Author Topic: The Rebirth  (Read 136947 times)

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Offline yoshimitsuspeed

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Re: The Rebirth
« Reply #345 on: October 31, 2014, 01:18:59 AM »
Nice build and nice fab work.
I have had a few people come to me trying to make a smaller SC pulley like the speedchaser ones. I usually talk them out of it because that along with an oversized pulley pushes the SC so far outside it's ideal range that I consider it to be not worth the cost. I can see how in your situation not being able to run a big crank pulley means any gains you can get from the SC pulley could be very valuable.
Your design gave me a thought.
I have started working with a Chinese manufacturer who appears to do very solid work. I am continuing to send them more challenging and more precise projects to see if they are as good as they claim.
Since if I remember right there is actually a good bit of room between the pulley and the drive plate it may be possible to make a pulley from the ground up that was a little smaller and therefore allowed the diameter to be a couple mm smaller as well.
Getting one made may still be several hundred but a run of four or so could bring that down to maybe a couple hundred ea.
At least this allows you to run the stock stator and drive plate making the cost look a lot better. Plus making a smaller stator would require some electrical engineering to do right. I think even then it would likely be weaker. Plus you would have to run a smaller drive plate reduces clamping force which makes it much more likely to slip.
Still a bit pricey but I thought I'd mention it. Not sure how far you would want to try to take the idea.
I am not fond of SC14 conversions because just like the SC12 they are only rated to a 1.8:1 PR and even at that are in the 50s to low 60s adiabatic efficiency. The SC14 does improve the efficiency a tiny bit on the horizontal/flow axis but by so little it would be hard to justify.

Offline BigMike

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Re: The Rebirth
« Reply #346 on: October 31, 2014, 10:54:41 AM »
Nice build and nice fab work.
Thanks for the nice comments よしくん

So I originally was considering purchasing a poly-vee cutter for our lathe from http://toolflo.com/cats/AUTOMOTIVE.pdf as a very close friend of ours is a Tool Flo dealer. The cutter is just over $100 but it doesn't fit any of our tool holders so I'd have to also purchase about a $300 holder (sucks!). My idea was to offer a service to the GZE community as follows: Send me your USDM pulley and I'll cut it down to ____  mm, hoping that I could get 10 or 15mm out of it .... but unfortunately the USDM magnet is just too large and there is hardly any room at all to shave material down. The JDM pulley just so happens to use a very small magnet and there is an extensive amount of material that can be turned down on the stock JDM pulley -- we got 10mm out of it without sacrificing any strength. While I could still offer my services for those who have imported the Levin engine, that is such a small market I decided to not invest in the tools and just have our machine shop turn mine down.

When I removed my original pulley and started looking at it, I was pretty bummed. I was hoping to only charge $30? $40? $50? for the service, send me your pulley, I'll return it X amount smaller. Oh well...

As for the SC RPM heat issue, from reply #299 I am working on another homemade Water/Alcohol injection system. Earlier this week I received a new 5 quart container, purchased from here for $16, and now that E85 is easy to get, I'm planning to pump 0.75 gallons E85 and then top off the remaining 2 quarts with water. Should be about a 50/50 mix. In the past I had to drive across town, purchase a 5 gallon drum of Methanol, store it in my garage, make a mess while trying to pour it into a container in my car.  .....having the E85 right at the pump seems like a great solution.

I am fully aware that these old units are not as efficient as modern day SC tech. Bill (Sirdeuce) has both a M62 and M90 that we can play with and the city we live in is home to the 85% efficient Whipple S/C (link). But I don't know... Just something about keeping Toyota parts excites me. With my Rock Crawler, many people like to swap out Toyota axles for full size American axles (D60 is very common) but I really dislike this because it's no longer Toyota, amongst other reasons. I have pride in Toyota, that's why all my cars are Toyota :gap: So for me I find joy in using old, outdated tech. Otherwise I would have just swapped in a Honda K20 and gotten on with my life but then my car wouldn't have a Toyota heart.

