Hello All,
I'm interested in converting my stock D-Jet 2.0 to SDS. What parts of the D-Jet can I retain, and what parts will I have to buy new in addition to the SDS system. I'm trying to take small steps to make it affordable, so I'm trying to retain as much of the stock system as possible.
Also, I've read about how easy it is to tune, what do you tune it to? Basically, what are target AF ratios you are looking for at each RPM range? Thanks.
Full Version: D-Jet conversion to SDS
The air cleaner, TB, plenum, rails, injectors, pump and reg all stay. The djet dizzy can be used.
You need the SDS, 1-bar map, TPS (counter clock-wise I believe, the one with the grey center), the head temp sender (unless yours is almost new...it's the same as stock) and get the pump relay option. The rest of the senders come with the base system.
If you mount it in the engine bay or rear trunk you will need an extra DB-9 cable, but any Staples or computer store will have that.
You will also need a wide band meter, get the SDS one then you have plug and play data-logging.
You need the SDS, 1-bar map, TPS (counter clock-wise I believe, the one with the grey center), the head temp sender (unless yours is almost new...it's the same as stock) and get the pump relay option. The rest of the senders come with the base system.
If you mount it in the engine bay or rear trunk you will need an extra DB-9 cable, but any Staples or computer store will have that.
You will also need a wide band meter, get the SDS one then you have plug and play data-logging.
Darn it Mark, you beat me to it.... on the road and working late, I didn't get a chance to follow up on this one...
interesting reading can be found here:
http://www.914world.com/bbs2/index.php?show...c=53733&hl=
I am still tuneing, as often as I get home, but the base tune would start and drive the car. If you are using the factory intake/fuel system, your tune may be easier still, as you will probably have a more stable vaccume signal, and more linear airflow. Boy, when those ITB's open up, you need to dump in the fuel to keep up.
If you are going with fuel only, retain the stock dizzy or upgrade (eventually) to a Mallory. I've never used one myself, but if others on the board swear by then, rather than at them, they must be good. I had strongly considered going this route, but decided to jump in the deep end rather than splash around the shore.
If you are going a little more all out, and getting the crank fired ignition, get ready to drop the motor and fabricate a little. It really wasn't all that hard. I'm not sure, but quite certain, that if you get the fuel only system, you can't just add the coil pac and upgrade to the crank fired ignition at a later date- I think you have to upgrade the whole ECU, but Mark would know for sure on that.
Absolutely budget $$$ for the WMS wideband system. It integrates with the SDS and makes the tuneing SO much smoother. Just read the SDS website, and down load the manuals. Read them often. The more you read, the more you know, the more familier you get with the system, the less scary it becomes.
-Would I do it again? For sure, the education along the way has been great, and I find the work/puttering around relaxing.
-Was it plug and play? C'mon, is anything really that easy? But this was close.
-Is the car faster? Don't know just yet. My combo of ITB intake/crank fire ignition/"euro" longblock/stock cam/SDS is, I think, the first of its kind. Jake may have done some combos that are similar, but he ain't talkin... When the dyno is done, results will be posted. When that will be is anyones guess.-
interesting reading can be found here:
http://www.914world.com/bbs2/index.php?show...c=53733&hl=
I am still tuneing, as often as I get home, but the base tune would start and drive the car. If you are using the factory intake/fuel system, your tune may be easier still, as you will probably have a more stable vaccume signal, and more linear airflow. Boy, when those ITB's open up, you need to dump in the fuel to keep up.
If you are going with fuel only, retain the stock dizzy or upgrade (eventually) to a Mallory. I've never used one myself, but if others on the board swear by then, rather than at them, they must be good. I had strongly considered going this route, but decided to jump in the deep end rather than splash around the shore.
If you are going a little more all out, and getting the crank fired ignition, get ready to drop the motor and fabricate a little. It really wasn't all that hard. I'm not sure, but quite certain, that if you get the fuel only system, you can't just add the coil pac and upgrade to the crank fired ignition at a later date- I think you have to upgrade the whole ECU, but Mark would know for sure on that.
Absolutely budget $$$ for the WMS wideband system. It integrates with the SDS and makes the tuneing SO much smoother. Just read the SDS website, and down load the manuals. Read them often. The more you read, the more you know, the more familier you get with the system, the less scary it becomes.
-Would I do it again? For sure, the education along the way has been great, and I find the work/puttering around relaxing.
-Was it plug and play? C'mon, is anything really that easy? But this was close.
-Is the car faster? Don't know just yet. My combo of ITB intake/crank fire ignition/"euro" longblock/stock cam/SDS is, I think, the first of its kind. Jake may have done some combos that are similar, but he ain't talkin... When the dyno is done, results will be posted. When that will be is anyones guess.-
QUOTE(Mark Henry @ Sep 5 2006, 06:00 PM) 
The air cleaner, TB, plenum, rails, injectors, pump and reg all stay. The djet dizzy can be used.
You need the SDS, 1-bar map, TPS (counter clock-wise I believe, the one with the grey center), the head temp sender (unless yours is almost new...it's the same as stock) and get the pump relay option. The rest of the senders come with the base system.
