BBC balancer & valve spring question

[scot74]

Hey Guys,

I'm yanking the motor out of my boat to do a little maintenance. It's a 468ci with 990 heads, 10 to 1 compression, hydraulic roller cam, from crane cams, part number 139741. Cam specs are as follows, advertised duration 296 intake, 304 exhaust, .610 intake lift, and .632 exhaust with 1.7 ratio rockers. Max rpm I've seen is 6200 rpm a few years ago.

Two Questions

One- I'm installing a new oil pan that I purchased from a fellow member here and I was thinking about upgrading my stock non sfi approved harmonic balancer. I was looking on ebay. The only ones that are posted look like chinese knock offs or are made by Profession Products. They are sfi approved, but are not named brand, (fluid dampner, ATI, Rattler,etc.). Do I need to purchase name brand stuff or will these work? What do you guys run or recommend? Which ones should I steer clear of?

Two- I'll also be replacing my valve springs that I suspect are wearing out and are 4 years old. The crane cam card calls for 132 lbs. @ 1.906 closed and 414 lbs. @ 1.306 open. I'm currently running comp cams 924-16 which are only 112 lbs. @ 1.900 closed and 355 lbs. @ 1.200 open. I've ordered a micrometer to measure my valve spring height. I will have that measure met in about one week. I'd like to see some more rpm's and I suspect I'm experiencing valve float because I'm down to only 5800 rpm's. I called comp cams and they recommended they're new beehive valve springs and titanium retainers. Do you think these changes will give me a couple hundred more rpm's? Is this stuff worth the money? Has anybody run thse "beehive springs" and if so, what has been your experiance. Should I stick with tried and true dual springs?

Please let me know your thoughts...

[BradP]

ATI is the chit!;)

[Wannabe]

The ATI balancer is the belle of the ball. But for your application it may be more money than you need. Professional products are making some pretty good stuff. It is all overseas mass produced stuff, but the better of the overseas junk. I have run their products on a few items so far with no trouble at all. I have also heard decent stuff about their balancers.
Word from a dyno operator at a large engine facility says their intakes are good for more power over the compatable Edelbrock, Holley, Merlin, or Weiand, for standard Chevy stuff. That company tries to talk people in to the Professional Products intakes, but most customers will not, and end up buying the brand name stuff.
Also look around for guys that run hydraulic rollers in racing applications with success. Getting them to run in the upper rpms usually requires the right lifters and the right oil. These babies do not rpm like the catalogs state that they do.
I did speak to a large race engine builder that says oil can be the difference in 800 rpm on the dyno with the lifters. Some 12 dollar a quart Joe Gibbs oil. But only one grade of the Gibbs stuff. Go figure? Too much testing for me. I just run solid roller and check the valves every 12th time to the lake.
Good luck and let us know how it goes.

[GR8WHITE]

The ATI balancer is the belle of the ball. But for your application it may be more money than you need. Professional products are making some pretty good stuff. It is all overseas mass produced stuff, but the better of the overseas junk. I have run their products on a few items so far with no trouble at all. I have also heard decent stuff about their balancers.
Word from a dyno operator at a large engine facility says their intakes are good for more power over the compatable Edelbrock, Holley, Merlin, or Weiand, for standard Chevy stuff. That company tries to talk people in to the Professional Products intakes, but most customers will not, and end up buying the brand name stuff.
Also look around for guys that run hydraulic rollers in racing applications with success. Getting them to run in the upper rpms usually requires the right lifters and the right oil. These babies do not rpm like the catalogs state that they do.
I did speak to a large race engine builder that says oil can be the difference in 800 rpm on the dyno with the lifters. Some 12 dollar a quart Joe Gibbs oil. But only one grade of the Gibbs stuff. Go figure? Too much testing for me. I just run solid roller and check the valves every 12th time to the lake.
Good luck and let us know how it goes.

yeah i saw some of the professional products intakes on the net and was curious of the quality. i come from building mostly imports and some of the knock off companies have equal quality of the name brands that they copy, but for the most part they look good in the picture and when you get it and look at it, it looks like someone cast the thing in a sandbox in their back yard, :D

[Moneypit]

Unless you use your boat ahellofalot,:eek: I doubt your springs have gone away. If they have, run away from the brand:mad:.......132# closed aint gonna see a whole lot of RPM..........MP

[wagspe208]

Those pressures are ridiculously low for a hyd roller cam.
What is your lash (well, preload)? Seat pressure should be 150 or so. Open..around 400 ish.
Wags

[RiverRacer]

Yeah, 132 is way low hell I run 150 on my flat tappet!. The beehives are supposed to be good but they are expensive, I would just get a set of "K Motion" springs, they'll last a long time!..

[Carnivalride]

Got to agree with everybody on the valve springs, roller lifters are heavy and the advertised 132# seat pressure seems awful light for an rpm deal. I'm running 145lbs on my flat tappet so I would think you'd be a lot higher if you were looking for 6500rpm +.

