tweecer and spark issues

blksn955.o

Founding Member
Mar 15, 2002
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st.louis mo 314
Is it possible for a bad pip/stator to be off when they go bad? reason is I am getting a good amount of ping/dett. from conditions EVERYONE is telling me just should not be there.

I am fairly off on power as well for my mods as I have been .5 slower with the ported heads/ported gt40 lower setup than when I had the unported gt40 heads and ported stock lower. I have gone threw damn near EVERYTHING with little to no change in performance.

I am starting to think maybe the dizzy is just not working properly or something. It is set to 10* base but at WOT I have the tweecer setup to on 3 diff. tunes.

1. 30* total with fuel enrichment stock

2. 30* with fuel enrichment off

3. 33* with enrichment off

all at 12.8-12.9 A/F and all pinging like mad at the end of the 1/4.

It runs and has always run really well on the street with great driving but not at WOT I have been tracking and now have NO other ideas about WTF is up other than the Dizzy?
 
Wasnt able to datalog the passes, but from other logs the spark is the same as commanded. The A/F may be off, but it was running soft with the a/f checked the last time on a dyno so I dont think thats the issue. Everything in the logs shows good, and good drivabiity...just total crap WOT no matter what is done.

I am really out of ideas.

The spark values are/were from on the top row the last for boxes (like 2,500rpm+)
31 31 30 30
30 30 29 29


34 34 33 33
33 33 32 32
with the second to top row 1* less at ea cell.

since the log is picking it up as correct I am wondering if my PIP/hall effect is bad in the dizzy and either sending more than that to the eec since its bad (if its bad that is). I think I am going to replace the stock coil as well and go back the Fri the 29th. I am also going to swap back on the O/R H pipe as I guess it could be the crappy factory 4 cat also hurting...but other than those 3 things....honestly everything has been checked, double checked, replaced, :(
 
The only time I have seen ANY improvement has been last sept (05) when I made a very bare bones tune out of the t4m0 with only slopes roughly done with the 1.2x's method with no other changes to ANYTHING and it picked up like 3-4ths and 3-4mph.

I based that I made a j4j1 with very few changes on that with no change...nothing I do with the j4j1 seems to help WOT. But damn if the drivability is not awsome with the j4j1.

BTW-coolant temps in the logs have NEVER gone above 193* no matter how hard I got on it in the summer when I ran a log...so I want to rule out a HG issue.
 
I say forget everything except what you know to be true ...

Max Load @t WOT @ ??? RPM results in the Ping Thing.

Duplicate those conditions exactly on the road with CalCon capturing data to hard drive :D

If Ping reoccurs ...
you got hard data to fill in the missing pieces of the puzzle :nice:

When I had my self ported E7 combo ...
I ran 36 total advance @ 12.75 to 1.00 with 93 gas :)

Grady
 
I dunno if I can duplicat it as it was really pinging at the top of 4th...that is getting REALLY dangerous and expensive on the street. I am going to rebuild the dizzy and get a stock replacement coil (like 40$ total anyway and the stuff is 14yrs old with over 120k on them) and datalog the next session on the dyno drag and see though.

I am also wanting to pull the valve covers and just double check the rockers and see if a lifter might be collapsed(sp?). I never was able to check them as they were out of the car for 4-5mo so they were dry on the last re-install. I was thinking (big mistake) maybe a cyl. or two is not opening up enough and causing a lean condition from the valve not opening enough/letting the same fuel the rest are getting???

But yeah, I already made a BARE bones j4j1 and t4m0 to see whats up one with stock timing tables and one with 30*. Maybe I am having some kind of issue I am just not seeing with 55in' the BDLN and MBT tables?? Going to try and make one pass each and see if anything improves.

Other than that...honestly...I am 100% out of ideas on what to do. Low in the rpms it does NOT feel soft at all...just seems to be above 3-3,500rpms second will bet loose in the low rpms from a roll :shrug:
 
I would think the top of 3rd gear would place a great enough load on things to make the prob happen although the amount of time for it to happen would of course, be shorter.

