muythaibxr

Nope, no screen grabs as of right now. I'll check my laptop at home to see if I can find the original S5 maps I used.

Ken

rotarygod

iTrader: (1)

Hopefully everyone knows this already but if you are going to try any of these settings, make absolutely sure you've got enough fuel!!! Start rich and tune down. Don't automatically assume your fuel settings are going to work good with these timing settings. Your porting and turbo used will also affect how well these work on your car. Try them. Just be careful and don't automatically assume all will be instantly well when you load them in. There is always some tweaking to be done.

toplessFC3Sman

iTrader: (1)

yea, that was why i was working up to them, so i could stay on top of fuel tuning, and just to incrementally make sure everything was working right and sounded/felt fine

BDC

Naaah Fred, it just automatically works. Just wave your magic wand and "poof!" instant horsepower and torque! Don't you know that's how cars work?

B

joeylyrech

iTrader: (11)

hey BDC im working on a HB high comp turbo setup(s4 rotors)and im close to start
the motor but i dont have a base timing,split tables,i been searching for days but there is no info about running a BP with MS,did you have any tips or ideas that are you willing to share thank Joey

AlexG13B

iTrader: (7)

he has a timing map on his link for a halfbridgeport

twister7

iTrader: (3)

Bdc could you please give me some more details on the engine that was used with the The Half-bridge port map with the advance in the 40's such as witch housings, what rotors and what front pulley?

BDC

It's from mine, primarily. S5 4-port turbo block, S4 turbo 8.5:1 rotors. Front pulley? Atkins Rotary aircraft setup, but that shouldn't matter.

B

joeylyrech

iTrader: (11)

so i need to play a bit if i use this maps cause my setup use high comp 9.4.1 rotors
and s4 turbo housings,by the way what injector combo and turbo are you running BDC?Thanks Joey

BDC

Eh, take out 1* across the board, Joey. It's a pump gas setup and it already has a fair bit of retard in it under load so the change from 8.5:1 to 9.4:1 won't make much diff but wouldn't hurt to start on the conservative end.

My injector combo is 720/1680 at a 40psi base pressure.

B

twister7

iTrader: (3)

The reason why i ask is i was wounding how you're car was running good with the leading plugs firing on the rotor flank,the pic is a s4ts rotor, front pulley,and housing @45 degrees of advance?(give or take 2 degrees depending on how the front pulley was bolted on)


Then i started to think maybe he had s4 housing with s4 rotors in a s5 engine with a s5 front pulley witch would make you think u are firing @45 when u are really firing @ around 35 the front pulleys are different between the s4 and s5 engines the is around about a 10 degree differance and the s5 pulley is a tad bigger (see pics)!
red pulley is a s4 silver is a s5

here is a pic of what i mean buy rotor flank the X (to give an idea) is were u would be firing on at 45 out side of the chamber!

Here are pic with the red s4 pulley set at -5 factory mark then with the silver s5 pulley installed with out moving the e-shaft see the differance!*(NOTE: each mark is 5 degrees)

10 degrees differance (give or take a degree or 2)


More Pic's
s4 housing rotor and pulley all in the below pics!
s4 @ 30 degrees advanced

s4 @ 35 degrees advanced (see the rotor flank starting to cover up the leading plug hole!)

s4 @ 40 degrees advanced (look were the flank is now)

If I am wrong about the s5 front pulley and u do have a s4 front pulley installed,
Please explain cause i don't under stand how it would run good firing out side of the chamber if it would even fire at all?FYI buy no means was any of this meant to offend you what so ever, i think it is great to have a experienced rotary tuner on the ms forum to give out pointers

joeylyrech

iTrader: (11)

thanks BDC,i will get back to you with the results

2Lucky2tha7

iTrader: (3)

Looks like I need to advance my timing 10 degrees after reading about the pulley marks. I'm currently using series 4 housings and using the Mazdatrix/Racing Beat underdrive pulley. I ended up marking the factory leading -5 degree mark on the new pulley and set it to that. I used the series 5 pulley to do this however by putting it on, moving it to the mark, taking it off, and then marking the new pulley. But that's for series 5 housings though. Looks like I've been 10 degrees off this whole time. Also, I decided to use BDC's timing map for my streetported 4-port (N/A application actually)
Brian

joeylyrech

iTrader: (11)

so twister do you think that i should change my front pulley to a S4 turbo(i have a s5 turbo installed now)to take care of this 10 degrees diference,i already subtracted 1* all around my advance and trailing settings like BDC sugested but i want to be safe before i start this motor up thanks for inputs(BDC and twister)

BDC

You're VERY right about the difference in pulleys!! This is something I ran into a few years ago by accident. I had no idea I'd mixed up the pulleys and front hubs. Having them mixed up will send your advance off about 13* too far forward or too far behind. It's therefore imperative to make sure that you keep the pulley/front hub combo together.

