93 2.4l DOHC Shadow

[turboshad]

This spring I will be building some chromoly control arms for the Shadow. Besides the fact that I just like building things, they should be benificial in unsprung weight, ability to raise roll center after drop and provisions for caster adjustment.

Currently the deign incorporates 3/4" MM rod ends (actually FK's JM rod ends which cross to the more popular Aurora MM units), a 3/4" Aurora PWB-T shperical bearing in place of the ball joint and 1" .065 wall chromoly tube.

I have figured that loading on the arm is limited by tire traction. From what I can find, road tires have a coefficient of friction (Us) of around .8 and drag slicks can be around 1.2-1.4. With a 2800lb car and ~60/40 split that puts a normal force of 840lbs on each tire. Using a Us of 1.4, the force on the upright bearing at the axle will be ~1200lbs. Without having my car out of storage to measure yet, I figured there would be about an 80/20 ratio from the axle to ball joint and axle to the strut mount on the frame. This means 80% of the 1200 will go through the control arm which is ~1000lbs. For this reason I have used 1000 lbs as a force in all my simulations including braking. Theoretically, my braking forces will probably be less since I will most likely only be getting to that limit on street tires which have a Us of .8 but with the added weight transfer to the front it might not be far off.

After a couple interations and FEAs trying it without bracing, with bracing, and with 1/2" rod ends I have come to this which weighs in at ~ 4.75 lbs. I guess to be honest I haven't weighed the stock cast piece so maybe my weight advantage is a pipe dream. (Passanger side being displayed)



The worst case seemed to be under acceleration with the 1000lb force. The first picture is an overall view with distortion magnified by 50 times with the maximum displacement (which is at the spherical bearing) being 0.03"



The next is a factory of safety chart which goes like this 1(red)<= FS <= 5(blue). So anything red is below a factory of safety of 1 and anything blue is above 5. The in between is shown in the gradient. For those that don't know, below a FS of 1 the material will yield and permantly deform.



The last is an iso clipping of the FS chart that shows the areas below a FS of 3. From this view you can barely see anything below 2 which is why I did my clip at 3.



If there is anyone with more experience than myself in this department I am open to any comments on the design and my theory especially in the determining of forces. What I have displayed will not neccesarily be the final design but I think it is a solid model in the interation process. I still think there is some added strength to be had with minimal weight gain which may increase my margin of safety.

DJ

[turboshad]

So I got the car back from it's winter storage place a couple weeks ago and started on the suspension. Currently I have an Eibach Pro kit but it was a little weak for me and I wasn't happy with the cars stance. So I found a Ground Control coilover kit for rediculously cheap and have started the install on that. Once the car was back I measure the motion ratio of the front and rear and came up with 380lb/in springs in the front giving a frequecy of 1.8Hz and 300lb/in in the rear with a frequency of 1.9Hz. Since I have 380 and 250lb/in springs I will get the 300s which will allow me to have a soft and hard set. If I use the 300s up front and 250s in the rear I get frequencies of 1.6HZ and 1.7Hz which will be a smoother ride for long hauls like if I can get it out to SDAC in Cincinnati this year. I started a thread at TM.com on some motion ratio/spring rate stuff that you can see here if you are interested. http://www.turbo-mopar.com/forums/sh...ad.php?t=35434

I have more or less finished the coil overs with just the rear axle needing painting. I definately like the stance better now and I'm excited to see what the ride will be like. :grin:
Like everyone else that has done this I cut the spring basket off the front and then machined it down to keep it neat. Then I just made a couple 1/4" aluminum washers for the perches to sit on and for the top rubber isolator to back up to.







Here is the front installed.



For the rear I did something similar to CS Racer off turbo-mopar.com and made a 15deg piece to help angle the spring to be more in line with the top perch. Instead of an aluminum piece I made a steel one and welded it to the trailing arm.








