lifting heads?

S

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Ok so here is the deal. I posted the other day that I lifted a injector and came to the conclusion that I needed new hold downs as it was lifting other Injectors but resealing in the high tune, so I ordered new OE hold downs and bolts. if they don't work I will go with the SoCal ones. my other problem is that every time I put my tune in the high setting and do a extended pull say from 50 to 130mph I puke coolant and also intermintanly Lift the injectors, this engine is fresh to death less than a thousand miles decked block and heads so surface is very nice. ARP2000 studs and mahle black head gaskets, stock CR with finger oval pistons, BC rods and WCFAB S475 over stock with 45% over sticks and a 10MM cp3 and PPE mani and up pipes. Now this truck has very base tunes in it and no dyno time as of yet ( want to get this sorted first) I have a hard time believing the ARP or gaskets have fallen short for this combo. I only have a 60psi boost gauge and it will peg it pretty fast. With the cold weather (single digits) I know that the boost will increase a bit. do I really need to go to a 625 stud or oring the heads? with a stock valley unit under a 475 I can't believe it is making much over 700hp.
Looking for a bit of insight or suggestions
Could my timing be causing too much cylinder pressure?
I have no clue as to what max boost is I know that is a ridiculous thing to not know but I have not got my 100 psi gauge in yet.
It does not do this in any other tune but my big tune feels very strong.

Another note is the WCFAB coolant tank is small and have heard that the tanks are known to puke coolant if they are too full.... thoughts?
 
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2004LB7

2004LB7

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Can you fill in some additional information if you can:

Drive pressure, timing, pw,, head stud torque, where they re-torqued after heat cycles, etc.

May help others help you
 
S

SAC owner

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2004LB7 said:
Can you fill in some additional information if you can:

Drive pressure, timing, pw,, head stud torque, where they re-torqued after heat cycles, etc.

May help others help you
Click to expand...
I will fill in when i get off work!
 
Frankin_truck

Frankin_truck

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Put a pressure gauge in the cooling system. If your exceeding cap pressure (15psi) you could have a problem. If your coolant tank is too small it should puke out excessive coolant and pressure should level out but if pressure stay at 15psi or more all the time you have issues.
 
S

SAC owner

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2004LB7 said:
Can you fill in some additional information if you can:

Drive pressure, timing, pw,, head stud torque, where they re-torqued after heat cycles, etc.

May help others help you
Click to expand...
Ok sorry I do not have all of the info you need,I do however put the ARP studs at 125 in three steps and no re-torque and i have used these studs before I built the bottom end.
I am putting a drive pressure gauge on soon, ordering this week. And timing and PW not sure as I can not pull DSP tunes with my efi live.
 
S

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Ok I have some measurements from machining the heads and block I am going to put a grade D gasket set on. the deck was shaved .005 and the heads have .008 shaved over there life with proper valve recession preformed.

I am going to say with grade C gaskets and .013 total removed this it my problem with the heads and injectors moving


Any thoughts on this?
 
Fingers

Fingers

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What was your piston protrusion? Not that that is the issue.

What bothers me about your description is that once a head gasket pops, it stays popped, even at lower power.
 
S

SAC owner

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Fingers said:
What was your piston protrusion? Not that that is the issue.

What bothers me about your description is that once a head gasket pops, it stays popped, even at lower power.
Click to expand...


So I realize I am a idiot and did not check this but my machine shop did as I ask him to make sure all of the top end fit with grade C gaskets. he decked .005 off...

What worries me at this point is the heads, they were fine when I took it apart never had a problem before, I am wondering if the heads have a crack that shows only past a particular boost or pressure level.

Is it possible that cylinder pressures caused by tuning can cause this?
this would explain the injector lift as well?

Also I am still not ruling out the surge tank.

Going to strap it up to my buddy's dyno and doing a pressure test on the cooling system once I seal up the injectors ( got all new hold down's and hardware) don't really know how else it can be pushing coolant.
 
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Fingers

Fingers

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It is possible that you have a crack in the head. The ones that only open up when things get hot are rare. I have a flaw in mine that only opens up when it is bitter cold. Coolant level goes down ever so slightly when the truck sits in the cold. I don't lose a drop in the summer.

To answer the tuning question. Hell yea you can create STUPID chamber pressures with bad tuning. To answer that question, you need to get on the rollers at a place that can measure the chamber pressures.
 
S

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Fingers said:
It is possible that you have a crack in the head. The ones that only open up when things get hot are rare. I have a flaw in mine that only opens up when it is bitter cold. Coolant level goes down ever so slightly when the truck sits in the cold. I don't lose a drop in the summer.

To answer the tuning question. Hell yea you can create STUPID chamber pressures with bad tuning. To answer that question, you need to get on the rollers at a place that can measure the chamber pressures.
Click to expand...

I don't think it has bad tuning motor has no knock or ping under heavy load, not a lot of smoke pretty clean for the power.. danville is the only place I know that has cylinder pressure tools.
 
S

SAC owner

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.020 overbore looking back at pics and I see this... is it possible that the "fire ring"
is to close to the edge?

 
S

SAC owner

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I pulled the heads, it lifted for sure. Not really sure how but sending heads out to check them again install gm gaskets and try again... wonder if i should go with some 625 head studs this time around?
 
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