Hey guys. I own a 99 Sentra SE-L and I'm looking for some advice from other 98 & 99 Sentra SE owners.

First, has anyone installed a JWT ECU? I know that they don't make one, but I was told that with a few changes the 97 200SX SE-R ECU will work great.

Second, what exhaust systems are you guys running? Will a Greddy for a 200SX SE-R work? Are any modifications required? Does anyone have a Stromung? Any feedback would be great.

Thanks in advance for your help.

Jason
99SE-L

Yea, you can run a JWT ECU. When you order it, they'll give you the instructions on what to do to it.

I'm running a GReddy cat-back made for the '98-'99 cars. You have to be sure it's for the '98-'99 cars, though; our cats are a bit longer than the earlier cars.

Originally posted by nsracer
Yea, you can run a JWT ECU. When you order it, they'll give you the instructions on what to do to it.

I'm running a GReddy cat-back made for the '98-'99 cars. You have to be sure it's for the '98-'99 cars, though; our cats are a bit longer than the earlier cars.

what kind of intructions would that be??? i was given the advice of buying a g20 ecu first since it is only $100 bucks, then getting the JWT ecu with the s3/s4 program when i buy cams in the future or install the g20 ecu while i wait for JWT to return my ecu.

I have a 96 200sx Se-R ecu in my 99 SE-L you have to reroute a couple vaccum lines and well the check engine light comes on because the O2 sensor in the cat is different then the 95-97 200sx Se-Rs. The lame thing about this mod is the price I paid 800bucks for the whole procedure $595 for the JWT ECU and since my ecu was a 99 unit I couldnt use it as a core because allegedly they cant crack the code so I had to buy the core which was 200

As far as the exhaust goes at the time the only thing available for my 99 SE-L was the Greedy SP and Im not a fan of 6 inch tips so I opted to go with a custom done 2.25'' mandrel bent piping with a nice apexi N1 muffler w/silencer the tip is a sleeping sleeper 90mm I love it. Now there are a couple more manufacturers that make exhausts for our 98-99 SEs I do believe stromung is one of them and the rest I cant remember

Does any body know what vaccum lines need to be moved, and where to put them. I have 94 ecu, and get the check engine light.

The JWT ECU will run fine, un-modified in a 98-99 car. However you will just get a CEL light and your idle may hunt a bit. You have to do is unplug the sensor on the gas tank. Believe it or not and it sounds stupid but the amount of gas in your tank can effect your idle if you have a 98-99.

JWT got sick of taking 98-99 ECU's as cores or their stock of 95-97 ECU's became seriously diminished and now they won't take them.

BTW, a 95-97 exhaust needs to be shortened to fit. Mine works fine.

I have a 98 SE. The JWT ECU will work fine but for the money just get the G20 ECU unless you need a special program (VE/Turbo). 7500 rpm+no speed limiter. Check out www.car-parts.com. Exhaust. Skip the Strumung it is to small (2 inches) Find a good Magnaflow dealer and have one made with a 20 (or so) resonator and you pick the universal magnaflow rear muffler. All mandrel piping would cost around 300-450 for aluminum to stainless. Also, Nissan now seals a LSD that is Mechanical and fits in the non-lsd gearbox. Cost is $750 or so. I have the instructions for installing a JWT ECU to avoid the check engine light. I will be doing this over the next several weeks. You can ask me more then.

Steve

Thanks for all the feedback. But what year G20 ecu do I use? What is the redline & max. speed set at? Also, I've got JWT S3 cams. How does that change your suggestions? Can I go with a G20 ecu with the S3 cam program?

Thanks again.

Jason
99 SE-L

Originally posted by jasonsnicholson
Thanks for all the feedback. But what year G20 ecu do I use? What is the redline & max. speed set at? Also, I've got JWT S3 cams. How does that change your suggestions? Can I go with a G20 ecu with the S3 cam program?




OK.... where do I start.... the G20 ECU cannot receive the S3 cam program, and if it did, then it is no longer a G20 ECU, is it a JWT ECU and it will set you back $595+. When we say "G20 ECU" on this forum, we are referring to a STOCK, un-modified 1994-1996 ECU from an Infiniti G20. There are only 2 reasons for doing this swap, mainly the 7500 fuel cut, and no speed governor.

