30psi+ Br7Es @ .019", 18* peak (help with misfire)

[turboglenn]

Well, my setup is the Hx40 compressor at 30psi, BR7ES plugs gapped to .019 on stock ignition coils no CDI, and timing WAS at 16* peak torque and 19* peak RPM

Now twice in a row i've lifted the head on this combo, once there was no misfire but after putting the car back together with the cyclone manifold and running only 17* timing peak (all else the same) I was getting a single mis-fire at about 5k-5500 RPM that has a loud pop with it and this second time lifted the head immediately (i can't have this happen again!!)

Anyway, i'mgetting my L19's todayu and putting them in on the new composite gasket but what i'm trying to eliminate is this POP misfire.. It's not like normal spark blow out where the car breaks up steadily from one point on,it's just one big POP at about 5250 or so and then the car revs out cleanly, timing is about 15* at this point and the plugs are gapped so damn tight compared to most others on similar setups that i can't figure out what the hell is going on

I can't figure out if i'm solely lifting then head from airflow and cylinder pressures or if this pop is some how tied into it all.. But i'm concerned because my plug gaps seem to be WAY off compared to everyone else on the same boost, e85, timing levels and so on.. If i gap them any wider i get crazy blow out all through the up top but iut's the normal silent blow out...what is this loud popping misfire i'm getting???

Anyway, i can post excel format ogs for anyone interested or wanting them, but i'm trying tofigure out what is causing not only this mis-fire but for me to need to run such a tight gap on NGK 7 heat range plugs???

Also, with my turbo and boost range it should be in the airflow for 550+ HP (8 blade that flows most of it's air at lower psi comparedtothe other holsets that need to be in excess of 30 to get going) so i don't think that my timing was excessive but is it more the airflow or timing that lifted the hgead the first time when there was no backfire/ppping/misfire??

I'm lost on this one because everything else in the tune is spot on, and when it doesn't misfire it runs super perfect as well

I can do a 1 through 3 gear pull and it's as follows...1st gear= great, 2nd gear switch is still awesome, hit 3rd and as soon as the turbo recovers boost and i start really pulling i get the bad misfre/pop and if i'm at lower boosts it doesn't do it, so i keep getting convinced

tested every coil pack set at my house and they all ohmout the same being within spec at the secondary winding but ican't get any of them to read right (below 1 ohm) at the back side where the ignitor hooks in

 

[abaum565]

Have you checked your fuel pressure regulator for leaks? It may be bleeding off a tiny bit of pressure, causing a sudden lean out and popping. I've had this exact situation happen and also thought it was spark blowout.

Also I highly doubt your making 550HP (especially to the wheels) on that turbo and boost level. No matter what compressor you have these things need more boost to make that kind of power.

Lifting the head on that combo and boost level is also strange, I just put 37psi and 68lb/min through a composite gasket and standard arps without issue. Everyones set up is different, but something doesn't add up there.

Also I didn't see you mention what your AFR were?

 

[turboglenn]

yea,i didn't think it was 550'ish to the wheels either but the only map i could find of theirs for this compressor was hard to read (like all holset maps) and the math i used to convert their airflow showed 61lb/min but who knows i just said less than what i came up with cause i thought it was wrong.. I was creeping to 33 at some points though, but to be honest it breaks all 4 tires loose in 2nd at a good tune at 28psi (when it wasn't blowing out) and before i lifted the head the first time

First time it lifted was at 30psi (slightly creeping over that) and when i did compression checks all was 180psi yet there was coolant sprayed all over the engine bay and the gasket was blown at the coolant passages on cyl # 4

next time it blew it went on cylinder number 3 and it was during the misfire, after the lifting experience the head bolts actually felt spongy when tightening them this last HG install and i know they are stretched now (this time the gasket blew out of the back of the block and had a steady stream of coolant pooring from cylinder 3- again compression was straight at 180 psi per cylinder)

i'm pickking up some l19's today though so i can get back to tuning

I have seen yours or some one elses post about the AFPR and i did check that it was holding and it is doing fine, plus the logs at 180 frames per second never show a lean condition unless i'm in steady spark blow out and then it's because there's no burn going on

