*TOUCH*

iTrader: (29)

Is this possible???! i had no previous pinging issues while using Load based timing via my Rtek but since i've swithed to boost based ive noticed pinging starting in mid boost range (~7+ psi) and mid rpm rangin (3500+rpm). my intake temps have never passed 55C (130F) and i ALWAYS use 93 octane. thus i thought my problem was that my timing was too agressive, so i backed it off by 3 degrees in the 10-15 psi range, 2 degrees in the 5-10 range and 1 deg in the 0-5 range so that i could blend it into the vac section of the map. it still pinged so i retared it by another 2 degrees in all boost pressures for all rpms. so all totaled 5 deg in 10-15 psi, 4 deg in 5-10 psi and 3 deg in 0-5psi. all the while im hitting low 10 AFRs. so im out of ideas, unless something loose is playing tricks on my ears.

it should be noted that i have never heard pinging in a rotary before, so im basing it off my experience with piston engine pinging, which this sounds VERY similar. id have to assume that rotaries may sound different, but i dont kno if thats true??

if anyone has any ideas why this is happening, lemme kno. thanks

*TOUCH*

iTrader: (29)

o yea, forgot to mention, my mods are in my signature.

and they pinging is slight and spaced out. not happening rapidly and consecutively

arghx

iTrader: (3)

you can get misfire and detonation from being too rich sometimes. Ask BDC, he says he blew a motor that way. Make sure your timing is set correctly on your CAS and that your timing marks are accurate (crank pulley and hub are from the same engine).

I have posted timing maps in the Rtek forum you could use. There is a big thread in there. For a safe setup to start from (and safety is key right now), do a max of 15 degrees advance at 15psi with 12 split. You can run more advance at lower pressure. There are a bunch of ways to do it really. Definitely don't go less than 10 split over say 6 psi in your current situation.

jjwalker

I don't even know what pinging sounds like in a rotary. Is it the same prenounced coke bottle rattle like in a piston engine?

arghx

iTrader: (3)

only time I ever experienced pinging was when I overboosted to 18psi on my stock turbo. it was a loud thunk

Aaron Cake

iTrader: (1)

Low 10s is too rich for the stock ignition system in most cases. It's not surprising that it's causing misfires, which will cause pinging.

Tune for 11.5 across the board under boost, starting at 15 degrees of timing at 1 PSI and then taper down to 10 degrees by the time boost gets to the high teens. The difference in power will be dramatic and that is still a very safe tune.

Edit...Hell, 11.5 is too rich until about 5 PSI. I generally tune for 12-12.5 until 4-5 PSI then I start tapering down to 11s. I bring the fuel down to high 10s at higher boost (15 PSI+).

*TOUCH*

iTrader: (29)

jjwalker, thats what im trying to figure out haha

arghx, thank for the info, i actually used te map you posted at first, as it seems pretty standard from what ive seen other guys run, but i was pinging on that map, the retarded timing i said i did was applied to that map that you posted, but keeping the same split (fairly conservative split map imho, which was what i wanted until i can get to the dyno)

i have heard of ppl blowing there motors while running too rich, but i thought it had to be much richer than what im running (richest i have seen on mine is 10.2:1). even tho this is way to rich for the boost im pushing (im aiming to get closer to 11:1), this is all i seem to be able to pull out once the 1600ccs come on. the CAS is lined up correctly, i have checked it many times, but i will tell you that the crank pulley and the crank hub did come from different vehicles. timing was set via a timing light (as best as it could be since my idle is not "rocksolid") so i thought it would be ok??

thanks guys

*TOUCH*

iTrader: (29)

aaron, yea, im really thinking i need a more flexible ecu. the rtek only allows for +/- 37.5% fuel correction, and the highest sec. preset is 720cc, so its dumping in alot more fuel than needed and im at fuel negative already above the sec. injctor cut on point.

arghx, no, this definately does not sound like that. this sounds just like piston engine pinging. like a robot bird cirping or something. i think someone else described it as metallic popcorn popping? think its something playing tricks on me? either way, dont wanna chance it haha

BDC

I've got a different and much more self-incriminating theory about how mine went now but I agree with what you're saying. Low 10's:1 is pretty stinkin' fat!!

B

gxl90rx7

iTrader: (1)

what injector preset are you using in the rtek?

I think your problem is caused by the secondary injector transition. The stock transition parameters are
1) rpm > 3500
AND
2) boost > 0 psi

so you floor it at 2500 rpm, build 7 psi boost, but the secondaries wont come on until you cross 3500 rpm, then it hesitates

to tune the 1600's, you are probably taking out a lot of fuel above 3500 rpm and above 0psi. But the fuel map is interpolating between the fuel map cell above 3500 and the cells before 3500, so for a brief moment (under 3500 rpm) you will be running lean as the ecu is ramping down fuel, but the secondaries have not yet turned on

*TOUCH*

iTrader: (29)

im on the 720/720 preset (as close as i can get to what i have on the car).

i had thought about that before and that WAS a problem, but the 2.1 allows yo to adjust the transition rpm and i have done so that that there is no lean spot. i have an LC-1 hooked to a gauge displaying AFRs in real time and now i kno for sure when the sec come on (for starters my AFRs instantly drop by a whole point haha) and also because there is a secondary flag feature in the rtek that allows me to view/log when exactly the secondaries come on. in essence what im saying is that a leanspot whre the primaries are at teir limit and the sec. have not yet come on is not the case. altho if i hadnt already fixed that, itdefinately could be the problem.

either way, im starting to think that it probably is some sort of misfiring due to the rich AFRs. anyone have any comment on if there is a noise difference between that and regular detonation (like i said earlier, mine sounds remarkably similar to piston engine pinging, not the thud arghx described).

thanks so much for the responses guys

ChrisRX8PR

The sound is best described as "marbles in a can"....not like in a piston engine....

