COP 4 cylinder - 924s/944 & other content - Very Long Po

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Dean924s
Posts: 228
Joined: Fri Nov 07, 2008 2:57 am
Location: USA - MA

Post by Dean924s »

Ohya a site note here. A set of wires for a 1994 Mustanng with a 3.8 V6 would apear to be the set I need. Yes I will wast wo wires but the Escort wires are just to short for my application. If ther eis no cost / minimal cost difference for a V8 set I may considder it as I can then get two sets for the price of one :D
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Dean

Dean924s
Posts: 228
Joined: Fri Nov 07, 2008 2:57 am
Location: USA - MA

Post by Dean924s »

Here is a clip of my most recent map. It drives really well
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924s fast 93 corected.jpg
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Dean

Dean924s
Posts: 228
Joined: Fri Nov 07, 2008 2:57 am
Location: USA - MA

Post by Dean924s »

============== Moved from first page ==============
EDIT 2009-1-18 - This EDIT List is a work in progress. This note will be removed when I finish this list of parts until them consider this a work in progress.

This section is for those that don't want to read my whole the whole story. Although I would hope that you would find it amusing, I understand that many will want just the list with instructions/comments that are relevant to getting there car converted and up and running.

To start out with I am basing this build on my car. It is a 1987 Porsche 924s (same as a 944 just different sheet metal) My motor is from a 1983 944. It is an 8V SOHC 2.5L water cooled 4 cylinder motor. There are some small differences between the pre and post 85.5 motors/cars. As I get to them in this writeup I will try note them.

The parts list:
I will brake this in to a couple sections. It is easier to select all the parts. Use it as a checklist if you want.

==
Trigger wheel:
http://www.mcmaster.com/
Part Number: 6325K67
Steel Plain Bore 14-1/2 Deg Spur Gear 24 Pitch
72 Teeth
3" Pitch Diameter
1/2" Bore
Catalog page 1039
In stock at $38.08 Each plus shipping
*Modification: Removal of two teeth 180 deg out from each other so you end up with a 72-2 trigger wheel

==
VR Sensor:

I used one from a 1986-1991 Mazda RX7's. It is part of the unit that is called a as part of the crank position sensor. Each unit has two sensors in it you only need one. Finding one new is not a easy and they are expensive new as you have to purchase the entire unit with the housing. Here is a listing for a new one >> http://www.drivewire.com/products/mazda ... nsor/8602/ Yes Big $$$ My suggestion is to search ebay and your local junk yards. Should be less then $20 for the pair of sensors if you remove them from the housing.
==
Mount for VR sensor

Front cover for the timing belt cam gear. Ebay or junk yard.
* Modification includes cutting out the center opening to 3.25" and drilling holes in it for the VR sensor mounting plate.

Piece of steel 1"x6"x1/8" - VR sensor mounting plate.
2 machine screws approximately 1.5 inches long
2 machine screws approximately 3/8" long all are 1/4-20 thread
10 washers (for shims)
4 lock washers
4 1/4 2- nuts
loctite - blue (semi permanent)

==
Ignition: I used all the parts from a 1993 ford escort that has the 1.9l motor. They key here is to decide if you are going new or used. What I would do is go to the local pick and pull and get the wiring harness pieces first. If you can get the coil and the EDIS unit as well great. If you can not get these or you want to get the EDIS and the Coil as new parts you will know what car to get them for (the ones you got the wiring from so the plugs match up)

- Wiring harness & plugs.
You can get a harness form the dealer but I am sure that is going to cost big $$$.
I strongly recommend that you get this from the junkyard.
Inspect the plugs you get and make sure that they are not cracked or otherwise damaged.
Get a much of the wiring as you can. At a minimum get 12 inches of wire on each plug. 18" is better. 24" will make your life much easier down the road.
If there is a resistor with the coil pack on the car you are getting this from I recommend taking it with you as part of the wiring harness.
Write down the Year make and model you get this from you will want it for later.

- Coil Pack and the mounting bracket:
Mounting bracket:
Get used from junk yard. <Very important to get this>
Also make sure that you get the small bolts that mount the coil to the bracket.
Coil pack:
New or used it does not matter.
Used they are $20 (going rate from local pick and pull)
New they are Still cheep at $47.00 at Autozone
http://www.autozone.com/R,1613004/vehic ... Detail.htm
Get the resistor if it has one attached. If you listen to the radio you will thank me.