Another thing I'll mention ahead of progress to this post is that I am going to re-install my Davies Craig Electric Waterpump (link), so running a larger crank pulley doesn't have the big draw back of overrevving the water pump. Combined with the programmable Parallax Propeller board (link) that I am currently installing, I will fit an alarm buzzer and blinking red LED to monitor my engine temps should they ever go over, what 50% or 55% gauge? (My car never runs over 45% gauge, so even if I set the alarm to 60% gauge ... if it's ever at 60% temp then something is definitely wrong and I'll be alerted straight away). When I used the e-water pump with my sidedraft N/A engine (link) it worked great and should it ever stop working out on the highway, I carried the waterpump pulley and original belt in the frunk for a simple roadside swap back to mechanical driven cooling. So just yesterday I told our machinist to hold off on milling down my 165mm crank pulley. I think I am going to keep it large and somehow install a new timing pointer near the stock pointer location so the smog guy will still be able to check my timing. While R&R the crank pulley every 2 yrs for smog is not difficult, the pointer is awfully difficult as you know it is mounted to the timing belt tensioner and I have to remove my A/C bracket to get the front plastic cover off (or not install the bolts on that side of the engine).

Ahhhhhh decisions decisions. My water/E85 injection will also be controlled by my Propeller board. I plan to program a progressive (temp based) duty cycle so it can be reliable and also long lasting for long road trips (rather than using my old on/off boost switch that would cycle through my 5 qt container too quickly). Hopefully I can go a few gas tank fill-ups between water inj tank refills. Also, I'll be using the Propeller in lieu of a Grunt Box, and am going to experiment (the Propeller will also be datalogging from my wide band O2) between using the cold start injector or water/alc injector to cope with the low RPM lean-out condition.

Ahhh so much to do! Can't wait to get this all done!! First things first, I need to start with the Propeller somewhere, and the most clear choice is with the exhaust system. So on to the next update!
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Offline BigMike

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Re: The Rebirth
« Reply #347 on: October 31, 2014, 10:55:06 AM »
Oct 19, 2014: Installed 2-bar MAP sensor to exhaust system

I drove the car on the new rebuilt engine to San Jose and it did great. Made 28 MPG combined city/highway + goofing around with the new setup. I am happy to report that peak boost is now up from 10 PSI to 11.25 PSI from the new 8.5% smaller S/C pulley. I still have my 165mm crank pulley to install, which is 13.8% larger, so following this ratio this would put me at 13.53 PSI. Of course the losses grow with RPM so if I can make 13 PSI with the larger crank pulley then I'll be a happy camper :)

Ran some compression numbers and here are the results:
Cyl    Before...      After...
1156 PSI166 PSI
2146169
393169
4107169

:woohoo:

Throttle response is definitely am improvement and the boost builds much, much faster than before. Revving the engine in neutral, I used to get about 3 PSI, now it hits 8 or 9 PSI from just whacking the throttle! The intake is also much louder which I love but the exhaust is just too loud, which I am aware of, which is why I gotta get this exhaust throttle hooked up and operational!

So here come some pics!

First, I knew that the TRD 2.125" pipe dumping into a 2.5" pipe is no good but I just wanted to get the car back on the road. So I took it back apart and got this taken care of. I simply ground the outlet of the TRD pipe with a smooth radius so that it matches the 2.5" exhaust gasket I'm using (link).