You can raise octane, fatten it up, or kill some spark

Somehow or the other, you gotta duplicate the prob while gathering data to start the fixing process.

Think your wb might be giving false readings :shrug:

Grady
 
No wide band used on the 1/4 pulls, but in the past with dealing with this no gain has yet to be seen from changing A/F....it just seems no matter what is done with the tweecer nothing improves to even get me close to were it was much less the improvement over that I should be seeing. Thats why I think its someplace else.

Took off my upper intake and fuel was just all over the back runners and even "seeping" out the back gasket (upper to lower gasket)...trq'ed it to spec. so I dunno why. Checked the drivers side rockers/lifters and they are ok, going to pull the pass side and check that side for any lifter issues early this week. got the dizzy out and should have that together by Fri. along with a new coil and see:shrug:
 
I ran with it on and off (set stock and set to be = with rest of the function in the table) with absolutely no change.

The J4J1 tunes changes/tweecs ran were exactly this...
Maftransfer for 98gtmeter
high slope set to 26.5683
low slope set to 29.8334
breakpoint from T4M0
fan settings
high ECT1_on 196
----- ECT2_on 200
------ECToff 190

low ECToff 182
-----ECTon 188

All 55's in MBT and BRDLN table with Alt. and Base matching, look above for numbers but at MOST 34* and up high in rpms all were 1* less than the max timing. Ran as little as 30*

Fuel base table stablized was set to 12.82 commanded.

Thats it all the tune was, I actually GAINED 1/4 as timing went down but ALL pinged. One of the shop owners was VERY confused as to why with such low timing and rich A/F.

I really think something along the lines of the Dizzy/coil or a collapsed lifter (with the fuel all over the back of the intake---I mean RAW FUEL-- I think a few valves are opening late/closing early from a bad lifter maybe :shrug: . The dizzy and coil will be replaced anyway as really they both have 120k on them.
 
I think I solved it:bang: :owned: :chair: :doh:

I was going over some things and I am preaty sure I installed the dizzy at 10* on the HB, and then timed that to 10* base, instead of 0* on the HB then 10* base...so basicly 20* base:doh: :doh:

After sitting down and thinking about it...it explains ALOT:owned:

I checked my lifters anyway as I had it apart and they are fine at least, and going to replace the coil anyway and may do the dizzy too still its only 75$ and mine does have 120k+ on it.

Anyway, thanks for letting me vent and giving me support...thats why I like how its a hobby/toy I can take a step back and take the time to go over everything with no added stress of DD'ing it.
 
****UPDATE****

well went to this last Fri. Dyno Drag League thing (12/29) and with the dizzy re-set no ping. However, it only ran a VERY slight better time of 13.80 and 13.812 vs. the 13.90 with 40* timing and pinging.

I still have the factory 4 cat H pipe on, and I am thinking I may even have a clogged cat (possible it does have 110-115k on it) and its NOT helping either way. My uppers control arms seem to be DONE, I had to stop on my 3rd pass as the whole car just started pulling itself off the dyno from the horizontal movement (it was bad the 1st and 2nd pass but not near as bad as the 3rd).

I am begining to think that the J4J1 is just not working for WOT for me...maybe its a bad bin file but I have downloaded it at least 2 diff. times at this point. I have seen NIGHT and DAY diff. with a bare bones T4M0 tune (4 10ths and 3mph with 4-5* less spark/at the stock 25*). I plan on running the J4J1 tune that has been the best the next time I go and also run 2-3 diff. T4M0 based tunes and see if its just that.

I will HAVE to get some new upper and lower control arms before I go back though.

here is a pic for you looking needs :D
2196_11.jpg


BTW if anyone wants to see what this "indoor Dyno Drag League" is about here is a link.

pics
http://www.midcoastperformance.com/index.cfm?template=pa&pa_id=2196

Event coverage
http://www.midcoastperformance.com/index.cfm?template=news&news_id=2625