74 LS4-454

Ok, spoke to Lunati & Isky.
For the Lunati roller I need 135 lbs on the seat and 340-350 lbs Open.
The Isky springs already installed on my #215 heads are 135 lbs seat pressure and 350 lbs open pressure.
Both are saying that those springs are sufficient with the roller that I order earlier this AM.
I don't pretend to know and dont know all of the specifics pertaining to all of this but im learning. I ordered the voodoo cam listed in the previous post.
Hopefully everything will work out just fine...

63mako

This one?
http://www.lunatipower.com/Product.aspx?id=4538
Should work if you get your quench tight. I would have went a little bigger but it is your call. Good luck!

74 LS4-454

Yes, it is that one, and from what you mentioned in a previous post about the TH400 having a stock 2000 stall converter, I should be ok, since this cam works well with that converter.
I will take my chances, I really don't want anything radical, my whole intention was just getting something to run better than a stock LS4. I'm glad I'm going with a roller, and don't have to worry about break-in. I will read up on how to get my quench tight. The 215 heads are 100 cc's and I still have to take my other measurements. This has been a good learning experience, and will be more rewarding if everything works out.

Can't thank you guys enough for all of the info that has been posted in this thread. It is appreciated.................:c heers: Tom

illenema

Okay Time to get her built.

c6silver

Any updates ???

74 LS4-454

Been out at the 74 for a good part of the last two weeks.
Waiting on the cam and lifters. Carb is on the way back from Lars. Still a lot to do, not even thinking about the engine right now, as I am finishing up painting the frame. I won't make my target date, but still accomplishing a lot.
Of course it always takes longer than you think. .
Thanks for asking, will keep you posted.

74 LS4-454

Latest update...apparently Lunati is very busy, as my order just went in, they have to make the cam. May have it late next week. No problem, as putting the 74 back together is taking longer than expected....

And I have to rebuild my glass t-top for the 82 before I go back to work bext week...

badrad

This thread nearly went full circle. I like the Lunati cam that was picked, much more power potential within the constraints of the build. Tom, I couldn't find the ad but PM me and I'll take the cam/lifters.

Quench is the total number of compressed head gasket thickness and pistons to block deck measurement.

c6silver

Do they press on a cast iron distributor drive gear ?

74 LS4-454

Hello Jim, I did not post the ad yet, that is why you couldn't find it
I will send you a PM later, the cam and lifters are yours, I have to get some things done and run some errands before I can send you a PM.
Talk soon........................Tom


I did ask them about that and they said that the material that they use (can't remember the name) will accept any drive gear and have never had a problem with any of them getting destroyed. I will try to find out the name of what material is used and this time will write it down..
thanks for checking up.........

63mako

Austempered.

c6silver

It's actually austemperd ductile iron...which is ***** compared to a steel billet roller cam like Crane and Comp used to sell...it's like the difference between a cast vs a forged crank. Yuck. Do a Google search on austempered ductile iron roller cams and read the horror stories...FWIW.

c6silver

According to an article in "Engine Builder Magazine" (a magazine that is sent to machine shops and people in the engine rebuilding business), you have only two choices for a distributor gear with an austempered cam core...first is melonized or hardened, and second is composite (carbon fiber)...you CAN'T use an ordinary cast iron distributor gear, the gear on the cam will eat through it and put metal into your engine. I DON'T CARE what the Lunati tech idiot says...tread cautiously here SSROADSTER...buy a melonized gear.

c6silver

Another post says that the hardened steel roller lifter wheel will break down the austempered ductile iron cam core because it's a steel billet wheel riding on basically hardened cast iron...the two materials are not compatible. This is a cost cutting measure by cam companies to avoid paying for steel billet cores for their cams. Apparently they are following in the LS1/2/3/4/6/7/9 etc footsteps (GM uses austempered ductile iron for these cores), but GM made the cam core bigger in those engines, and who knows what they use for a wheel on the end of their OEM roller lifters...certainly NOT billet steel like an aftermarket lifter would most likely be made from.

