Finally Dynoed....New Problem

Post by **240sxOwner** » Sat Jan 27, 2007 12:55 pm

Finally got the 240 dynoed after a year of "how much is that thing puttin to the ground?" I only got one run, because i had a surge of coolant burst out of the radiator cap right after the run. This is just barely hitting 10 psi

Max Power - 285 hpMax Torque - 267 tq

T4 turbo with V-trim compressor wheel. JE pistons, FMIC, Revhard Manifold, 3 in Exhaust, ARP head studs. 150,150,150,130 compression.

Anyone else have an idea as to why my coolant did this? Driving normally out of boost the car will run forever w/o overheating. I will post the dyno chart as soon as i can.

Post by **Swedish Mike** » Sat Jan 27, 2007 12:57 pm

240sxOwner wrote:Finally got the 240 dynoed after a year of "how much is that thing puttin to the ground?" I only got one run, because i had a surge of coolant burst out of the radiator cap right after the run. This is just barely hitting 10 psi

Max Power - 285 hpMax Torque - 267 tq

T4 turbo with V-trim compressor wheel. JE pistons, FMIC, Revhard Manifold, 3 in Exhaust, ARP head studs. 150,150,150,130 compression.

Anyone else have an idea as to why my coolant did this? Driving normally out of boost the car will run forever w/o overheating. I will post the dyno chart as soon as i can.

Head gasket? Compression leaking out in the cooling system can cause that.

Post by **C-Kwik** » Sat Jan 27, 2007 1:03 pm

^^^ Sounds like this could be it. I'd do a leakdown test to confirm.

Post by **Swedish Mike** » Sat Jan 27, 2007 1:05 pm

C-Kwik wrote:^^^ Sounds like this could be it. I'd do a leakdown test to confirm.

The hard part is that they sometimes only leak at max boost (for a start). Hard to test.

Post by **240sxOwner** » Sat Jan 27, 2007 1:05 pm

im afraid it is...that is what my original thought was..

Post by **KATwo40** » Sat Jan 27, 2007 1:41 pm

Cometic headgasket?

Post by **240sxOwner** » Sat Jan 27, 2007 4:54 pm

fel-pro....cometic to come...

any sponsors have a good deal on them?

Post by **eazye2000** » Sat Jan 27, 2007 6:13 pm

240sxOwner wrote:fel-pro....cometic to come...

any sponsors have a good deal on them?

How is $69.20 sounding to you?

http://www.amsperformance.com/...d=153

Post by **Florida240sx** » Sat Jan 27, 2007 6:44 pm

What did you torque the arp head studs to?

Post by **240sxOwner** » Sun Jan 28, 2007 6:05 am

I torqued them down to the max amount the specs say to for the stock bolts...That is what i was told to do by someone else on here.

Post by **boznuttz** » Sun Jan 28, 2007 6:51 am

Did you follow the fsm while tourqing? Also, a few days ago my friends removed the head of his 89 sohc and......the coolant galleries and passages were completely clogged.

Post by **nissanfanatic** » Sun Jan 28, 2007 7:49 am

Your problem isn't HG strength.. There is another problem with your setup.

Post by **fiznat** » Sun Jan 28, 2007 8:40 am

Think simple first. Your coolant will shoot out if the cap wasnt screwed on tight enough. Is it possible you didnt put it on right, or maybe it got bumped? If this has never happened before and it is not happening anymore, I would really look for the cheap/easy fixes first. 9 times out of 10 the solution is something really stupid.

Also if you go with a cometic MLS headgasket, I would also consider resurfacing the block (decking) and the head. MLS headgaskets dont conform as much to the surface of the block and generally requre a VERY flat surface in order to seal correctly.

Post by **WDRacing** » Sun Jan 28, 2007 10:44 am

Word ^^ Copper FTW

Post by **240sxOwner** » Sun Jan 28, 2007 2:01 pm

i thought it was a cap problem...so i tried 4 different ones and they all do the same. This only started happening after i blew and intercoolr pipe at 12psi one night. Later down the road i will be rebuilding the motor completely...should i just get another fel-pro for now?