You will benefit even more with the G20 ECU since you have the S3 cams. The 7100rpms cut REALLY sucks with cams because you're losing out on all the top end power, the whole reason for having the cams in the first place.

Originally posted by 98sr20de
Also, Nissan now seals a LSD that is Mechanical and fits in the non-lsd gearbox. Cost is $750 or so.

I REALLY want more info on this. Do you know anybody that has it?

Originally posted by jacen99SE


I REALLY want more info on this. Do you know anybody that has it?

Ditto, I just found out about this 1 week ago. Nissan sells it thru the Nissmo devision. So you should be able to pick it up at a local dealer. It is a 1.5 way, mecanical differential designed for FWD cars. 38lbs breaking preasure. It does make some noise going into reverse and while turning very sharp corners. Similiar to a 4wd truck. Most to the time it would be quite. This is what the Nismo Manager told someone involved with se-r.net+Mike K. My thoughts are (interpretation of this info) that this thing should last better then the VSLD that is standard in se-r's because it is mechanical and probably not a suseptable to heat. Only, time will tell. If you are wondering what a 1.5 way LSD is read this. (http://www.kaazusa.com/answers.html#whatway) Cost is about $750. Part numbers for a non LSD tranny are 38420RS360, with LSD 38420RS365. Thats all I know. I don't know anyone who has tried this yet. Who will be the first to try this thing?

Steve

If I go with a JWT ecu for a 200sx SE-R the "check engine" light goes on because of the O2 sensor, right? Is there any way of fixing that problem? How about switching to a 200sx O2 sensor? Someone else posted that all I have to do is unplug the sensor on the gas tank. What side effects does that have?

Thanks

Jason
99 SE-L

Normally the EVAP canister collects gas fumes from the tank and filler and then releases them into the intake manifold. The 95-97 EVAP stuff is different than the 98-99, and you are disabling the part that purges the fumes into the intake manifold.
You can change the EGR solenoid to a 97 and switch some hoses around. I don't know if this step is absolutely necessary, but I did it.
You have to switch a couple wires at the ECU harness.

You can put a 97 O2 sensor in and the above stuff and not get a check engine light.

The O2 sensor for a 97 is a different size thread, and you'll have to get a sensor (around $100) and an adapter to fit the 97 sensor in a 98-99 cat hole (the 97 thread diameter is smaller). The rear O2 sensor doesn't do anything so nobody replaces it.

Also, you have JWT wire a resistor into the rear O2 sensor so that it is not needed. It works most of the time. To prevent a Check engine light just takes some work switching things around + the cost a a rear O2 sensor if you have a G20 ecu.

Steve

Yeah the guys at SR20Development told me that the O2 sensor in the cat for our cars (98-99SEs) is smaller than the 95-97 200sx SE-Rs so he said to buy an O2 sensor for the 95-97 and bore out the hole in the cat for the new O2 sensor. They said that O2 sensor just tells you that the cat is working properly

:rolleyes:

buy a 94-96 g20 ECU no matter what. You can use it now and If you decide to get the JWT program then send them the G20 ECU and they can program that, and you will save the core charge you would lose for not having a 97 and older ECU. I just put a 95 g20 ECU in my 99 G20 yesterday(same problems as 99 sel) . On my site (http://www.g20style.com/) I have the rewire (http://www.g20style.com/how_to_wire_a_95.htm) procedure staright from sr20development. I just got a 95 O2 sensor and I will probably do the rewire soon.

Originally posted by silverser99
Yeah the guys at SR20Development told me that the O2 sensor in the cat for our cars (98-99SEs) is smaller than the 95-97 200sx SE-Rs so he said to buy an O2 sensor for the 95-97 and bore out the hole in the cat for the new O2 sensor. They said that O2 sensor just tells you that the cat is working properly
actually the older O2 is smaller and you need to fill the hole. I have a 18mm sparkplug anti-fouler that I will adapt to acomodate the 12mm 95 O2 sensor. the whole thing will screw into the 18mm cat hole.