Roller cam newbie Once you start going down the rabbit hole!

[Bronze Barracuda]

Alright, it seems I have a heck of a lot to learn. Valve stem positive seals - Do we need to machine heads for this? Valve springs for camshafts, what pushes the need for springs, the duration, lift or rpm.?
I am looking at getting a roller cam with these specs, DUR @ .050 218INT/224EXH Intake lift .535 Exhaust lift .531 (1.5 Ratio). So I will need a spring upgrade I was going to get Melling 466463 the specs say coil bind is at 1.025. So .535 X 1.5 = .8025 lift for coil bind.? (But the way of my thinking is if the lift is .535 with 1.5 Rockers then is that not the max lift? & if so a coil bind of 1.025 seems EXTREME!) Am I reading/doing this correct? Or are the other specs like installed load & height (112 @ 1.687) & open load and height (290 @ 1.187) factor into the math of figuring out maximum lift for these springs? Also will I need positive valve stem seals. Will I need to machine the heads for these valve springs? I was also looking at Hughes 1110P springs. Anyone using the Hughes or Melling springs I mentioned? If so what lift are you running and did you need to do any additional machine work for these springs? Thanks guys and gals.

 

[Siksty7 Dart 270]

I have the Hughes springs in my Magnum heads. Cam is 212/220 @.050 .485/.506 @ 1.5 rocker arm ratio. No machining required and they work as they should.

 

[Bronze Barracuda]

I have the Hughes springs in my Magnum heads. Cam is 212/220 @.050 .485/.506 @ 1.5 rocker arm ratio. No machining required and they work as they should.

Thanks. I've never thought much about a springs coil bind before. But with a lift of .535 I figured I'd look into a springs specs a little deeper. This Comp cam seems to have an interesting profile. Such a high lift with the duration, and it's advertised working range which is 1400-to 5500 rpm.

 

[TrailBeast]

Thanks. I've never thought much about a springs coil bind before. But with a lift of .535 I figured I'd look into a springs specs a little deeper. This Comp cam seems to have an interesting profile. Such a high lift with the duration, and it's advertised working range which is 1400-to 5500 rpm.

I am also running the Hughes 1110 springs and positive seals.
214/224 @.512 lift with 1.6 rockers roller cam and factory Magnum lifters with factory rockers.
The locks and retainers are from Hughes and are from a V6 that give more retainer to stem seal clearance.
I don’t remember the part number.

EQ 318b heads no machining for the seals or springs.

 

[Bewy]

Step into the 21st century & think about beehive/conical springs. Less spring tension needed, easier on the valve train. Positive type valve stem seals needed, not the junk umbrella seals...

 

[PROSTOCKTOM]

The reason a roller cam requires more spring pressure than other types of cams is you have to keep the rollers on the lifters planted on the cam lobes.

Selecting the correct valve springs and installed height is not a guessing game. If you don't know or understand what you're doing you need to ask the advice of the cam company.

A stable valve train or the lack of will kill an engine quickly. Personally most guys over look the finer points of the measurements and the geometry.


.535" lift with a 1.5 ratio rocker is only a .3567" lift on the lobe. You divide it, not multiple it.

Those spring pressures you mentioned above do not have enough pressure for any type of roller cam and running a low cost single spring is just asking for trouble.

Running a low cost dual spring setup will save the engine should you break one of the coils.


Tom

 

[Bronze Barracuda]

Lucky for me that camshaft wasn't able to ship till early March. So I cancelled the order. But I'm curious, how would you go about determining the correct installed height, for a given camshaft? The lift of that cam, had me a little nervous. Now I'm considering something lot less tame.

Howards Cams

711915-12​

Duration at .050 is, 221 int. and 225 exh.
Lift is .474 into. .500 exh.
The Hughes springs 1110P I listed was recommended by Hughes website for a few of their roller cams?

This cam in particular (from Hughes) which has similar profile to the Howards Cams recommends the 1110P Springs?

https://www.hughesengines.com/Index...&level2=SHlkcmF1bGljIFJvbGxlcg==&partid=30210

Thanks for the help though. I'm going to call summit tomorrow and see what springs they'd recommend for the Howards Cams
711915-12

 

[TrailBeast]

Lucky for me that camshaft wasn't able to ship till early March. So I cancelled the order. But I'm curious, how would you go about determining the correct installed height, for a given camshaft? The lift of that cam, had me a little nervous. Now I'm considering something lot less tame.

Howards Cams

711915-12​

Duration at .050 is, 221 int. and 225 exh.
Lift is .474 into. .500 exh.
The Hughes springs 1110P I listed was recommended by Hughes website for a few of their roller cams?

