Sanctifier
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 Posted: Sat Jan 27, 2007 10:12 am Post subject: 4G63 TUNING: Compatible Upgrade Alternatives - #1. |
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4G63 TUNING: Compatible Upgrade Alternatives for cash-strapped 2NRs.
CONGRATULATIONS! Finally you've been able to afford your first 4G63 (or even an Evo.)
... but now you�re FLAT BROKE!  So what next... Basically your best choice now is to beg
or borrow a little more money to freshen up your "new" ticket to Adrenaline Heaven.
PREPERATION:
Pre-Installation: - Now is the time to find, buy and install the following:
| Quote: |  New Tools: ... For the DIY 2NR, borrow or buy a Metric Torque Wrench.
NB:...  usually states Evolution torque specifications in N.m. rather than kg.m. or kg.cm. |
| Quote: | | NEW MECHANIC: ... for the less experienced 2NR (for the time being.) |
If your trusted, "BESTist" mechanic doesn't find it necessary to use a torque wrench in
good condition for almost all nuts & bolts... Then scratch your head... TWICE
If he DOESN'T HAVE one at all and tightens con-rod bolts and cylinder head bolts
"by guess and by God!"... THEN FIND ANOTHER MECHANIC WHO HAS ONE
... AND USES IT TOGETHER WITH THE WORKSHOP MANUAL! (for OEM Torque Specifications.)
BTW beware of ANY Mechanic that tells you...
"I doin' this so for years! I accustomed to how the tension does feel!"
He is obviously better than all the engineers at combined ...
It is in your best interest to REPLACE your mechanic BEFORE major headaches occur! 
| Quote: | Maintenance Parts & Supplies:
Oil-pump, Water Pump, ALL Timing Belts, Fan belt, Spark Plugs, Synthetic Oil. |
How much cash did you "fork-out" for your engine? These keep it working well much longer
and give you piece of mind when you "stick your big foot on the accelerator pedal!" 
| Quote: | "Reliability Insurance" Parts:
ARP Connecting-rod Bolts, ARP Cylinder Head Studs.
OEM Cylinder Head Gasket, Sump Gasket, Rocker Cover Rubber Seal and Spark-plug Grommets. etc. |
How "gently" did the previous owner treat the engine? How old is it anyway?
How much did you fork-out for your engine?
These will "insure" that you keep it in one piece when you "up the boost."
WHY do you desperately need this second batch  Here's why...
BOOST: Higher boost levels demand "guaranteed" cylinder head sealing...
or your baby will "blow"... and not the "nice kind" either. 
Higher boost pressure also increases combustion temperature significantly and increases the
force acting on your reciprocating components... especially con-rod bolts.
| Quote: | NB. The con-rod bolts usually fail FIRST!
They usually STRETCH... BEND... and then SHEAR (snap into two pieces)... Bye, Bye 4G63! |
So upgrade OEM con-rod bolts to ARP bolts and OEM cylinder head bolts to ARP head studs.
NB---> ALWAYS "chase" (clean) cylinder block bolt holes with the correct "chasing tap" FIRST
...... (and blow out any shavings left too) before installing the ARP head studs.
NB---> ALWAYS use ARP Assembly Lube on studs... DO NOT USE OIL!
FOLLOW INSTRUCTIONS:
Screw in studs "hand tight." Follow torque instructions for head studs...
Use Stretch Gauge if available for con-rod bolts... failing which use good torque wrench.
| Quote: | I blew a head gasket on my 12.1 run last week. In researching why it may have gone out considering I had only 23-24 psi, 20-21 degrees of timing, and zero knock, I came to this conclusion.
Others have seen this as well. When putting this head on, I didnt have any of the ARP moly lube that you lube the threads with. According to ARP on dry new threads up to 95% of torque being applied is spent just overcoming the friction between the male and female threads. Since we cant use a stretch guage to set clamping pressure on the head gasket, we have to rely on ARP to do this testing for us and give us a corresponding torque value to set the studs to. Since the amout of friction and torque wasted in the threads varies significantly witht he lubricant used, you must use ARPs brand moly lube. They suggest torquing to 80 ft/lbs (I dont have the chart in front of me, but thats close.
Check the chart on ARPs website) on thier moly lube. In the case that you dont have any, use motor oil, and it has to be 10w30 (again, f=the type of lube will affect the amount of friction in the threads), and torque to 110 or so. Thats a BIG difference. I have seen a few people besides me recently use oil and lose the head gasket.