I am also starting on some chromoly control arms. After a few interations I have finalized the design and should be able to begin building them decently soon. They should be done for late spring or early summer. Here is the final design overlayed on a sketch of a stock cast arm and a 17" wheel. If you are interested there is a more in depth thread over at TM.com. http://www.turbo-mopar.com/forums/sh...ad.php?t=34943




The next project was getting my AVCR mounted into the dash a little nicer. In the fall I just wanted to get it working and have fun with the car so I used the supplied mount which was pretty bad looking. So I got rid of that and mounted it flush into the dash. If you have never done this before, the trick is to trace out the shape of the piece you want to mount and then cut a hole in the vinyl slightly smaller so the piece will stretch the vinyl when it goes in. Once the vinyl is cut, you need to cut the material underneath to make room for your piece. When you cut the plastic portion go slowly so you can get a real snug fit and then you won't have to do anything else to secure it. My piece is held in purely by fit and takes a pretty solid push to make it go through. Something that isn't needed for it's operation.

This is how it looked before.



And this is how I got to having it flush mounted.





I skipped a few of the cutting material steps here since I forgot to take the pics while I was working but I think you get the picture. I think it looks much cleaner now. 8-)

[turboshad]

ROFL...........that actually crashed my computer.

Well, that's it for what was on the org. I have some spring updates to do which I'll get on tomorrow or in the next couple of days. I think that's enough posts in my own thread for one night though

[CSXRT4]

such an awesome build

probably the coolest p-body ever, you did an awesome job.

[BadAssPerformance]

+1 Awesome work DJ!

[Aries_Turbo]

that thing is killer and it was nice to see it at SDAC.

the build thread does make me think of a few questions.

did you go with the lower spring rates to drive it to sdac?

do you have any knock feedback to the MS?

Brian

[rbryant]

BTW congrats on being featured in the reader's rides page in the August version of Modified Magazine!

It arrived last week while I was on vacation and I just saw it today.

-Rich

[turboshad]

such an awesome build

probably the coolest p-body ever, you did an awesome job.

Thank you. I went back to your log you had going and all the pics are gone. Boo urns. I've done some more work on the ignition map and have pulled alot of timing out of what I had posted on your thread. I don't know if this matters to you but I thought I would let you know.

+1 Awesome work DJ!

Thanks JT. It was good meeting you and so many others at SDAC. I think putting so many names to faces was worth the trip in itself. I think I heard that you were running a mitsu timing belt tensioner that you set and forget. Is that true? If so I would be interested in what you used since the SRT4 has some drawbacks.

that thing is killer and it was nice to see it at SDAC.

the build thread does make me think of a few questions.

did you go with the lower spring rates to drive it to sdac?

do you have any knock feedback to the MS?

Brian

I left the 380/300 spring combo in for my drive. It turned out to be quite managable and not too rough at all. I am currently quite happy with the spring combo and how it drives.

I don't have any knock feedback to the MS. There is provision for it but so far I haven't heard of anyone having any real success using it. Most of that seems to stem from finding proper sensors and driver circuits to dial in the knock frequency to something the MS can utilize. I'll post more on what I am now using for knock hopefully today. And I gotta say it is probably the next best tuning mod next to a WB now that I have tried it.

BTW congrats on being featured in the reader's rides page in the August version of Modified Magazine!

It arrived last week while I was on vacation and I just saw it today.

-Rich

Thanks man. I have heard it made it but since I don't subscribe I still have to wait another week or so for it to hit the news stands. I'm pretty excited and honored that a magazine as focused on the tuner seen and especially imports would consider a Shadow. That's one more check off the list of things I wanted to accomplish with the car. Pretty much all that is left on my list now is getting into the 11s on a full interior daily driver.

[BadAssPerformance]

Thanks JT. It was good meeting you and so many others at SDAC. I think putting so many names to faces was worth the trip in itself. I think I heard that you were running a mitsu timing belt tensioner that you set and forget. Is that true? If so I would be interested in what you used since the SRT4 has some drawbacks.

