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Heads lifting under boost? or blown headgasket? x5

  • Thread starter Thread starter Yellow302
  • Start date Start date Dec 19, 2008

Yellow302

Member
Mar 2, 2003
789
2
19
NJ
Dec 19, 2008
#1
  • Dec 19, 2008
  • #1
So after 7 months of not having a car ive gotten it back together.

Now after driving around. My overflow tank is being filled and over flowing. This was after getting on the car hard a few times.

Im thinking boost is getting into my coolant system.

Luckly so far there is no water/oil mix nor am i burning anything that i can tell.

The car is still drivable in normal driving.

After doing a few searches it looks like the heads are lifting up under boost causing air or exhaust to get in there? Other than that it looks like a radiator cap issue.. i dont think so..

So the reason i didn't pull the heads off this engine was because it was fine for the 80k miles before i got it from the junkyard.

Any other possibilities?

If the heads are lifting under boost... what are my options.
 

TrueBlue95GT

Member
Sep 29, 2003
966
0
16
Connecticut
Dec 19, 2008
#2
  • Dec 19, 2008
  • #2
I seriously doubt the heads are lifting from the block with only 8lbs of boost. It's most likely a blown head gasket. while the car is running and before it is up to temp, open the radiator cap and watch for small bubbles.
 

Yellow302

Member
Mar 2, 2003
789
2
19
NJ
Dec 19, 2008
#3
  • Dec 19, 2008
  • #3
ill take a look, honestly i am done with modding my car, it has cost me nothing but time and money and it hasn't been right after 2 years, car afford the down time.

Now even with a new engine not 2 weeks and blow head gaskits... never using a blower again.
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Dec 21, 2008
#4
  • Dec 21, 2008
  • #4
Yup the head gaskets are blown, higher boost is pushing combustion pressure into the coolant system.

If you choose to go back with new head gaskets I would recommend ARP studs and Felpro 9333-PT1 head gaskets.

Wes

P.S. And a tune.
 

Yellow302

Member
Mar 2, 2003
789
2
19
NJ
Dec 21, 2008
#5
  • Dec 21, 2008
  • #5
Stanger007 said:
Yup the head gaskets are blown, higher boost is pushing combustion pressure into the coolant system.

If you choose to go back with new head gaskets I would recommend ARP studs and Felpro 9333-PT1 head gaskets.

Wes

P.S. And a tune.
Click to expand...

did studs and gaskets... 4 times... they never hold together... is there some break in period or something?
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Dec 21, 2008
#6
  • Dec 21, 2008
  • #6
That's where the tune part comes in. :-D

Wes

P.S. I'd shoot for 11.5:1 AFR and 16* timing to start.
P.P.S. Make sure your heads and block are flat as well.
 

Yellow302

Member
Mar 2, 2003
789
2
19
NJ
Dec 21, 2008
#7
  • Dec 21, 2008
  • #7
if im going this route again, cant i just o-ring the heads and be done with this?
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Dec 22, 2008
#8
  • Dec 22, 2008
  • #8
Yellow302 said:
if im going this route again, cant i just o-ring the heads and be done with this?
Click to expand...

Want to shoot me a copy of your MTF file? I'll look it over and see if anything looks strange.

Wes
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Dec 22, 2008
#9
  • Dec 22, 2008
  • #9
Do you have a way to see your fuel and spark during WOT?

Grady
 

Yellow302

Member
Mar 2, 2003
789
2
19
NJ
Dec 22, 2008
#10
  • Dec 22, 2008
  • #10
ill shoot you an e-mail soon, files are in my laptop not my pc.
 

Yellow302

Member
Mar 2, 2003
789
2
19
NJ
Dec 22, 2008
#11
  • Dec 22, 2008
  • #11
final5-0 said:
Do you have a way to see your fuel and spark during WOT?

Grady
Click to expand...

fuel yes, spark. no
 

OrangeMustangGt

Founding Member
Mar 7, 2002
1,976
0
36
Cape Cod, MA
Dec 22, 2008
#12
  • Dec 22, 2008
  • #12
make sure you are max 15 deg btdc advance and 11.5:1 to start at wot

NOW....

My combo that worked GREAT after changing 4 sets of headgaskets at 10 psi:

ARP studs...Top bolts torqued to 90 ftlb
bottom bolts torques to 85 ftlb

CLEAN CLEAN surfaces , then FELPRO MLS gaskets...Ive even gotten bad gas and A LARGE KNOCK and it still hasent let go....stockers would let go before you even heard anything.
 
S

speedytang

Founding Member
Jul 28, 1999
765
1
17
Marengo,Ohio,US
Dec 22, 2008
#13
  • Dec 22, 2008
  • #13
I would say if your having problem with 8psi and your keeping your timing under 21 degrees at WOT and have a large enough fuel pump then you are off on your tune and are detonating. I use cheap graphite head gaskets and run 14psi with 91+ octane. I would not O-ring anything since you are having problems at such a low boost because instead of changing head gaskets you will be replacing pistons.
 

ProKiller

Founding Member
Apr 26, 2002
3,064
15
78
PA
Dec 23, 2008
#14
  • Dec 23, 2008
  • #14
i would agree to not o-ring the block. you'll just keep the gasket in place and force the pressure to the next weakest link which in our blocks is the hypercrap pistons.

i'd go with either the fel-pro or cometic MLS gaskets and studs with 90 on the top and 85 on the bottom bolts. take the heads to a machine shop to verify 100% that they are flat.
 

legalize420

Active Member
May 21, 2005
1,541
1
37
South Florida
Dec 23, 2008
#15
  • Dec 23, 2008
  • #15
i would do a compression test before anything else. also check the thermostat. could just be a problem with the cooling system.
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
9,301
1,642
214
Acworth, GA
Dec 23, 2008
#16
  • Dec 23, 2008
  • #16
Yellow302 said:
if im going this route again, cant i just o-ring the heads and be done with this?
Click to expand...

Hell yeah, now you're on the right track. O-ring the heads and run Felpro factory replacement gaskets. I've blown one head gasket in 12 years with this setup. Best part is, it's $13/gasket. I know what you're thinking, yeah, I did blow a head gasket, but that's with aluminum heads, and 490/635 to the wheels. I honestly think my Felpro 1262 intake gaskets cost more than my head gaskets do.

Kurt
 

Yellow302

Member
Mar 2, 2003
789
2
19
NJ
Dec 24, 2008
#17
  • Dec 24, 2008
  • #17
legalize420 said:
i would do a compression test before anything else. also check the thermostat. could just be a problem with the cooling system.
Click to expand...

true, could be... im not burning anything or loosing coolant anymore
 
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