Ajustable CPS?

Has anyone though about taking a CPS and enlarging the holes some to make is somewhat adjustable? How much of a difference would you be able to make would you think? I would doubt that you would be able to get more than a couple degrees but it might be possible to get enough of a difference to make a power difference.

What do you guys think?

PFunk242 said:

Has anyone though about taking a CPS and enlarging the holes some to make is somewhat adjustable? How much of a difference would you be able to make would you think? I would doubt that you would be able to get more than a couple degrees but it might be possible to get enough of a difference to make a power difference.

What do you guys think?

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If you want a trick that makes a differance, why not build an adjustable map sensor. That changes the timing and fuel and can be set from a dial on your dash.
http://www.angelfire.com/my/fan/MAP_adjuster.html

Hi,
This site is just what you're after http://www.rightcoastcrawler.com/billaVista/CPS_mod/CPS.htm

Jeepcreep

Thanks guys. Ok so it has been done. But how much of an effect wouild it have do you guys think? I want to get some more low end grunt out the the 4.0 by advancing the timing some. Does anyone think I'll even be able to tell a diffrence at all??

Does it still die on left turns?

Search For Spark Translator On Street And Performance Forum I Had A Post About This Issue And There Is A Box You Can Add To Advance Or Retard Timing

langer1 said:

Does it still die on left turns?

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It does on Right turns. I got a new CPS for it today hopefully that will fix the problem. I have been so bussy i haven't had much of a chance to work on it lately.

Thanks for the info markaboo929 i will check that out.

That is how my RENIX acted at first, the dying on right turns was the signature symptom, then progressively got worse...hard starts, dying on bumps, cutting out on accelleration, all intermittently.

Check your Knock Sensor, mine was broken internally then finally fell apart exposing the problem. The RENIX has NEVER run better!!

Cory

Mine is a 92 so i don't have a Knock sensor but thanks for the heads up on that.

PFunk242 said:

Mine is a 92 so i don't have a Knock sensor but thanks for the heads up on that.

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Are you sure about that, I'm not?

langer1 said:

Are you sure about that, I'm not?

Click to expand...

A 1992 XJ uses the Chrysler ECU and does not have a knock sensor.

Markaboo929,

Your posts on the Spark Translator are interesting. I went to the website you recommended and tried to get more info, but for some reason couldn't. Since you are using a spark translator, I have a few questions for you:

1. Is the Spark Translator adjustable or not?
2. Can it be switched off and allow you to go to standard ignition?
3. What was your timing at idle without the Spark Translator?
4. What was your timing at idle with the Spark Translator?
5. If you crank in more timing at idle, say 10 more degrees, does the Spark Translator still limit the total advance timing at WOT to say 35-37 degrees?
6. How did you wire-in the Spark Translator to your Renix system?
7. Can the Spark Translator be adjusted while you're driving?

Thanks in advance.

Best regards,

CJR

did u find it on the web site?i did not check timing before or after at idle or at rpm's.you can wire in a switch to change between the box and stock settings-i did not-4 wires to hook up 1-to ground 2-to power 12 v 3-one from the ecm to spark control to ignition module 4-the other end of the spark control wire-it will go in line for the spark control wire to the ign module.it is adjustable inside the unit with dials that have #s on them i found the numbers may not be * degrees of advance for the inline the box is for gm v8s and v6s.it is adjustable as u drive that is how i tuned mine in.put it this way i have full control of spark advancing or retarding.it can go from backfiring to pinging and anything in between.while driving u can adjust it and have instant results.i feel it has made a difference of cource i use premium fuel to benifit from the added timing advance.i have to look at my settings on the box to let u know if u want i played around til i found a good setting.i mounted mine next to ecm under the dash-i have a renix system ecm under dash.so yuors maybe differnent if ecm under the hood this set up will only work on renix with ignition module 87-90. for 91 up that same company has a box for the crank sensor to work on v8s-same idea as the 1 for the ign module just for the crank sensor-it MAY work on 91 up crysler controlled pcm .dont know that 1. hope this answers some of your questions.let me know if u need more info or help.

oh yeah it adds or retards spark to what the stock out put is-not to a fixxed number and thats it.go to the web site and type in spark translator in the search box-to look at the 1 for crank sensor type in crank sensor that should do it

Markaboo929,

Thanks for responding to my questions. I revisited that website again(www.fuelsystemparts.com), opened everything up and found a lack of detailed information on that spark translator. Your reply was more informative. Thanks again. It seems that spending $30 to $50 for a high altitude CPS or just modifying the mounting bracket of a standard CPS to give more advance is a lot less expensive than spending $180 for the spark translator. However, the adjustment of the spark translator "on the fly" is a worthwhile feature that would speed things up in getting to the maximum advance setting. I would suspect these spark translators are not that complex a design to build. Maybe some EE will tell us how to fab one like the adjustable MAP gadget. Hope springs eternal!

Best regards,

CJR

I don't think you would not get much if any improvement on a stock engine.

Don't forget the CPS in also timing for your injectors. Now they turn on at the start of the intake stroke, turning them on any sooner would waste fuel and cause the CAT temp to rise.
The O2 sensor would lean the mixture and you would really be lean because some of your fuel is going just laying in the intake..

i thought about that one too.i even went ahead and contacted a company about making what i wanted to find out that it wouuld be VERY expensive to make a prototype for an adjustable spark unit-that led me to the company that had that spark uint(translator) as they put it.in side the unit it has a circuit board and some small dial type pentiometers in it.i may some day take it apart and list what parts are used and how they go together and "de-code" it to find what the pieces actualy cost and go from there.there probably is some programming into it there is a chip inside there too.a nother person had posted a reply and had a good point it may also shift the injector timing may be dont know but fwiw the box only changes actual spark timing and does not mess with injector timing as stated.yes $180 seems expensive and when i wanted to try one that price was hard for a desiding fact but it did the job and does indeed advance or retard the timing on the 4.0 do i like it ....yes i now have a 03 grand rokee motor going in my 88 and am using the tps that came with my motor i know there is a write up aboput using the ho t body on the renix motor ...the reason....the ho tps does not go to the full ref volts-5.0v-as the renix one does it goes to 3.5 at full throttle ...but i experimented and found that if you increase the refernce volts to about 6.7volts by using a map adjuster to regulate the input volts like u would for the map sensor it does go from .70 or so up to the full 5.0 volts at wot like the renix one does sooo i am going that route and make another map adjuster and use it for my tps-which will give me full control of throttle response as well as-1-spark timing-2-air fuel ratio-3-and now throttle response making my set up fully adjustable . it will take some playing with to get it right but i do work at a gm dealer that has a dynojet dyno to use at my will anytime i want.i do corvette perfomance mods and chevy mods at the dealer so i like messing with my jeep obviously.i searched for an ecm that mopar used to have for the renix but stopped making one a while ago.untill now.......i have unlimited tuning possibilities.

no msd type spark units go between the coil wires to add muli capacitive spark discharge to the coil does only retard timing the spark unit i have is about the size of a ciggerette box and goes between the wire from the ecm to the ignition module to interupt the signal and adds timing.look at www.fuelsystemparts.com and search for spark translator that is what i have/use.