This cam in particular (from Hughes) which has similar profile to the Howards Cams recommends the 1110P Springs?

https://www.hughesengines.com/Index...&level2=SHlkcmF1bGljIFJvbGxlcg==&partid=30210

Thanks for the help though. I'm going to call summit tomorrow and see what springs they'd recommend for the Howards Cams
711915-12

FYI, I had my stock 5.9 cam reground a whole lot cheaper with the specs I posted above.
It was less than 200, and I had to get longer pushrods.
Oregon cam grinders did it.

 

[Bronze Barracuda]

FYI, I had my stock 5.9 cam reground a whole lot cheaper with the specs I posted above.
It was less than 200, and I had to get longer pushrods.
Oregon cam grinders did it.

I gave them a call but they didn't have any cores, I recycled mine years back. I'm assuming I'd need a cam from a roller LA. I'll be keeping my eye out for some. My local pick and pull has a bunch of magnum engines. Oldest being 1998. 1998 seems like it was yesterday.

 

[TrailBeast]

I gave them a call but they didn't have any cores, I recycled mine years back. I'm assuming I'd need a cam from a roller LA. I'll be keeping my eye out for some. My local pick and pull has a bunch of magnum engines. Oldest being 1998. 1998 seems like it was yesterday.

I think it would be a lot simpler to get a Magnum core and add the mechanical fuel pump kit if you want to run a mechanical pump.

I don’t know though, you could probably find a stock Magnum cam on here that someone pulled out.
Then have them send it directly to Oregon for you.

Maybe?

 

[Siksty7 Dart 270]

I gave them a call but they didn't have any cores, I recycled mine years back. I'm assuming I'd need a cam from a roller LA. I'll be keeping my eye out for some. My local pick and pull has a bunch of magnum engines. Oldest being 1998. 1998 seems like it was yesterday.

You could use a Magnum cam and add the snout extension and fuel pump eccentric available from Hughes Engines (Mancini Racing might have them too). Or run an electric fuel pump.

 

[Demonracer]

Place an ad in the "Wanted" section and see who comes up with one. I'll bet someone here has a core, or one they have pulled to go bigger.

 

[Dale Davies]

Alright, it seems I have a heck of a lot to learn. Valve stem positive seals - Do we need to machine heads for this? Valve springs for camshafts, what pushes the need for springs, the duration, lift or rpm.?
I am looking at getting a roller cam with these specs, DUR @ .050 218INT/224EXH Intake lift .535 Exhaust lift .531 (1.5 Ratio). So I will need a spring upgrade I was going to get Melling 466463 the specs say coil bind is at 1.025. So .535 X 1.5 = .8025 lift for coil bind.? (But the way of my thinking is if the lift is .535 with 1.5 Rockers then is that not the max lift? & if so a coil bind of 1.025 seems EXTREME!) Am I reading/doing this correct? Or are the other specs like installed load & height (112 @ 1.687) & open load and height (290 @ 1.187) factor into the math of figuring out maximum lift for these springs? Also will I need positive valve stem seals. Will I need to machine the heads for these valve springs? I was also looking at Hughes 1110P springs. Anyone using the Hughes or Melling springs I mentioned? If so what lift are you running and did you need to do any additional machine work for these springs? Thanks guys and gals.

OK, one at a time;
1: positive valve seals. Generally yes you need to machine the tops of the guides to fit the seals. When using a higher lift cam you also need to check retainer to seal clearance and may need to machine a bit off the height of the guide.
2: Springs: lift and RPM are the determining factors on new springs. It is a matter of inertia of the valvetrain components. Now duration does also affect this, but getting high lift requires lifting the lifter, valve and everything between at a higher rate. Of course higher RPM increases that rate also, imparting more momentum into the parts.
3: Lift. The lift of the lifter × rocker ratio gives the design valve lift. Bottom line.
4: Coil bind. This is a spec the spring manufacturer gives or you can measure. It is the length of the spring when all the coils are compressed on eachother and it can not be compressed more. Not something you want in a running engine.
5: Installed height. This is the length of the spring as installed and ready to run. The installed height gives the seat load the spring imparts to hold the valve on the seat.
6: The stuff that is also important. Installed height minus the valve lift gives the spring length at max lift.
OK, so if you have an installed height of 1.8", you subtract the 0.535" lift to get 1.265". So if your coil bind height is 1.025", you have 0.245" extra room. Springs work better to stay out of surge if run closer to the coil bind spec. For conventional springs probably 0.050" to 0.750". Beehive springs can be run down to 0.025" to 0.030".
You have to check retainer to seal clearance at max lift. This is easier to do with checking springs. You can get a couple at your local hardware store. Use these instead of the valve springs with the retainer and keepers installed. Use a dial indicator on the edge of the retainer to measure max lift. It should be the same as listed on the cam card. Using the numbers you have supplied the intake lift should read 0.535". You should then be able to push the valve open at least 0.050" before the retainer touches the seal.
I hope this clears up the situation.
Also remember you have to check piston to valve clearance on any new build. 0.080" minimum on the intake and 0.100" minimum on the exhaust. Strips on modeling clay in 1/4" diameter strips across an intake and exhaust valve with the engine turned through two complete revolutions and remove the head. You can do it without a head gasket and just snug a couple of bolts on the cylinder being checked. When you put the gasket in the clearance will only increase.