I haven't done a real calculatiopn ofused fuel to see where the power should really be at in this boost range but i tell you one thing it feels WAY better than the 438hp i was doing on the old turbo, plus i have 9:! pistons and am on e85 so i'm not sure how much difference in air usage that makes but i lknow it pulls more power out of the same amount of airflow by making better use of it (compared to the same airflow on a pump gas tune with lower comp pistons)

i'm still baffled, trying to find some NGK wires locally to replace the 10 year old magnecores just in case that'sthe issue (they have got a few bad spots i've patched in the past)

 

[airmail96]

Is switching to a colder plug an option, maybe try running 8s

 

[abaum565]

post a log, and what were your afr's like?

 

[blackrosenova40]

Id also say go with a colder plug. E85 requires an even colder plug as it is susceptible to preignition more than pump gas. Id immediatly try 9's to see if the issue dissapears.

 

[awddsm95]

This is in no way ment to be disrespectful, as I am well aware of your experience tuning (from all your posts on these forums), but have you considered your tune to be too aggressive? 16degrees peak seems way to high with that turbo and boost level. I know it's just 30 psi, but your also probably running quite a bit leaner than a lot of other people tune for on e85 (again, an assumption from reading all your post over the years). I don't care if your computer isn't showing any knock. What's ironic is that your blowing it around peak torque where knock is most prevalient. Maybe what your hearing isn't a misfire, but some serious knock.

I tune customer cars pretty much on a continuous basis on ethanol, and have tuned at least 5 that make right around the 800awhp mark on e85 or e98 @ 40+psi boost, when these cars are turned down around the 30 psi mark, the have around 12degrees peak in them. Your only ramping 3 degrees from peak to max, I'm use to seeing 4-6 ramp from ~ 6000 to 9000.

Cylinder heads effect timing quite a bit. Do you have a 1g or 2g head? The 2g head requires less timing. I've worked with some guys running low 9s high 8s that were running high timing and having HG issues, I suggested them to pull some timing out, and there cars stopped blowing HGs and still went just as fast. What is your AFR at peak?

 

[abaum565]

Wouldn't hurt to try a colder plug. On the stock 6 bolt bottom end I rand a br7es gapped at .019 and 37psi without issue though.

 

[turboglenn]

I was thinking about picking up a fresh set of 7's and a set of 8's for experimentation, sady i've called all the autop parts chains and NO ONE has any NGK wires for trhe eclipse in (part number 9634) So i'm wondering if there's any other "budget" wire that can handle these levels of boost and power well??? ( i will NOT run accells i had them a long time ago and they went out every other week and i had to repolace them to keep from blwiong out spark on a 57 trim at 20psi)

ANyway... here's a little backing that 550hp is possible at 30psi'ish, depending on the dyno brand anyway ( this guy made 505 at 29 on a mustang dyno (same type i dyno'd my 438hp on) But that would be a solid 550whp on a dynojet for sure
http://www.dsmtuners.com/forums/dyno-talk/413726-505-awhp-hx40.html

So.. are any of the house brand wires any good ????

I'm leaving in about 30 minutes to make an hour drive to get my L19's and then i'm coming home to put them in one-by-one just like most people do when they get ARP's for the first time and don't wannapull the head to put em in

Anyway.. HOping this works out.. I was wondering what you guys think of opening up the gap on the plugs a litte more and the chances that it might help in the WOT areas?? I mean i have heard that the gap can be too small and i know it effects idle/cruise and the way the engine runs in those areas

leaving now on the bike tio go get my L19's Woot woot!!!

