Is solid roller lifter loading really the highest at idle?

540 RAT · Post by **540 RAT** » Thu Oct 16, 2008 4:07 pm

CamKing wrote:
540 RAT wrote:Something else for us to consider in the pursuit of lifter longevity. We seem to be between a rock and a hard place on the lash issue...........
Not if you go with a rev-kit.
It'll make the clearance ramp do what it's supposed to do, and your lifters will live longer.
Of course, it may cause the rollers on your rocker arms to fail sooner.

I have not attempted to make a rev-kit work myself, but as I recall, Wolf has said you can't really make a rev-kit fit on a BBC using a Dart Big M block along with lifters such as Isky's or Crowers. If anyone knows of a rev-kit that will work on this type setup, let's hear about it.

new engine builder · Post by **new engine builder** » Thu Oct 16, 2008 5:31 pm

You guys seem to have forgotten more than I will ever know.
Can you please tell me what is an "inverted roller cam".
Was this a trademark name?
Or is this an actual technical term used to describe the cam??

Post by **CamKing** » Thu Oct 16, 2008 5:35 pm

n2omike wrote: Comp's Xtreme Energy street cams are advertised to have lift ramps 'almost' as fast as their race cams, but slower closing ramps for less noise, and less pounding on the valvetrain and seats.

Since it's the opening ramp that causes the pounding on the lifter, that's just pure genius at work.

The slower closing ramp will help the seats, but won't have any effect on lifter life.

Post by **CamKing** » Thu Oct 16, 2008 5:44 pm

new engine builder wrote:You guys seem to have forgotten more than I will ever know.
Can you please tell me what is an "inverted roller cam".
Was this a trademark name?
Or is this an actual technical term used to describe the cam??

"inverted roller cam"
"Inverse Radius Roller"
"I.R. Roller cam"

These are names to describe a roller cam profile that has an inverse radius(concave) on the opening and closing flanks of the profile.
Every Roller cam We've made since 1979 has been an Inverse Radius cam. Designing the profiles like we do allows us to get the area under the curve we want without having to increase the ramp speeds.
When comparing one of our IR cams to our competitors cam with the same area, our will have a much slower velocity at the seat.

new engine builder · Post by **new engine builder** » Thu Oct 16, 2008 6:13 pm

CamKing wrote:
new engine builder wrote:You guys seem to have forgotten more than I will ever know.
Can you please tell me what is an "inverted roller cam".
Was this a trademark name?
Or is this an actual technical term used to describe the cam??
"inverted roller cam"
"Inverse Radius Roller"
"I.R. Roller cam"

These are names to describe a roller cam profile that has an inverse radius(concave) on the opening and closing flanks of the profile.
Every Roller cam We've made since 1979 has been an Inverse Radius cam. Designing the profiles like we do allows us to get the area under the curve we want without having to increase the ramp speeds.
When comparing one of our IR cams to our competitors cam with the same area, our will have a much slower velocity at the seat.

Thats why I am on here.
I have learned a lot the past few weeks.
Now if I could only retain all of it.

Thanks.

ausbullet · Post by **ausbullet** » Thu Oct 16, 2008 6:22 pm

I have not attempted to make a rev-kit work myself, but as I recall, Wolf has said you can't really make a rev-kit fit on a BBC using a Dart Big M block along with lifters such as Isky's or Crowers. If anyone knows of a rev-kit that will work on this type setup, let's hear about it.[/quote]

I run a Crower rev kit with Isky EZX's and a Dart BigM,
it needs some fitting and machining, but it can be done.

Steve

540 RAT · Post by **540 RAT** » Thu Oct 16, 2008 7:22 pm

ausbullet wrote: I run a Crower rev kit with Isky EZX's and a Dart BigM,
it needs some fitting and machining, but it can be done.
Steve

Any chance of some pictures and/or some details as to the machining and fitting required. It would be nice to know what's in store before spending the money and tearing the motor down.

ausbullet · Post by **ausbullet** » Thu Oct 16, 2008 9:22 pm

[quote="540 RAT
Any chance of some pictures and/or some details as to the machining and fitting required. It would be nice to know what's in store before spending the money and tearing the motor down.[/quote]

Crower kit 82001
Isky lifters 372-96-RH
Grind rev kit plates to fit 'around' head stud bosses on block,
Machine the spring holes in the plates deeper, shorten and relieve the lifter spring locators.
I forget the exact numbers, you have to make up for the .300" taller lifters.
This just fits with 3/8" pushrods.
I have run this set up for 2 1/2 seasons, 2 seasons with the Needle roller Isky Red-Zones and 1/2 a season with the EZ X rebuilt Red Zones.

540 RAT · Post by **540 RAT** » Fri Oct 17, 2008 11:16 am

ausbullet wrote: Crower kit 82001
Isky lifters 372-96-RH
Grind rev kit plates to fit 'around' head stud bosses on block,
Machine the spring holes in the plates deeper, shorten and relieve the lifter spring locators.
I forget the exact numbers, you have to make up for the .300" taller lifters.
This just fits with 3/8" pushrods.
I have run this set up for 2 1/2 seasons, 2 seasons with the Needle roller Isky Red-Zones and 1/2 a season with the EZ X rebuilt Red Zones.

