johnegg Posted January 14, 2011 Share Posted January 14, 2011 i have edited my post, thanks. that was on the next page when i was doing the copy and paste thing. Link to comment Share on other sites More sharing options...
camroncamera Posted January 14, 2011 Share Posted January 14, 2011 I agree that nowhere in those pages does it specify to use new head bolts, yet it does specify to use new head gaskets. Link to comment Share on other sites More sharing options...
I Donated broknindarkagain Posted January 14, 2011 I Donated Share Posted January 14, 2011 lol...... Just use new head bolts -broknindarkagain My Current Project - Click Here COME AND TAKE IT "The only thing necessary for the triumph of evil is for good men to do nothing." Link to comment Share on other sites More sharing options...
KuNomn Posted January 15, 2011 Share Posted January 15, 2011 Let me throw this knife into the the scuffle. . . Replacing head bolts with head studs? Link to comment Share on other sites More sharing options...
amorgan93 Posted January 27, 2011 Author Share Posted January 27, 2011 soo no-one answered about using a Gates belt... any opinions? Link to comment Share on other sites More sharing options...
subikid90 Posted January 27, 2011 Share Posted January 27, 2011 Gates timing belt? I have used them on both of my subis with no problems. Havent heard of anyone not liking them -Subikid90 1997 Legacy GT 5spd & EJ251 w/EJ25D heads ~10.5CR 1998 Legacy GT Limited waiting for EJ22T hybrid swap Link to comment Share on other sites More sharing options...
amorgan93 Posted January 27, 2011 Author Share Posted January 27, 2011 Gates timing belt? I have used them on both of my subis with no problems. Havent heard of anyone not liking them sweet. Gates it shall be. saves me money too Link to comment Share on other sites More sharing options...
BAC5.2 Posted January 27, 2011 Share Posted January 27, 2011 1) Gates makes great belts. No problem using them. 2) Johnegg - The tighten sequence is called "Angle Controlled Tightening" which is designed to reliably torque bolts. Not all torque wrenches read the same, nor do they properly allow axial de-straining required to achieve consistent preload. The majority of ACT procedures are designed to bring the bolts very close to yield. In most cases, ACT processes provide less than 5% variation to yield. A slight over-torque makes the bolt no longer usable. Best practice? Replace the head bolts each time. Head studs do NOT need to be replaced each time, and are a pretty good idea. I believe ARP has it's own installation torque procedure. It's pretty important that you follow the right directions. [URL="http://legacygt.com/forums/showthread.php/proper-flip-key-interesti-159894.html"]Flip Key Development Thread[/URL] "Genius may have its limitations, but stupidity is not thus handicapped." - E. Hubbard Link to comment Share on other sites More sharing options...
johnegg Posted January 28, 2011 Share Posted January 28, 2011 1) Gates makes great belts. No problem using them. 2) Johnegg - The tighten sequence is called "Angle Controlled Tightening" which is designed to reliably torque bolts. Not all torque wrenches read the same, nor do they properly allow axial de-straining required to achieve consistent preload. The majority of ACT procedures are designed to bring the bolts very close to yield. In most cases, ACT processes provide less than 5% variation to yield. A slight over-torque makes the bolt no longer usable. Best practice? Replace the head bolts each time. Head studs do NOT need to be replaced each time, and are a pretty good idea. I believe ARP has it's own installation torque procedure. It's pretty important that you follow the right directions. well this is the first any one here has recommended replacing the bolts for any reason other than ''the manual says so''. i can not argue with your statements because i have no knowledge of ''ARP'', it is new to me. i'll have to read up on it. but i can still state with confidence that the FSM does not recommend replacing the head bolts. and the folks over at www.ultimatesubaru.org do not recommend replacing them either. and i have complete confidence in both. so i still disagree. but each to his own. Link to comment Share on other sites More sharing options...
