I agree 100%, but, if the block and head were designed differently, it would not be as much of a problem.
I have a stock headgasket here I will gladly donate and ship for free if someone promises to go for 700hp with it. :naughty:
how much boost and hp CAN a stock hg take anyway
- Thread starter JDM 1JZ
- Start date
I have a stock headgasket here I will gladly donate and ship for free if someone promises to go for 700hp with it. :naughty:
at the shop i used to work at, we used aluminum spray paint made for bumpers on head gasket for aluminum heads with no issues...why, i dont know,, i just did what i was told...
Joel W. said:at the shop i used to work at, we used aluminum spray paint made for bumpers on head gasket for aluminum heads with no issues...why, i dont know,, i just did what i was told...
HAHAHAHA!!!:icon_bigg :icon_bigg :icon_bigg :icon_bigg
I heard chocolate sauce works too! It's gets all sticky when it's hot.
i know it sounds silly, but the guy i worked for had been turning wrenches for 50 yrs and this is what he recomended.. Granted this was usually done only when the head was not in need of re-surfacing.. in the 5 yrs i worked there, i never had one comeback that failed...
A though I just had:
Another problem is that Toyota tried to use the same headgasket for several M series engines to save money rather then redesign the 7M once they started turbocharging it. I know they never had turbocharging in mind when the M series was first develloped. They were just trying to milk the M series engines for cash until it became a warranty problem and that forced them to design the jz engines. Or, they knew the 7M was poorly designed and they develloped the JZ engines for their racing program? I'm not sure.
Another problem is that Toyota tried to use the same headgasket for several M series engines to save money rather then redesign the 7M once they started turbocharging it. I know they never had turbocharging in mind when the M series was first develloped. They were just trying to milk the M series engines for cash until it became a warranty problem and that forced them to design the jz engines. Or, they knew the 7M was poorly designed and they develloped the JZ engines for their racing program? I'm not sure.
Joel W. said:
Right, but 50 years ago you just used what was available to you at the time, now in modern society we have products that are made for specific applications. I have old machinists who have built 1500hp blown engines for years and years tell me a 50-60 ra is fine for a mhg and they don't understand why it needs to be so smooth for a 7m. 7m defies all engine building common logic.
lifesnotfair said:Poorly designed, and I was thinking of buying one.
Now I want a 1JZ again. =(
Don't be sad... :icon_bigg I am talking about the stock design, if you put a mhg on it and arp studs, you only have to worry about the rod knock! bwahaaaaaaa!!!! Resize the rods and grind and/or polish the crank and put arp rod bolts in to fix that issue. Shotpeening the rods is a good idea too. And KEEP OIL IN IT!!!
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i am building a good motor on the side, this motor only has to last me til next winter, i will push this things to some limits and see what its doing then since this just seems to be a big opinion argument. there is a local tuning shop i have full access to, i have access to a wideband system, etc etc etc... the cars unfortanately only got a 500 hp max set up so we'll see how it works for that... i just need to order a gasket set and some studs next week
i'll keep popping hg's until i figure out soemthing or til the motors done
i'll keep popping hg's until i figure out soemthing or til the motors done
The rumor is that the 7M was designed to blow it's head gasket from the factory. The theory is that the USA government was under pressure from the big domestic auto manufacturers to implement extra tariffs on Japanese auto imports, so that the domestic guys wouldn't have to compete on the same pricing structure. The underlying problem was that Japanese vehicles were bottom line better quality and more reliable, and cost the same amount of money at the dealership.
The theory goes on to suggest that the Japanese auto industry, in order to avoid paying extra money on imported cars to the USDM, offered to build in extra defects, explaining the obviously too low torque on the head bolts from the factory.
I'm sure there is no way to prove this one way or another, but it's an interesting thought nonetheless.
The theory goes on to suggest that the Japanese auto industry, in order to avoid paying extra money on imported cars to the USDM, offered to build in extra defects, explaining the obviously too low torque on the head bolts from the factory.
I'm sure there is no way to prove this one way or another, but it's an interesting thought nonetheless.
I agree w/Aaron, but i don't know, that seems pretty far-fetched... but it does kinda make sense...
N
NDBoost
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or until you have milled so much off the head it becomes virtually useless causing you to goto a junkyard spend even more money to have another head inspected, cleaned, and machined.JDM 1JZ said:
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@Grim:
Your just a paranoid old guy with insane theories of "The Man" :biglaugh: :naughty:
NDBoost said:
or when the bhg gets some coolant in the oil and all the bearings spin and a rod goes through the block.
Joel: I used the Aluminium Paint thing many many years ago on Iron motors with steel shim gaskets!
Grim: Do you have your Tin Foil Hat on ?
(Gotta stop those mind control waves)
Grim: Do you have your Tin Foil Hat on ?
(Gotta stop those mind control waves)
i have 2 spare motors and a few heads laying around etc and i said until the motors done so if its done i dont care haha
IJ: looking back now, it was 15-20 yrs ago... lol man time goes by fast, glad im not the only one lol..
welp we'll see im gonna push this and see what happens im real curious now, ive started 8 pages of debates, someone has to do something now and set the limit of how garbage or barable a regular hg is
JDM: If everything was perfect I can't see a stock gasket blowing from cylinder pressure.
Flat surfaces, good hardware correctly torqued, good tune, no detonation if any of these are missing it will die in seconds!
Flat surfaces, good hardware correctly torqued, good tune, no detonation if any of these are missing it will die in seconds!