Nice write up...breather mods are great when tuned...lol.

 

Well it's just not about breathing, it is also about scavaging and backpressure. If you haven't noticed the stock Nissan headers suck. There main purpose and design was to increase maximum back pressure, in order for the EGR valve to do it's job by consuming hot exhaust gas ( which takes up space in the intake manifold and decreasing the amount of air (positive intake charge) that could of been consumed through each cylinder. Most USDM's were designed this way to increase gas mileage, by shrinking the pulse width (or rate of injection). This is also used to use proper exhaust gas reciculation, (which of course we use as a benefit for our USDM's to lower NOX emissions. (which in my mind is retarded the KA runs at under a 9.6:1 compression which I don't believe would get NOX levels high enough not to pass, unless of course the pulse width was to short creating a really lean mix, which would raise chamber tempratures). That inevetably wouldn't happen though due to the fact that Nissan tunes a 7% fuel richner at lower throttle, (which means that fuel has infact already been increased to the intake charge, more fuel than air in the A/F ratio). This kind of serves as a oximoron and kills performance, and at the same time isn't as fuel conservative as once thought with the old methods of tuning back in the late 80's and early 90's.
Now there is also a problem with scavaging on the stock headers, scavaging is what allows the exhaust pulses to run back up to the cylinder and possible double or triple the load on the positive intake charge(maybe in small doses though since the cams don't do to much overlap), (again taking space that clean air could of used and been consumed by the engine). Many flaws by design created the KA to become a very anemic engine, and I believe that the main focus is infact to the exhaust system and the manner in which it recirculates hot exhaust gasses.
Problem one with stock header, runners are to short allowing pulses to run back up the cylinder at earlier rates, they were also made to increase back pressure, shorter runners make it easier for the EGR to collect exhaust gasses(obviously bad for a performance enhancer). ( I always screw up with the differences between back pressure and scavaging so if I didn't use correct terms some one please correct me.)
Second problem is the small exhaust system at 1.75", exhaust is a waste or biproduct, the more you slow down the pulse the harder it is for the engine to function. Kind of like when some one takes a constopated shiat and is stuck on the toilet for an hour. (It slows everything down), hopefully an easy analogy to understand.
Now look at the stock ecu tune, obviously it is a garbage tune using horrible ignition timing in order to make up for all this recirculated waste that passes through the engine. Obviously retuning the ecu for better injection rates and less exhaust gass recirculation will infact increase power tremendously (just like that dyno that I showed earlier). hopefully that explains why so called "breather mods" affect the KA so dramatically.
I mean just with a header,pulley, and injen intake the KA relatively pulls 27 additional HP at the flywheel (without a CAT back exhaust or ecu tune), as shown by this dyno with out a tune.

 

awesome thread. you really got me looking forward to my ka build up coming up soon.

 

good stuff

 

Great write up. Another cheap alternative for fuel manigment would be megasquirt. I'm planning on running megasquirt with a ford cobra MAF.

 

Great info as always! You are a true help to the 240 community.

I may have asked this before but how many miles do you have on that engine?

 

BigVinnie = KA prophet
Wish I had the resources to build a na ka up to 200-220 whp. Finally some proof the KA is a more than capable engine.
Could you clarify to the contact info for the s14 rom tune. Definately worth it since like you say nissan tunes are garbage
programed for fuel econ.
Do I get in touch with Devious KA (Gabe Z) of NICO?

Do s14's have secondary butterflys?

 

nice

been looking at the mikuni carbs and such for the ka24e myself...upgraded pistons, cam, fuel pump...probably won't be very streetable but I'm looking into making the 240 a track car soon, just gotta find a decent daily driver

 

F$CK YEAH! Show me that set up when you get it running!!!!!
Dude where did you get the spoon feed from that is hilarious, assuming you did it on adobe....LOL

Yes in trhe KA section of nico in engines listing.....

No OBD2's have no butterfly's nothins for you to worry about...



My odometer stopped not to long ago, but the compression is strong with variables in the cylinders between 169~172...

 

got the pic off of Zilvia and just photoshopped it real quick. Will definitely post pics, right now I'm still in the sourcing parts phase, although it seems like courtesy parts has me covered on just about everything...

 

more info on devious ka so this guy can tune my ecu for how much??

 

You can get a hold of Devious at his own forum. Even retune your own ECU if you chose too.
http://eccs.hybridka.com/

or here at NICO
http://forums.********.com/zeroforum?id=130

6months ago he was charging me $100 for a tune, and shipping was $50 ($150 total). That was for OBD1, I have no idea what he is charging for OBD2...

 

BigVinnie, all this stuff you done does it leave your car street legal? i know u drive it all the time but will it let me pass air care(mine is comming up soon) because for now mine is a daily driver.

 

I'm street legal with all of my modifications. Even get the engine tested from one of my boys that is a smog tech. Last test I didn't pass due to the distributor being advanced at 23BTDC. Hydro carbons were to high, which means if there is fuel in emissions at burn off the engine isn't making proper power. Set the distributor back to 20BTDC and passed with really low emissions even for having a high flow cat, and exhaust system.....

 

Bump with an update.
Gabe does direct sales for ecu tuning at http://www.hybridka.com/completeecus.htm