Another JWT S1 cam installation

[coolyun_98]

Yes, I finally finished putting in the S1 cams from JWT. This is a long story.

About 4 months ago I replaced the timing belt, but only found out that the VTC system is totally messed up. The intake sprockets leak oil, the VTC solenoids were weak. As a result, a lot of tapping and clicking noise coming from the engine. Given that my J is 15 years old, I thought to myself, what the hell, if I am going to get a new VTC system, I might as well get a new set of cams and lifters (they were making noise). So, I decided to replace whatever to fix up all problems once for all. At the end, I can get an almost like new J for about 3 grand, better than buying a new car. So, I jumped into it.

Other than the cams, I replaced the following items:

Fuel system:-6 x new 270cc (stock) injectors with all new o rings and insulators (injectors are known to go on older Js)-new fuel temp sensors (sometimes a bad fuel temp sensor will cause J to lose power after the engine is warm)-new fuel rails (they get dirty with time)-new fuel rubber hoses and clamps (they get hard and start to leak fuel with age)-new fuel damper/pressure regulator (they get dirty with time, drivability will decrease if they are clogged)

Engine control:-new denso oxygen sensors (have to replace these every 6k miles)-new egr valves (better replace it once the intake manifold is off, otherwise, you will have a hard time replacing this with the manifold on)-cleaned egr tubes (very dirty if you don't clean it every 6k miles)-new VTC solenoids (known to go bad if oil change interval is greater than 90 days)-new coolant temperature sensor and sensor (bad coolant temp sensor is known to cause bad idle)

Engine mechanical-24 new valve lifters (better replace it with the cams to avoid excessive wear on the cams)-new intake sprockets (leak oil, have to replace them. But normally, they can last quite a long time)-new timing belt + idler pulleys-new accessory belts + ac pulleys

Misc:-new ac compressor (my original compressor was out off oil, almost dead. I got a new OEM one off eBay for only 150, great deal)-new alternator (easy to replace it while the timing belt is off)-all electrical connectors are coated with dielectric grease (Js are known for rusty connector contacts. Dielectric grease will help to block air and moisture from entering the connectors)-rebuilt/cleaned idle air control valves (if you have a rough idle, try this)-clean throttle body and manifolds (you will be amazed how dirty your manifold is. Cleaning it will lower your emission and increase drivability a bit)

Ok. besides the above items, all new gaskets + o-rings + sealing all water/air hoses with high temperature silicon.

The end result? I started up the engine this afternoon and it was a bit rough due to the new cams (ECU need to learn for a short period of time to know how to work with the new cams). After breaking-in for 2500rpm for 20 mins, the engine idle SOOOOOOOOO quitely. I can clearly hear the injectors click. However, due to the nature the of cams, the idle has a very tiny bit of lope, but it is still very smooth. I don't know the real power gain as I have not driven the car (it needs another oil change after the break-in)

If you guys are in the process of replacing the stuff that I have already replaced and need some tips, I am here to help!

[coolyun_98]

I forgot, I replaced the knock sensor and its harness as well.

[yodawill2000]

Good job !!Bet she roars a little louder too !!

[kbflip02]

I forgot, I replaced the knock sensor and its harness as well.

i can tell you from experience that you will definately notice a power gain after 3k rpms....youll feel it kick it alot....the new cams will move the torque band slightly....also did you get reground cams????when i sent mine in to JWT they called me and told me they couldnt regrind them so i was lucky to get billet cams instaed...overall i think you will be very happy with the mod...its funny to me how you got the "while were in there..." bug just like i did...after having my J running for several months now i plan on port and polishing the heads and replacing the valves and valve springs next....that and port match the upper and lower intakes....anyways im going to stop rambling..congrats....-k

[coolyun_98]

THank man. Actually, ONe of reasons that I decided to go for the extra miles because of your post.

I mean...our J is a very nicely built car and It will be such a great project to fix her up. Your post is my inspiration!

Yes, I got the regrind ones from concept Z. I think Z1 motor sports is pretty decent at head + port works.

[kbflip02]

THank man. Actually, ONe of reasons that I decided to go for the extra miles because of your post.

I mean...our J is a very nicely built car and It will be such a great project to fix her up. Your post is my inspiration!

Yes, I got the regrind ones from concept Z. I think Z1 motor sports is pretty decent at head + port works.

well im glad i could inspire someone...im debating on doing the port/polish because im planning on doing a VH45 swap into a J...unfortunately i cant use mine b/c theres to much rust damage on the frame and im unsure if it would handle the extra torque...currently im in the market for another J30 shell...and a running Q45....ive got a buddy up in austin who is finishing up the Vh45 in his 300zx...either way i plan on keeping my J as a d/d...

[GerryO]

Absolutely amazing! Talk about really done right and a VERY thorough job.

How long did the entire process take?

And let us know if you ever decide to drop the oil pan.

[coolyun_98]

The whole process took about 2 months. Most of the time I had to wait for parts and look for proper tools. Also, I spent quite some time doing research. If you guys ever have any questions pulling the manifold, i will be very happy to help.

[kbflip02]

did you do the ECU too???

[coolyun_98]

I seriously considering doing the ECU. The only thing I worry about is running rich with the JET ECU. By thw way, I am located in Canada and emission test is quite strigent here.

Right now, the only mod is the cam. I keep the stock intake as some 300zx drivers feel that the stock intake will give more low end torque and more filtration against dirt.

[coolyun_98]

I just finished test driving my J.

My conclusion is WOW! Now the J pulls like a sports car! The difference is like between a camry and an integra type r.

With the JWT cams, new injectors, fuel rails, fuel regulators and damper, my J pulls SO strong and fast toward 4k rpm (i intend to keep it under 5k for the first 100 miles). Once I step on the gas, my J is just eager to rev.. I really have to watch my tech to keep the engine under 5k. It really reminds me of my friends integra type r.

Yes, I feel that the low-end torque is a bit less, but the cams make it up with a "fast-rev" characteristic. So, you will actually tap into the juicy mid-end torque quite easily.

Compain? Money. These cams are not cheap and the process takes a lot of dedication and research. This is definitely not a weekend project. If you really want to go this route, I suggest save at least 2~3 grands for parts and tools and at least p[lan for 2 weeks of down time.

[kbflip02]

Compain? Money. These cams are not cheap and the process takes a lot of dedication and research. This is definitely not a weekend project. If you really want to go this route, I suggest save at least 2~3 grands for parts and tools and at least p[lan for 2 weeks of down time.

and here we did it in 4 days....i was lucky though cause we had all the tools we needed...also i think the beer helped pass the time as well...well great job...id be interested to see some pics if you have any

[coolyun_98]

I will post some pic soon! Maybe a video clip of the exhaust

Man, you are good! It took me 2 weeks to swap the cams and seal up the valve covers. Most of the time, I was fighting with the egr valve and egr tubes. They are pretty hard to remove...

I guess lack of experience is probably the reason why it took me so long. B4, I only did very light DIY work on my J (like change brakes and wax the car). This is actually my first majot project.

[kbflip02]

im not exactly a jedi master so to speak...i had help though...the guy who helped me...my neighbor...has built many cars and pretty much walked me through everything...i can read the FSM all day long and undersand it...its the doing part that gets me...as far as the JET ecu's go im not sure how rich they run...but my Jim Wolf ecu runs rich as well however its not to the point where ill fail an emissions test or anything like that...i would reccomend the JWT ecu though from peresonal experience...whats next on your list of mods...