Chriz88DX

iTrader: (1)

I have a 87 s4 NA with the basic mods that will be street ported by the summer. my question is would the r tek system be a good choice for me? i am already useing a safc but when i installed my block off plate the idle quality went down when cold do to the cold start system removal. thanks alot in advance.

mazda_wes

iTrader: (6)

I used a 1.7 for a while with no safc and emissions blocked-off. My idle went crazy until I adjusted the variable resistor and set the tps several times over. It was a pain getting it right, but I finally got it running very well. I just went 2.1 and adjusted all of that again (variable resistor is now electronic) along with the afr at idle and it runs even better. The safc is built-in to a certain extent. It has it's limitations, but is very inclusive.

For s4 n/a, I would say that an rtek would be a good fit. I am not n/a though, so I can't 100% vouch for it.

Chriz88DX

iTrader: (1)

thanks man all i really want is a stable system since the safc "tricks" the ecu it does not feel constant all the time but my main ? is can the r tek run with out a tune

GMO-RX7

iTrader: (21)

I have an Rtek for an s4 that I was planning on using for a project but I need money for another project right now. Its a 1.5 I know you can get it upgraded. lmk if you are interested

mazda_wes

iTrader: (6)

The rtek runs on the stock basemaps and you tune from there, so yes you can run rtek without a tune. It's not too hard to tune a little by little with the rtek since it starts with the stock basemaps. Starting from zero is the hard part with engine management.

Chriz88DX

iTrader: (1)

ok cool thanks man the r tek seems to be the way to go but what are the main draw back cus i am hearing nothing but good about it?

mazda_wes

iTrader: (6)

limited injector size and that you can't remove the AFM are the only two real drawbacks. that doesn't matter much for naturally aspirated though.

Chriz88DX

iTrader: (1)

ok i have one more ? do you think i get the r tek tuned to to make decent power with aux ports open and pineapple racing insert sleeves.

mainly account for the extra air flow to make the car better to drive at low speeds

mazda_wes

iTrader: (6)

I can't really vouch for that, but I would imagine so. I would start with an install and basic tune, then move on to the other work.

Chriz88DX

iTrader: (1)

ok rtek will be here soon scheduled delivery date is today very excited. got the NA s4 2.0 will be tuning with palm m130 (got on ebay 7 bucks) this Friday i will order my wide band o2 i just can not wait to get rid of my safc it has been good but i know this will be alot more stable and help the car run smoother which is what i am really hoping to gain more than power now

Nick_d_TII

iTrader: (6)

Great! Are you going to be tuning a non turbo?

Chriz88DX

iTrader: (1)

yep i will have it tuned to get a base line before it is street ported.

Nick_d_TII

iTrader: (6)

Cool, but you're not going to be doing it yourself?

Chriz88DX

iTrader: (1)

no i will not i am a noob when it comes to efi tuning i know my limits.

Chriz88DX

iTrader: (1)

RTEK is here hell ya just hear the ups truck install time now

Nick_d_TII

iTrader: (6)

Well, if you were tuning a Turbo then I think you could go either way(DIY or pay a tuner), but since your tuning NA I'd say do it yourself.

There is another thread where a guy paid a tuner and since it took so long to do the tuning it wasn't very practical to Pay someone because the amount of hours it was taking...

I do understand there are some associated cost with DIY tuning the main one being a Wideband O2 sensor and controller, but they can be had for around ~$200 and cheaper for a used one(cheaper than paying for a tuner). I don't even use a WB gauge I just log the Wideband AFR's and review the logs.

I'm not sure what kind of gains on a naturally aspirated 13b can be had from tuning fuel and timing? For turbo cars there are upgraded injectors and boost/turbo's which create the need to adjust the fuel and timing curves to prevent detonation and squeeze the HP out of the Upgrades that the stock ecu and SAFC's can't.

IMO with NA tuning you really can't do no wrong when it comes to tuning, unless you radically advance timing which you wouldn't do. It will run either FAT or LEAN, but you gotta find that happy medium, which YOU can do. And It's fun playing/learning with it... Then when you get a turbo, YOU'LL know how to tune it.

Good luck... There are some good threads about tuning, give them a read...

Chriz88DX

iTrader: (1)

first off thanks alot nick for all the info.

after installing the system and looking at the maps it really makes complete sense. and now some of the stuff i read in Nicks AFR tuning methods thread makes since like the 3d map is easier to use for tuning adjustments.

But i also see how unlike the safc you make one two (lo and high) adjustments for a set rpm. i would think this would be atleast 3 hours of tunings( my freind got his honda tuned in 6 with no base tuning map.)

i think once my wide band gets here (ups must not like me) i think i will take a crack at it but i don't know about the timing part (need to do more reading on that)

and as for gains i have seen guys on here na get 18hp easy na so i think that is pretty do able. but the main thing now is preparation for the rebuild and street port (i just love the sound of a street port especially a aggressive port like i plan on getting.

i can see that i will need to upgrade my injectors asap the injector D/C is 50% and that is still super lean i can feel it plus my NB o2 sensor goes to 0.00 at wot untill 5k

Chriz88DX

iTrader: (1)

ok quick update i dialed in a little more fuel because the even the stock map have the o2 reading lean and it feels much better one ? tho why does the fuel map stop at 6672 that is weird
also i think i messed up the ecu ground when i took out my safc any know how repin the ecu plug i think i will need a special tool or some thing

thanks

Chriz88DX

iTrader: (1)

i noticed today my tps randomly jumps between 16% and 21% at idle is this normal also it does not go to 100% but at wot bounces between 94% and 95%

juan0

some rx7's have a bouncy idle and this is because as the tps contacts wear then they start shorting out, producing a signal that jumps from percent to percent, in your case, it jumps from 16-21%. this is why you have to adjust the tps when you idle starts bouncing. if you really want to get rid of this, buy a new one from the dealer, or if its not giving you any real problems don't trip

Chriz88DX

iTrader: (1)

ok cool it just makes the car sound like it is misfiring at idle.

tuning is comeing along great my goal run the 6 ports open while making decent tq down ow and pull hard up top. i am getting very close to reaching my goal for the lower end (<3500 RPM) what i had to do was do a full port and gasket match of the intake manifold and running all bur 9's. my bur 7's where holding to much heat and sarting to ping. also i run 89-93 octane gas also i have 4.30 rear end gears.

one major draw back on the NA timing map is that the stock setting retards the trailing coil 16 dregees below 3k i put it up to 10 advanced at 50% and above and and felt a huge difference. the car is so much more drivable but i really gained low end power with i increased fuel by 10 % and advanced the leading timing 7 dergees the car feels as tho the aux ports are closed but better way better. becuase while cruiseing i don't have to give it much throttle input to maintain speed. therefore allowing me to keep the exhuast nosie levels down.

I am very happy with my current development but i have decided on a wide band and it should be here soon so i can fine tune the high rpm fuel map