ARP Head Stud Question.

[CajunKenny]

I am thinking of removing the stock head bolts (currently torqued to 70 lbs) one by one and replacing them with ARP Head Studs and torquing them to 90 lbs or so.

The car has 117k with the original engine that has never been apart. (except for repairs that I've done) Head has never been off.

Anyone ever done this or heard of any results from this being done?

Before everyone jumps on me about this question, I am aware of the "Right" way to do things in regards to MHG's, RA's, and all that. This idea crossed my mind today and I want to see who knows what out there.

I just want to know if anyone has done this and what the results were.

Thanks...

 

[HommerSimpson]

There is no corect answer.. because you can not 100% say the factory gasket is still good.. the problem with factory bolts is they streatch and after time wont hold proper tourque.. breaking the seal by loosing the bolts might do more damage then good.. but if gasket is good and i bet its not real good replacing with arps might prolong its life a tad more then just retorquing factory bolts..
now thats my opinun and im stickin to it :}

 

[jdub]

Actually Hommer, once the stock head bolts are taken up to 70 ft/lbs they will hold quite well. If you back them out to replace you *could* induce a failure. Personally, I wouldn't fix something that's not broke

 

[WhtMa71]

I know people do this all the time with Hondas(B-series engines) but they come with a MHG from the factory. If you're going to replace the bolts with studs you might as well just replace the HG while you're at it. I retorqued my headbolts to 72ftlbs and still blew the HG 2k miles later..Its just hard to get an accurate reading trying to retorque the stock bolts. I loosened them and the torqued them down but the bolts like to "skip,jump, hop, whatever" because they arent lubed and you just dont get an accurate reading. Thats my personal experience anyways..

 

[supraguy@aol]

Yeah, just wait for BHG.
It's the logical excuse for an upgrade anyway.

 

[p5150]

Leave it alone.

 

[Poodles]

You can't do it anyway as the stock headbolts only use half of the drilled/tapped hole into the block while the studs have to go in all the way.

20 years of junk at the bottom of the holes doesn't allow them to go in easy.

Also, do not overtighten the studs, torque to the spec from ARP...

 

[willtotheumm]

if it ain't broke don't fix it

tackle two birds with one stone when your hg goes.

 

[1992supraman]

if it ain't broke don't fix it

tackle two birds with one stone when your hg goes.

+1

 

[Kckazdude]

Leave it alone.

QFT!

 

[starscream5000]

Also, don't pull a number out of the air like 90 ft/lbs and decide that sounds good to torque them to. Torque them properly or don't do it at all. This may sound harsh, but you'd thank me later for that bit of advice

 

[CajunKenny]

Also, don't pull a number out of the air like 90 ft/lbs and decide that sounds good to torque them to. Torque them properly or don't do it at all. This may sound harsh, but you'd thank me later for that bit of advice

No offense taken there starscream. I did just pull numbers out of the air because I didn't have my ARP chart in front of me when I posted the thread.

Ok. Thanks guys. You all provided the info I wanted.

I love you guys man! :biglaugh:

 

[starscream5000]

Remember, make sure you torque the ARPs per the instructions for either Moly specs only, or motor oil specs (I suggest Moly as it comes with the ARPs and provides a more accurate torque rating).

 

[Poodles]

if it ain't broke don't fix it

tackle two birds with one stone when your hg goes.

Overheat = BHG and BHG = overheat

overheat = warped head and bigger maching shop charges to get it fixed.

Assuming the stock headgasket isn't "broken" is a matter of opinion. They where all broken when the rolled off the assembly line with a torque spec too low to load the fastener properly to put the proper loads on the HG to seal.

 

[p5150]

QFT!

"Quoted For Truth"

or

"Quit Fucking Talking"

?

 

[Kckazdude]

"Quoted For Truth"

Dont see how quit fucking talking could have applied to this thread.

 

[p5150]

Dont see how quit fucking talking could have applied to this thread.

I didnt either - but I didnt know that "quoted for truth" was even an option for "QFT" until I googled it. I need to get schooled up on the acronyms.

 

[jeffdemara]

I bought my 91 supra turbo back in december... and the owner said that the HG was recently done by a toyota dealership..

now i dont know if any of you would know this but, would toyota possibly replace the gasket with a stock one and torque it back to stock spec like they did back when they were made? or did they have a bunch come back with BHG's and were required to torque them to a higher spec when replaced?

I have 165-170 compression across all cylinders (cold!)
and i am considering doing a MHG upgrade with ARP hardware for my future goals (maybe 15psi with a 57 trim, nothing too huge), but not sure what to think with those kind of compression numbers and what the previous owner has told me?!

anybody ?