[HWYSTR455]

Originally Posted by STEELCITYFIREBIRD

You got three options... as I see it;
1-Listen to the noise (not me)
2-Get oil everywhere, adjust running (only when all else fails)
3-Run valves once again,
* use/have no tools on polylock while finding zero lash, eliminates any
possible interference
* use correct method (links below) to place lifter on base circle of cam
* determine how much travel/turn on polylock from opening valve to zero lash
and split that for your set point from zero lash, or bottomed (bottomed up is easier and more precise) a third method is with a feeler gauge/plunger bottomed but I won't go there


https://www.hotrod.com/articles/comp...aulic-lifters/

https://www.jesel.com/instructions (btw/I cut and paste a partial post from here to save me time while @ work!)

Time to !

That's funny Hot Rod says they got that info from Comp, because if you look at my original post, as well as the snip in my last post, you will see that is from Comps' printed adjustment procedures.

.

[STEELCITYFIREBIRD]

Originally Posted by HWYSTR455

That's funny Hot Rod says they got that info from Comp, because if you look at my original post, as well as the snip in my last post, you will see that is from Comps' printed adjustment procedures.

.

http://www.cpgnation.com/forum/threa...justment.1937/

"Next, we’ll adjust the exhaust valves. To do so, you need to turn the engine over until the intake pushrod moves all the way up. Rotate just past maximum lift, where the intake will begin to close. The lifter is now at the base circle, and the exhaust valve can be adjusted. Note: DO NOT go too far down (over halfway) past the point of maximum lift. If you go too far, you will be in the overlap cycle – where intake valve lash is being taken up as the exhaust valve begins to open"

Anyhow, that's how I do them, solid or hydraulic lifters.


.

[TAQuest]

In the 'adjusting the lifter' part of this, finding the base circle didn't seem that difficult.

The one post that helped me the most was this hint from Clay to check my technique used to tighten the polylocks.

I missed that last 'turning the nut down' after tighening the set screw.

If I hadn't learned the correct way I would have been chasing these locks around for a while.

Originally Posted by "QUICK-SILVER"

If you adjusted valves like you was doing the distributor install....You need to go back and adjust valves again.

How much preload did the new lifters call for?

How did you check the preload?

What technique did you use to lock the polylocks down? Need to turn the nut for the final lock instead of just tightening the set screw.

Clay

[pastry_chef]

Originally Posted by STEELCITYFIREBIRD

Note: DO NOT go too far down (over halfway) past the point of maximum lift. If you go too far, you will be in the overlap cycle – where intake valve lash is being taken up as the exhaust valve begins to open"

If the intake lobe is closing you are not even close to the exhaust lobe ramp.

Sounds like you are skipping over most of the compression stroke and power stroke in your mind.

I can provide EXACT ramp numbers on any Comp lobe if desired.

[HWYSTR455]

Originally Posted by STEELCITYFIREBIRD

http://www.cpgnation.com/forum/threa...justment.1937/

"Next, we’ll adjust the exhaust valves. To do so, you need to turn the engine over until the intake pushrod moves all the way up. Rotate just past maximum lift, where the intake will begin to close. The lifter is now at the base circle, and the exhaust valve can be adjusted. Note: DO NOT go too far down (over halfway) past the point of maximum lift. If you go too far, you will be in the overlap cycle – where intake valve lash is being taken up as the exhaust valve begins to open"

Anyhow, that's how I do them, solid or hydraulic lifters.


.

Probably is fine, as long as it's after the full open, but pretty sure the overlap is somewhere at the beginning of the intake valve opening. Immediately after the closing of the intake valve is a compression stroke. My understanding is that the overlap is at the beginning of the intake valve opening. Like I said, I grabbed that info from comps' site, with the URL to the doc, but no sense beating this horse.

On the poly locks, you make the adjustment after you've reached zero preload as usual, such as a 1/2 turn, then back off like a 1/16-1/8 of a turn snug the set screw down, then crank back to the original position of the adjustment, hold the allen wrench and move both the wrench and allen wrench at the same time.