Leaving the car to sty cool so i can install themwhen i get back,... mapquest says an hour and 19 minutes each way,i bet i can shave that down

This is in no way ment to be disrespectful, as I am well aware of your experience tuning (from all your posts on these forums), but have you considered your tune to be too aggressive? 16degrees peak seems way to high with that turbo and boost level. I know it's just 30 psi, but your also probably running quite a bit leaner than a lot of other people tune for on e85 (again, an assumption from reading all your post over the years). I don't care if your computer isn't showing any knock. What's ironic is that your blowing it around peak torque where knock is most prevalient. Maybe what your hearing isn't a misfire, but some serious knock.

I tune customer cars pretty much on a continuous basis on ethanol, and have tuned at least 5 that make right around the 800awhp mark on e85 or e98 @ 40+psi boost, when these cars are turned down around the 30 psi mark, the have around 12degrees peak in them. Your only ramping 3 degrees from peak to max, I'm use to seeing 4-6 ramp from ~ 6000 to 9000.

Cylinder heads effect timing quite a bit. Do you have a 1g or 2g head? The 2g head requires less timing. I've worked with some guys running low 9s high 8s that were running high timing and having HG issues, I suggested them to pull some timing out, and there cars stopped blowing HGs and still went just as fast. What is your AFR at peak?

Hey its all good, no disrespect taken!@ And yea i considered the tune and then i backed the timing down to 11* peak torque/spool and only 15* peak RPM, most times a "tune based" top end ignition issue is lack of enough advance, but i did think that the advance could have cxaused cylinder pressures to be too high causing the lifting f the head. aLSO MY AFR's are richer than usual since i've put the 1600's in and have been tuning in the new turbo, i never get leaner than say 11.5:1 at this point in time at 30psi

I have a 1g head, and the "ramping" everyone so commonly thinks is mandatory is actually a factory turbo car safety measure.. most purpose built race engines and cars will have a steady advance in them from right off idle, turbos redtarding for boost pressure and then only adding what advance is needed for the speeding upo of piston speeds.. i've gone to so many tuning seminars to get trained on products that I do know enough about the curve to know what i'm doing and also that too much timing "swing" (or attack rate) in the RPM band causes knock. not to say there's not a time for fast advance.

If i had a load bearing dyno where i could sweep the curve i could find MBT but from all my experience around 14-16* is good on pump fuels for MBT and ethanopl does require more advance

anyway i'm off to get the parts so i can get back and put em in..

ALso i'm trying the cooler plug so everyone knows..

 

[MY1GDSM]

Not sure what help I can be... Though curious what is up here. hopefully the L19's help keep things together if it's just cylinder pressures.

But,
Glen if you could post any logs you already have of when it was happening... .

I'd like to take a look, I don't IMHO don't see why your having these issues, I know we run somewhat similar timing maps(in my own car)... . Though I'd be comparing apples to oranges with our cars if I tried.

What all has changed on the car since just before you lift the head last?

 

[turboglenn]

I'll get a recent log from between the two HG failures to post up here after istretch fromthe 200 milemorning motorcycle ride ijust made straight there and back for my L19's

anyone know the torque spec with ARP moly lube? I'm seeing ~ 100ft/lbs shouted out te most

NVM,straight from ARP 100 with moly, 120 with oil
http://122.148.77.132/4gt-manuals/ARP & 4G63T SPECS.pdf

edit: HOLY Stretch ARmstrongStud-man!!!!!

Ok, wanna talk stretched hea studs (these are the regular ARPsMind you. Most of them are averaging a floating variance in length of about .003 - .005" thi being the ones that are not "really streched" from longest to shortest, Then there's the BAD ONES.. I have 3 of the studs that are ranging in stretch being the low of .015 to the high of .018" longer tan the longest of the normal looking ones..They are so bad you can just stand them up next to each other and see it without even getting down eye level with the tops!!!! I was shocked and amazed, I don't know how none of these snapped on the last install, you can visibly see the "hour glass" shape in the threadson the really strertched ones as well, this is rediculouse. I'm not sure ifit'smore due to the heat and several use cycles that went on the bolts or the amount of stress placed on them while hot in the engine when the head lifted.. Iknow the 3 really bad ones stretched on the last install because i felt them get "soft" halfway through the torqueingand then finally tighten up

once I clean them up good and label them i'll post some pics and see if it shows good on the net too