Is that 112lbs at 1.900" on your current springs a typo? :confused:

If your switching balancers (especially if its externally balanced) you might consider having your machine shop respin the rotating assembly to check the balance.

[wagspe208]

You said hydraulic rollers, right?
Beehive springs..hell on a big block, you have room for a normal spring. Titanium retainers for a 6500 rpm piece are not necessary. If you just want them because they are cool, great. Not necessary at all, though.
I assume you have rotator eliminators on the heads?
Wags

[scot74]

The preasures I stated are not a typo. The comp cams springs I'm currently running are recommended by comp cams and are sold as a kit for the previous comp cam I ran before switching to the bigger crane cam. The original comp cam was around .540 lift. I threw in the new crane cam a few years ago assuming the springs would be roughly the same.

I know, I know, I assumed and I now know that it makes a ass of me and you. Ha Ha

Why do you guys think crane cams would recommend such low preasures of 132 lbs. closed and 414 lbs. open? Shouldn't I follow their recommendations? Please help, I'm confused!!!!

I have eliminated the rotators on the heads.

If I remember correctly, I set the lash/preload at 1/2 turn past zero lash at the base of the cam. Is this correct? I remember seeing a thread on the old website regarding this issue and I don't mean to stir the pot again, or get into a discussion of which order to set the valves. I would appreciate your recommendations regarding just the lash/preload.

I now want to make the situation right and appreciate everybody's input.

Scott

[Carnivalride]

Hey Guys,

hydraulic roller cam, from crane cams, part number 139741. Cam specs are as follows, advertised duration 296 intake, 304 exhaust, .610 intake lift, and .632 exhaust with 1.7 ratio rockers. Max rpm I've seen is 6200 rpm a few years ago.The crane cam card calls for 132 lbs. @ 1.906 closed and 414 lbs. @ 1.306 open. I'm currently running comp cams 924-16 which are only 112 lbs. @ 1.900 closed and 355 lbs. @ 1.200 open.
Please let me know your thoughts...

Ok first off I can't find 139741 for a BBC on the Crane site, not saying its not what you have but I didn't find it.

However I found this for your 296/304, 610/632 hyd roller (139021)

I see them recommending a 99896 spring for this and a couple sizes above and below it. 150lbs @ 1.90" and 466lbs @ 1.290"

http://www.cranecams.com/?show=browseParts&lvl=2&prt=5&Vehicle_Type=Auto&Cylinders=8&Engine_Make=CHEVROLET&Year=1982&Engine_Size=396-454%20C.I.&partNumber=139021&partType=camshaft

[RiverRacer]

I couldn't find that number either, but 150lbs is good that's what I use on my solid flat tappet and I have 669/648 lift and I ran it 7500 no problems!..

[scot74]

I've attached a copy of the cam card. I feel a little foolish because I just noticed on the cam card it tells me the exact part number of the spring I need to purchase. It's exactly what Carnivalride recommended. I'm sorry to waste your guys time, and I do appreciate your efforts in helping me. Happy boating all...

Scott

[Carnivalride]

I've attached a copy of the cam card. I feel a little foolish because I just noticed on the cam card it tells me the exact part number of the spring I need to purchase. It's exactly what Carnivalride recommended. I'm sorry to waste your guys time, and I do appreciate your efforts in helping me. Happy boating all...

Scott

No need to feel foolish, you asked a question and we were just trying to help. Thats kinda how it works on this forum people seem to try and help out. Maybe next time you can be the one helping out. But from the spring pressures you have to the ones Crane recommends I bet you'll see a difference. Good luck! :cool:

[RiverRacer]

A while back I talked to Crane about their spring recommended pressures, asked why they are so low, they said it was a liability thing with flat tappet cams, for a while they had a lot of cams come back wiped out on breakin by people that don't know what they're doing, so they decided to drop the recommended pressures. My question was were the springs capable of more pressure, they said no problem after breakin just step it up 20lbs!.. Just like this one, 132 is not enough!..

http://www.v-driveboat.com/vweb/attachment.php?attachmentid=180&d=1208494672

[scot74]

Thanks guys, you've been a tremendous help to me!

[wagspe208]

In the last couple of years cam manufacturers have realized they can increase seat pressure on hydraulic roller cams more than they previously thought, or had recommended.
.540 springs on a .6?? lift cam. Are yuou sure you did not run into coil bind and bend pushrods (just slightly?)
Valve float occurs when the closing ramp of the cam closes quickly. The valve hits the seat and bounces back off the seat. With a big block intake valve weight, and low spring pressure this is more likely. It also beats the hell out of seats and valve faces.
Up your pressures with the Crane recommended springs, steel retainers (I'd just use 10 degree stuff for what you are doing), check for retainer to seal (guide) clearance issues, and run the hell out of it.
Wags

[RiverRacer]

Yeah, and if you want to get the most from a hydraulic roller cam, use a solid roller lifter it really wakes it up!...