...ask me how I know....

Chris

*TOUCH*

iTrader: (29)

hmmmm....maybe this is not it then....?

Black Knight RX7 FC3S

iTrader: (7)

Thats definitly how it sounds like......and it scared the **** out of me. lol
The sound was definitly comming from the engine bay. i thought something broke off lol.

When I was thrashing on the highway at like 1am, my afr was at 10.3 at 7-8k rpm on 10 lbs and I was pinging. I set my tuning to be WAY conservertive. I pulled over right away, thinking it was a misfire from too much fuel, I leaned it out to 11-11.5 and it was still pinging. Pulled over again and tried my luck and advance the timing just a little bit (always carry a timing gun ), went for test run and the pinging stop. Mind you, this is on a rtek 1.8 so all I could do was from the cas, I forgot the degree I had since this was a month ago, and I barely manage to remember anything from a week ago lol.

*TOUCH*

iTrader: (29)

so yours was pinging from being retarded too far??

im starting to think more and more it was not pinging because mine was definately higher pitched and more subtle then marbles in a can...i think i ma take a vid. what else could it be?? clutch effing up? ive been experiencing some slipping before on it... thanks again guys

gxl90rx7

iTrader: (1)

ive heard mine ping several times sounded different both times. it sounded like a hammer hitting metal near the turbo one time (light pinging around 3500 rpm), another time it just made a tick sound and the whole car studdered (4th gear, 15 psi)

*TOUCH*

iTrader: (29)

ok, now im thoroughly confused haha....

also, arghx got me thinking earlier about my hub and pulley being from different cars. this is ok since i went behind it and set it with a gun right? or no? can someone explain this to me? thanks

arghx

iTrader: (3)

Rotary Resurrection explained this in a thread a long time ago. It has to do with variations in the way Mazda manufactured the crank pulley and hub. Even though you lined it up with a gun, the timing can still be wrong if the pulley and hub are not matched. The yellow -5 BTDC leading mark is only really -5 if it's bolted to the hub it was manufactured with.

I actually bought a brand new crank pulley from Mazda because of this (didn't trust the pulley that was on there) and it came with a hub. Why would Mazda give me a hub if they weren't meant to be matched as a set? The pulley and hub were like $180 shipped (?) from Ray Crowe at Malloy Mazda, a forum vendor. It seems steep, but it was cheaper than a new motor. And sometimes peace of mind is priceless.

cell phone pic of a brand new OEM pulley/hub assembly after I put it on during the motor build:



You can't see the yellow and red marks but they're there as well, opposite the paint marks. It comes with the hub and all the pieces installed together with bolts in there and all the holes lined up. I didn't want any "good enough" DIY timing marks on a 400whp build. I didn't want any aftermarket underdrive pulleys with weird marks (I think some of them are not at the factory -5 -20). I just wanted my timing to be set like Mazda did it back in 1987.

*TOUCH*

iTrader: (29)

man, that seems retarded as hell (not you, but on mazdas part) i have never heard of that on any other engine but i guess leave it to roataries... has anyone ever been able to estimate how far it could be off?

agreed, but if we are talking about a variation of say +/- 1%, I cant justify a 180 dollar buy, altho i can see why you did.

lastly, i believe i solved the problem...i switched out my 800ccs to the secondaries and plugged some factory 550ccs into the primaries. i drove around for a bit and messed had my bud adjust the fuel settings...long story short, after some fuel tuning, under full boost (11~12 psi as of now) and at high 11s (a bit leaner tha i feel comfortable with) i got no "pinging"!!! i guess it was as everyone else said, just too rich and causing misfiring "pinging" or w/e. so now im gonna start saving towards a real standalone so i can have more adjustability...
in the mean time im on the look out for somethin in the neighborhood of 1000~1300cc injectors! (i duno what the next increment is after 1000cc thats commonly sold)
thanks for all the help and wisdom guys!!

BDC

You're right, Arghx. I've run into that a number of times. I used a Racing Beat pulley/hub combo piece to chisel known good marks on a factory pulley/hub combination (pair) here. It's a pervasive enough problem w/ the older FC and Cosmo blocks that I take that pulley/hub combo with me when I go out of town.

B

arghx

iTrader: (3)

I thought I read somewhere that the Racing Beat pulley timing marks are not at -5 -20, but at whatever it is for the 12A?

arghx

iTrader: (3)

We're not. A good friend of mine blew a motor during breakin (wasn't boosting it, but it had very low compression) because the timing marks were off. It was so retarded that it caused all sorts of problems resulting in a destroyed rotor bearing. I'm sure there are more horror stories out there.

BDC

The Racing Beat pulley/hub has marks 10*, 0*, 10*, then 20*BTDC.

j9fd3s

iTrader: (3)

ive been checking it when the motor is apart too.

ive seen people drill out the 4th hole in the pulley so they could put it together wrong :headslap:

RotaryEvolution

iTrader: (30)

no offense but the Rtek is a piece of **** standalone.

oops, that was offensive...

welcome to on the job R+D with a product that can cost you a motor. if they wanted to build and sell a true standalone then you don't test and sell them based off of a stock car, you have to push it to the limit and find issues with it. yes, the timing maps are far too aggressive for anything above a stock system(at least they were when i saw the first version of this ECU and **** when i saw the maps and knew why the motor popped while he was tuning it).