Lashing valves--EOIC vs. the MP Chart

beanhead · Nov 14, 2020

Just for general info----
I've always used the 'EOIC' method and a starter switch, but since I was just futzing around in the garage yesterday evening I thought I'd try running the valves both ways.
"What the fudge I've never used the TDC chart, but people say they like it....maybe it's nice not turning the engine as much."
So I set them according to the chart. Then as I went through them again checking at EO-IC, I found them all to be loose by .002"-.003". Doh! I'd read that the chart method may not always be dead on, for every cam/combo, and I experienced it with my little back-to-back test.
I go .006" tighter than hot spec for aluminum head growth and it gets me right on. So if I called it good with the chart I'd be a few thou loose at battle temperature. FWIW my cam would be in the 'medium-performance' category I suppose, in a 505". It's a SFT with 282adv/251 @ .050"/.555" intake lift/112 LSA. Hot lash per spec is .020". Not the full-speed agressive lobes but not an easy-rider either.
So....choose your method carefully!

(This is the chart I'm talking about)

threewood · Nov 14, 2020

I use the chart. Definitely more helpful if the damper is marked every 90 degrees.

beanhead · Nov 14, 2020

threewood said:
I use the chart. Definitely more helpful if the damper is marked every 90 degrees.

Yeah for sure...Mine is marked all the way around and the TDC mark was verified during assembly.
What I discovered was, you might not be 'exactly' where you think you are with the chart.

65Fury440 · Nov 15, 2020

Very timely posting.
I just did the same thing, but mine were all loose on the exhaust side only, .003-4

dvw · Nov 15, 2020

You ever try to turn a 15-1 motor with 310/810 spring pressure? Good luck. EOIC with a button mounted in the engine compartment. Wired so it sends a hot 12v to the tab with the yellow wire on the stater relay. 30 minutes if your slow.
Doug

beanhead · Nov 15, 2020

dvw said:
You ever try to turn a 15-1 motor with 310/810 spring pressure? Good luck. EOIC with a button mounted in the engine compartment. Wired so it sends a hot 12v to the tab with the yellow wire on the stater relay. 30 minutes if your slow.
Doug

Trying to hand-turn an engine like that in the car just sounds like punishment.
I use a remote starter switch; all 16 valves 15-20 minutes tops. Sometimes I think I waste more time dropping valve cover bolts into the K-frame than actually running the valves

Green72 · Nov 19, 2020

I'm about to set lash on my new motor. It's my first time. I am familiar with the TDC chart. Could someone explain the EOIC method?

beanhead · Nov 19, 2020

Green72 said:
I'm about to set lash on my new motor. It's my first time. I am familiar with the TDC chart. Could someone explain the EOIC method?

You need a remote starter switch/button/something...or you could use a screwdriver/butterknife/whatever directly on the starter relay but it might be hard to see the passenger side rockers.
Pull the coil wire.
Start with cylinder#1. (Any cylinder is fine that's just where I start).
While watching the exhaust valve, bump the starter until the Exhaust valve starts to Open. Set the lash on that cylinder's Intake valve.
Now bump the starter until that same cylinder's Intake valve opens, watch it and keep bumping until it starts to Close and lash that cylinder's Exhaust valve. Repeat for the other 8.
Best to do it when the engine's dead cold (been shut down at least overnight.)
Then check the lash immediately after getting the engine good and hot and see if it's at the hot lash spec for your cam. If not, do another cold lash and add/subtract the difference.

ckessel · Nov 20, 2020

I always used the chart and a long handled 1/2" drive ratchet.

68 HEMI GTS · Nov 20, 2020

That chart is a waste of time, there’s only a handful of cams that it actually puts on the base circle.

forphorty · Nov 20, 2020

Green72 said:
I'm about to set lash on my new motor. It's my first time. I am familiar with the TDC chart. Could someone explain the EOIC method?

EOIC means to adjust the intake valve as you see the Exhaust just begin to Open, and adjust the exhaust right after the Intake Closes.

Green72 · Nov 21, 2020

Got it
Thanks everyone

Lashing valves--EOIC vs. the MP Chart

beanhead

May I Land My Kinky Machine

threewood

FBBO Gold Member

beanhead

May I Land My Kinky Machine

65Fury440

Well-Known Member

dvw

FBBO Gold Member

beanhead

May I Land My Kinky Machine

Green72

FBBO Gold Member

beanhead

May I Land My Kinky Machine

ckessel

Well-Known Member

68 HEMI GTS

Well-Known Member

forphorty

Well-Known Member

Green72

FBBO Gold Member

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