I also don't like the TRD spring-loaded flex ball-joint because as Bill points out it can expand and loose exhaust pressure at high RPM and also the male end has to taper down to a smaller ID in order to not pop out of the ball-joint. So I am thinking about getting a steel flex joint similar to this one and replacing the dumb TRD joint. Especially if the TRD ball-joint does in fact let exhaust gases out, then it will throw off my pressure readings!!
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Offline BigMike

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Re: The Rebirth
« Reply #348 on: October 31, 2014, 11:13:33 AM »
Oct 19, 2014: Installed 2-bar MAP sensor to exhaust system (continued)

Lastly, here is the 2-bar MAP sensor's new home! I originally got a new style GM 2-bar MAP sensor (P/N 12569241) from NAPA, my cost was just over $60!! Then Chee (stupidfast) told me about this eBay auction, http://www.ebay.com/itm/121013486440, which is the old style GM sensor for half the price. It's an unknown brand (made in China for sure) so it is a gamble and returns will be far more difficult to deal with should it stop working. But I decided to give it a shot-

I didn't get any pictures of installing the line, but basically I took a 1/4" OD hydraulic line, bent it as needed with a brake line bender, drilled a hole in my TRD pipe, ground away the ceramic coating, and welded it in. Brazing would have been better but all our brazing equipment was put away and I already had the welder out so I just welded it. I then used a 8mm silicone hose I got from SiliconeIntakes (link) (I probably should have gotten a 6mm hose), which has a max temp rating of 350 degrees F (177 C). The idea of using the brake line is to get the hose mounted to the exhaust a certain distance away, allowing the brake line to cool between the hose and the exhaust pipe.

Second pic shows a close up of the sensor mounted and wired. Black is a simple ground, green is the signal Vdd output, and red is a 5 volt input. So, where to get 5 volts? I already have L7805CV voltage clamps (link), but Bill gave me a GREAT idea and that is to use the 5 Vdd coming from my ECU that powers circuits like the throttle position sensor. Knowing this is a nice, heavy wire, Toyota designed it to support some amperage so running a simple MAP sensor won't be any problem.

The last picture shows the red wire coming up to the ECU. It is connected to the wire discussed above, yellow, from the right ECU plug. I checked the wiring diagram and verified 5 Vdd and hooked it up. Turned key to ON position, checked voltage output from the MAP sensor, was a prefect 2.5 volts (or zero back pressure as the engine was off and pipes cooled down), done!
« Last Edit: October 31, 2014, 11:47:53 AM by BigMike »
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Offline BigMike

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Re: The Rebirth
« Reply #349 on: October 31, 2014, 11:27:23 AM »
Results!!

So I extended and ran the green wire up into my cab where I've been monitoring it using my hand held volt meter. The refresh rate of the volt meter of course is too slow but to just get a basic idea, as I've not hooked up the microcontroller yet, I can see what the exhaust is doing.

So far the data has been sporadic at best. (Is the TRD ball-valve to blame? Or just the slow refresh rate of my digital meter?) As this is a 2-bar MAP sensor with a 0-5 v range, 2.5 volts is 1-bar (or 0 PSI gauge pressure) and 5 volts is 2-bar (or 14.69 PSI gauge pressure). At an idle I've seen both 2.5 volts and over 3 volts. Then I've seen as high as 3.9 volts (8.23 PSI) at near redline, full boost, and also 4.2 volts (9.9 PSI!!) just cruising at 40 MPH. How can back pressure be higher at simple cruising speeds? :headscratch: I know there will be many variables including heat that is affecting the pressure reading, so I am already writing code for the Propeller that will use delayed and averaged throttle angle adjustments.

One thing I'd like to add is that I do have experience in this field. For my circuits lab in college, my semester project was this very device on a Yamaha YZF600R. I had one partner and we used a Parallax BASIC Stamp (link), which is less sophisticated than the Propeller, and it worked great. We simply attached a spare SR20DE throttle body I had directly to the end of the bike's tail pipe, and used an automotive MAP sensor to operate the throttle body with a standard R/C servo (the servo approach which I plan to use again). It was great, the bike was extremely quiet at cruising speeds and then as you went full throttle it would start off quiet and then progressively get louder and louder all the way to redline. I still have my old program, it's in a different language, P-BASIC, but many parts of it I've already carried over into the language of the Propeller which is called Spin. :yesnod:

I don't want to make too many assumptions until I get some real numbers. The first thing I need to do is get the Propeller installed to read the exhaust pressure voltage, throttle TPS voltage, and engine RPM. Then I will have enough data to know if this is going to work on an actual car exhaust or not.