- EDIS module and mounting bracket:
Again new or used it is your choice.
New >> http://www.autozone.com/R,1329810/vehic ... Detail.htm
A tad pricey at $120.
Used: I got it free as part of the pile of wiring and the coil packs I got from the pick and pull yard.
I would expect to pay between $10-$20 used. They are also on eBay

- Misc Wiring
Go to the local parts store or electrical supply store and get some.
Several different colors will be very helpful.
I keep 6-8 rolls over my bench in my
shop on a dowel. A bit of an investment but very worth it. I pay around $7 a roll for 100 feet I think
Make sure that you get multi strand copper wire that is rated for automotive
use (temp, oil and abrasion resistant insulation) Most standard wires you get
are fine but ask when purchasing. The Internet is a good place to get this as well.

- Shielded Cable
I found that Radio Shack has a very nice 24 ga shielded cable for less than $10 for a 50 foot roll.
You could also use a piece of USB cable but it has 5 wires and I am not sure if it will stand up to the temps in the engine compartment.

-- Plug Wires
I found that those for a 1994 Mustang with a 3.8l worked just fine. you end up with two extra wires.

- Plugs. Get a set of rezistor plugs that corospond to the oens that you were using. Again I found that those from a 1994 Mustnag with a 3.8L worked just fine. I am sure that NGK has a rezistor verson of the stock 944 plug that would work as well. I stuck with the Ford plug as it matched the ignition system. Non rezistor plugs feel liek you have added a deg or three of timing. I am also playing around with gaps as I am not sure if I should use the escourt plug gap (the EDIS unit and coils are from that car) , the ford Mustang 3.8L gap (as I am using those plugs) or if I should use the porsche plug gap. (This is a porsche motor)

To be continued
Last edited by Dean924s on Mon Jun 07, 2010 2:54 am, edited 1 time in total.
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Dean

Dean924s
Posts: 228
Joined: Fri Nov 07, 2008 2:57 am
Location: USA - MA

Post by Dean924s »

Made some changes to the installation.

They are:

New trigger wheel that is both wider (was 1/4" now it is 3/8") and larger diameter I fabricated it from a Martin Spur Gear #S2072. This resulting change also made the teeth bigger.

New sensor mounting directly to the cam cover. I also modified the sensor by reversing how the magnet is mounted. This resulted in the magnet being moved away from the trigger wheel allowing for the larger trigger wheel diameter to be used.

I also glued the inductive pickup to the steel center preventing it from vibrating and moving as the other could. With the new configuration of the of the sensor the inductive pickup could actually slide down and hit the trigger wheel.

I also found loose crimp connections where the VR sensor connected to the harness. I am sure was not helping things. The end result is a much better running car. Pulls much better than before. This is how Porsche should have tuned from the factory!!

Video of it running >>>> http://www.youtube.com/watch?v=-sDNVjqg4cM

Pix of the new installation
Attachments
2009-2-28 NEW-TRIGGER-WHEEL 006.jpg
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2009-2-28 NEW-TRIGGER-WHEEL 010.jpg
2009-2-28 NEW-TRIGGER-WHEEL 010.jpg (166.07 KiB) Viewed 63176 times
2009-2-28 NEW-TRIGGER-WHEEL 008.jpg
2009-2-28 NEW-TRIGGER-WHEEL 008.jpg (113.77 KiB) Viewed 63178 times
Last edited by Dean924s on Mon Sep 07, 2009 2:31 pm, edited 1 time in total.
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Dean

Dean924s
Posts: 228
Joined: Fri Nov 07, 2008 2:57 am
Location: USA - MA

Post by Dean924s »

And the new map that goes with the new and improved set up.

I can not tell you all just how well this is now running. My car never ran this well. Even with the the stock ignition and a fresh tuneup new wires and a cap and rotor it was never this good. It is amazing the difference. I can only imagine what it would be like running with crank fired instead of the cam fired as I am. I am sure that I am loosing a little resolution due to belt stretch and what not but it is such a vast improvement over the old cap and rotor.

