Jabronie Posted September 12, 2021 Share #1 Posted September 12, 2021 I've heard coldIntake .20mmExhaust .25mm And .17mm intake.24mm exhaust Car is stock 77 l28 Sent from my Pixel 2 XL using Tapatalk Link to comment https://www.classiczcars.com/topic/65816-what-valve-specs-yall-like-for-adjusting/ Share on other sites More sharing options...
AK260 Posted September 12, 2021 Share #2 Posted September 12, 2021 Let me be the first to be controversial and I know this isn’t the question you asked:I fundamentally disagree with doing them hot! Reason? Can you keep the engine temp constant at “hot” over the 30-60 mins it takes to do the job? But cold is not going to fluctuate. My personal experience has been that by the time I finish and go back to cyl 1 to double check, the clearances have changed! ;) So for a rookie like me, I like doing them cold.Secondly, this web page I LOVE:https://www.engine-specs.net/nissan/l28.htmlI do mine a fraction tighter than spec but let me not elaborate with an essay as to why. 4 Link to comment https://www.classiczcars.com/topic/65816-what-valve-specs-yall-like-for-adjusting/#findComment-628441 Share on other sites More sharing options...
Jabronie Posted September 13, 2021 Author Share #3 Posted September 13, 2021 Let me be the first to be controversial and I know this isn’t the question you asked:I fundamentally disagree with doing them hot! Reason? Can you keep the engine temp constant at “hot” over the 30-60 mins it takes to do the job? But cold is not going to fluctuate. My personal experience has been that by the time I finish and go back to cyl 1 to double check, the clearances have changed! ;) So for a rookie like me, I like doing them cold.Secondly, this web page I LOVE:https://www.engine-specs.net/nissan/l28.htmlI do mine a fraction tighter than spec but let me not elaborate with an essay as to why. Thanks for the link. I just bookmarked it.Your thoughts on adjusting hot makes sense. So would you recommend cold at Intake 008inches Exhaust 010 inches Sent from my Pixel 2 XL using Tapatalk Link to comment https://www.classiczcars.com/topic/65816-what-valve-specs-yall-like-for-adjusting/#findComment-628445 Share on other sites More sharing options...
AK260 Posted September 13, 2021 Share #4 Posted September 13, 2021 Thanks for the link. I just bookmarked it.Your thoughts on adjusting hot makes sense. So would you recommend cold at Intake 008inches Exhaust 010 inches Sent from my Pixel 2 XL using TapatalkMost welcome.What you quoted is the correct recommended factory standard (cold) and it’s good to go with that.I set mine cold at:Intake: 0.15 mm (0.006”)Exhaust: 0.2 mm (0.008”)It’s good practice to also check head bolts torque at the same time: the FSM quotes 51-61lbft or 7.0-8.5kgm. I recommend setting your torque wrench to the lower number to avoid over-tightening. Link to comment https://www.classiczcars.com/topic/65816-what-valve-specs-yall-like-for-adjusting/#findComment-628466 Share on other sites More sharing options...
Racer X Posted September 13, 2021 Share #5 Posted September 13, 2021 (edited) 16 hours ago, AK260 said: Let me be the first to be controversial and I know this isn’t the question you asked: I fundamentally disagree with doing them hot! Reason? Can you keep the engine temp constant at “hot” over the 30-60 mins it takes to do the job? But cold is not going to fluctuate. My personal experience has been that by the time I finish and go back to cyl 1 to double check, the clearances have changed! 😉 So for a rookie like me, I like doing them cold. Secondly, this web page I LOVE: https://www.engine-specs.net/nissan/l28.html I do mine a fraction tighter than spec but let me not elaborate with an essay as to why. I've said it before, I can get the valves checked and adjusted in 15 to 20 minutes. So I always do them hot. Sure, when putting a fresh engine together, they need to be set cold, and the clearances need to be set accordingly. I also set them a bit tighter than the manual calls for. For racing it is a way to "cheat" a bit more lift and duration out of the cam profile. Edited September 13, 2021 by Racer X 1 Link to comment https://www.classiczcars.com/topic/65816-what-valve-specs-yall-like-for-adjusting/#findComment-628470 Share on other sites More sharing options...
jonbill Posted September 13, 2021 Share #6 Posted September 13, 2021 I always set my clearances cold when I'm going to run the engine cold. 1 Link to comment https://www.classiczcars.com/topic/65816-what-valve-specs-yall-like-for-adjusting/#findComment-628481 Share on other sites More sharing options...
Mark Maras Posted September 13, 2021 Share #7 Posted September 13, 2021 I've set them cold and hot. Both methods worked for me. 2 Link to comment https://www.classiczcars.com/topic/65816-what-valve-specs-yall-like-for-adjusting/#findComment-628482 Share on other sites More sharing options...
Jeff G 78 Posted September 13, 2021 Share #8 Posted September 13, 2021 Set them cold and check them hot to verify. If anything is a tad off, I can adjust one or two while it's still hot. 4 Link to comment https://www.classiczcars.com/topic/65816-what-valve-specs-yall-like-for-adjusting/#findComment-628489 Share on other sites More sharing options...
Captain Obvious Posted September 14, 2021 Share #9 Posted September 14, 2021 jonbill's method is the same one I use. Works for me. Link to comment https://www.classiczcars.com/topic/65816-what-valve-specs-yall-like-for-adjusting/#findComment-628500 Share on other sites More sharing options...
Jabronie Posted September 14, 2021 Author Share #10 Posted September 14, 2021 I've said it before, I can get the valves checked and adjusted in 15 to 20 minutes. So I always do them hot. Sure, when putting a fresh engine together, they need to be set cold, and the clearances need to be set accordingly. I also set them a bit tighter than the manual calls for. For racing it is a way to "cheat" a bit more lift and duration out of the cam profile. If you know what you're doing, it's 15-20min to adjust valves? Ok i wasn't sure if being a little tighter would be badSent from my Pixel 2 XL using Tapatalk 1 Link to comment https://www.classiczcars.com/topic/65816-what-valve-specs-yall-like-for-adjusting/#findComment-628521 Share on other sites More sharing options...
Racer X Posted September 14, 2021 Share #11 Posted September 14, 2021 1 hour ago, Jabronie said: If you know what you're doing, it's 15-20min to adjust valves? Ok i wasn't sure if being a little tighter would be bad Sent from my Pixel 2 XL using Tapatalk Knowing the job, having the correct tools, and planning are the keys to a quick, hot valve check and adjustment. As for running them a bit tighter to get that little extra bit of lift and duration, one mustn’t get them too tight, or the valves won’t close fully with the engine at full operating temperature. 2 Link to comment https://www.classiczcars.com/topic/65816-what-valve-specs-yall-like-for-adjusting/#findComment-628525 Share on other sites More sharing options...
Zed Head Posted September 14, 2021 Share #12 Posted September 14, 2021 RacerX, this is how these valve lash adjustment threads always end up. The guys that have done many and have practiced (that's the real key to speed - practice), and have calloused burnt finger tips, say it's easy and everyone should do them hot. "It's easy, don't be a weeny!". They have forgotten that their first time probably took a couple of hours. Logically, setting cold and checking hot has no flaws, except time spent. In the big scheme of things, for a guy with an engine that's new to him, the time spent looking at the engine parts with no reason to hurry might be more valuable than actually adjusting the lash. Plus, mistakes in lash settings can cost a lot of money. One hanging valve and the head might have to come off. 2 2 Link to comment https://www.classiczcars.com/topic/65816-what-valve-specs-yall-like-for-adjusting/#findComment-628533 Share on other sites More sharing options...
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