Why 2-bar? It was only a guess. Does exhaust back pressure in an exhaust of this size exceed 14.69 PSI? Do I need a 3-bar? I won't know until I start logging data. As these are 0-5 volt sensors, the higher the range the sensor has, the less resolution I'll have to work with. So hopefully I don't need a 3 or 4 bar sensor, or whatever. I'll be able to be more precise with a 2-bar so I went with it first. To get a baseline, one thought is to install my stock exhaust and do full RPM runs while collecting data. Then, reinstall my new exhaust and adjust the exhaust throttle so that it runs the same back pressure (or ideally higher) as the stock system when I'm just normally cruising around. I haven't done this yet, but, because I'll have to smog my car by next Feb, I'll get the chance soon enough. ;)

In case you are wondering why I am basing the exhaust throttle off of exhaust back pressure rather than throtle body throttle angle via the already existing TPS, consider what would happen with a low back pressure exhaust system and cam timing with increased valve overlapping (for top end power) when you roll into the throttle in 6th gear at 2,500 RPM. Without back pressure, incoming intake charge will easily escape out with outgoing exhaust charge resulting in a loss of bottom end torque. Hence why big exhausts and big cams loose bottom end and have poor idle characteristics. So if I based the exhaust throttle on my intake throttle, then the exhaust throttle would respond at low RPMs when I don't want it to. So rather I need to base it on the back-pressure itself.

Alternatively, it can be based off of a look-up table which I have also begun programming. I'll need to get some data collected first, but I plan to have two circuits just like the ECU, open and closed loops. If you are really on it, racing around in the hills, I'll be going from full throttle, then zero throttle for gear shift, and back to full throttle ... so the exhaust back pressure is going to be all over the place. Therefore I am planing to use timers and other metrics, such as engine RPM and engine load, to determine if I am going to read from the exhaust MAP sensor or switch to a pre-defined table of values. :thumbs: :thumbs: :thumbs:

Regards,
BigMike
« Last Edit: October 31, 2014, 12:38:58 PM by BigMike »
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Offline yoshimitsuspeed

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Re: The Rebirth
« Reply #350 on: October 31, 2014, 05:49:03 PM »
The Eaton M series are a tiny bit more efficient but not all that much. Not enough to be worth switching to in my book.

It has always pissed me off that Whipple claims 85% efficiency but any map you find for their product shows not much better than the 60s.
I feel like the twinscrew manufacturers twist numbers a lot more to make them look more competitive with turbos when they are not. They are slightly better than roots but I have yet to see one that is significantly better.
After extensive discussion with Sprintex I did learn that they act as a big heat sink which means that while they are absorbing the heat they are making they can have outlet temps lower than their rated efficiency would expect but once they are heat soaked they will crank out very hot air and can quickly get dangerously hot. This means that for high pressure ratios they can work okay on drag cars or dyno queens where they have time to cool down after a short pull but are not nearly as well suited to extended use unless the pressure is kept much lower.

http://i11.photobucket.com/albums/a155/elbigjer/whipplew100axmap.jpg

Whatever the case if you are keeping the pressure ratio low like you are then it's not a bad choice. You will have more outlet heat than a turbo would but at 10 PSI it's not hard to get rid of most of it. water/meth injection will also definitely help.

I'm not sure what your budget or goals are. Most people aren't interested in going into the motor but in a case like yours where making power at limited boost is concerned one of the biggest things you can do is increase the compression.
I have not studied the effects of compression on emissions but I would think as long as you kept it low enough to maintain stock cams and ignition timing you should be able to pass. Bigger cams would help making more power per PSI and allow you to run even more compression but I don't know how much cam you could run before being noticed or failing the sniffer.
I am used to tuning on 91 at 6k feet so I usually figure it's not much harder than tuning near sea level most places that get 93 octane but I'm guessing you only have 91 and at sea level that still limits things a bit.
Still though even on 91 I bet you could run around 10/1 at 10 PSI.
That's all hypothetical but I'd be confident enough to try it on a motor of mine with stock 16v cams. I'd just want good detonation monitoring.
If you are doing water/meth injection then you could set it up pretty near the limits of detonation without it. Just good enough to pass emissions and not blow up if it ran dry or failed.
Now I'm interested to know more about the effect of emissions on compression.
All the good articles I found in a quick search was on diesel though.


