Finished my KONI Yellow adjustable strut inserts 8641-1439Sport install last night. Find install info on page 4 of my Cardomain page http://www.cardomain.com/ride/2248073/4. Got them off ebay from SOHI performance for $313 shipped.

If you know how to replace strut springs, you can do this. I installed them with OEM springs for now. Maybe I forgot how soft the OEM suspension is, but the ride is day and night compared to a GR-2/Eibach setup. On the soft setting, you don't feel the road. I will ride for a few more days to check for rattles or noise before I declare success.

I noticed that the lower rubber insulators protecting the springs from the lower strut brace were almost worn through. Contact between them could cause noise on rough road. Will get new ones for sure. I guess stiffer KYB/Eibach beat the heck out after only 25k.

 

Naice! Looks good, but definitely not something I'd attempt myself...for the time being at least

 

can you post a link on ebay that u bought it from

 

NICE!!! what r those other mods you got? The intake and MAF mods on your cardomain?

Kamski

 

can you elaborate more on the maf sensor drilling? how is that holding up? how is your gas mileage? slight decrease?

 

Mike seldom visits these forums, but when he does, he sure leaves a mark!

350z t-stat
Custom MAF
...and now this!

What he did to his MAF was intending to richen up the AFR due to the mods making his car run leaner...more holes in MAF=tricks it and more air=more fuel

 

Koni:

I used the Koni inserts for Infinity 00-05 I35. I looked at the specs from Monroe for length, travel, compression and 8641-1439 were the closest match. The insert is about 1/2 inch longer than the OEM.

http://cgi.ebay.com/ebaymotors/00-05...3790QQtcZphoto

MAF:
I was getting SES lights after new ECU, Y-pipe, etc. Got Autoenginuity software and saw that that I was running way too lean, more than the computer could compensate. It was around 16/1 to 18/1.

I studied the MAF and took a chance to get more air over the MAF wire located inside. Inside the MAF is like a maze (probabily to equalize some pressure). By creating holes in the back, it provided a shortcut, thus more air over the wire. I started with one tiny hole, and remeasured the air/fuel ratio until it got near 12-13. Now it was back within the specs where the ECU could adjust. As I hoped, gas mileage did not changed on the highway;30-31 on cruise @60mph. But remember, to make more power, you need to burn more gas. As you add mods, city joyriding will use more gas.

MAF mod was done last year and had no unusual effect that I have noticed.

 

I wrote a few times about the porting I did to enlarge the 3 smaller ports to have all 6 ports with the same diameter and same air column length. The polishing inside was to get more air flow at WOT. Since I had to remove the intake to install the phenolic gaskets, I did the porting/polishing on a used set of UIM/LUM ahead of time. I also put in new/colder spark plugs and partially plugged the EGR valve.

 

mike, on city, how much did it drop for you? i mean your normal driving b4/after the holes? i just have a cai and y pipe. [exhaust hopefully coming this summer if i can get a break from classes and get out the welder]. im thinkin of starting out with one hole b/c i do not have a way to measure it. i guess i could get a aem uego, i was using one of those on my boosted ek and worked pretty well imo.

 

Explanation:

Without the extra measured air (extra flow via MAF holes) the MAF tells the ECU to send little fuel, where the O2 sensors say I am way too lean (according to a/f tables in ECU). The 'trim' tables try to learn/adjust to this difference (as the car get old/out of specs). Stay too lean for too long (keeping the trims at max value for too long) and the ECU will flag the MAF or an O2 sensor as bad. The holes do not change the air/fuel ratio, or run richer. It merely keeps the trims near a zero value. My lower gas mileage is because I generate more HP, thus burning more fuel at WOT. Joyriding, WOT corner to corner gets more and more expensive.10-12mpg.

 

i see. i guess this is where i am confused at: you say the holes do not richen up the a/f ratio. so the trim tables richen up the a/f to a point? then how does it help to zero it out?

 

Wrong words, you are correct. The MAF holes tells the ECU that more air is going to the engine, thus more fuel is required. But remember, the O2 sensors were telling the ECU that the a/f was too lean and the ECU was re-adjusting the a/f mix based on the pre-programmed value in the ECU. But, the O2 sensor signals are always too late because the fuel has already burned. The difference between the MAF value and the actual O2 a/f values cause the ECU to add or substract 1 to the trims. Every few seconds, the ECU does this add/substract to the trims. I forget if the max value is 15 or 25. Having the MAF send the correct air flow value cause the O2 sensors to report back that the a/f is correct and this keeps the trims near zero. Operating with near zero trims keeps the a/f mix near the values pre-programmed in the ECU. Under various driving conditions (wot, start), the trims are reset to zero and the re-learning begins. During this re-learning, you get less than optimal a/f mix.

 

The Koni inserts are great. You have 720 degrees of rotation to go from soft to firm. The soft setting is great for not feeling any of the road bumps. At 180 or 360 degrees (1/2), the tires stick to the road, the car stays level, even in bumpy curves. The struts compress real fast but rebound as quickly. The OEM struts had very very slow rebound.

At 540 degrees (3/4), they begin to feel like the GR-2. Some cabin feeling from the bumps but impressive stability and reaction time. Still experimenting on this setting. Need to adjust rear AGX.

The Koni Yellow (sport) appear to have a softer range than AGX. Maybe because front is heavier.

 

Koni single-adjustables have fixed compression damping and adjustable rebound damping.

Because of this, ride is not greatly affected with firming up the dampers, but the car will seem to "hug the road" a lot more, e.g. when you go over sharp crests the car will hug the crest more tightly, keeping the ride height more controlled. When you go over a speed bump, the initial bump will not be felt more but the car will hug the contour of the bump more closely (it will fall more quickly as the bump goes back to normal road level).

Konis on full firm are not firm at all, at least for the 4th gen. I ride around on full firm all around with no complaints.

 

mike, ok i think i got it, here it goes: add mods, car leans out [varies by mod] -> ecu detects leanness from the o2 sensor and retards the car a bit to prevent detonation.

by adding the holes, the ecu detects a greater airflow thus compensating it by adding more fuel instead of auto-adjusting it by using the trim tables? when you said preprogrammed #'s, you mean a target a/f ratio to maintain?

if this isnt right, i guess im not understanding where the extra fuel is coming from and why.

i have a general idea of the tables because i had a boosted ek with a s200.

thanks again for the info!