74 LS4-454

this is the response I received.....


"The cam will be what we call a ‘SADI’ core. That stands for Specially Austempered Ductile Iron. We use them for a number of reasons, one of the main ones being they are compatible with any distributor gear.

As far as what you are talking about, there are cores available that are full steel billet or a steel billet with a cast iron gear attached on the end. The price goes up quite a bit, especially the second one, but the idea is you don’t have to run a bronze or some kind of special gear to be compatible with the steel billet if you get the cast gear attached.

I don’t know for sure what ‘name’ you are referring to but it’s one of two things. ‘Melonized’ distributor gears are what Chevrolet came up with when they started using steel hydraulic roller cams in factory stock motors. Look up melonized in the dictionary, it’s hilarious. The other term that is known out there is ‘everwear gears’. There are cores with that attached and there are distributor gears called that also. It’s just a trademarked name for heat treated iron gears which makes them compatible with steel. We carry a heat treated distributor gear that is the same idea. You shouldn’t need anything special with the core that yours will be on though."


Looks like more research on my end is needed.......

badrad

C6 brings up some good points, you don't want that cam core. I have an austempered roller I need to regrind because it has tracking marks in it (not on it but grooves). See if they offer a billet core with the cast iron gear, they usually aren't much more. The bronze/melonize gears require frequent inspections since they wear very fast comparatively.

c6silver

I would HATE to see SS throw money down the drain AND ruin his short block in the process...call CRANE CAMS and see if they still use steel billets. I know this is a giant PITA, but it will be worth it in the long run. This seems to be an industry wide problem right now (Comp is using austempered cores for some of their roller cams also), and a good friend of mine that races a '67 Buick with a solid roller cam CAN NOT find a billet blank ANYWHERE. His engine builder uses Jones Cams to grind all his cams to their own specs, and he's been hung up for about a year trying to just get a blank. This is a low 10 second 455 with aluminum heads, solid roller, 12 bolt 4.10s, Select TH400, Dominator, single plane intake, full weight (no fiberglass) car. It jerks the front wheels a foot in the air on the leave. For this year, he's lightening it, putting in a bigger cam and exhaust system, and dropping back to 3.90 gears to try to break into the 9s.

This austempered **** sux...and I haven't heard a PEEP from the car magazine guys, I had to hear it on here. I wonder why that is...would the advertisers pull dollars ???

74 LS4-454

I hear all of you, believe me.....I can get the steel billet from Lunati, if I am understanding them correctly. Even though they just shipped out the cam on Friday, I am going to refuse the delivery and I'm sure they can use it for stock and order the better one, I've gone this far so I will follow the advice given here....as mentioned, I don't want to ruin my short block.....so a change is in order.......

c6silver

Just to reiterate...get the steel billet core with the CAST IRON gear pressed on...YES it's the most expensive, but then you don't have to change distributor gears either...cast iron on cast iron...just like if it were a stock cam. Least problems this way.

ajrothm

SADI core will be fine.. All cam companies are using Sadi now.. Yes you can get billet cores from all of the cam companies too and it is definitely better... But not necessarily needed, especially on a HYD roller with 135 psi on the seat.

I just bought a custom HYD roller for a 396" from CStraub and its SADI. If it wasn't good, he wouldn't be using them..

That being said, I do have a billet core Isky in my 496" with 185lbs on the seat... In my 402 LS I have an off the shelf Comp and I believe its SADI... Definitely not billet.... Hell it may be pot metal or something not even be as good as SADI...lol


I would definitely recommend shimming the springs for a bit more then 135lbs/350lbs. After those springs are ran a few miles, you'll lose 10% pressure right off the bat... The valve train is heavy for a HYD roller BBC with long push rods etc etc... More pressure is definitely better then not enough.. I'd shoot for 150/375lbs at a minimum when fresh..