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Discussion Starter #1
My solid roller cam is supposed to have lash set at .020 on the intake and .020 on the exhaust when it's hot. Where's it supposed to be set at when cold? (First time being run if it matters.) Thanks!
 

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Just another Wannabe
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Every engine grows different. If it has a standard deck iron block and fairly stock iron heads, the growth is usually minimal. .002 or so. Aluminum heads grow more. (around .002- .003 more than with iron heads.) Tall deck blocks grow more and WOW when you get to tall deck aluminum blocks with aluminum heads.
Just guess what they may be, but keep a good record. Then measure it when it has been hot for a while and that is the only foolproof way to test each individual engines growth.
 

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Discussion Starter #4
Iron block with aluminum heads. So it sounds like they expand when they get hot (I should have known that). Maybe set them at .023 cold and then after running it for a while check it when it's hot?
 

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Boat Nut
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Iron block with aluminum heads. So it sounds like they expand when they get hot (I should have known that). Maybe set them at .023 cold and then after running it for a while check it when it's hot?
The engine is growing height wise, so you would subtract from the .020
 

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mo balls than $cents$
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Iron block with aluminum heads. So it sounds like they expand when they get hot (I should have known that). Maybe set them at .023 cold and then after running it for a while check it when it's hot?
my cam calls for 20 also, i set em 22 cold, and i've checked them hot. the 20 was tight but fine. also runnin iron block,alum heads.
 

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Just another Wannabe
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Every iron block and aluminum headded deal I have ever ran wants to be about 4 to 5 thou tighter when it is cold. I would try about .016 to .017 cold. Then check it when it is hot. Every engine is a little different. And every engine also wants to run at different temperatures and as such, different amounts of growth.
 

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Resident Ford Nut
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Iron block with aluminum heads. So it sounds like they expand when they get hot (I should have known that). Maybe set them at .023 cold and then after running it for a while check it when it's hot?
The clearance should "grow" .002-.004 from cold to hot. Set at .018 cold should be about .020-.021 hot.

The Alumi heads on the 565" grow and change the valve lash from .024 cold the .026 hot.

You guy's got me scratching my head there for a minute. :)bulb

Sleeper CP :D
 

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stock cast block with aluminum heads.i se them 4thousandths tighter cold.say .020 i se them .016

iron heads i set them 2 thousandths tighter;)i have checked several motors when hot and they always seem to be right on or close to it.good luck.:Dtravis
 

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Discussion Starter #10
The guy that's putting the engine together for me said he wasn't sure if he could make it out until Sunday evening to finish my engine. I don't have anything to do until he's done. I don't have side work, 8 -5 work, nothing. So I started thinking I should just finish it myself. So I started this thread. He'll be out here in less than an hour to finish my engine. Thanks for the replies!!!

Makes me wonder if anyone saw this thread... :)hand
 

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So I started thinking I should just finish it myself. So I started this thread. He'll be out here in less than an hour to finish my engine. Thanks for the replies!!!

Makes me wonder if anyone saw this thread... :)hand
So, will you be using the EOIC ( or what ever it is) method or TDC ?

Sleeper CP :)bulb
 

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Set the intake at .022 and the exhaust at .024.Recheck after a real good warm-up. Please remember that aluminum heads require more heat to work and conform to a iron block. 195 running temp is okay. I may be wrong here but when was the last time you saw a REAL race care with a radiator??? For that matter what does the temp gauge say on a daily driver with aluminum heads say... I know the gauge doesn't say any thing you have to read it!!!!!!!!!!!! IMO. M
 

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CarbGuy
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I may be wrong here but when was the last time you saw a REAL race care with a radiator???

Every Cup car out there, Every Pro-Stock car out there ALL have Radiators. There are a couple of Drag Race classes that run solid (no water) blocks but the overwhelming majority run water, and radiators.

As far as the temp they run it depends on what you're trying to do, but the colder they run the better they perform in a RACE only application. Pro-Stock cars will be about 100° to 110° at the end of a run.
 

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Just another Wannabe
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Like Warren Johnson says- he would freeze the engine if he could, as long as the oil was hot.
Like rum said, more real race cars with radiators than ones without. But not sure what this has relevance to, this is a boat with a lake full of radiated water. Get the boat to operating temp and call that the "Hot" side of where the lash will run.
 

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I'm sorry but I have been around to much race shit to see anybody run a car cold. The last time I was in the NASCAR pits the average motor temp was 210-220. The car I help on tune runes @ 180-210. But hell what do I know It's only an 8 second car. Didn't mean to ruffle feathers. M
 

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I've tested this on my tall deck aluminum head / iron block BBC. I run 140 degree water temps and the lash opens up .004" to .005" when hot. My target valve lash is .025" so I set them cold at .020". Works like a charm!;) Iron heads and iron block will close the cold lash .002-.003. Being +/- .002" on the lash will not alter perf so get a consistent system / feel for setting the lash and get it within .002" and you will be good to go.
 
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