Needless to say i have the L19's installed and i'm feeling confident in the engine again (i've been afraid to go WOT since installing this last head gasket)

These extensive signs of damage may be why i'm able to lift the head so easy under any little misfire at any decent boost level now as well, i just wish i knew what the initial cause of failure was... The one thing i can be glad of is that i KNOW i had an issue, not "i think the studs were bad" them fockers are just plain shot, and now i know i have the issue fixed, ijust wonder about the flatness of the head now

now i just need to find some NGK wires and get a freh set of plugs in the car and i'm read to play again

edit: here's some logs, the two labeled 30psi are pretty good but all of them hav data that is relevant some have lower timing curves than others as well

they all open in excel and in the last colum to the right if isaved them correctly you should see a converted value for the 0-5v signal logged as "air/Fuel" in colum "E"

if they arn't converted you can just paste this into the colum to the right of the last data value in the 4th cell down

=sum(e4/1000)*2+10)

hit enter after pasting and drag down from the cells rigt lower corner to convert the entire tables values

 

[abaum565]

Wow....thats a lot of stretch. Many guys use the standard arps to levels well beyond this too.

 

[Aphix]

I may be wrong, but I just looked up the torque specs on the 7 bolt studs from ARP with moly the other day, and they stated 86. I also read most guys who put em at 100 dont reuse them due to bolt stretch. So maybe your bolt stretch arised from the over torquing. Unless my torque specs I looked up are wrong or differ between 11mm and 12mm.

I was also going to say you should go out to your car tonight and take a look at the wires in the dark to see if there's any shorts going on. Beans is running BPR6ES @ .028" @ 35ish psi on his HX40 last time I checked.

 

[turboglenn]

Yea,more than i've ever seen on an ARP anyway, i usually michead bolts when they come out just for my own data collecting habbits but this is unreal

I got the L19's in and went to put gas in the car (about 7-9 miles each way in city traffic)

To be honest i was really affraid to just lay into so i spent most of it either bogging through the first 15psi checking AFR's and adjusting them at those low ranges, and then got into making short "spikes" to WOT and opening the wastegate.. boost was a little high in the 25psi range and i turned it down to 22 at one point, but one thing i found is that the cyclone manifold which i put on after the first HG popped, andbarely got to tune on before the seond let go, it' has made the areas before 4500 pig rich and then in the transition when the runners open up the car kinda dips rich and then leans when the valves open only to swqay back rich again by5100 RPM (really rich)

I was getting regular spark blow out again (damnit!!) but i did see AFR"s in the low 11'sand high 10's, so i reached for the global fuel knob on the dash and pulled 6.5% out of the ECU's final pulse for fuel under ALL conditions and went WOT again... the car pulled cleanly at an AFR of 12.4 and there was no blowout at all I then went back to normal fueling and driving in traffic of course (i swear tuning anddriving is about like textand driving = just shouldn't do it )

I did a bunch of adjustments based on my observations while i was pumping the gas and then setup for home... Things were much better on less boost adn with the entire map leaned out a bit (Still low on timing and the J&S is setup extra sensitive for the time bein just in case) so although the pulls are no where near impressive i'm gaining confidence in at least going WOT without thinking it's just gonna blow another HG right away.. (has one of those big POPS and was worried because it was at the same 25-26psi and 5k + RPM so i swore i'd find coolant underthe hood but i didn't ) The L19's are holding

I"m gonna getthe logs i took on the way home imported into the home PC and see what i need to adjust in the fuel table based on those and then up the boost some more and work on the next ranges.. Usually I don'thave to start so much from scratch on the tune but to be honest i've changed the turbo to the HX40, went from 1000cc to 1600cc injectors, swapped from 1g IM to the cyclone IM and never finished the tune from chnging just one of those things before ading the next, then add in the HG failures and to be honest i've come to the conclusion that my entire fuel and spark curves are crap except for the cruising and highway/idle areas wher eit runs perfect becuase i've worked a lot on those areas.. But instead of minor tweaking i think i need to just keep timing WAY back, keep the J&S on it's toes and get my AFR's perfect through out the boost and RPM ranges before i even think aout adding any timing to this setup via the maps or putting the KS system back into a normal mode (i've got the J&S KS so sensitive that i'm regularly pulling 4-8* of timing in the areas where i'mdoing this tuning so my overall timing advance in the WOT range is probably really only about 6* peak torque and 10* peak RPM at 20psi (feels like a DOG!!)

