when should start looking at puting a hg on my car

brad horton

New Member
Oct 20, 2008
102
0
0
Alabama
when should i start looking at puting on a new gasket? i dont have any problems at this point. i have 87 turbo 7mgte with 148,xxx miles ct-57 turbo, intercooler piping and sperco knock off ic, 3inch down pipe with cut out. im running it at stock boost now but id like to put out 15 psi when i get my lexus mass air and 500 injectors. the only reasion im at stock boost is i am worried about blowing a head gasket. at what point do i have to have one?
 

black89t

boost'en down 101
Oct 27, 2007
951
0
0
36
humboldt, ca
if you have the money, down time availible, and fully understand whats involved then go for the mhg. i mean its not a guarentee but if you do run 15psi on a original hg chances are its going to blow. if you want to be on the safe side you change it out, but then you are going to have the motor all torn down and the temptation to just dump money into the motor is going to be HUGE. but as far as the damage if you just run 15psi and do blow it. things SHOULD be ok as long as you notice it and don't drive on it too long or let it get too hot.
 

brad horton

New Member
Oct 20, 2008
102
0
0
Alabama
i think ill buy everything when i get my w-2 back and do it when i can, if i where to blow it i think me and my roomate could do it in a weekend, might not be fun but we could do it. just a good metal head gasket and arp head studs and the other random gaskets? any thing else i should do while im in there? is it worth the money to spend the money and do cams while im in there?
 

NewWestSupras

SoupLvr
Mar 1, 2006
611
0
0
White Rock
Don't do anything except proper maintenance till a problem arises. Then open the motor and check everything. Go from there. I'd leave well enough alone...especially if there are no issues now. gl.
 

gtsfirefighter

SM Expert on White trash
Sep 26, 2006
2,965
1
36
55
Weatherford, Texas, United States
suprahooked;1249346 said:
Torque the stock headgasket to 72 ft lbs and you should be fine for a while.

I would not advise that. If I were you, I'd go ahead and replace it. I'd bet money it's already on the brink.

I bought my 91 last Aug with 132k miles. It was a garage kept, one owner, adult female driven, properly maintained Supra. Here is the HG I had to replace right after I bought it. Only symptom was it was very slowly pushing coolant out of the reservoir. It never boiled over or ran bad.


p1249512_1.jpg


Waiting for it to blow will greatly increase your risk of getting coolant in the oil and then you'll get rod knock.
Either do an OEM replacement and torque to 72ft/lbs or if you just absolutely have to have a MHG, you'll need to pull the engine to have the machine work done, in which case, you should just go ahead and have it rebuilt.
I did an OEM replacement and it running great.
 

WhtMa71

D0 W3RK
Apr 24, 2007
1,813
0
36
Macon, GA
Just check your coolant and oil religiously! If coolant starts disappearing and/or your oil starts turning milky then do NOT drive your car anymore.

I did the retorque to 72 when I stuck my JDM engine in at the HG only lasted 2500 miles. It's been going strong for over 6k miles at 10-12 psi since I installed a new OEM HG and ARP studs.
 

877m

New Member
Feb 10, 2009
65
0
0
Lewiston, NY
well i rebuilt a few 7 m motors including my own personal one and let me tell ya if u want power and to run high boost u need a metal had gasket and don go buy some cheap ebay one buy a nice hks. and while you got it apart of are having it done i would get the head shave and the block machined and for 100percent buy arp head studs it will save u alot of trouble when u start building your motor
 

brad horton

New Member
Oct 20, 2008
102
0
0
Alabama
gtsfirefighter;1249512 said:
I bought my 91 last Aug with 132k miles. It was a garage kept, one owner, adult female driven, properly maintained Supra. Here is the HG I had to replace right after I bought it. Only symptom was it was very slowly pushing coolant out of the reservoir. It never boiled over or ran bad.

Waiting for it to blow will greatly increase your risk of getting coolant in the oil and then you'll get rod knock.
Either do an OEM replacement and torque to 72ft/lbs or if you just absolutely have to have a MHG, you'll need to pull the engine to have the machine work done, in which case, you should just go ahead and have it rebuilt.
I did an OEM replacement and it running great.

mine is a 2 owner car but the 2nd owner had it for a month or two, the first owner was a female and she keep up the maintenance (not the body) and i have owned my car sence the speed i had to top it off twice but also had the running water sound in my dash that i fixed by putting my car on hill with the cap off the radiator. I had to top it off then and when i first got the car it was a little low. So far i don't have a coolant in my oil its nice and black. i just lost a 351w to milky oil and i lost a 318 about 2 years ago. im only planing on running 16 pounds when im done with the car. while a oem replacement hold?
 
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queenskid926

Tires yeling @ every Lite
Jul 27, 2007
1,112
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36
New York City
www.myspace.com
WhtMa71;1249537 said:
Just check your coolant and oil religiously! If coolant starts disappearing and/or your oil starts turning milky then do NOT drive your car anymore.

I did the retorque to 72 when I stuck my JDM engine in at the HG only lasted 2500 miles. It's been going strong for over 6k miles at 10-12 psi since I installed a new OEM HG and ARP studs.



i did a retrq and pinch the heafgasket on the retrq lol 0 miles on that,


again if you want to do it in a weekend. get a new stock headgasket, some arp bolts and trq them down per spec.


some say stock hg with arp hardware will hold till 425.

it all depends on the tune tho, detonation will kill any headgasket
 

AjWit

Boostin without Boost.
Jan 31, 2009
92
0
0
Pittsburgh, PA
Would someone be so kind as to tell me everything that i need or should replace while doing a HG.

-HG
-ARP Head Studs
-Valve Cover gasket
-Timing Belt
-Water Pump

i know there's more, a little help please...
 

brad horton

New Member
Oct 20, 2008
102
0
0
Alabama
when i worked at advance auto parts they offered a gasket kit for the head gasket and it was evering u need to do a stock hg job, then you would need arp head studs, thats saying u did not warp a head
 

AjWit

Boostin without Boost.
Jan 31, 2009
92
0
0
Pittsburgh, PA
im buying a supra parts car, 89 with 7MGTE and like 101k original miles, engine cranks but the lack of a working fuel pump is why it wont start. im thinking about taking the head off that and see which one is better and use the better one on my current car.
 

877m

New Member
Feb 10, 2009
65
0
0
Lewiston, NY
u should go with a mks mhg its a little bit more but the last for ever and can take a beating its not worth it to put a stock one on to jus have to change it