I am using a spring loaded one, not sure which application it is from, it came with the project motor when I got it... will see if i have a pic

[turboshad]

I am using a spring loaded one, not sure which application it is from, it came with the project motor when I got it... will see if i have a pic

If it's sprung then it doesn't sound like the one I was hearing about. This one would be more like the 8V tensioner where you set the tension and lock it in. It doesn't rely on a spring to keep the tension so you don't have to worry about that failing. I would still appreciate a pic if you come across one though.





Here's an update of what I did this spring.

After a winter's worth of though I became uncomfortable with an open oil pickup. Even though there should be nothing in the sump, if I ever broke something a screen may just save the rest of the engine. So I redid the bottom of my pickup to include a screened box and then lifted it off the floor of the pan a bit more to make sure it had the flow it needed.



I also figured that since the pan was off it would be a good time to put a bit of baffling in. I only baffled for cornering but I think that is where I would run into an issue if anywhere.



I also came across this dead sexy boomba fuel rail that a buddy was selling and it just matched my combo too much to pass up. Being that it is from an SRT4 I had to make a couple tabs to fit it to the neon intake runners. It was well worth the effort though since I think it really adds to the visual apeal of the engine.






I also wasn't happy with the pedal feal with the ford 65mm TB. It was hard to even tell when I was pushing on the pedal which made it difficult to know when I was coming on the throttle especially when starting. It was an easy fix with a spring to give a bit more feel to the pedal.



One thing I had to do in the spring was to pull the clutch since I found the center hub of my disc had some how come loose and was making a real racket. Knowing the warranty claim would take a while I picked up a 4 puck with purple plate from TU and put that in to get me going. The one I removed was a yellow plate which at the time was the strongest I could get. I knew I would out grow it so having to changed clutches to a stronger one wasn't that bad of a deal. On a side note, Chris at TU treated me very well and warrantied the disc. I don't know of any other vendor that would do this for a customer after he had owned it for a year and a half. I had only put on a tad over 1000 miles but most places would have told me tough luck. TU's customer service was top notch including him letting me put it at his table at SDAC to try and sell.



On a rookie error of my own I mis-torqued the cam bolts and ended up sheering off the locating dowel of the intake cam. The only cams I had in the garage were 2.4l so I now have a 2.0l exh. and a 2.4l int. I'm not sure what I like better but I think I will tune the 2.4 as much as I can and see what it does. Then I'll swap a 2.0 int. back in and see if I can do better.



Previously I had an the 255 lph HP Walbro pump from my 89' adapted for 3/8" lines in the car. Well I couldn't get it to seal where I had welded things up so this spring I picked up the newer style pump to use the original 93' system. It is working much better with no leaks.





Now to adress the issue of detecting knock. As I mentioned I don't have any KR feedback on my MS. I was going to build the corny looking setup where you run some tubes to the engine bay and then have some headphones in the cab like an extended stethascope. Then I came across people using a microphone for an electronic stethascope. I liked this idea much better but it still seemed a bit hokey. I bought a mic I thought would work and then I read that someone had found a flat response knock sensor. This is essencially a piezo electric microphone that outputs over a large frequency range unlike most knock sensors which are filtered to a specific band. This was by far the best thing I had seen to hear knock so I sourced them out to be in VWs but figured it would be a tough find and new they were $150. Well after a trip to the wrecker I found that almost any 90 and up VW had them and they sit right on front of the engine for a 30 second removal. I picked up three of them for $5 which was much less than $150. The use an 8mm bolt but there is enough material to drill it out for a 10mm bolt. I got it installed just before my trip to SDAC and I must say that you can hear pinging as clear as day way before you would ever hear it in the cab. It is the best tuning aid next to a WB that I have put on my car so far and I feel way more confident in pushing things in boost when I can hear things happen so soon and so clearly.


Here is the sensor.