Offline STUPID FAST

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Re: The Rebirth
« Reply #351 on: December 11, 2014, 04:51:47 PM »
all this work for just to run 14's lol

Offline Sirdeuce

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Re: The Rebirth
« Reply #352 on: January 28, 2015, 06:33:44 PM »
Not the 1/4 mile time that is important, or how fast you go. It's what you actually do to get there!
"I slept with faith and found a corpse in my arms on wakening; I drank and danced all night with doubt and found her a virgin in the morning."

Offline BigMike

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Re: The Rebirth
« Reply #353 on: February 18, 2015, 11:36:41 AM »
Just realized I really need to get this thread updated :hammerhead: Been busy over here :wave: Just got my car smogged last week so it's currently 100% stock... for... another... two days :gap:
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Offline BigMike

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Re: The Rebirth
« Reply #354 on: February 28, 2015, 05:41:46 PM »
Updates!!

I have finally made a new YouTube page just for my MR2! Check it out here: https://www.youtube.com/channel/UCcSHTQxPVyDHGhJR1prL68g (Google/YT have really upped the requirements for a custom channel URL so for now this ugly link will have to do)

Let's see... Well, a LOT has happened since October 19th :gap:

Oct 20, 2014: Improved flow through exhaust throttle

The next day I pulled the throttle off and ground it down to open it up / improve flow.

Oct 21, 2014: Fixed water & oil leaks, New Front Bushings

The day after that I fixed a water leak (had a bad radiator petcook), finally got the new front bushings installed, and addressed an oil leak.

The oil leak has been quite annoying. It resulted from when I plugged off the driver's side axle seal to clean the transmission when it was out of the car. I happened to pop the spring off the backside of the seal and couldn't get it reinstalled from the outside-in. So I had to remove the seal, place the spring back in it's grove in the back of the seal, and then reinstall the seal. And yes, I know it's risky to R&R seals but at the time I just wanted to get my car running and there was always a chance I'd get it back together okay.

So fast forward to Oct 21 and I bought a new axle seal from the dealer, drained the transaxle, removed the old seal (which I'd installed new during the 6-speed conversion), and when I went to install the new seal, RETARDED me bought an original seal for a 1987 MR2 -- WELL IDIOT I don't have the original transaxle anymore now do I :smack:

So, I reinstalled FOR A SECOND TIME the leaking seal and added silicone around it's OD got good measure. I am 99.9% sure it's gonna leak and I'll have to drain the whole thing all over again :slap:

The bushings installed great. I spent extra time really cleaning up the bushing mounts on the chassis, being sure to remove all traces of the 27-year old original bushings. Also cleaned up the threads on the control rods and added a lot of anti-seize to prevent rust and make for painless alignment adjustments. I'll need to get everything realigned before I come to a full conclusion but I want to wait until I get new tires....
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Offline BigMike

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Re: The Rebirth
« Reply #355 on: February 28, 2015, 06:33:09 PM »
Oct 22, 2014: New shoes and re-aligned!

Moving right along the very next day I got new tires installed :booya:

I've always been a Bridgestone guy (Japanese-company and made in Japan!) and my outgoing Potenza RE-11 have been the best tires I've ever used. I installed my old tires two years prior, back at reply #252, when I had 268,400 miles. So I managed two years 3 days and 29,236 miles on these tires which included driving for multiple months with known bad rear alignment and no rotating

30k miles from "200" treadwear and "AA" traction-rated soft tires with all the crazy driving I do? I'm happy with that!! That's 60-cents per day to have arguably the best DOT tires in my tire size. So worth it!

