1dirtyZ

iTrader: (1)

i'm using tr-6 gapped at 35 thou. i'm going to call a shop here that's very reputable when it comes to injectors, i'll se what they will charge to flow match my 50lb svo's. ( anyone know roughly how much it costs to clean and flow injectors?).

30thta436

iTrader: (10)

I think you went lean on that cylinder and detonated, raising the heads and damaging the gasket.. then the combustion just ate away at the head. For some reason the #7 cylinder is usually the cylinder that detonates and the piston breaks. I have seen it several times. I think a loss of fuel pressure may cause the #7 injector to starve first.. Just a possibility.

<small>[ November 24, 2002, 10:21 PM: Message edited by: 30thta436 ]</small>

MelloYellow

Cool. Side Note.. am ordering 50# Delphi's from PTE tommorrow.

What is your pump setup? Any fuel pressure dips? Head Unit/Pulley size? RWHP?

1dirtyZ

iTrader: (1)

i have a walbro intank 225 pump and an inline aeromotive one. there was a slight dip in pressure on the old intank pump but now with the walbro dips are a thing of the past!
i'm using the ati d1sc head unit and the crank pulley is 8.1 inches in dia. and the blower has the 3.7" pulley ( 8 rib). the blower is just below max impeller speed right now.

30thta436

iTrader: (10)

Have you dynoed with a wide band. You may be running lean up high. What tunning do you have:?

1dirtyZ

iTrader: (1)

i did dyno with a wide band, it was set about 12.3:1 and i actually richened it a bit too after that.

Phate

iTrader: (2)

12.3 is a little too lean for a boosted setup. I think that the FI guys would all agree that about 11.7 is the leanest that they would want to go.

Just FYI. Good luck getting your setup back together ASAP.

Scott

MelloYellow

How much rwhp you putting down?
What kinda MAF Flow #'s are you seeing?

Ya, I'd richen up for safety a bit more. 11:1 very fat and safe. 11.5:1 is the leanest I'd go. Often you are .5 leaner on the road than on a dynojet. On the road 12.3:1 dyno could've been 12.8:1 street.

1dirtyZ

iTrader: (1)

mello, you got mail.
for some reason i forgot how the A/F ratio is different from dyno to street.
i guess i'll address that next dyno tune.

Reckless

iTrader: (9)

Well I did the exact same thing a few times when I first ran the metal gaskets. Turned out to be insufficient torque on the heads. I don't know what torque you used, but I'd go at least 80 foot-pounds with those gaskets to ensure a good seal.

There is a chance you didn't go lean. If coolant was seaping from the water passages due to the head not sealing, then that could've nuked the gasket. Happened to me twice when boosting.

You will need to take the head to a machine shop and have it TIG'd (filled in) and then milled to clean it up.

Now you are seeing why I gave up on LS1 FI <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />

SJH

looked at the pics.
Yep hot gas notched.
It should have made a god awful exhaust noise.
We did the exact same thing once but needed to finish the race. Car was making a horrendous exhaust noise with a 1.5" chunk of gasket gone on the header side.
Still ran 11.0's with 7 cyls.
Track official came over and said the car " sounds bad"
We just told him it had a little header leak,lol

Hopefully they can repair that.
Block deck OK?

1dirtyZ

iTrader: (1)

thats exactly how it sounded!
should have the heads back tomorow. luckly the block surface was ok.

i'm just wondering what caused the leak? could it be insufficient head bolt tourque? or gasket faliure?

Reckless

iTrader: (9)

Look familiar? I did this twice before I decided to torque down my heads more. I was using the ARE hardened head bolts at the time, and fianlly torqued them to 90 pounds to get a good seal.

<img src="http://www.turbo-ws6.com/blowngasket.jpg" alt=" - " />

Now if you run lean, this can and will happen under boost:

Melted plugs:

<img src="http://www.turbo-ws6.com/badplug2.jpg" alt=" - " />

With forged pistons, they will heat up and swell rapidly causing severe scoring like this:

<img src="http://www.turbo-ws6.com/piston.jpg" alt=" - " />

<img src="http://www.turbo-ws6.com/scoredcylinder.jpg" alt=" - " />

And when the above happens, this usually happens also:

<img src="http://www.turbo-ws6.com/spunmains.jpg" alt=" - " />

Been through all that stuff a few times. So I sold my turbo kit. Just ran out of money and patience I guess <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />

MelloYellow

We slammed my head bolts down on the Cometic's at 100-110 ft/lbs I believe. Just an FYI. I don't want to get into a tq/yield debate. We should know my results with the .078 Cometic, stock pistons and head bolt technique in 6 weeks under 9psi. I'm back to the D1-SC. Ordering within a couple days.

Need time to pin my crank, install Super Damper, gears some other crap.

I was thinking about bore mismatch affect on squish with the 6.0L heads also if anyone wants to address:
https://ls1tech.com/ubb/ultimatebb.p...c;f=1;t=009248

Is a tighter .030 gap on TR6's worth anything when trying to control detonation?

<small>[ November 25, 2002, 05:06 PM: Message edited by: MelloYellow ]</small>

1dirtyZ

iTrader: (1)

well good news , my machinist told me he could repair the head, he also recomended that i change the plug ( tr-6) to something that doesn't portrude to much into the chamber. some thing like the champions ( C55CX or even C53CX) which don't portrude that much.

and as for you , reckless all i could say is OUCH!! <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />

2001WS6Vert

The good new is that the forged pistons did their job and saved you from more expense + labor.

SSHOTROD

iTrader: (5)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by MelloYellow:
<strong>We slammed my head bolts down on the Cometic's at 100-110 ft/lbs I believe. Just an FYI. I don't want to get into a tq/yield debate. We should know my results with the .078 Cometic, stock pistons and head bolt technique in 6 weeks under 9psi. I'm back to the D1-SC. Ordering within a couple days. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">becareful
1. torqued 100lbs custom bolts/pulled threads out of block
2. torqued 75lbs stock bolts/held fine until removing of the heads and then over stretched bolts pulled threads <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />

MelloYellow

Good disclaimer. My mech has done this hundreds of times on LS1's without problems, but don't follow my/his TQ specs. God knows what juju he uses to pull it off. He's done my heads on/off this way 4 times, no probs.