This particular one is a Bosch 261 231 013. I found that any 261 231 *** is the same sensor. The last 3 digits just denote the type of pigtale. The VW one is nice because you can grab the sensor with the long lead as well as the factory plug very easily.





I mounted mine in the ceneter of the block so I wouldn't get any valve train or injector noises. The sound is very clear and uncluttered so there is no mistaking when something happens.



Then I brought a shielded cable inside and wired it to a 1/8" headphone jack. I run this into the mic input on my laptop. This aplifies the signal so you can use the headphone out on the laptop to listen to it as well as record it if you like. You also need to wire in a resistor inline so it doesn't distort with the increased sound at higher RPM levels. I think I used a 33K resistor but can't remember. The best would be a 0-50K pot so you could adjust it for the best signal.




Lastly as most know I made a trip to SDAC19 this year and put on over 4600 miles. She ran like a champ with only one minor problem where the bolt attaching my drivers strut to the bearing plate came off. It could have been way worse but nothing was damaged and I was able to just put the strut back in and bolt it back up. Here are a couple pics that Mary Beth (dodgeshadowchik) took that turned out really good. She obviously is much much better with a camera than I am. Thanks for the shots

Myself and Mike_M on our way to Cincinnati from western Canada.



Pictures at SDAC courtesy of Mary Beth. Thanks again.

[Aries_Turbo]

i had a feeling that you were going to say something about listening to knock via a detonation can or some sort of microphone.

ive been trying to get simon to do this on his van to adjust his timing.

you can record the sound and analyze it to determine the frequency then a bandpass filter can be constructed to interface the wide range sensor to more simple electronics. i think audacity can do fast fourier transforms to show frequency peaks.

ive been working on a knock box to compare the knock output of narrow range sensors (or wide range ones with a bandpass filter) to a preset curve with respect to RPM but since its summer the project has dropped off some cause im outside more. its completely tunable and datalogs knock voltage and RPM. hopefully i get trapped in the house some to work on it.

i just wish i had cyl by cyl timing control so that i could make each cyl knock independently via timing (in a safe manner... low or no boost) so that i could determine the best place to put a knock sensor so that the signal strength is the same from each cylinder. thats why the 8v motors have the sensor on the intake. it gave the most even signal from each cyl knock event. same with the location on the TIII motor. with the SRT motor, they have a specific table in the code that tells the knock threshold voltage per cylinder because the sensor doesnt "hear" equally from each cylinder. the voltage values in those tables are the same for cyl's 2 and 3 but less for cyl's 1 and 4.

Brian

[Austrian Dodge]

so you put the vw sensor at the stock knock sensor place?

piece of art, did i tell you that before?

[turboshad]

i had a feeling that you were going to say something about listening to knock via a detonation can or some sort of microphone.

ive been trying to get simon to do this on his van to adjust his timing.

you can record the sound and analyze it to determine the frequency then a bandpass filter can be constructed to interface the wide range sensor to more simple electronics. i think audacity can do fast fourier transforms to show frequency peaks.

ive been working on a knock box to compare the knock output of narrow range sensors (or wide range ones with a bandpass filter) to a preset curve with respect to RPM but since its summer the project has dropped off some cause im outside more. its completely tunable and datalogs knock voltage and RPM. hopefully i get trapped in the house some to work on it.

i just wish i had cyl by cyl timing control so that i could make each cyl knock independently via timing (in a safe manner... low or no boost) so that i could determine the best place to put a knock sensor so that the signal strength is the same from each cylinder. thats why the 8v motors have the sensor on the intake. it gave the most even signal from each cyl knock event. same with the location on the TIII motor. with the SRT motor, they have a specific table in the code that tells the knock threshold voltage per cylinder because the sensor doesnt "hear" equally from each cylinder. the voltage values in those tables are the same for cyl's 2 and 3 but less for cyl's 1 and 4.

