Cam gurus, I need advice

[smokie]

With the cam I have , comp recommends their 987 springs. Would I be better off going to a beehive spring? Will the spring locators I have work with them? I'm guessing they also make retainers for 10* locks that I currently have?

I'm thinking of going a little smaller on the cam, lift would be about the same, but I don't want to turn it 7k rpm. Honestly, about 6k is as hard as I want to turn it.

[Wetflow]

I'm thinking of going a little smaller on the cam, lift would be about the same, but I don't want to turn it 7k rpm. Honestly, about 6k is as hard as I want to turn it.

Why not let it sing? Especially if you're considering a modern spring?

7k RPM today is the 6k RPM of only 15-20 years ago.

[smokie]

It's got a scat "cast steel" crank it and I'm not sure what kind of rpm it can tolerate. I never minded turning a 327 or 350 up but the longer strokes kinda make me nervous. Also, I've never done it with a hydraulic cam, I've always ran solid flat tappet cams, this is my first hydraulic roller and I'm not sure how to control the valve train with bricks for lifters.

[skinny z]

With the cam I have , comp recommends their 987 springs. Would I be better off going to a beehive spring? Will the spring locators I have work with them? I'm guessing they also make retainers for 10* locks that I currently have?

I'm thinking of going a little smaller on the cam, lift would be about the same, but I don't want to turn it 7k rpm. Honestly, about 6k is as hard as I want to turn it.

Do you have a cam spec yet?
There's your RPM more or less.
My most accounts, and based on the nature of your build direction ( similar to my earlier scuttled 383 project), a spring like PAC's 1219 will serve to extend the RPM range over the 987. I'm pretty sure I can pull up a Spintron test that reflects that. Everything about the spring is different though. I'm using an I.D. locator in a 1.44" spring pocket although the spring itself is little more than an inch across the base. The retainers are tiny in comparison. I've moved up to a tool steel version which makes for about a 30% weight reduction over the conventional retainer.

[skinny z]

It's got a scat "cast steel" crank it and I'm not sure what kind of rpm it can tolerate. I never minded turning a 327 or 350 up but the longer strokes kinda make me nervous. Also, I've never done it with a hydraulic cam, I've always ran solid flat tappet cams, this is my first hydraulic roller and I'm not sure how to control the valve train with bricks for lifters.

With the beehive springs (COMPs 26918 or PACs 1219), and the tool steel retainers posted above, have reliable gone to 7k in a drag racing format. This is with COMPs short travel hydraulic roller which made a big difference over the OEM Gen 1 rollers.

[smokie]

My lifters are Lunati, I think they are the street hydraulic roller lifters. I'm not sure, but I doubt they are short travel. If I go this route, will I need to buy new spring seat locators or will the ones for the comp 987 springs work? Will my 10* locks work with beehive 10* retainers? I have no clue about beehives, never messed with them before. I don't know what will interchange between the regular springs and beehives.

Which pac spring should I go with, PACs 1218 or PACs 1219? There's a little difference between the two.

A 7k rpm 383 does sound like it would be a blast.

[skinny z]

My lifters are Lunati, I think they are the street hydraulic roller lifters. I'm not sure, but I doubt they are short travel. If I go this route, will I need to buy new spring seat locators or will the ones for the comp 987 springs work? Will my 10* locks work with beehive 10* retainers? I have no clue about beehives, never messed with them before. I don't know what will interchange between the regular springs and beehives.

Which pac spring should I go with, PACs 1218 or PACs 1219? There's a little difference between the two.

A 7k rpm 383 does sound like it would be a blast.

I've been looking a Lunati lifters and they look to be a solid choice.
The short travel (which the Lunati's are not) has some debate attached to it so I'll leave it at that.
But, when I see "street roller" I think of a cast lifter body as opposed to a machined tool steel body. We've found that the cast body tends to give up at higher RPMs. I never pushed the COMP equivalent (853) of the Lunati to that 7k RPM ceiling although I can say COMPs 15854 version, which happens to be the short ravel variety, is also a steel body. It may have have changed over the last decade and a half but that's what my research showed at the time. They were flawless until old age caught up with them.

