Head lift on a SC @ 13.5psi ?
#63
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I'm still not 100% convinced we're all seeing headlift, at least those of us under 600whp. Hell, I've always got a little bit of coolant on the top of my APS overflow can after hard runs, and the level in that can is usually higher than I'd like to see, but until someone can show me trashed head gaskets, oil analysis proving coolant in the oil, or proof of stretched out head studs, I'm going to have to say that our motors are just running too hot under boost due to an inadequate cooling system.
Again, I'm only saying for those of us well under the 600whp mark. Over that, anything's possible I suppose.
Again, I'm only saying for those of us well under the 600whp mark. Over that, anything's possible I suppose.
Last edited by failsafe306; 04-19-2006 at 12:36 PM.
#64
Any one know where the temp sensor is , that the ECU reads ? If it's coming out of the motor or going into the motor ? If the sensor is located on the water coming out , I can log water temps and see how hot it runs when Im boosting . If the sensor is taking temps if the water going into the motor , it wouldnt do much good to log them
#65
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Originally Posted by booger
Any one know where the temp sensor is , that the ECU reads ? If it's coming out of the motor or going into the motor ? If the sensor is located on the water coming out , I can log water temps and see how hot it runs when Im boosting . If the sensor is taking temps if the water going into the motor , it wouldnt do much good to log them
#67
Originally Posted by failsafe306
I'm still not 100% convinced we're all seeing headlift, at least those of us under 600whp. Hell, I've always got a little bit of coolant on the top of my APS overflow can after hard runs, and the level in that can is usually higher than I'd like to see, but until someone can show me trashed head gaskets, oil analysis proving coolant in the oil, or proof of stretched out head studs, I'm going to have to say that our motors are just running too hot under boost due to an inadequate cooling system.
Again, I'm only saying for those of us well under the 600whp mark. Over that, anything's possible I suppose.
Again, I'm only saying for those of us well under the 600whp mark. Over that, anything's possible I suppose.
going to try bleeding it to see if this works out.my car has only done 500 miles since my aps tt install.
#68
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Is yours FULL, like literally overflowing, or just high enough to cause the sloshing of the coolant around to come out of the small hole in the top? Mine is doing the latter, it's not what I'd consider overflowing by any means. If yours is overflowing, you most likely have air in the system.
#69
I wonder if APS has experienced this. Cuz this is only been a problem since the install. Im sure they must have seen something like this.
Originally Posted by failsafe306
Is yours FULL, like literally overflowing, or just high enough to cause the sloshing of the coolant around to come out of the small hole in the top? Mine is doing the latter, it's not what I'd consider overflowing by any means. If yours is overflowing, you most likely have air in the system.
#70
Originally Posted by failsafe306
Is yours FULL, like literally overflowing, or just high enough to cause the sloshing of the coolant around to come out of the small hole in the top? Mine is doing the latter, it's not what I'd consider overflowing by any means. If yours is overflowing, you most likely have air in the system.
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ok.... when I said my radiator cap was bad.... I can actually see some coolant trapped in between the clear film on the nismo logo sticker... and right after I swapped the cap, it never happened again though. Never have the coolant overflow issue again and the overflow tank stays just slightly above the max. level mark (and sometimes it is just get a little bid lower).
but I did notice one thing before I swapped the cap, I would only have heater when I gave the engine some gas and as soon as I let go of the throttle, heater would be gone.... probably mine was the simple problem since my heater just didn't work over night (not gradually becoming colder).
cheers,
richie
but I did notice one thing before I swapped the cap, I would only have heater when I gave the engine some gas and as soon as I let go of the throttle, heater would be gone.... probably mine was the simple problem since my heater just didn't work over night (not gradually becoming colder).
cheers,
richie
#72
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Originally Posted by failsafe306
I'm still not 100% convinced we're all seeing headlift, at least those of us under 600whp. Hell, I've always got a little bit of coolant on the top of my APS overflow can after hard runs, and the level in that can is usually higher than I'd like to see, but until someone can show me trashed head gaskets, oil analysis proving coolant in the oil, or proof of stretched out head studs, I'm going to have to say that our motors are just running too hot under boost due to an inadequate cooling system.
Again, I'm only saying for those of us well under the 600whp mark. Over that, anything's possible I suppose.
Again, I'm only saying for those of us well under the 600whp mark. Over that, anything's possible I suppose.
i did have black residue in my coolant, but no milky oil...
#73
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Did you take your studs to your machine shop to be accurately measured to see if they're stretched out, by any chance? Not doubting your theory, just curious. I'd think if they were stretching, there would be tell-tale signs. It would be interesting to see the results.
#74
My350z
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sorry i didnt read everything here.
take out your thermostat and gut it out. i gutted out my thermo and filled half of my coolant with water and it runs 40 degrees F cooler all the time. i think everyone with FI should do this. the only downfall is that your car takes a bit longer to warm up.
much much safer cause i have heard of a few people overheating their cars...
take out your thermostat and gut it out. i gutted out my thermo and filled half of my coolant with water and it runs 40 degrees F cooler all the time. i think everyone with FI should do this. the only downfall is that your car takes a bit longer to warm up.
much much safer cause i have heard of a few people overheating their cars...
#76
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Originally Posted by failsafe306
Did you take your studs to your machine shop to be accurately measured to see if they're stretched out, by any chance? Not doubting your theory, just curious. I'd think if they were stretching, there would be tell-tale signs. It would be interesting to see the results.
a few of the other possibilities allowing head lift:
-head studs not being re-torqued (as recommended by ARP)--this is a very grueling procedure, as one would have to remove the timing cover and cams
-mating surfaces between block and heads are not redecked..therefore not sealing completely
-detonation dramatically affecting cylinder pressures and forcing the heads to lift- possibly pulling the studs slightly out of the aluminum threaded block
...a few possibilities
-head gaskets compressing and crushing
#77
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Originally Posted by 350zDCalb
-head studs not being re-torqued (as recommended by ARP)--this is a very grueling procedure, as one would have to remove the timing cover and cams
Last edited by Gman2004; 04-19-2006 at 08:40 PM.
#78
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Originally Posted by Gman2004
do you happen to check to see if yours needed to be re-torqued?
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Originally Posted by failsafe306
I suppose if detonation were bad enough, it could warp the mating surfaces, correct?
detonation is not the only answer here, there becomes a limitation of matter...the standard arp studs do provide a tremendous amount of clamping force between the heads and the block. Greater amounts of torque to the studs will decrease the instances of cylinder head lift, the choices are; stronger studs, steel inserts in the aluminum block, larger diameter studs...or all of the above.
GT motorsports claims that there are a few vq35's that are in a drag race platform making 1500+hp and do not have a hint of cylinder head lift issues (these motors are built with 14mm studs)