I knew this would happen so I'm not surprised. I think it's a combination of everything not nessicarly one thing but not sure.

2000 Firehawk, 6 speed, 3.90 gear

LS1 SBE, flycut pistons
862 'notch' TEA 5.3 1.5 heads, milled to 58cc, WS6 store .045 notch headgaskets, ARP head bolts
custom BTR cam, 234/24ish, can't remember, it's kinda rowdy

Huron speed APS twin kit w/ 5860 turbos at 13psi
E85

When I put the engine together a couple years ago I didn't have any plans going FI. Well I did.

When I bought theses heads a very long time ago, I didn't know about the notch heads or that TEA used to drop the intake valve .100 which obsolutely kills PTV. I had to flycut anyway so I had them milled to 58cc and flycut some more. I think they were milled .040-045 I used the WS6store notch head gaskets because of the price.

Long story short last week I lifted the heads, or one head, who knows, hit 3rd gear and it starts rolling white smoke. I get out of it and drive normally and it stops. I started watching the temp gauge cause I knew what was coming. Couple seconds later temp gauge shot up, turned the heater on full blast and in a few seconds temp gauge went down. Drove the car home 10 miles, never got into boost obviously and it runs just fine.

Lambda was .80 and timing was 14.5 degrees w/ 13psi on the gate, it spools up pretty much instantly and pulls like a ******* freight train. Car did 450 to the tire w/ a LS6 intake and it has a FAST 102/102 on it now. At 13psi i figure it has to be making at least 700hp but haven't got it on the dyno yet, I was going to wait till I put Holley EFI on it.

I love the car, love everything about it. The idle, exhaust note, turbo whoosh noises and pulls for ******* ever, peak power at 6800 and I shift around 7k.

I know I'm going to blow the OG LS1 up eventually, I fully expect that. When it goes I have a L33 going in it. But for now I want to keep the LS1 till I chuck a rod.

I'm trying to decide what I want to do. I've thought about everything from re tourqing the heads and dropping the boost to 8-10psi, putting a set of hand ported 243's on it with the ARP bolts or going studs and a better HG.

Now you are thinking just go studs. The only reason I haven't ordered them yet is because of the L33 and I think ARP bolts should hold 13psi. I don't know if it uses the same length bolts/studs as the LS1. I know that changed mid 2004 and I believe the L33 is a 2004. I don't want to buy studs for the LS1 only to turn around and have to buy another set for the L33 when I launch a LS1 piston into the atmosphere.

I "think" the main reason it lifted the heads is because the heads have been milled so much and the deck surface is thin. I also don't know how good the WS6store gaskets are either. I'm not blaming anyone else or parts. The blame is on me and I fully expected this to happen. I knew I should have turned the boost down some, but after feeling the car at 13psi...I just couldn't do it...

Any thoughts would be appreciated.

J

 

Head studs are for making BIG power. They will not crutch pushing water due to detonation. (They might for a little while, but not really). The Timing numbers that these engines need to do a full burn with modern combustion chambers is vastly different than all of the old school stuff tells you. That being said, I would at least pull the heads to check for flatness and use new gaskets before going nuts at the strip. Try the same everything, but 2 degrees less timing and see what you get.

 

You really think that 14.5 degrees at 13psi on E85 is too much timing?

 

Not an e 85 guy but that seems save , are you running a flex fuel sensor? If not Don't they reduce the e content in winter months ? Possible problem there ? Otherwise the previous advice sounds good , check flatness , replace gaskets and reduce timing or boost - get the L33 ready . Maybe swap it in while the ls1 still has resale value ?

 

Were you logging at the time ? Any chance the boost creeping up ?

 

When you put it like that no.

 

No flex fuel sensor right now. It was tuned to whatever the E content is, which this time of year is probably more like E70. There's really no power increase above E50 anyway regardless if it's E70, E85 or E98. especially at this low of power level. The big difference is the tune is going to be fueling.

Unfortunately no. I had left the passenger window down just a little the night before and it rained and got water into the USB cable end. I blew it out but HPTuners kept dropping out. FWIW, the dozen of logs I had made up to that point, the kpa line was rock solid and never went over 192kpa. However, about 20 minutes before this happened I developed an exhaust leak somewhere. I have no idea if an exhaust leak would cause it to overboost to the point it lifted the head.

When I asked that, it was a legitimate question. IMO it's not, hell I think most guys run that on pump gas.

 

You are correct with everything you said. However I was running 14.5 degrees of timing not 25.

 

You well known the answer to that....what did the plugs say? 😘
And remember your 14.5 degrees may not be 14.5 degrees if you've got anything other than a stock motor in there. You could really be running several degrees higher than that. Almost everyone on here whose actually put a timing light on their cammed motor has seem that commanded timing wasn't accurate.

