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ARP head/rod/main worth it?

MitsuDriver274

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Jan 20, 2004
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319
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Bellingham, WA
I'm in the process of putting together a new motor for my daily, and wanted to know if its honestly worth the money to upgrade to arp fasteners?
 

Barnes

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Feb 9, 2003
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Richland, WA
What power do you plan to make down the line?
 

CarRacer

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Shakopee, MN
Using arp headstuds is pretty much a no brainer. They're very similar to the own headstuds in price and are better for performance.

The mains and rods? I've never ran them. There's discussion on whether or not machine work is required in order to ensure the rod and main bearing journals are still in round after installing the studs. I'd have that work done if it was my motor but do some reading on it yourself.

If it's a daily, I'd stick with headstuds and call it a day.
 

MitsuDriver274

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Jan 20, 2004
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Bellingham, WA
From what I've read (and please correct me if i'm wrong), but running full arp fasteners (head/main/rod) makes the 4g good to 450(crank). I don't plan on running anything near that, but ~ 280whp would be nice I just want it to do that and be reliable (obviously how you drive the car effects life of the motor, I don't plan on raping this car)

In comparison my old rally car (#274) 1990 gsx made 218whp 246ft (that was with a 34mm restrictor)and made it through 2 seasons without any failures.

So far I've the cheapest source I know of is extremepsi at 180 for all of em, Does anyone know of a better site?
 
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broxma

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Nov 16, 2009
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San Antonio Tx
When you do the ARP rod studs, the rods have to be bored back to factory spec I've been told, as they deform the large end. I had this done when I recently built my motor but I have also heard it is not entirely needed.
There is a problem with the ARP Mains. They don't have an accommodation for the oil pick up. They are studs so unlike the factory bolts which have the smaller "Bolt" for the pick up to mount to, the ARP mains dont.
You don't even have to remove the head to replace the headstuds with ARP's so why not.

Head studs are a no brainer as said before.
Rods, I was building for 350+ so I figured it a good idea.
Mains, if they aren't deformed, probably not totally needed for anything less than 350-400. I did it as precaution.

/brox
 

4thStroke

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Oct 22, 2007
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I've been told by a builder before that mains are not recommended without a girdle. OEM mains seem to hold up fine to a lot of power.

For head studs, the standard studs aren't really any (if at all) better than OEM studs. If yours are dated and need to be replaced and you arent looking to build a high power motor for cheap, stands ARPs will suffice. Otherwise, OEM will do fine if yours are still good. The L19s are the studs you want if you want something significantly better than OEM/standard ARPs.
 

MitsuDriver274

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Bellingham, WA
So from the sound of it the main and rods aren't really necessary, also....if i'm going to run arp head studs would it be wise to run a cometic gasket? because I was under the impression that by running the arp head studs a higher head torque value may be obtained (as high as 80 ft lbs, I believe stock is 47) allowing for better clamping for a tighter seal that will hold more boost, how does the oem gasket react under more pressure?
 
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4thStroke

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I have a Mitsu MLS gasket with standard ARPs torqued to 100ft/lbs. No issues at all holding 32psi from a 3076R on E85.

I wouldn't bother with the Cometic gasket. They are too hit or miss. The Mitsu MLS gasket does well. If you want an even better head gasket, the Fel-Pro does even better, but costs around $200.
 

Barnes

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I'm with 4thstroke on this on. Hell, I say that if you have a set of stock head bolts that look nice, use those. At most get the standard ARP head studs with a stock head gasket and live happily ever after. Also, the stock head bolts are torqued way higher than 47. I forget the number but I think it is ~90ft-lbs.
 

MitsuDriver274

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Jan 20, 2004
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Your right on the stock torque it is higher. Well I got my bottom end together today, i'm still on the fence on what to do.
 

JSchleim18

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Oct 16, 2006
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Long Island, NY
Don't sweat the ARP mains or rod bolts. ARP headstuds are a good price for added insurance. If you're not boosting over 25 lbs, you *could* get away with a regular Mitsu composite headgasket. I would personally go with a Mitsu MLS headgasket and ARP headstuds.