amorgan93 Posted January 30, 2011 Author Share Posted January 30, 2011 well this is the first any one here has recommended replacing the bolts for any reason other than ''the manual says so''. i can not argue with your statements because i have no knowledge of ''ARP'', it is new to me. i'll have to read up on it. but i can still state with confidence that the FSM does not recommend replacing the head bolts. and the folks over at www.ultimatesubaru.org do not recommend replacing them either. and i have complete confidence in both. so i still disagree. but each to his own. i can see what your saying my dad (a mechanic for 30 some years) was really confused at how little these head bolts torqued. I may or may not replace them. Link to comment Share on other sites More sharing options...
amorgan93 Posted January 30, 2011 Author Share Posted January 30, 2011 oil pump o-ring - 1 ea. do you mean the little o ring inside the pump? Link to comment Share on other sites More sharing options...
BAC5.2 Posted January 30, 2011 Share Posted January 30, 2011 well this is the first any one here has recommended replacing the bolts for any reason other than ''the manual says so''. i can not argue with your statements because i have no knowledge of ''ARP'', it is new to me. i'll have to read up on it. but i can still state with confidence that the FSM does not recommend replacing the head bolts. and the folks over at www.ultimatesubaru.org do not recommend replacing them either. and i have complete confidence in both. so i still disagree. but each to his own. As I said. You can disagree, but you are still wrong. But first, ask if the people suggesting you don't replace them are only saying so because the FSM doesn't explicitly state to do so. I'll do you a few better for proof. Honda has a very similar tightening process to our cars when replacing head gaskets. In their FSM, it explicitly states to replace the headbolts. Chilton explicitly states to reuse headbolts at MOST one time. If you didn't buy the motor new, it's safe to assume that the previous owner took it apart unless you have documentation to suggest otherwise. Ford, in the FSM for the Taurus, requires the replacement of headbolts when the heads are removed from the engine. IIRC the FSM says something like "Remove cylinder heads. Discard cylinder head retaining bolts". Ford actually includes headbolts in the headgasket kit for the Vulcan motor. It's $80. Eat Ramen for a week, and you can afford to spend $80 so that you only have to do the job once. Is it worth the risk? Just because the FSM doesn't explicitly state to do it, doesn't mean it isn't good practice. [URL="http://legacygt.com/forums/showthread.php/proper-flip-key-interesti-159894.html"]Flip Key Development Thread[/URL] "Genius may have its limitations, but stupidity is not thus handicapped." - E. Hubbard Link to comment Share on other sites More sharing options...
Baddog Posted January 30, 2011 Share Posted January 30, 2011 When I plan to have my heads rebuilt I am going to go with new head bolts as well. It's one of those things to me. If you're in there. You might as well do it. Link to comment Share on other sites More sharing options...
jamal Posted January 31, 2011 Share Posted January 31, 2011 I've re-used mine twice now. and done so on countless other builds. would love to see an example of re-used bolts causing a problem. Link to comment Share on other sites More sharing options...
amorgan93 Posted January 31, 2011 Author Share Posted January 31, 2011 looking into buying a 96 impreza now with transmission problems. askin 300 for the whole car with a strong motor. Depending on how many miles it has on it, ill most likely buy it. It will be a loss of 20 hp but oh well Link to comment Share on other sites More sharing options...
johnegg Posted March 24, 2011 Share Posted March 24, 2011 not that any one is interested, but i found this info on head bolts. The head bolts end up right around 90ftlbs when you follow the tightening instructions. I did the degree turns using my digital torque wrench, and they all tighten about the same on the final quarter turn. First off - all bolts stretch to some degree. There is a BIG difference between stress and yield.... in metalurgical terms the stress at which the material starts to exhibit permanent deformation is called yield. Subaru head bolts do stretch but they DO NOT exprience permanent deformation - thus can be reused an indefinite number of times. The reason for the degree turns is purely one of practicality - because the Subaru head bolts tend to creak in a large percentage of cases even when the threads are properly chased and the bolts are clean and lubed - the degree turns are set to put about 90 ft/lbs on the bolts. The creaking will throw off a regular torque insturment. Degree turns are impervious to creaking. So no - Subaru head bolts are NOT torque-to-yield. GD Link to comment Share on other sites More sharing options...
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