This really proves that wiring and connections are key to making this work. I am not sure that the whole issue with the loose connection on the VR sensor wires I found was probably the whole problem. But now that I have the larger trigger wheel I am sure that I am getting a much cleaner signal to the MJLJ

You will note that the map has changed quite a bit. I worked on it timing 30-70 runs on my favorite section of highway. I also re worked the bottom end of the RPM scale to smooth out the jerkiness of the off idle feel that you have. I also found that the Idle will surge if the Timing is to high. It hunts between 100 ad 1500 rpm. By lowering the timing in this area back to close to the stock settings the car changes completely. Around town end in traffic it is a mild mannered normal car. but once off idle it makes this transformation from an old tired 944 to the feel of a modern car. The car now pulls smooth of the line and accelerates smoothly like a rocket gathering speed. Once over 1500 rpm it just goes. I have put the redline at 5250 as things just get silly fast over 5000.

Anyway this seems to be a really good tune. Until I can get to the Dyno for some tuning this will probably be the map for now. I think I am going to put the knock sensor in and do some testing and see where it actually starts to knock. I should probably do this with a tank or two of 87 octane as well.
Attachments
924s 93 octain map.jpg
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Dean

Dean924s
Posts: 228
Joined: Fri Nov 07, 2008 2:57 am
Location: USA - MA

Post by Dean924s »

This is the map I think I am going to try on the dyno and or with the knock sensor and a headset on.
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Going to try this on on the dyno.jpg
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Dean

Dean924s
Posts: 228
Joined: Fri Nov 07, 2008 2:57 am
Location: USA - MA

Post by Dean924s »

Things are getting out of control here. :shock: But it is so much fun :D
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MJLJ GETTING OUT OF CONTROL.jpg
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brentp
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Post by brentp »

You're outta control! If we had a marketing position open you'd be our first call. :)

Are you going to do a before and after (i.e. distributor vs. Megajolt) on the dyno for comparison?
Brent Picasso
CEO and Founder, Autosport Labs
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alexander
Posts: 246
Joined: Sat Jan 19, 2008 4:33 am
Location: sydney, australia.

Post by alexander »

dean, dont forget about a cover for that trigger wheel. it is in a very exposed position and would do very bad things to a stray finger.

alexander.

Dean924s
Posts: 228
Joined: Fri Nov 07, 2008 2:57 am
Location: USA - MA

Post by Dean924s »

brentp wrote:You're outta control! If we had a marketing position open you'd be our first call. :)

Are you going to do a before and after (i.e. distributor vs. Megajolt) on the dyno for comparison?
Yes I still intend to do this as it is only a 5 minute swap over back to the Bosch cap and rotor. I have kept all the wiring in the car as well as the stock coil as there has been no real reason to remove it (and it is winter and snow and cold out). Ok I am a wimp but at the moment I don't have an indoor place to work on cars.

This would be a hell of a marketing tool. If I got a true 10 percent gain of HP and torque the NA 944 guides would be beating a path to your door Brent. The only thing I am trying to work out is if I can get it to be truly crank fired and I think I found a source for the trigger wheels.
>> http://www.goingsuperfast.com/Trigger-wheels.html <<

I am going to give them a call as I am not sure what sensor that they would use as the wheel is very thin but it looks to be a bolt on deal to the crank. This would make me very happy! Logic sais that if they are manufacturing this piece then they must know how to mount a sensor down there. I am hoping it is a stock ford unit that I already have. I have spoken with another 944 guy and he used the stock VR sensor from the 944 but those are dam expensive compaired to the ford units. On of the big reasons for doing this has been to ultimatly get away from the stock speed and refrence VR sensors that the car uses in favor of cheaper and more reliable OE ford units.
Last edited by Dean924s on Mon Sep 07, 2009 2:35 pm, edited 1 time in total.
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Dean

Dean924s
Posts: 228
Joined: Fri Nov 07, 2008 2:57 am
Location: USA - MA

Post by Dean924s »

alexander wrote:dean, dont forget about a cover for that trigger wheel. it is in a very exposed position and would do very bad things to a stray finger.

alexander.
I am actually working on this now that I got it running correctly However I may toss it all to the curb and go true crank fired if the wheel I found above is viable. Then I will just put a plate over the hole where the cap and rotor was.
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Dean

Redbird
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Joined: Thu Jun 19, 2008 7:47 pm
Location: Wynantskill, NY

Post by Redbird »

Do you have a source for that Martin gear you used? Looked around and cant seem to find a distributor for them. I'm thinking about going the 72 tooth route as the more the engine comes together the less room I seem to have to mount things and i have a spare distributor just laying around.