But overall i think that now that the heads secure i'm realizing that this blowout is fromthe rich spike in that transition after the cyclnes valves open up (was swinging really rich into the high 10's and this is where that pop was coming in)So honestly i think the problem is solved, now it just needs tuned out, but we'll see as i proigress on the AFR's and start to give it some timing back..at least i'm not lifting th heads on the "gumby" brand head-studs now... after seeing them it made sense as to why the gaskets were so willikng to let go... it was almostlike i was re-using a set of torque to yield head bolts and expectingthem to hold (NEXT i need a new PC keyboard. each key picks certain times it will skip strikes no matter what, and sometime a key stamps out the letter next to it..not to mention the broken space bar arggghh..>@!!!!)

I know for a fact i need plugs and wires at this point, i just can't afford the wires right now but by the end of the month 9i should have some..plugs i'll get tomorrow if i remember and hjave timeto messwith the car

 

[94awdcoupe]

spark blow out is often caused by water escaping past head gasket during slight head lift. 16 at peak torque seems high to me. timing should ramp 6-12 degrees from 4000-8000 rpm depending on setup
I would try 10 rising to 18. bet your misfire and blown gaskets go byby.

 

[1983gsp]

Try a non projected br8es and gap it @ .024 I was having issues and they cleared up @ 27psi on my hx40 running 18* on a mix of 93 and 110.

 

[awddsm95]

spark blow out is often caused by water escaping past head gasket during slight head lift. 16 at peak torque seems high to me. timing should ramp 6-12 degrees from 4000-8000 rpm depending on setup
I would try 10 rising to 18. bet your misfire and blown gaskets go byby.

I concur....

 

[turboglenn]

About the timing, right now i am running really really low timing (10* ramping to 15* @ 20psi) and there's no difference in the behaviur of the engine except if feels a LOT slower.. the blow out was still there untill i found the rich spot where the manifold transitions from the long runners into opening the short ones.. i dialed out 6.5% fuel globally and pulled clean all the way through, so now i'm working on re-mapping everything.. The problem ended up being a set of stretched standard ARP's and i'm sure the cylinderpressures that resulted from my timing map helped make this problem show it's face. I'm thinking the studs stretched while i was replacing the valves after a t-belt failure i had a few months ago

As mentioned above, I made a LOT of changes to the engine without fully ever getting to tune teh fuel maps properly for one part before i was already putting on the next part..I switched from a 67mm turbo that spooled in the 5k + range to an hx35/40 hybrid i made that spools 19psi by 3600rpm, then i swapped from 1000's to 1600's and after the first gasket blew, I swapped on a completely differently behaving manifold (cyclone intake mani) which threw the AFR's way off everywhere in the mid-range from 4000 to about 5300 RPM (way rich) which is why it would pop at about 5k and then pull cleanly the rest of the way even though the tune was less than ideal.

Honestly tuning to "avoid knock" at spool and then trying to feed as much advance as you can by redline is the completely wrong aproach to tuning.... The correct way to tune is to look for and tune to MBT on a load bearing dyno (this means you're going for the most adance you can get right at the peak spool up of your turbo) then you only advance by "whats needed" to keep the flame front occuring in time for peak cylinder pressure to occur roughly 16* ATDC.