Edit...@kfxguy and I have been chatting about boost and bolts/studs in another thread on here. I've seen 16 psi from stock TTY bolts on my setup which is similar to yours.

 

^^^ x100 Head lifted due to detonation. Sure, milled and reducing head deck integrity doesn't help but just means it can take much less detonation before bad things happen. Any idea what AFR was when failure occurred? Need to look at all variables that influence detonation.

 

FWIW, 0.8 Lambda on E85 is a touch lean. Everyone tunes E85 on the gas scale not realizing that it doesn't like that so much lol.

For example, 12.5:1 is normally considered the best for max power on Gasoline. Its a Lambda of 0.85.
For E85, this AFR is roughly 7:1, or .72 lambda.

Should always aim to have a richer AFR with E85 when using the gas scale. Some of the shady stuff we've done at the track while tuning cars with no IC is pretty nuts.
We're talking sub-10:1 AFR (gas scale) to combat the 350 degree IATs and it doesn't even act rich.

Edit: I found a link with a bit of info you can check out:
https://www.motortrend.com/how-to/wi...-oxygen-sensor

 

I should probably note that I run my cars pretty fat lol.
I run ~20-22 degrees of timing up top at ~13 PSI, but I ramp the timing up there based on dyno results to see the torque curve. I also run a nice fat 10.8:1 AFR, which only gets fatter as boost goes up.
My little junkyard 4.8 managed 9s on 9 PSI and I went 5.80s in the 1/8th on 15 PSI with a 1.4x 60 foot with a converter that was so tight it would drop 2200 or more RPM on shifts. Starts off slow, kicks like a mule.

 

I don't tune anything in AFR or the gas scale, it's too confusing with blended fuels and it's derived from Lambda anyway.

My commanded is .80 but was seeing .77-.78 in HPT and 11.3 on the WB gauge in the car. I bought the WB a long time ago before I knew about Lambda, Which ever Innovate gauge I have will only display AFR.

With IAT's in the 40's I felt it was safe, maybe I was wrong. If the IAT's were higher I would have fattened it up some.

I can tell you, starting out my actual was in the .70ish and it did not like it..at all, not with 40 degree IAT's.

 

And you have my respect getting anything boosted to live with 300+ degree IAT's.

**** makes me nervous just thinking about it. LOL.

 

14.5 degrees is good but is it really 14.5 ? Did you use a dead stop and make a timing tab and varify that. If not it can be anywhere . My lc9 was 5.5 degrees off.

 

Yeah I was seriously responding, 14 timing, e85, 13 psi, depending on AF and other factors like raceweight would be fine.

 

300 degrees isn't that bad. Some of the guys there are running IATs approaching 500 degrees but are spraying methanol everywhere. We're talking several injectors in intake piping.
I think people get too hung up on IATs. I cringe when I see someone say they're pulling timing on gasoline above 120 and 160 on E85, and I'm over here not pulling timing on gas until 180 lol.

 

It will be interesting to see what you find when you take it apart.
It could have a cracked sleeve. That’s happened in LS1’s.

Look at the plugs yet?

In my experience, re-torque and lower boost doesn’t work. I tried it.

 

Kind of hard to believe E85 and 13 PSI would hurt it, but cyl pressure could be high with the milled heads. I wonder how the plugs looked, and actual timing. I know someone in Florida, I think, had engine problems, thought they were getting E85 from the pump, when tested it was something like E20, you gotta test. There is a station near me, list it as E50-85, it tested 76, prob lower with winter blend.
On a Procharged engine I had, I once measured over 330 IAT's @18 PSI, I would guess a turbo would be higher?
Would be interesting to see his findings.

 

I've been though this before. Blew the gasket on the passenger side, cyl 4 or 6, i dont remember. It was due to crappy head gaskets. Changed to ls9 and never had a head gasket problem again. So far ive been running 18-20psi on pump gas consistently and has seen 22-24 on occasion. I run my afr 10.8-11.2 at that boost. over 20 and i like to see 10.8. I have arp bolts. The other night I was logging some slight know at 12 and 13 degrees timimg. I changed the washerfluid/meth nozzle from a 5gal per hour to a 10gph.
My guess is those gaskets just arent up to the task. Don't waste your time trying to retorque....toss those gaskets and get some ls9's. Don't think you'll be better off with the $200 fel pros either. Just get the LS9's. Brian tooley sells them cheaper....If you plan on going with big boost later, the stubs may be a better bet, but if you have stock pistons....Thats would be a waste of money at this point. I know that so far, mine holds 20-22 no problem on arp bolts....but i'm scared to go any higher....