 

[Bronze Barracuda]

OK, one at a time;
1: positive valve seals. Generally yes you need to machine the tops of the guides to fit the seals. When using a higher lift cam you also need to check retainer to seal clearance and may need to machine a bit off the height of the guide.
2: Springs: lift and RPM are the determining factors on new springs. It is a matter of inertia of the valvetrain components. Now duration does also affect this, but getting high lift requires lifting the lifter, valve and everything between at a higher rate. Of course higher RPM increases that rate also, imparting more momentum into the parts.
3: Lift. The lift of the lifter × rocker ratio gives the design valve lift. Bottom line.
4: Coil bind. This is a spec the spring manufacturer gives or you can measure. It is the length of the spring when all the coils are compressed on eachother and it can not be compressed more. Not something you want in a running engine.
5: Installed height. This is the length of the spring as installed and ready to run. The installed height gives the seat load the spring imparts to hold the valve on the seat.
6: The stuff that is also important. Installed height minus the valve lift gives the spring length at max lift.
OK, so if you have an installed height of 1.8", you subtract the 0.535" lift to get 1.265". So if your coil bind height is 1.025", you have 0.245" extra room. Springs work better to stay out of surge if run closer to the coil bind spec. For conventional springs probably 0.050" to 0.750". Beehive springs can be run down to 0.025" to 0.030".
You have to check retainer to seal clearance at max lift. This is easier to do with checking springs. You can get a couple at your local hardware store. Use these instead of the valve springs with the retainer and keepers installed. Use a dial indicator on the edge of the retainer to measure max lift. It should be the same as listed on the cam card. Using the numbers you have supplied the intake lift should read 0.535". You should then be able to push the valve open at least 0.050" before the retainer touches the seal.
I hope this clears up the situation.
Also remember you have to check piston to valve clearance on any new build. 0.080" minimum on the intake and 0.100" minimum on the exhaust. Strips on modeling clay in 1/4" diameter strips across an intake and exhaust valve with the engine turned through two complete revolutions and remove the head. You can do it without a head gasket and just snug a couple of bolts on the cylinder being checked. When you put the gasket in the clearance will only increase.

OK, one at a time;
1: positive valve seals. Generally yes you need to machine the tops of the guides to fit the seals. When using a higher lift cam you also need to check retainer to seal clearance and may need to machine a bit off the height of the guide.
2: Springs: lift and RPM are the determining factors on new springs. It is a matter of inertia of the valvetrain components. Now duration does also affect this, but getting high lift requires lifting the lifter, valve and everything between at a higher rate. Of course higher RPM increases that rate also, imparting more momentum into the parts.
3: Lift. The lift of the lifter × rocker ratio gives the design valve lift. Bottom line.
4: Coil bind. This is a spec the spring manufacturer gives or you can measure. It is the length of the spring when all the coils are compressed on eachother and it can not be compressed more. Not something you want in a running engine.
5: Installed height. This is the length of the spring as installed and ready to run. The installed height gives the seat load the spring imparts to hold the valve on the seat.
6: The stuff that is also important. Installed height minus the valve lift gives the spring length at max lift.
OK, so if you have an installed height of 1.8", you subtract the 0.535" lift to get 1.265". So if your coil bind height is 1.025", you have 0.245" extra room. Springs work better to stay out of surge if run closer to the coil bind spec. For conventional springs probably 0.050" to 0.750". Beehive springs can be run down to 0.025" to 0.030".
You have to check retainer to seal clearance at max lift. This is easier to do with checking springs. You can get a couple at your local hardware store. Use these instead of the valve springs with the retainer and keepers installed. Use a dial indicator on the edge of the retainer to measure max lift. It should be the same as listed on the cam card. Using the numbers you have supplied the intake lift should read 0.535". You should then be able to push the valve open at least 0.050" before the retainer touches the seal.
I hope this clears up the situation.
Also remember you have to check piston to valve clearance on any new build. 0.080" minimum on the intake and 0.100" minimum on the exhaust. Strips on modeling clay in 1/4" diameter strips across an intake and exhaust valve with the engine turned through two complete revolutions and remove the head. You can do it without a head gasket and just snug a couple of bolts on the cylinder being checked. When you put the gasket in the clearance will only increase.

Thanks a lot. Lots of great information.