I found that you can get the ARP lube from summit. They dont advertise it, and a search on thier website didnt turn up anything. I went through ARPs catalog and found thier part numbers for it, plugged those into Summits Manufactures search, and found the stuff. Its about 7 bucks for a tube of it. Or 18 bucks for a can. It should be here tomorrow.
Also, ARP stresses that the studs have to be in the block hand tight. In my case some of them wouldnt go in by hand and I had to double nut the stud and drive it in. I took great care not to tighten the stud in the block. But still some of the nuts came loose, two adjacent ones in front of cylinder 1. I'm willing to bet thats where the gasket failure was. So I ordered the M12x1.25 chaseing tap from McMaster since the tap and die set I use doesnt have that size. Hopefully after chasing the threads with that tap the studs will go in loosely as they are supposed to.
Just for the info in case anyone is going to be using the ARP studs.
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My moly lube showed up today. The 6 dollar tube is pretty good sized I must say. Unfortunately, it came in the same box as Chads gay arse 5" tach, so I'm afraid to use it.
More interesting info from the tube. Torque is a variable (referring to the amount of tesile pressure it puts on the fastener) dependant on the amount of friction for the lubricant used. Motor oil as a lubricant will run away from heat and pressure, causing more friction and insufficient clamping loads that vary many hundred of pounds per square inch.
ARP moly provides the most consistent clamping loads without having to measure the exact elongation of every bolt (stretch technique). Able to withstand pressures to 500,000 psi, effective from 30-750f.
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You must own a 7 bolt motor. The manual is correct, but thats for the stock "torque to yeild" or "stretchy" bolts. They use bolts that will strech and put the proper clamping force on the head regardless of the torque value you use, as long as you go past some point.
But unfortunately just when you start to make some real power, they stretch a little more Plus they are not reusuable. Even if they are still within spec, I wouldnt use them.
If you go to www.arp-bolts.com you'll find a table that shows what torque to use.
I believe its 86 for moly, 109 for oil. But I thought the little instruction sheet that cam with mine said 90 and 120. Either way, we use the 12mm studs for 6 bolts, 190,000 psi. 11mm for 7 bolts.
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They all went in beautifully by hand. I highly recomend anyone doing anything with the head off spend the 10 bucks and get the tap! Torquing to 80 pounds with ARP moly lube (summit) was so much nicer than the abortion that is torquing to 110 with oil... I'll never go back
Its holding great so far, I've been up to 25 psi and 46 pounds per minute.
In contrast when it was leaking on the 16g I was only at 38-40 pounds. We'll see how it does when I raise the boost this week.
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But to answer the question... The whole purpose of stretchy bolts is to take the emphasis off torqueing properly or measuring stretch to determine clamping force. You can look it at it like drastically lowering the resolution of the changes you make. So if you are off a little while using a normal torque method, it has a large effect. But with stretchy bolts, a large difference is a small effect by comparsison. In fact, once you start to stretch the bolt the torque will level off and then lower until it fails from fatigue.
I'm no mechanical engineer, but this is how I understand it.
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Something else to add that I didnt see in that thread. The way you torque the bolts is very important as well. Be sure to follow the patter in the manual. Its basically just a pattern moving outwards from the center 2 studs. Dont go straight to the 85 or whatever ftlbs you are going to torque it to. Do it in a few stages.
You want the last stage to be the biggest jump in torque. For example, lets say the last stage brought to 75 pounds. Chances are that when you set your torque wrench to 85 pounds, you wont even be able to move the nut, it will just click. Its like you ebrake. There isnt enough friction to slow the car down very well when it is moving, but when the car is stopped it holds it very well.
It takes a good bit of force to get that nut moving again against all the driction in the washer/threads. I suggest 20, 40, 85. Do it smooth and dont stop moving the wrench until it clicks!
Make you have enough range motion to swing it far enough around. Dont stop. If you do, back it off a little and do it again.
So the moral of the story is to chase the threads with the right tap
(m12x1.25 for 6 bolt block, m11x1.25 for 7 bolt), clean and dry the hole after tapping, use only ARP brand moly lube (most stud kits come with a small pouch, but not all of them!), and use proper torque wrench techniques.
Obviously be sure the block and head are clean and within flatness specs. |
Link--> ARP Head Stud installation
For "Gen 2" 4G63's use newer OEM Evo 8, 5-ply, cylinder head gasket to improve sealing.
Then use new oil-pan gasket (and rocker cover etc.) to prevent oil-leaks.
More to come later... 4G63 TUNING: Compatible Upgrade Alternatives - # 2.
 Additional Tips and suggestions welcomed.
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Walk softly... and carry a BIG stick!  |
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