Also got the alignment done (of course) and yeah the rear was waaaaay outta whack. I need to find the paperwork but the new alignment was really strange in the front. I requested to have a negative 2.0 for both front ends and this is what the report listed:
Before: -1.9 / -2.1 (left/right)
After: -1.5 / -2.0

(at least I think this is what it was, I gotta find my paperwork to be sure, but I remember it was similar to this)

I looked at it for a moment and said, ummmm Why is the driver's front only -1.5? And he said that was the max he could get. Clearly the before reading showed more than this so what was he talking about? Well, I'm maybe too nice of a guy and I gave him a dirty/strange look and then just said Ok thanks and left. I guess I should have demanded they put the car back on the rack? and then what, they might screw it up even more because I'm being "picky" ? Anyway, I'm still happy, it's more camber than what the stock suspension could muster! (see my thread Simple DIY Extra Camber for how I modified my front suspension for more negative camber)

Ohh, I almost forgot, Bridgestone updated the RE-11s to a new "RE-11A" model. According to Tirerack's description,
Quote from: Tirerack
"Sharing the tread design of the popular Potenza RE-11, the Potenza RE-11A adds an exclusive tread compound that combines silica with a new long-link carbon black to increase road contact and abrasion resistance while promoting tread rubber flexibility across a range of cool to hot temperatures."

I can't say I notice a difference with the updated "A" compound because...
1) The tires are new, larger diameter, and nice and soft.
2) I also installed new bushings so its very different now.

Which brings me to the new bushings. Now that I've got 100% new bushings all around, here is my review of them: They are softer, car feels less responsive, and I've gained body roll. I felt it straight away even before changing tires. And this makes sense. I mean the old bushings were SO LONG GONE and had become very hard and from the constant tightening and tightening and tightening for all the alignments I've had over the years, it was to the point that it was nearly like metal-on-metal. I think it was just all the hype that you read about, all the marketing and improvements new bushings are supposed to make. I think this is comparing good useable stock bushings, not highly worn out and brick-hard bushings.

Nevertheless, the car rides much smoother, less vibrations in the steering wheel, and it rides over off-kiltered dips in the road much better. I can tell the car feels more firmly connected to the ground, it just has a slight delay in feedback that I didn't have before.

Last image: 300k here we come!! :party:
« Last Edit: February 28, 2015, 07:00:50 PM by BigMike »
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     My 1987 Supercharged 4A-powered 6-speed MR2

Offline BigMike

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Re: The Rebirth
« Reply #356 on: February 28, 2015, 08:25:24 PM »
Oct 27, 2014: Mounted Servo to exhaust!

It took 15 days after building the exhaust to get the servo hooked up. It's not powered or being controlled yet, just installed. The original, rather large DC motor that came with the throttle has a planetary reduction drive which makes it near impossible to move on its own. Therefore all this time I've just had the exhaust set at the full open throttle position, and I'm going to do the same with the servo, however the servo is much easier to move to it remains to be seen if the throttle will behave and stay where I set it between now and whenever I can it connected to the micro controller.

On to some pics!

Pic 1: Here is the servo on my old, trusty Axial AX10 Rock Crawler. This is a very nice servo with a crap load of torque for a 1/10th size R/C servo. 333 oz-in torque to be exact and uses titanium gears (specs). This servo is most likely overkill for this but I figure I hardly ever use the Axial for R/C Competition anymore (I did for a while, which is why I built it -- see a sweeeet video of it in action when I first built it here) so what good is it doing sitting around in my garage when it could be powering a SWEEEEET 4A-GZE EXHAUST SYSTEM :beerchug:

Pic 2: These are my pair of NTE962 6-volt Voltage Regulators I ran during competition, capable of 2-amps continuous / 4.4-amps peak draw (which is plenty) (data sheet). I used this to power the servo on my Axial, which is how I was getting over 300 oz-in of torque from it. Well, guess what? I need these guys anyway because I can't run the servo on my car's 12 volt system so it's perfect!

