Valve springs

d.j. moordigian said:
James,

1. Why is the "bypass hole " plugged in the block? I do it in my race Chevy's, but
why here. Does it have a thermostat? My race stuff have "blanking sleeves", no
thermostats.

2. Yep...3 & 4 are sure "wet"! When you get the pistons out, I'd look at the rings,
are they lined up?

3. I think Mike hit it on the head @ 8.5 with 86cc in the head, plus the 1/8"
bore! I'm sure the head was calculated with a 3 7/8" hole...not 4".

4. I think the "quench" is OK. If the rings are lined up....I'd be looking at the
timing/distributor which will cause this problem. Find some one with a Dist. machine
too check the lobe spacing. What kind of Dist.? Every engine I build...I run the Dist.

5. I'd also like too see photos of the rod bearings...especially the rod side.

Dudley
Click to expand...
I don't know why these are plugged. This is a motor from H&H but I don't know if they did all the mods.
 
BILL WILLIAMSON said:
James,
As a side note, wondering, with occasional sticking valves, wonder if a 1/8" spring spacer could be squeeked in above the spring with the head on? Some old springs are really soft. A friend increased his top speed from 51 MPH to 65 MPH by merely replacing his stock springs with NEW stock springs to eliminate valve float. Bill W.
Click to expand...

If i may ask? How does one tell if they are suffering from valve float?
 
Look for discrete wear marks on the closing side of the lobe where the lifter will hit if lofting or bouncing.
 
Today I installed a Stipe IB330 cam with .003 oversize bearings. This is the way to go if there is any significant wear on the center bearing. This cam fits the block just right and should take flex out of the equation. Tomorrow I will do a valve job on the block and grind the valves while I let one cool after I pour the bearings. Then I am going to pull the pistons and measure them for one side being taller than the other. I measured the block and there is only about .004 difference from one side to the other. Going to give it a light hone and new rings after checking the end gap. At .125 over, there is not much that can be done about wear except new rings.
 
PC/SR sent me some springs. Here is what I found.

I finally got the springs measured yesterday. The one I have from Snyder's is 50# at 2 3/8" compressed. The 2 you sent both came out at 49# at the same compression so, the current modern GYP springs are about the same and probably made by the same manufacturer but, are a little low in pressure than suggested. I didn't try them with a spacer but they should be at about 70# with a 1/4" spacer on top. I think adding a 1/4" spacer would be good on a performance engine but, for the street I would stay with a 1/8" or less.

I have come to the conclusion that the problem with this motor is the lack of oil in the valve chamber. The engine is full pressure so, all the oil is routed away through the filter and then to the bearings. There is not much way for oil to get to the valve chamber. It uses a V8 pump so the top is closed and no oil can pass. The pan is drilled in the tray so there is no oil to splash and mist the chamber even if it could get in it. There are no holes in the floor of the chamber for mist to come up through like a T or B engine. I think without this oil, the valves don't have the normal cushion that dampens sound and lubricates the stems and guides properly. More opinions? I can post pictures and will gladly since this is my first pressure motor and will likely be the last. If you want to know where it came from and my opinions about pressure, just ask.
 
PC/SR said:
Check that the bores are true perpendicular. Had a similiar problem, front of pistons higher, the machinist that corrected it said the prior guy's table was not true.
Click to expand...
I put the empty block on the mill yesterday and found the block measures 11.489 on one end and 11.491 on the other. There is +.004 difference from the front to the rear on one side and -.003 on the other side. The 11.491 end is flat but there is .0035 dish at the distributor hole. I will deck the block and cut the piston tops about .025, no more. The holes are square with the deck.
 
Do the gears show signs of oil starvation, is there signs of recent wear on the cam thrust button, the rods will throw oil past the bearings, the cam bearing will drool on the gear

I have been thinking on the valve springs, and will add this thought, the original valve spring seat pressures work for stock weight valves, and keepers.

stock ford valve and keeper --102 grams
modern 1.5 dia valve and keeper --133 grams
modern large intake valve and keeper--148 grams

so a modern replacement valve has about 30% more weight, the oversize intake about 45% more weight, with the added inerta of more weight you would need a higher percentage increase in spring---just to have the same performance as original parts, lifter weight changes,and cam changes also are factors. ---I am still gathering information to try and come up with more exact figures, but it is obvious that moderen valves will not be an improvement in performance with stock springs.
 
