New threads and interesting conversations directly in your inbox. Sign up now and get a daily summary of the latest forum activities!
Discussion in 'A Work In Progress' started by stevehuckss396, Jun 7, 2010.
I sent you an email with all the pictures Enjoy
The following has been copied from "search for vee 8 plans"
There have been no replies. Surely some one can help?
Well I have made the camshaft to Steves chart and it "looks" fit for purpose, but I still can,t work out how the cross marks in the chart are worked out and I like to understand what I am doing.
Once again can anyone give me a pointer?
I have swapped some emails with this fellow and I think everything is good to go.
Can you email me again and give us some clues as to where I am going wrong!
I am allowing for direction of rotation, gearing, the Vee of the cylinders.
Is there something else?
Just finishing the cam and distributor gears.(from scratch)
what exactly is going wrong? Is it the proceedure that is confusing? Tell me what specifically is the trouble and i will do all i can to help.
I am trying to prove that the cam chart is right , using the 3 things I have mentioned. (and the firing order which I missed out)!!
Is there a spread sheet with formula?
As I said before I like to understand how things are arrived at.
Follow only the exhaust lobes on the chart in the order of fire. EX1 starts at zero degrees. Ex8 is next to fire and should lag #1 by 45 degrees. Using a clockwise degree wheel 45 degrees behind 0 is 315 degrees. Cylinder #8 is on the opposite bank so it has to lag by an additional 90 degrees so the #8 lobe needs to lag #1 by 135 degrees. That puts #8 lobe at 225 degrees.
The even cylinders need 90 degrees additional lag to allow for the 90 degree Vee angle
#1 - 0 zero degrees
#8 - 45 + 90 360 - 45 - 90 = 225 degrees
#4 - 90 + 90 360 - 90 - 90 = 180 degrees
#3 - 135 360 - 135 = 225 degrees
#6 - 180 +90 360 - 180 - 90 = 90 degrees
#5 - 225 360 - 225 - 135 degrees
#7 - 270 360 - 270 - 90 degrees
#2 - 315 + 90 360 - 315 - 90 = -45 degrees With a negative number go 360 - 45 = 315
Once you figure out where all the exhaust lobes should be, the intake lobes lag there exhaust lobes by 110 degrees
That was helpful to me also. Thanks Steve! Maxi
I am most grateful for your explanation, I can now see how to do it properly.
Hi Steve, I thank you also as this will be of great assistance to me in the future.
Anyone know what the valve clearance is?
I am not ready for it yet just getting facts together.
I would say as long as it has some clearance then it will be fine. It's not like it's going to run for extended periods where everything gets thoroughly hot, expands and clearances reduce. If you make it to large you're reducing your cam lift and duration, which won't affect it all that much anyway - again it's not like full size where we're chasing maximum power. So I'd just set them so it has a little clearance by feel and call that good enough.
Do the valve cages sit flush with the head cylinder cut out? or are they .017 below.
Depth of recess in head .397 length of cage .38
They do not look right when .017 below and would presumably restrict gas flow as valve head would only just fit in, waiting loctiting so answer would be appreciated.
They should be .017 below. When the valve is installed it will be flush with the surface or real close to flush. There is plenty of lift and duration in the cam to get the cylinder filled up.
Thanks for your reply, you are most helpful.
What is the clutch bearing for in the balancer at the front of the engine on the crankshaft?
Thanking you in advance
The clutch bearing is for starting the engine. The bearing spins like a standard roller bearing in one direction and locks up in the other. A 1/4 inch shaft can be inserted into the bearing and rotated clockwise. The bearing locks clockwise so the engine spins over in the clockwise direction. When the engine starts the crankshaft speed will exceed the starter speed so the bearing will release and spin on the starter shaft until you pull it out.
Once again thanks for your swift response.
On page 108 Steve says "superglue electrode on to rotor ".
Any particular type of super glue for Delrin to brass or just standard super glue?
P.S. The parts too be made list is getting shorter!!!
Separate names with a comma.