Pic 3: Here I am tearing my ol' friend's steering system apart

Pic 4: Mounted to the throttle plate! (I can't tell you how many times I've removed this throttle in just these few weeks! :ack: )
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Offline BigMike

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Re: The Rebirth
« Reply #357 on: February 28, 2015, 08:34:05 PM »
Installed!
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  246

     My 1987 Supercharged 4A-powered 6-speed MR2

Offline BigMike

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Re: The Rebirth
« Reply #358 on: February 28, 2015, 08:49:37 PM »
Oct 29: Fixed my infernal S/C switching relay issue!

So ever since I got the car running May 2010, I've burned up three or four of these awesome compact-type automotive relays. (Been finding them in late model Toyota's in the wrecking yards.)

Then one day about a month ago I was driving to work and went to make a lane change on the free way and somehow I was boosting 2 or 3 PSI despite the Supercharger being turned off. I was like...... Waaaaiiiiiiiiiitttt a second here. I remember cycling the S/C on and then back off, gave it some gas, and nothing, just 0 PSI like it should be under normally aspirated power.

So little by little I was able to narrow it down that it wasn't a short anywhere in my wiring by rather FOR SOME CRAZY REASON back in 2010 I installed the relay through the backend of the S/C pulley, through the grounded side of the pulley. So when the relay was switched off, power was still going to the S/C relay and partially charging it's magnetic field :willynilly: which was smoking my lil relays and murdering them!

It took a lot of head scratching and a huge mess of wiring to finally figure this out!! Now I have the relay on the proper hot side of the S/C pulley so that once the relay is switched off, no matter what, when the ECU wants the S/C switched on IT IS PLAINLY S.O.L. Ahhhhhh FINALLY.

Pic 1: A lot of work to eventually find the issue!
Pic 2: The relay now on the proper (hot) side of the S/C magnetic clutch pulley :smokin:

And lastly, dun dun dun, the Throttle came off yet again and, drum roll please, THE PROPELLER HAS MADE IT'S FIRST APPEARANCE!!!!! :boobs: .....however I ran out of time and had to put the throttle all back together and drive home :tease: But it's getting closer to having my own on board programmable micro controller! I can almost feel it!
-/_/___/__________\___\_\-
|______________________|
|-------\___________/------|
```````````````````````       
R135
└┼┼┤
  246

     My 1987 Supercharged 4A-powered 6-speed MR2

Offline BigMike

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Re: The Rebirth
« Reply #359 on: February 28, 2015, 09:08:29 PM »
Dec 5, 2014: Got the first line of code operating the servo!

I was gone to Japan for half of November and as such didn't do any work to my car :gap: But when I returned I was very eager to get this Propeller hooked up and here it is in operation for the first time!!

<a href="http://www.youtube.com/v/DHjyQ6hNwaQ&amp;hl=en&amp;fs=1" target="_blank" class="new_win">http://www.youtube.com/v/DHjyQ6hNwaQ&amp;hl=en&amp;fs=1</a>

I found the positional limits of the servo's sweep range of fully closed to fully open throttle and wrote a simple test program. Let me see if I kept it, hang on...

...ok I found it!! Check it out:

Code: [Select]
int main()                                    // main function
{
  servo_angle(16, 720);         // Exhaust fully closed
  pause(2000);
  servo_angle(16, 1535);        // Exhaust Fully Open
  pause(2000);
  servo_angle(16, 720);         // Exhaust fully closed
  servo_stop();
}

And that's that! Now I just need to get it all wired in and I can begin dialing it in with feedback from the MAP sensor! :party:
-/_/___/__________\___\_\-
|______________________|
|-------\___________/------|
```````````````````````       
R135
└┼┼┤
  246

     My 1987 Supercharged 4A-powered 6-speed MR2