Some cam profiles slope the closing of a valve off slowly at the end, and can hold the valve open briefly at say .100-.200 lift, and that can be easily mistaken for the base circle of the lobe. That's why you use valve events to determine the base circle.

.

[TAQuest]

Originally Posted by HWYSTR455

Probably is fine, as long as it's after the full open, but pretty sure the overlap is somewhere at the beginning of the intake valve opening. Immediately after the closing of the intake valve is a compression stroke. My understanding is that the overlap is at the beginning of the intake valve opening. Like I said, I grabbed that info from comps' site, with the URL to the doc, but no sense beating this horse.

On the poly locks, you make the adjustment after you've reached zero preload as usual, such as a 1/2 turn, then back off like a 1/16-1/8 of a turn snug the set screw down, then crank back to the original position of the adjustment, hold the allen wrench and move both the wrench and allen wrench at the same time.

Some cam profiles slope the closing of a valve off slowly at the end, and can hold the valve open briefly at say .100-.200 lift, and that can be easily mistaken for the base circle of the lobe. That's why you use valve events to determine the base circle.

.

Not sure about you but I find it hard to miss the base circle. Not that tricky. Wouldn't want someone to think it's harder than it is. That could make the job harder rather than easier. The instructions that came with the cam made it easy. I posted them word for word and they work.

[TAQuest]

Here are the instructions that came with the Voodoo 703 cam that I installed with the Edelbrock round port heads.

Originally Posted by TAQuest

It says(word for word) to rotate the engine in the normal direction of rotation until the exhaust valve begins to open. At this point adjust the intake valve to zero lash with no pre load at the lifter, then tighten one more half turn. Rotate the engine again until the intake valve has fully opened. Now you can adjust the exhaust valve to zero lash, then 1/2 more turn. Repeat this procedure until each cylinder is completed.

[TAQuest]

When I called the Lunati tech he said I might need different push rods but didn't offer any advice on how to decide on what length I needed. It turned out that the originals worked fine with the 1.5 rockers.
I found that the post below with the link to the turtorial on checking the travel of the rocker roller on the valve stem was very helpful to know if your pushrods were the right length for your combination of variables.

Originally Posted by STEELCITYFIREBIRD

http://lunatipower.com/Tech/Valvetra...nGeometry.aspx

Trying to see rocker to spring/retainer , valve closed like this:

You may need different pushrods

[TAQuest]

Finally had time to test drive. It runs like a beast on the back roads but not so drivable in the city. Lots of surging trying to go 30 mph.

Can it be tuned for city driving or too big a cam for that?

[pastry_chef]

Originally Posted by TAQuest

Can it be tuned for city driving

100%

Consider something like this.
https://www.summitracing.com/int/par...0300/overview/

[Squidward]

Originally Posted by TAQuest

Finally had time to test drive. It runs like a beast on the back roads but not so drivable in the city. Lots of surging trying to go 30 mph.

Can it be tuned for city driving or too big a cam for that?

That cam should be able to make 15" at idle with a decent tune. Are you running a vacuum advance? Maybe you need an adjustable unit that can accommodate your new lower vacuum levels?

[TAQuest]

Not a great cam for the street. Thought the front tires were going to come off the ground hitting 3rd gear. Lots of fun on the open road but not going to work for city driving. You can do it but it's a PITA. Going to need another cam right away.

The 'ticking' noise is definitely lifters. It moves around from one to another. Not sure what's going on there. Maybe the next set of lifters will be better.

[TCSGTO]

I would spend some more time tuning before tearing out the cam. It’s going to be a bit choppy in a 400 and probably need some richening of the carbs’ idle feed circuit to get it drive good down low but it’s really not that radical.
Double,triple, and quadruple check firing order, especially #5 &#7. It’s easy to swap those 2 and the car will run but pop out of the carb at low speeds. Not that I’ve ever done that.

[pastry_chef]

Originally Posted by TAQuest

not going to work for city driving.

