Thread: Lifting Heads

has anyone on this forum personally lifted their heads from too much hp, if so how much power were you making, what turbo at what psi and what headbolts, if stock how many miles, were they installed new or reused ect.

Only head lifting issues we ran into was when we were using the old style ARP head bolts and that was at about 525 whp (25 psi more or less)

Yeah only lifting ive seen is with the wrong designed ARP's. I remember seeing people having issues with them as little as 400whp. Ive seen stock head bolts hold stronger than that.

I use Golden Eagle b16a headstuds and was roughly at 650whp at 35 lbs of boost, no head lift. Using a Cosworth headgasket as well.

I know JP took a stock ve to about 570+whp before it finally lifted the stock head/stock headbolts/stock gasket

Another thing to help and make sure there is no lift or when there may be slight lift that it wont be enough to break the gasket is to make sure your head and block surface are perfectly flat and clean as well as the front cover/oil pump being even with the block not sitting above. So basicly if you deck the block to make sure you deck the oil pump as well.

Stock DE/head bolts @ 24psi on a 35R lifted the head after about 20 dyno passes and a few Hard weekends at the local races. Last pass was 498whp.

Motor had 130k on it.

were u getting blow by at high boost, just oil no smoke out the breather, only at high boost i would say a 2 cap fulls

i have a stock low port and i had it up to about 26psi while tuning and its quite obvious i have to redo my crankcase ventilation system so far i havent lifted the heads but i am building a ve motor on the side and i am contemplating whether to go with mazworx head studs or good old oem, or redrill the block for gtir bolts

Blow By is due to rings... not headgasket issue..


Head lifting is usually indicated by an increase in temp and also white smoke out the exhaust only after a high RPM or high load run. Best way to tell which cylinder it is, after it is overheating, just remove spark plugs and you'll hear hissing or steam coming from the cylinder that has the spark plug removed. I'll agree if you are NA, just use NEW Factory headbolts.

Ya I don't see a reason for studs on an N/A motor. Nissan engineered the stock bolts to hold 220hp all day long on the DET block.

-G

i know that the blow by i am getting is not from lifting the head, i didnt suspect that i was lifting the heads, because i show no signs or issues with overheating ect. i just wanted to get an accurate idea at which point do the head bolts start to give to prepare for my future build. so far im up to 26psi on the stock motor with a hx40 in a bep housing on pump gas with methanol injection with about 115k miles.

the reason i am getting blow by is because my oil rings are giving out because of high cylinder pressures as well as an inproper crank case ventalation system. ( i am introducing no vacuum in to the crank case under load to help pull the pistons down and the charged air is simply forcing it self by the rings pressurizing the crank case, it only does it about 22-23 psi) so that problem i was expecting i only asked if he experienced that on his set up because he was running similar psi on a similar size turbo with a motor thats in similar condition

The way you worded your phrase just sounded odd that you were confused on the terms you wanted to use. I think you should use the term "oil blow by" It sounds better IMO. But if you're rings are giving out, do a leak down test, at around 30% leakage you'd get the oil blow by you are describing, which would mean engine is going out and no longer sealing. Also see if there is a repair shop that would not mind doing a bore scope in your cylinders to see the condition of the pistons, maybe some are melted. My old shop had 3 bore scopes with snap shot capable and also very high quality images, they are cheap too, saves 4 hrs to take a head apart when a valve might be bent. Look into doing that before you just try and band aid the engine by redoing your crank vent system. No need to assume things, get them checked out by a shop if you don't have the tools, $200 at a shop to tell you "no your engine is fine, no need to spend $2K on a rebuild is worth it IMO. Beats spending $400 on the tools your might only use once. Something to think about.

The leak down test is a great idea, i might do that, i dont really care to save this motor, its only a de, i am only pushing its limits to see how far i can go before it gives out. I already have all the parts and tools needed to build a motor minus head studs so i just wanted to know if stock head bolts would hold 35psi on a 69lb/hr turbo