All stock springs that I have ever measured are less than 40#. I recommend 40# on a stock-grind cam, for better cooling of the valve. Performance cams are another story, 60# on a mild grind and as much as 90# on a flathead race engine. For those higher than 60# I use Isky V8 springs and make a spacer as they are a shorter spring.
 
Kurt in NJ said:
Do the gears show signs of oil starvation, is there signs of recent wear on the cam thrust button, the rods will throw oil past the bearings, the cam bearing will drool on the gear

I have been thinking on the valve springs, and will add this thought, the original valve spring seat pressures work for stock weight valves, and keepers.

stock ford valve and keeper --102 grams
modern 1.5 dia valve and keeper --133 grams
modern large intake valve and keeper--148 grams

so a modern replacement valve has about 30% more weight, the oversize intake about 45% more weight, with the added inerta of more weight you would need a higher percentage increase in spring---just to have the same performance as original parts, lifter weight changes,and cam changes also are factors. ---I am still gathering information to try and come up with more exact figures, but it is obvious that moderen valves will not be an improvement in performance with stock springs.
Click to expand...
The first aluminum gear was worn according to the customer. There is no way the rods can sling any oil since the dipper tray has holes drilled into the bottom of each trough. I don't even see any way oil can get into the tray since the pump is routed through the rod and main bearings and the excess is dumped out the drain tube. I may have to route some oil into the tray and replace the tray with an original not modified and drill 2 holes in the bottom of the valve chamber like a Model T or a Model B so the resulting mist can lube the valve train. As of right now I don't see any or much oil getting to the chamber to oil the cam or valves. There was some oil in the chamber when I took the cover off but it was not much. I believe the push rods and valve stem contact points need a cushion of oil to be as quiet as needed. Opinions?:confused:
 
d.j. moordigian said:
James,

1. Why is the "bypass hole " plugged in the block? I do it in my race Chevy's, but
why here. Does it have a thermostat? My race stuff have "blanking sleeves", no
thermostats.
Click to expand...
I don't know why they plugged these steam holes since the head doesn't have them and plugging them would have been an exercise in futility.
 
With all of the discussion of heights and pressures changed by the use of spacers I think it should be clarified whether these dimensions are with the stock type guide with shoulder or the often used solid straight guide with no shoulder. I'm assuming the spacers and spring rates discussed are added to the stock guide with shoulder.
 
The old volvo engine with a fibre timing gear had a small nozzle spraying on the gears, perehaps a small tube can be added off one of the bearing feeds, just a small .030,.040 hole to pis on the gears
 
Hey James,
'holes in dipper tray'..going to replace! I'm thinking that in 'pressurized' engine..the rod 'dippers' are usually not needed and REMOVED and that dipper hole is usually plugged (to reroute pressure from drilled crank, so that replacing dipper tray will not accomplish what you want i.e..- splashing...no?
 
If the crank is cross-drilled to the rod throws and pressure fed, there will be a constant spray mist of escape oil from both sides of each rod throw bearing as the crank rotates. This is more effective than dippers, as it works at both very low rpm that doesn't pressurize a dipper, and above the rpm where dippers will blow the tray dry (~3500 rpm). There is absolutely no need to revert to a solid dipper tray, it is better off with drain holes as a windage tray.

The valve chamber floor holes found in a B will permit some crankcase spray to migrate up, but rather poorly. It was not uncommon to make those holes way bigger in dirt track engines. The valves were relatively quiet because the much larger mushroom end stock valves and the big surface on stock non-adjustable lifters spread out the contact pressure, resulting in a slower crush of whatever oil mist or film was introduced into the lifter gap when that cam lobe was on it's heel. Modern small ended valves will definitely make more of a click unless the ends are relatively flooded with oil. Exhaust valves rely on a constant wet oil splash or feed to dissipate heat, both from the end of the guide in the chamber, and from the extending valve stem within the spring.

IMHO, the best way to positively oil the valves in an positively pressurized A or B engine with no open feed to a lifter tray in the valve chamber is with the use of a spray bar. That bar (tube) can be brazed to the inside of the valve cover. The cover on a B can cross-drilled to supply the spray bar from the oil runner at the bottom. Only 4 tiny holes, drill size 72 or 74, one pointing at the center of each exhaust valve spring will be plenty. They will actually squirt more of a solid stream than spray. That stream will be intermittently interrupted and broken into a coarse spray by hitting the moving exhaust spring. You will have direct exhaust valve cooling, oversplash to the adjacent intake valves, and, the forward overspray from the front one will also serve to oil the cam gear if the base of the valve chamber is drilled for direct drainage.