If you mount it in the engine bay or rear trunk you will need an extra DB-9 cable, but any Staples or computer store will have that.
You will also need a wide band meter, get the SDS one then you have plug and play data-logging.
how did you tune it, and what was your target data when you were tuning?
how did you tune it, and what was your target data when you were tuning?
[/quote]
Read the SDS website, download the manual. Briefly, when using the WMS wideband, the SDS controller will display your AFR (air/fuel ratio) numerically, that is, 12.7:1, 15.3:1, or whatever it happens to be. When using other 02 systems, you may have displayed on the controller the O2 sensor voltage, which you then need convert to a ratio, or you just need to KNOW what voltage = what ratio. The SDS controller will display the following: rpm/fuel amount/02 reading, such as: 3250/115/15.7, where 3250 is the rpm point you are viewing/adjusting, 115 is the fuel value, and 15.7 is your air to fuel ratio. Now do the math. Lets say you want 13.5 AFR at this rpm point. 15.7/13.5 = 1.16. You need to increase your fuel at this rpm point by 1.16% to get the AFR you want. So.... 1.16 x 115 = 133. Change your fuel value at 3250 from 115 to 133, and you should have your lower AFR at this rpm point. Its not all that hard.
[quote name='ottox914' date='Sep 5 2006, 08:29 PM' post='764923']
how did you tune it, and what was your target data when you were tuning?
[/quote]
Read the SDS website, download the manual. Briefly, when using the WMS wideband, the SDS controller will display your AFR (air/fuel ratio) numerically, that is, 12.7:1, 15.3:1, or whatever it happens to be. When using other 02 systems, you may have displayed on the controller the O2 sensor voltage, which you then need convert to a ratio, or you just need to KNOW what voltage = what ratio. The SDS controller will display the following: rpm/fuel amount/02 reading, such as: 3250/115/15.7, where 3250 is the rpm point you are viewing/adjusting, 115 is the fuel value, and 15.7 is your air to fuel ratio. Now do the math. Lets say you want 13.5 AFR at this rpm point. 15.7/13.5 = 1.16. You need to increase your fuel at this rpm point by 1.16% to get the AFR you want. So.... 1.16 x 115 = 133. Change your fuel value at 3250 from 115 to 133, and you should have your lower AFR at this rpm point. Its not all that hard.
[/quote]
...that is the crux of my question how do I know if I need 13.5 at 3250, or 15 at 4000 etc.?
how did you tune it, and what was your target data when you were tuning?
[/quote]
Read the SDS website, download the manual. Briefly, when using the WMS wideband, the SDS controller will display your AFR (air/fuel ratio) numerically, that is, 12.7:1, 15.3:1, or whatever it happens to be. When using other 02 systems, you may have displayed on the controller the O2 sensor voltage, which you then need convert to a ratio, or you just need to KNOW what voltage = what ratio. The SDS controller will display the following: rpm/fuel amount/02 reading, such as: 3250/115/15.7, where 3250 is the rpm point you are viewing/adjusting, 115 is the fuel value, and 15.7 is your air to fuel ratio. Now do the math. Lets say you want 13.5 AFR at this rpm point. 15.7/13.5 = 1.16. You need to increase your fuel at this rpm point by 1.16% to get the AFR you want. So.... 1.16 x 115 = 133. Change your fuel value at 3250 from 115 to 133, and you should have your lower AFR at this rpm point. Its not all that hard.
[/quote]
...that is the crux of my question how do I know if I need 13.5 at 3250, or 15 at 4000 etc.?
You need some books/info on basic engine operations. Generally, and I'm sure I'll be corrected if someone thinks otherwise, AFR's of 12.5:1 are considered best for overall HP and TQ, with MPG and emissions ignored. Your MPG will be less than stock, and emissions worse. 14.7:1 is the "perfect" mixture for maximun burn of the fuel you use. Mixtures leaner than that, say in the 15-16-17:1 range will produce better mileage, at the expense of performance, and the leaner you get, the greater risk of detonation and blowing a hole in a piston.
And. Different engines like different ratios. Our air cooled, 8 valve heads might like a richer mixture at idle than a more modern, water cooled, 16 valve head. Your engine compression ratio will make a difference. There are lots of variables that will determine what works best for YOUR engine. If you have a turbo, you may want to be richer than 12.5 at wide open throttle, but being that rich on the highway might be way to rich... thats why its called tuneing.
And. Different engines like different ratios. Our air cooled, 8 valve heads might like a richer mixture at idle than a more modern, water cooled, 16 valve head. Your engine compression ratio will make a difference. There are lots of variables that will determine what works best for YOUR engine. If you have a turbo, you may want to be richer than 12.5 at wide open throttle, but being that rich on the highway might be way to rich... thats why its called tuneing.
I continually find the best power, EGT and efficency @ 13;1 AFR WOT.
At cruise i continually find the best MPG, EGT and cleanest running at 13-5-14:1
12.5:1 has never made more power for us, some Nickies engines make their peak power at 13.5:1 and can cruise all day at 15;1
At cruise i continually find the best MPG, EGT and cleanest running at 13-5-14:1
12.5:1 has never made more power for us, some Nickies engines make their peak power at 13.5:1 and can cruise all day at 15;1
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