As for the 987 and compatibility with PAC or COMP beehives. It's a different game altogether.
Different I.D. at the base. Different retainer at the top.
So locators needed as well as retainers.
As for locks, I've not looked into a 10° version. A quick look through Summit shows a Titanium version available....
I went with Crane's offset keepers as I needed to manipulate the installed height after the locators were in play.
I'd go with the 1219 PAC spring in your case. Or mine for that matter.
One engine was running an XFI profile lobe with some reasonably quick action and the somewhat stiffer spring was better suited. Lifts were under .580" via a 1.6 ratio rocker.

Anyway, no guru here but those are the experiences I can relate.

As for a 7k 383 and the cast steel crank? I suppose that depends.

https://www.summitracing.com/parts/cca-987-16 (springs)

https://www.summitracing.com/parts/cca-26918-16 (springs)

https://www.summitracing.com/parts/cca-4705-16 (locators 26918)

https://www.summitracing.com/parts/cca-774-16 (retainers 26918)

[smokie]

I've turned gm cast cranks pretty hard, but not with the longer stroke. I had built a large journal 327 with a cast 307 crank that I turned 7,500 rpm all the time. That little motor was a screamer. The scat crank is externally balanced and that worries me. I've seen plenty of cast gm 400 cranks break at the front of the crank snout.

An internally balanced 4340 crank would definitely make me more comfortable turning it up.

[skinny z]

I've seen plenty of cast gm 400 cranks break at the front of the crank snout.

An internally balanced 4340 crank would definitely make me more comfortable turning it up.

I've heard similar stories. I think a few of them were referencing the externally balanced 3.75" cast steel crank as well.

The internally balanced 4340 was part of the decision tree when working through the 383 project.

[CamKing]

My lifters are Lunati, I think they are the street hydraulic roller lifters.

Those are the Morel Street Performance lifters, and are made in Mexico.
They're fine with a mild hydr roller profile with moderate spring pressures.
I would not run them in any aggressive lobe profiles, or with heavy spring pressures.

[skinny z]

My lifters are Lunati, I think they are the street hydraulic roller lifters.

Those are the Morel Street Performance lifters, and are made in Mexico.
They're fine with a mild hydr roller profile with moderate spring pressures.
I would not run them in any aggressive lobe profiles, or with heavy spring pressures.

Curious Mike. Other than Johnson, who carries a US made roller lifter? Something that would take an aggressive profile and/or provide reasonable service life. Nothing spicy. 7k max. Maybe something along the lines of your EHR .360" lobes.

[smokie]

How long have they been made in Mexico? This set is about 7-8 years old, I just never used them until now. Are they suited for the cam I have or do I need to go with something else?

[CamKing]

How long have they been made in Mexico? This set is about 7-8 years old, I just never used them until now. Are they suited for the cam I have or do I need to go with something else?

Their Street Series has always been made in Mexico. That's why they're half the price of the normal Morel HR lifters.
They would be fine with your current cam.

[CamKing]

Curious Mike. Other than Johnson, who carries a US made roller lifter? Something that would take an aggressive profile and/or provide reasonable service life. Nothing spicy. 7k max. Maybe something along the lines of your EHR .360" lobes.

There's a few companies making private label HR lifters in the U.S. I don't know who all is carrying them.
Our XLR-8 HR lifters are made in the US, and that's what we would run with most of the EHR lobes. When you get above 7,000rpm or go to 1.8 rockers, then we recommend the Johnson lifters.

[skinny z]

Curious Mike. Other than Johnson, who carries a US made roller lifter? Something that would take an aggressive profile and/or provide reasonable service life. Nothing spicy. 7k max. Maybe something along the lines of your EHR .360" lobes.

There's a few companies making private label HR lifters in the U.S. I don't know who all is carrying them.
Our XLR-8 HR lifters are made in the US, and that's what we would run with most of the EHR lobes. When you get above 7,000rpm or go to 1.8 rockers, then we recommend the Johnson lifters.

Excellent!
Thanks for that Mike.