Last time i had access to a load bearing dyno was back when i built this engine and was tuning the pump gas maps.. at that time I found 14* to be optimal for MY ENGINE on pump gas, so working off those numbers as my general target, even if i have to be a little below it at peak spool, is still better than just saying "oh, person B runs 6* so that's what best for me"..that's not correct, whats best for me is what ever adance i make the most power at and beyond get dimishing returns. Plus i'm on e85 so if anything i'd want more advance now which is wherer the 16* base came from and i use to run much much more on ethoanol (i was hitting anywhere from 20-24* in the begining on the 57 trim and E85


And like i said, i've been running maps this agressive not only on e85 but on pump gas as well (my 57 trim pump gas tune was 14* timing at spool and 16* by redline) so i doubt it would start plagueing me with problems only in the last 2 months after being run this way for 11+ years.



I apreciate everyones help and input, i really do, but every engine will be different on what it likes for timing to an extent, but I will keep tuning the way i've been taught by many profesionals at the tuning seminars i've attended for companies like Haltech, AEM EMS training, and ACCEL EMIC training for their systems.. I wish i could convince people via the 'net but that's not happening, and I know there's many here that know the correct method for tuning the timing curve as i've seen them post about it. Only thing i can say is anyone is welcome to come take a ride in my car, look at my timing maps and watch my J&S knock system and see how much better is is to have a flat (example) 15* of timing though out the curve compared to starting at 10* and trying to feed in another 10degrees for 20* peak advance by redline, and it's not that one timing is better than the other, it's that you want to be as close to MBT as possible through the entire rev range only advancing by what's required to keep up with increasing piston speeds..

If your car makes MBT at 14* BTDC then starting a little lower to avoid knock is fine, but there's little to nothing to be gained by trying to ramp the timing past what it needs to keep up with piston speed by redline, which is usually about 5* or less.. IF you google "timing attack rate" you'll see that trying to feed in the most timing you can by redline is more likely to induce knock and won't make much, if any more power than if you would have just lefft the timing at the base 14* through out the rev range

 

[MY1GDSM]

Honestly tuning to "avoid knock" at spool and then trying to feed as much advance as you can by redline is the completely wrong aproach to tuning....

I concur

 

[94awdcoupe]

I honestly dont see any good tuners using a flat timing curve.
piston speeds at 8000rpm are double what they are at 4000rpm. you need a lot more than 5 degrees ramp to give the fuel same amount of time to reach MBT,

 

[turboglenn]

I honestly dont see any good tuners using a flat timing curve.
piston speeds at 8000rpm are double what they are at 4000rpm. you need a lot more than 5 degrees ramp to give the fuel same amount of time to reach MBT,

Got any examples of profesional tunes? I can send you or post a screen shot of timing curves done by austrailias big name "the hitman" as he doesn't mind sharing certain maps and those i can post up

Anyway.. piston speeds may be nearly double but when i loaded the car down and hunted for MBT then went up through the RPM's dialing it in i didn't gain as much power as i did risk when setting the timing any higher than i have it.. so no matter how many degrees i can add from onset of boost till redline i'm only adding what's safe and keeps the power up.. You don't have to run my tunes and surely don't have to like them, but i've been at this long enough to have worked on many more cars than just DSM's and i can garauntee you that you don't see timing curves done this way anywhere besides the DSM and STi worlds where it's just a modification of wha tthe stock ECU is doing which is meant for longevity and keeping warranty claims minimal and NOT for making the best HP curve

well,goptta go to dinner cat6ch ya'll later

 

[beansblacktsi]

I may be wrong, but I just looked up the torque specs on the 7 bolt studs from ARP with moly the other day, and they stated 86. I also read most guys who put em at 100 dont reuse them due to bolt stretch. So maybe your bolt stretch arised from the over torquing. Unless my torque specs I looked up are wrong or differ between 11mm and 12mm.

I was also going to say you should go out to your car tonight and take a look at the wires in the dark to see if there's any shorts going on. Beans is running BPR6ES @ .028" @ 35ish psi on his HX40 last time I checked.

wrong, I have always ran the 7s at about .024 but I started fighting misfires a month ago and tried gapping them down to .018 and ever since then I have had zero issues.