I personally use ExtremePSI for purchases. Since I live a state away, I get parts next day via UPS Ground. They have some of the best pricing and I have had zero complaints so far.

Good luck with the build!
 

4thStroke

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Oct 22, 2007
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+1 for extremepsi. I've ordered a few times. Nothing has been dropped shipped/taken forever like some other places. I've never had to personally speak with anyone, either.
 

CarRacer

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Jun 28, 2007
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Shakopee, MN
If you're going the MLS route be sure to have the deck and head surfaces cleaned up by the machine shop. It's far less forgiving than a composite gasket and needs a good surface to ensure proper sealing.
 

I reused the stock head bolts and some cheapo gasket out of an eBay gasket set /ubbthreads/images/graemlins/banghead.gif Three miles later, blown headgasket mess. Never again will make the mistake of using a crappy headgasket or reusing headstuds. The headstuds are known to stretch. It's just not worth the pain in the ass, reusing head studs.
I bought ARP's, a commetic, and Viola, no more problems. If the commetic is properly installed, there should be no issues.
 

Barnes

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Feb 9, 2003
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I would bet all the money for the rest of my life your head gasket blew because the gasket was crappy, or you did something wrong. Not because of the head bolts. I reused the head bolts on a gal's GVR-4 I fixed in town about 2 years ago. Still running fine and this lady doesn't drive like a sissy either!

That being said, go ahead and get the ARP head studs to A)Give yourself a warm fuzzy and B)Cheap insurance
 

Muskrat

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Jun 13, 2004
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Lexington, KY
Aren't the stock head bolts torque to yeild?

In that case, while you COULD probably reuse them a few times, it's a much better idea of replace them.

Basically every time you retorque the bolt you'll be streching the threads further and further. Eventually it will fail, and there's not a whole lot telling you when that will happen.
 

Barnes

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Richland, WA
NO! The 6-bolt engine's head bolts are NOT torque to yield. The 7-bolt engine head bolts ARE torque to yield. You cannot reuse torque to yield head bolts. Hell, we need to find the page from the manual. I don't think it even says to get new head bolts unless a visual inspection shows them to be bad.
 

iceman69510

Turn Right Racing
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Michigan
I know this is nit-picking, but John loves picking nits, usually. So, here we go.

Torque to stretch (plastic region) are not really "torque to yield bolts". If you truly torqued them to yield, they ARE junk.

Mitsu does not require stretch bolts to be replaced every time. How can you plastigage anything? They have a measurement requirement. Check the manual. I have reused stretch head bolts before (non-turbo). That said, I also had a stretch rod bolt in a 7 bolt fail on me, so I replace those regularly now.

He is fully correct on 6 bolt bolts not being stretch bolts. /ubbthreads/images/graemlins/wink.gif
 

ApexHunter

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Apr 25, 2007
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Marysville, WA
Stock head bolt torque was originally spec'd at 69 by Mitsu, then later they changed spec to 80. There was a TSB.


I actually spoke with ARP yesterday regarding torque on the mains, rods, and HS. The following applies when you are using the moly lube.

Mains: Hand tight studs into block. Snug nuts to 5lb-ft then pull straight to 60lb-ft.
Rods: Snug nuts to 5lb-ft then pull straight to 40lb-ft.
H.S.: Hand tight studs into block. Take nuts to 80lb-ft in 3 equal steps.


I am using all 3 (mains, rods, H.S.) Probably overkill, but it just made sense at the time.

Now i'm kinda wishing i hadn't used the mains as they don't have a mount for the oil pickup. Probably nothing to worry about but it's just ironic because i wanted to use all them to add reliability.
 

4thStroke

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Oct 22, 2007
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Location
Vancouver, WA
So we are torquing to 80lb-ft in 3 steps of 26.66666666666666666666666666666666666666666666666666666?

/ubbthreads/images/graemlins/laugh.gif
 
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