Thanks for the info. Did you have a failure with your Isky needle-type Redzones, in spite of the Rev-Kit? This is an important question regarding whether or not the rev-kit idea really offers any true benefit in general, and for Big Blocks in particular. If the Redzones did fail, is that what prompted you to switch to the EZX upgrade?

desoto30 · Post by **desoto30** » Fri Oct 17, 2008 2:17 pm

ausbullet wrote:[quote="540 RAT
Any chance of some pictures and/or some details as to the machining and fitting required. It would be nice to know what's in store before spending the money and tearing the motor down.

Crower kit 82001
Isky lifters 372-96-RH
Grind rev kit plates to fit 'around' head stud bosses on block,
Machine the spring holes in the plates deeper, shorten and relieve the lifter spring locators.
I forget the exact numbers, you have to make up for the .300" taller lifters.
This just fits with 3/8" pushrods.
I have run this set up for 2 1/2 seasons, 2 seasons with the Needle roller Isky Red-Zones and 1/2 a season with the EZ X rebuilt Red Zones.[/quote]

I have a similar combo going together & have 82001 on the way
Do you what/know how much difference there is between the Crower 66291H16 & the Isky 372-96-RH the reason I bought 82001 rev kit was to circumvent as many fitment issues as possible.

ausbullet · Post by **ausbullet** » Sun Oct 19, 2008 7:22 pm

[quote="540 RATI have run this set up for 2 1/2 seasons, 2 seasons with the Needle roller Isky Red-Zones and 1/2 a season with the EZ X rebuilt Red Zones.

Thanks for the info. Did you have a failure with your Isky needle-type Redzones, in spite of the Rev-Kit? This is an important question regarding whether or not the rev-kit idea really offers any true benefit in general, and for Big Blocks in particular. If the Redzones did fail, is that what prompted you to switch to the EZX upgrade?

Yes the cam was 'spalled' on 1 lobe the roller pin was badly worn on that lifter and the link bar was broken on that lifter. What happened first ????
I believe the roller pin or the cam spalling 1st and the link bar last. NB: This was still the original cam.

There was another lifter brand was recommended and tried, unsuccessfully.

The Isky's were refitted with 1 replacement lifter and link bar, to finish out the season.

The motor was rebuilt as a 565 and the lifters were updated to the EZ X rollers.

To clarify this further, the motor was originally fitted with Crower Severe Duty roller lifters that had 5 roller pins failing just short of 1 season, picked by increase on lash on those valves. The Isky Red Zones were fitted, the motor was still in the boat, without the rev kit and ran 1/2 a season before it was refreshed and the rev kit installed.
NB: the Crower lifters were NOT the HIPPO style.

I season is 20 hours race time and another 8 hours of low load running.

ausbullet · Post by **ausbullet** » Sun Oct 19, 2008 7:26 pm

I have a similar combo going together & have 82001 on the way
Do you what/know how much difference there is between the Crower 66291H16 & the Isky 372-96-RH the reason I bought 82001 rev kit was to circumvent as many fitment issues as possible.[/quote

The Isky's are a 'full body' design, there are not cut away behind the link bar attachment point.

Wolfplace · Post by **Wolfplace** » Sun Oct 19, 2008 7:57 pm

ausbullet wrote:
I have a similar combo going together & have 82001 on the way
Do you what/know how much difference there is between the Crower 66291H16 & the Isky 372-96-RH the reason I bought 82001 rev kit was to circumvent as many fitment issues as possible.[/quote
The Isky's are a 'full body' design, there are not cut away behind the link bar attachment point.

=
They have both, the cut away is an option

Thank you for the info on the rev kit, it is good to know the Crower plates can be modified to fit.

ausbullet · Post by **ausbullet** » Sun Oct 19, 2008 8:37 pm

Wolfplace wrote:
ausbullet wrote: The Isky's are a 'full body' design, there are not cut away behind the link bar attachment point.
=
They have both, the cut away is an option

Thank you for the info on the rev kit, it is good to know the Crower plates can be modified to fit.

Mike,

I was refering to the 372-96-RH above.
I still haven't purchased the new set of EZ X's yet, still qualifing there performance.
Up to 19 hours total, after this weekend.
Yes they are looking the goods and I will keep you in mind to order the new set.
A bit of work to fit/adapt the kit, but, I believe the rev kit helps.

Steve

Wolfplace · Post by **Wolfplace** » Sun Oct 19, 2008 8:52 pm

ausbullet wrote:
Wolfplace wrote: =
They have both, the cut away is an option

Thank you for the info on the rev kit, it is good to know the Crower plates can be modified to fit.
Mike,

I was refering to the 372-96-RH above.
I still haven't purchased the new set of EZ X's yet, still qualifing there performance.
Up to 19 hours total, after this weekend.
Yes they are looking the goods and I will keep you in mind to order the new set.
A bit of work to fit/adapt the kit, but, I believe the rev kit helps.

Steve

=
Hi Steve,
Thought that was you but I have sent a few sets to folks your way now so I wasn't sure

I agree, a rev kit is a good idea to keep the rollers in contact with the lobes, just makes sense to me although I have a number of BB's roaming around without them, none with them & your info is appreciated as I was not aware the Crower plate could be modified to clear the bosses in the Dart blocks

When you need a set just give me a hollar, I will be glad to help

Thanks,