I guess the numbers are pretty average or else i would have gotten a comment on them...lol Thanks for the help, keep it coming

Post by **masterteque** » Sun Jan 28, 2007 2:03 pm

Sounds like a blown head gasket......

Post by **fiznat** » Sun Jan 28, 2007 5:23 pm

Do you have a way of continuously monitoring your coolant temperatures? ...I mean, something other than the dummy gauge in the cluster. If you have a blown HG you will see the temperature shoot right up very quickly as you get into boost.

If it is still happening, blown HG is probably the most likely reason. Do you have coolant in your oil, or oil in your coolant? Is your car smoking at all? Coolant will burn white and the smoke has a sweetish smell to it.

Post by **240sxOwner** » Sun Jan 28, 2007 6:06 pm

no mixing of fluids......no smoke....car runs like at absolute champ.

My other temp gauge just broke so dummy is all i have at the moment

Post by **KATwo40** » Sun Jan 28, 2007 6:20 pm

If you know of a shop with a 5 gas analyzer (should be pretty much any shop that does vehicle inspections in your state), you can figure this out pretty easily.

Stick a hose over the radiator neck (radiator cap off), about 2ft long, pointing straight up. Run the car, stick the sniffer down in the hose and see if you get:

HydrocarbonsCO2CO

That'll tell ya' pretty quickly.

I'm bettin' you have a leaking headgasket, given that odd cylinder compression number. I'd just get another Fel-Pro gasket.

Post by **TheOne** » Sun Jan 28, 2007 7:59 pm

compression numbers aren't right, JE pistons ~8.8-8.5 compression ratio?(wondering due to rather lower compression numbers, those seem fine cept for #4)

also there isn't supposed to be more than 14psi difference between pistons as far as compression goes, sounds like you are shottin boost out of piston 4, and its goin into the coolant passage.

also don't you have to re-torque arp studs after so many miles?

Post by **240sxOwner** » Mon Jan 29, 2007 12:52 pm

if you are supposed to retorque, i wasn't notified..lol The 4th cylinder has been at 130 for 8 months of track use and beating up on it and i never had this problem until i blew the intercooler pipe.

After a normal drive when the car heats up, you can hear the hissing from the radiator cap, but every cap i have tried does the same thing. Is the coolant system getting pressurized some other way? Is it possible?

Post by **nissanfanatic** » Mon Jan 29, 2007 1:06 pm

probably a really good sized consistent headgakset leak...

Post by **TheOne** » Mon Jan 29, 2007 6:40 pm

240sxOwner wrote:After a normal drive when the car heats up, you can hear the hissing from the radiator cap, but every cap i have tried does the same thing. Is the coolant system getting pressurized some other way? Is it possible?

too much boost could try to escape to weak spots on the headgasket and goin into the coolant, tho the hissin is prolly the overheated water/coolant turnin into gas & maybe pressurizing the system.

i was told about the retorquring on V8's(friend has an lt1, has arp head studs and he's supposed to retorque'em after a warmup/cool down on the first start or so), probably the same for the ka as they used the same material and what not.

Post by **WDRacing** » Tue Jan 30, 2007 9:17 am

I posted this in another thread about ARP hardware. Always retorque or torque check things like the head and what not. If its accessable, then check it. Everything stretches, so a retorque is almost always done on my cars.

Ive been a helicopter crew chief for 13 years. We retorque or torque check everything.

If I were you, I'd retorque the head right now. Just to see what happens. Worst case scenerio, nothing changes. It only takes about an hour of time.

Finally Dynoed....New Problem

Finally Dynoed....New Problem

Re: Finally Dynoed....New Problem (240sxOwner)

Re: (C-Kwik)

Re: (240sxOwner)

Re: (240sxOwner)

Re: (240sxOwner)

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