Mine is correct -- I used a Racing Beat pulley/hub (underdrive) unit with known-good timing marks to mark my pair. This is a common enough problem on the FC's that when I go out of town to tune cars I take a known-good combo with me incase I detect that their's is off.

B

BDC

Twister7, thanks for taking the pictures of the rotor in the housings. I need to take a closer look at this. The only place I'm having it fire that early is at low RPM pretty deep into vacuum. Otherwise, it will go about 40* and then forward. Based on this, I need to see if I'm firing the lead too early by accident. It does seem to run and function just fine. I'm running S5 rotor housings, btw.

I've got some driving time today while I run an errand up to Dallas and back. I'll try goofing with this and see if it makes any appreciable change by pulling a bit of adv out and see what happens.

B

twister7

iTrader: (3)

All i know so far is u have to keep the front pulley and rotor housing combo the same . s4 housing with s4 front pulley s5 housings with s5 front pulley! read my replys

twister7

iTrader: (3)

I am not seeing any differance when swapping a s4 pulley hub for a s5 pulley hub are u ? If so let me know so i can check a few more (i have 10 or 15) and make sure the s5 one i pulled is a s5, also i don't see any differance in the front cover from s4 to s5 other than the s5's pointer is higher up to allow for the hair bigger s5 pulley,,only thing left is the e-shaft i really don't think mazda would change the key way but who knows, i need to figure out a way to check that!

twister7

iTrader: (3)

When i was search a wile back i did come across a .txt file that was said to be a stock s4 n/a and a stock s4t2 timing map it was on the nopistons forum! The map if it is a stock s4t2 map did show 42.5 deg advance at 6400 to 7168 at what i think is very very light loads (off throttle like loads) and 40.4 at 3072, but because Mazda does not use a map based system I am not sure.At 42.5 about half the plug hole would be covered buy the rotor flank.Any ways here they are!
FYI like i said i don't know if these are stock maps for sure or not!!!!

Oh ya if u are running s5 housing one need for more advance might be (Rotary engine by Kenichi Yamamoto on page 53) spark plugs installed away from the minor axis in the leading direction will reduce emissions but deteriorate the fuel consumption because the initiation of combustion in the less squishing area causes slow combustion speed! (THIS MAY CAUSE IT TO NEED MORE ADVANCE)

2Lucky2tha7

iTrader: (3)

As far as I know, the keyway has NEVER changed on the eccentric shaft for the 13B since the 70's up until the current renesis engine. Also, as far as I know, the pulley hubs have stayed the same from 79-91. I'm only aware of the actual pulleys being different between series 4 and series 5 housings.
I just need to go find out now where I should EXACTLY mark the factory -5 degree mark on my Racing Beat pulley for series 4 housings.

2Lucky2tha7

iTrader: (3)

^^do you have a link or pic??

BDC

The crankshafts are no different in terms of the front keyway aligning TDC at 9 o'clock, but they most assuredly have changed front hubs somewhere in that mix. I wound up having 2 or 3 different kinds from what I recall. It was aggravating enough to force me to not only make a known-good pulley/hub combo but also carry one with me. I've seen cars that were 13* too far advanced across the board as well as 13* too far retarded. Happened on my car once, actually.

B

Edit: to bold and stress a particular point

BDC

No, no, no -- Static timing will not change from housing series to housing series even though the lead plug placement on the S4 housing is higher than the latter! If anything, it may demand a closer look at when spark is being fired under load if the compression ratio of the motor is the same between the two, but as far as setting a known good timing mark? Absolutely not. TDC, regardless of the housing, is set with the front rotor at TDC and the crankshaft's front keyway being at 9 o'clock. This is not something you want to fool with!!

B

rotarygod

iTrader: (1)

I wish load was called out in those charts. I'm a bit confused looking at them. RPM we know but load can either be low at the bottom or high at the bottom. If load is low at the bottom, then the max advance timing under boost is over 40 and split is negative! If load is high at the bottom then that means 14+ degrees of advance at idle with 28 degrees of total advance up top. That makes more sense. I'd still love to know what each load point is in terms of kpa.

2Lucky2tha7

iTrader: (3)

Let me see if I can ask this correctly:
For my setup (series 4 housings, series 5 N/A rotating assembly, Racing Beat pulley), where should I "zero" my timing on the pulley? Should I find a series 4 hub/pulley setup and set it to the factory mark, or should I set it to 0 degrees TDC on the Racing Beat pulley? I am using your timing map by the way. After reading through all this pulley and timing difference stuff between the series 4 and 5 housings, and considering a have an aftermarket RB pulley, I am a bit stumped. Can you help clarify this for me? I know my timing is definitely off, but I need to know where to exactly set it to.