Dean924s
Posts: 228
Joined: Fri Nov 07, 2008 2:57 am
Location: USA - MA

Post by Dean924s »

Redbird wrote:Do you have a source for that Martin gear you used? Looked around and cant seem to find a distributor for them. I'm thinking about going the 72 tooth route as the more the engine comes together the less room I seem to have to mount things and i have a spare distributor just laying around.

My original gear (1/4" wide) I got through McMaster Carr on line:
http://www.mcmaster.com/
Part Number: 6325K67
Steel Plain Bore 14-1/2 Deg Spur Gear 24 Pitch
72 Teeth
3" Pitch Diameter
1/2" Bore
Catalog page 1039

I still think that this may have been ok since when I changed over to the 3/8" wide one I found a loose connection in the VR sensor wiring. However I am now using a 3/8" wide wheel that is a bit larger in diameter and I had to remove the hub from it to bring it closer to the face of the cam gear cover so the sensor would line up properly and allow for a good solid mounting of the sensor directly to the cover.


Anyway to get the new gears I went to the martin website (google is your friend) and looked at there catalog and found what I wanted. I then called them directly and they steared me to there local branch (listed below) Craig smith was very helpful!! However you can not purchased directly form them you will have to go through a retailer. Craig was very helpful in finding a local company that I could purchase from. I called them and placed the order and they shipped it to my door. I would bet that there is one local to you as there was with me.

Here is the info I have for my local sources.

Craig Smith
Martin Sprocket and Gear
357 Fortune Blvd.
Milford, Ma 01757
Phone: 1-508-634-3990
Fax: 1-508-634-3998
e-mail: <mailto:[email protected]>:
Web: www.martinsprocket.com

The local retailer is:

MOTION INDUSTRIES INC
11 CABOT ROAD
WOBURN, MA 01801
Phone: 7813765850
Fax: 7813765908


The details for the second gear that I ordered that was 3/8" thick/wide was are as follows

1.0 MARTIN S2072 14 3/8 SPUR GEAR
1-2 DAYS/UPS
Item No..........: 00372887
Last edited by Dean924s on Mon Sep 07, 2009 2:38 pm, edited 1 time in total.
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Dean

Dean924s
Posts: 228
Joined: Fri Nov 07, 2008 2:57 am
Location: USA - MA

Post by Dean924s »

I just thought I would update this and say that I drive my 924s just about every day. It sees 200-500 miles a week and the MJLJ-V4 has been flawless. Not a hiccup no issues. Once you get it up and running and get the tune proper it is basically like a hammer. The no start condition I was experiencing with the stock system has not occurred since I installed he MJLJ.

This is one of the primary reasons I have not been posting much is there has been nothing to post about. I put key in turn car on and drive. No issues!!!!

For anyone that is worried about reliability of these units don't be. What I can say is that you have to make a bullet proof installation. Make all connections very tight and double check everything. Wires hanging loose will result in loose connections or something that was in shorts. Cover everything in plastic shielding. Secure things with lock washers and or locktight. Since I have a background in Sports car racing and years ago I dabbled in NASCAR I tend to try to build to standard that I think will survive the track. Over engineering is a good thing! A side benefit to this is that you will usually end up with a neater installation.

When all else fails think like the Rotisserie oven infomercial. You want to "set it and forget it" :D
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Dean

Dean924s
Posts: 228
Joined: Fri Nov 07, 2008 2:57 am
Location: USA - MA

Post by Dean924s »

Another update. WITH NOTHING TO REPORT!!! I drive this car practically every day and it is rock solid. I am just hoping that Brent will see the need to take a leap into the world of EFI. hint hint hint LOL.

Anyway for anyone that is considering this. JUST DO IT!!!! It has been one of the best upgrades to my car.
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Dean

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