FWIW, I believe the B side-cover with filter made by Stipe employs a spray bar. I have never personally seen one of the Stipe setups so I do not know how many holes, what size, or what direction he uses.
 
MikeK said:
If the crank is cross-drilled to the rod throws and pressure fed, there will be a constant spray mist of escape oil from both sides of each rod throw bearing as the crank rotates. This is more effective than dippers, as it works at both very low rpm that doesn't pressurize a dipper, and above the rpm where dippers will blow the tray dry (~3500 rpm). There is absolutely no need to revert to a solid dipper tray, it is better off with drain holes as a windage tray.

The valve chamber floor holes found in a B will permit some crankcase spray to migrate up, but rather poorly. It was not uncommon to make those holes way bigger in dirt track engines. The valves were relatively quiet because the much larger mushroom end stock valves and the big surface on stock non-adjustable lifters spread out the contact pressure, resulting in a slower crush of whatever oil mist or film was introduced into the lifter gap when that cam lobe was on it's heel. Modern small ended valves will definitely make more of a click unless the ends are relatively flooded with oil. Exhaust valves rely on a constant wet oil splash or feed to dissipate heat, both from the end of the guide in the chamber, and from the extending valve stem within the spring.

IMHO, the best way to positively oil the valves in an positively pressurized A or B engine with no open feed to a lifter tray in the valve chamber is with the use of a spray bar. That bar (tube) can be brazed to the inside of the valve cover. The cover on a B can cross-drilled to supply the spray bar from the oil runner at the bottom. Only 4 tiny holes, drill size 72 or 74, one pointing at the center of each exhaust valve spring will be plenty. They will actually squirt more of a solid stream than spray. That stream will be intermittently interrupted and broken into a coarse spray by hitting the moving exhaust spring. You will have direct exhaust valve cooling, oversplash to the adjacent intake valves, and, the forward overspray from the front one will also serve to oil the cam gear if the base of the valve chamber is drilled for direct drainage.

FWIW, I believe the B side-cover with filter made by Stipe employs a spray bar. I have never personally seen one of the Stipe setups so I do not know how many holes, what size, or what direction he uses.
Click to expand...
Unfortunately Mike, this is an A engine so I would have to drill the tubes that transfer the oil to the mains which in turn feed the rods. I don't see any way of drilling the tubes to direct oil properly and the tubes are epoxied in so not removable. I have wondered if a small groove in the side of the oil pump top would allow enough oil to fill the chamber but then how to dump the excess.
 
hardtimes said:
Hey James,
'holes in dipper tray'..going to replace! I'm thinking that in 'pressurized' engine..the rod 'dippers' are usually not needed and REMOVED and that dipper hole is usually plugged (to reroute pressure from drilled crank, so that replacing dipper tray will not accomplish what you want i.e..- splashing...no?
Click to expand...
The rods don't have dippers and are H&H H beam rods manufactured for inserts. I just don't see how to get a sufficient amount of oil in the valve chamber without getting an excess and causing a reverse problem. I don't see any need for the dipper tray in it's current form except as a windage tray to keep the oil from sloshing forward and rearward during acceleration and stopping.
 
James Rogers said:
Unfortunately Mike, this is an A engine so I would have to drill the tubes that transfer the oil to the mains which in turn feed the rods. I don't see any way of drilling the tubes to direct oil properly and the tubes are epoxied in so not removable. I have wondered if a small groove in the side of the oil pump top would allow enough oil to fill the chamber but then how to dump the excess.
Click to expand...


I don't quite understand the 'dump excess' part- it would overflow the dam as normal.

James, Do you have a picture of the epoxied-in-place pressure plumbing? I see no reason why you can't add a tiny hole or bleed line to just flood the chamber. Are the end bearings of the cam also pressure fed? A 3/32 hole would provide quite a chamber flood even at idle, without excessively dropping the running pressure. Especially with that big pump.

Here is a picture of a pressure A block now on my bench, also with epoxied feeds. The main line, which follows the cylinders behind the valves, was epoxied in first. Then small tubes were fitted into the elbows at the ends to feed the cam bearings.

Just because your tubing is epoxied in place shouldn't stop you from adding a tiny bleed line or hole to flood the chamber. I was thinking about drilling the valve chamber floor of this block for drainage and adding nozzles to squirt the exhaust valves from the rear. I really want to get rid of the flooded chamber! I'll add another 1/8" tube with a swaged 0.020 hole to squirt the cam gear. Please excuse the spots of flash rust. It's been sitting two months, I haven't been feeling well.
PressureOilManifold.jpg
 
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