Why doesn't HPT change GM s/c LD9 timing????

[killerjuice]

^^^well hot damn, now I am excited to get home and try this... I wonder if I can fly out as "sick"... not likely in my position

[SpdRcrZ]

I'm going to need in on this

[killerjuice]

hopefully next up on the list is spark dwell, oh please oh please.

[killerjuice]

or maybe something that is costing us lots of dyno time.. when I reflash (which takes almost 3 minutes) my car runs like crap for about 2-3 minutes after.. this makes it tough to get quick dyno runs in. Is there a table somewhere that needs to be reset or something that we can change to correct this???

It should take (3 min to burn) and be ready to go, maybe I am just not seeing which option to change or not change, any help would be great!

[IanB]

Mine also seems to need to "relearn" some stuff before running right, there's a dead spot in the TPS from 0-15% until it's revved through the dead spot a few times. WOT however seems fine right after a reflash.

[killerjuice]

chris or keith, is there anything we can do to "fix" that or stop that from happening?? that would be gold and I will stop asking for stuff till 2008, I promise

[Chris@HPTuners]

its probably fuel trims or idle relearning or something. Not sure if anything can be done about it.

[killerjuice]

Are you considering looking into this? I personally would be a really happy person if we could get this glitch worked out. (I understand it is our PCM not the tuner)

[Bill@HPTuners]

if its idle relearn theres not much you can do.

[redhotjamedjimi]

i agree on the idle relearn or on a custom exhaust raising the open loop vs .closed loop worked for me in cold weather.

Mostly cause when the o2 isnt warmed up it would starting trimming (and dying)til it went back to 0 or warmed up.

Also i used the VE increase to make it run decent in open loop because of my increased VE at idle with a large up-pipe and tb spacer.

[killerjuice]

One thing that I am curious about... that table for min timing VS RPM, is that before or after KR??? like if I am running a 20 degree advance and I get 6 degrees KR, will I see the min of 18 degree's.. or does that over power and make my car run 14 degrees advance?

[c24s/c]

I emailed support@...

I want the update toO!

[killerjuice]

well gentlmen, I am flying home today so I will be testing it either tonight around midnight or tomorrow after I put the new head gasket in... I look forward to posting positive results.

[killerjuice]

all my timing tables add up now, car still has issues, hopefully the thicker head gasket fixes that tomorrow, I will post arounf 6-7 pm with those results.

[Bill@HPTuners]

cool deal...BTW anyone looking for the update we should have the public version available very soon

[killerjuice]

I could make this really long or really short. But to keep it short because it is reallly late this is what is up. As you have read I have been having tonnes of issues and nothing seems to be helping. I have done everything short of replacing the engine. As a last stretch of hope I have went against every pro engine builder who I have talked to or emailed and increased my quench. I was running 0.022" before and about 0.025" is the minumum recommended. When I built the engine I didn't even know what "quench" was a word... well I tell you something interesting... I know what it means now ina HUGE way.

I ordered a larger head gasket, 0.074" thickness as opposed to the 0.030" that I had in the car. Expensive little touch at just over $180 and it was just a shot in the dark, something I had heard about and did some extensive research about. Everyone I talked to said, "it's a timing issue" or, "you can't run that much power out of that 4-cyl"... those answers get really old FAST. So I went against what they said, and went with the mean or average results from my research saying I should use about 0.035"-0.045" quench.. so I am a little thicker than that now.

I would assume from the pictures you are about to see that eagle rods and wiseco pistons stretch a minimum of 0.022" at exactly 5400rpm (religiously).. so onto the pictures:







so as you can see the pistons were just barely kissing the head; therefore, my quench was too tight... the pictures make the damage look much worse than it is on the pistons, so we are still using them in the car. I was replacing the head for other reason, so we installed a different head with the thicker head gasket. We added the stock GM s/c timing and the car runs perfect, revs to 6600rpm and stays there, way more power, no CEL, no missing, and we logged about 1.5-2.0 KR when we used to have 12+ degrees. So the issue us 100% fixed and I am going to call Brian at Walls Rod and custom tomorrow and hopefully I can go put high 200's or low 300's down with 10-14 psi with water meth on pump gas. Wish me luck, and post replies if you have any questions or comments.

This has been almost a year of trouble shooting and it has finally come to an end. Thanks for everyones support and helped :cheers

Garrett

[SpdRcrZ]

wow, that sucks!!!

I'm glad you figured it out, and got it running again. Its odd that these 'stretch' enough to hit the head...... was the block decked? Do the pistons extend above the block @ TDC? I just find it hard to believe that would be 'stretch'...... I know Tom is running almost the same combo (different brand pistons) but same head gasket.... hasnt had any issues with the pistons hitting the head (last time I seen that happen, the rod bearing was bad).

[killerjuice]

I emailed eagle, and they said anything tighter than 0.030" will likely hit. So it is right in line.