Zero effort tuning and a dead wrong statement!
Self inflicted pain.

Originally Posted by TCSGTO

I would spend some more time tuning before tearing out the cam.

So many quitters in the world, apparent everyday to me. It's too hard.. LMAO

[STEELCITYFIREBIRD]

....Advance the cam timing “some”!
😆

["QUICK-SILVER"]

Originally Posted by TAQuest

The 'ticking' noise is definitely lifters. It moves around from one to another. Not sure what's going on there. Maybe the next set of lifters will be better.

Are you still doing the 1/2 turn on the preload?

Not enough is not enough. Most any brand lifter is going to have some tick that moves around if it doesn't have enough preload.

When you hear lifter tick, especially moving around or coming and going, this tells you valve open or close is changing around. No one cylinder will fire with the same umph every time if valve events are changing. On a scale of one to ten...Tuning requirements would be eleven plus. Or possibly require some state of de-tune to make cylinders hit weaker?

Best I can tell, the 703 cam only has 53° of overlap. That's mildish stock cam range. Should be able to get it running "fairly" smooth at low rpm's. Now if you're wanting to lug along in high gear at idle speed...should've got the original cam running right because that's what it was designed for.

Get valves adjusted "RIGHT" and forget generic fit-um-all directions.

Get a timing light so you can fine tune the engine. It's not just for setting initial timing. You can use it to watch the advance curve and see what's really going on. Can't do that by ear.

Get a good vacuum gauge and learn how to use it. That's old school tuning that does still work today.

Clay

[TAQuest]

Originally Posted by "QUICK-SILVER"

Are you still doing the 1/2 turn on the preload?

Not enough is not enough. Most any brand lifter is going to have some tick that moves around if it doesn't have enough preload.

When you hear lifter tick, especially moving around or coming and going, this tells you valve open or close is changing around. No one cylinder will fire with the same umph every time if valve events are changing. On a scale of one to ten...Tuning requirements would be eleven plus. Or possibly require some state of de-tune to make cylinders hit weaker?

Best I can tell, the 703 cam only has 53° of overlap. That's mildish stock cam range. Should be able to get it running "fairly" smooth at low rpm's. Now if you're wanting to lug along in high gear at idle speed...should've got the original cam running right because that's what it was designed for.

Get valves adjusted "RIGHT" and forget generic fit-um-all directions.

Get a timing light so you can fine tune the engine. It's not just for setting initial timing. You can use it to watch the advance curve and see what's really going on. Can't do that by ear.

Get a good vacuum gauge and learn how to use it. That's old school tuning that does still work today.

Clay

Copy that.

[STEELCITYFIREBIRD]

Multi threads and problems....

What car?
What final gear is in this car?
and what first gear ratio.
Standard trans IIRC.


Very good advice Clay is advocating.
A 400 with those heads and cam wants to spin,
You need to put an excellent tune on it for good low rpm manners.

[ta man]

It is trickier to tune a 4 speed. You are going to have to work thru the tune from both timing and carb adjustments to find what works. It may be as simple as less vacuum advance, heavier springs to delay mechanical advance,a little more fuel etc. Its trickier with a manual transmission since there is a direct link to the engine.
Like has been suggested a "few" times get a timing light with a tach it will open your eyes to what actually is happening as the engine revs up. Plus when you make adjustments you can document your changes.

[Formulajones]

Being 227 @ .050 on a 110, in a 400 CI, it shouldn't be all that bad to get it dialed in. Just going to take some time finding the right timing curve and fuel mixture that makes the engine happy. Compression ratio plays a roll as to how well it will work and how much fiddling you'll need to do.

I run a 254 @ .050 on a 112 in a tiny 302 CI engine with a 4 speed. Pretty rambunctious cam for a little engine but it's dialed in and so docile on the street now you'd never know it. Wife drives it every day. Doesn't even have a bunch of gear out back, just 3.55's, and it'll loaf around town in 4th gear at 25 mph without complaint.