold. 'Specially since I've got the software to do my own tuning now.

[sleeper2]

hey guys look twn sell some.. Look at the bottom of the page, there is for zetec, then for duratec....

http://www.racetep.com/twm2000.html

[Egz]

Originally Posted by sleeper2

hey guys look twn sell some.. Look at the bottom of the page, there is for zetec, then for duratec....

http://www.racetep.com/twm2000.html

Looks like they changed their page. Last time they had a price listed, it was $2300.

[Focus_wrc07]

Has anyone contacted them to see the pricing on those yet?

[JohnStranahan]

I like those Vacuum Accumulators on that ITB. I will make something similar that will go inside the air intake plenum so that air intake temperature will be sensed. I thinking of using a big fuel filter can (2 inch diameter) that I saw on the wall. It has two inlets and is about the right volume.

Baseline Numbers and Numbers with tune.
I took the time today to get some baseline numbers on the 2005 Focus ST. Here are the general specs. Cold Air Intake plus Cold Air Intake Box, 124 wheel HP.

After my SCT tune, lightweight wheels and tires, lowered and running Plus Gasolene I am at 131 HP. These numbers were determined with what I will call my Freeway Dyno. All you need is the weight of the car plus passengers and a stop watch and some Physics. The details are Here in my Journal, Freeway Dyno.

G-tech Data
I now also have a G-tech unit which I used to get 1/4 mile times, 0-100 mph times and backup Wheel Horsepower numbers.
1/4 mile - 16.26 s @86.7 mph
0-100 mph - 21.35 When I add my coast down Horsepower or the power used to fight wind and road friction at 5000-6000 RPM in 3 rd gear (20.8 HP) to the G-tech's wheel horsepower number in 3rd gear at 5200 RPM (110 HP peak). I get 131 HP. There is good agreement between the two methods and good agreement on a chassis dyno for my original 124 wheel horsepower with just a cold air intake which added 8 HP to the baseline vehicle.

I corrected a Horsepower error from the G-tech. I found max HP at 5200 not 5000 rpm. It peaked at 110 there but does not include wind and road drag.

[Focus_wrc07]

John, you are correct on the physics with the weight, baseline power, and everything. It can be complicated for some of those who doesn't know, or understand physics though.