Brian

Mmmmmmmmmm.............fast fourier transforms. There's something I thought I would never have to get into again. That sounds like a really interesting project. Please keep me updated if you get further on it. Even if you had the sensor in the intake, wouldn't you still need different knock event voltage look ups since the furthest cylinders will always have a smaller voltage?

so you put the vw sensor at the stock knock sensor place?

piece of art, did i tell you that before?

I'm pretty sure the boss I mounted my sensor to is the stock location but I can't remeber for sure. It was just one I had available in the center of the engine.


I put a bit of time in last night to start tuning the boost. I kept getting knock right at the 5000 RPM point and I now have my timing backed down to 9 deg at that point with ~20 psi. Besides our crappy 91 premium fuel I think I am going to have to do something to get any higher on pump. I can get 94 ethanol blended but only one brand of gas station carries it and I don't want to be tuned for just one station.

I also am noticing that this year I am having to run much higher duty cycles on my EBC to get the same amount of boost I had last year. I am also seeing more vaccuum at idle, like in the 24 in/hg range. The only change would have been the 2.4l intake cam. Does it make sense that with the bit of inherant extra overlap that I would see more idle vaccuum and less boost? Should I even bother trying to mess witht he gears or should I just fix the dowel on the 2.0l cam and put that back in? I'm really not completely sure where I should go as I don't have a lot of exprience with cams (read "no experience")

Please comment as I'm curious to what others think.

[t3rse]

Brian, run an undersized injector in a single cylinder to induce knock.

DJ, yes you mounted the sensor in the stock location.

[Aries_Turbo]

i like the idea of setting up timing using the "listening" method and it works great. i just like some electronic means to keep an eye on things during regular use of a vehicle. a nanny if you will to keep an eye out for bad gas, high temps etc.

using the intake, the factory guys found that they had a pretty uniform signal from all cylinders on the 8v setup. same with the TIII. they would just throw sensors all over the engine and see which locations worked the best as they made each cyl knock.

yeah ill keep you posted on the project. since im not a mcu code guy, i had frank do the code for the knock box and it works just fine so far but to have 4 different tables with 4 different values and have the knock box keep track of which cyl was which might be a little much for the MCU (arduino/atmel) and/or franks programming skills. 2 tables might be do-able and would allow for the use of the factory 2.4L/2.0L knock sensor mount or a centrally mounted location on any inline 4 cyl.

the issue with doing multi tables means that the code would have to be changed to use a timer/interrupt scheme with a cyl #1 pulse to determine rpm and individual cyl where as now it just uses a frequency to voltage converter to determine RPM. then again, i could still use that for RPM and determine cyl separately. that might work. when frank gets back from his honeymoon, ill have to see how hard that would be to implement into the code.

Berry, yeah i know i could reduce fuel to the cylinder to create knock in that cylinder but i dont want to have to do it that way. 1. its a hassle, 2. i could melt things and 3. timing would allow alot of testing with similar conditions without my results being faulty. i just have to see if Rob could do some code trickery in the factory code to allow that adjustment.

Brian

[omni_840]

Thanks for posting this up! I enjoyed it just as much this go around than the first time

[turbokid]

Wow thats a gorgeous car and a fantastic build.
Who says this isnt modern technology =)

[turboshad]

Well I threw the 2.0 intake cam back in and it made a very good improvement on what I could tune. I am back up to where I felt I should be with timing and the top end is much nicer. I'm off to pick up some fuel today to get a tune down for higher octane. Then it's off to the track tomorrow to see what the car, or most likely the driver, can do. I'm not expecting anything real spectacular since it is my first time racing in 3 years, the first time on slicks, and the first outing for the car. But you gotta get out to start some where.

DJ

[rx2mazda]

Anyone who has seen this car in person knows that these pictures do it no justice. IMHO, it is the best looking street driven modded P-body there is! Attention to details is amazing

Now get to the track and give us some numbers!

[AzShadow]

This car is absolutely nuts! good luck at the track