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468 Roller setup? What do I need?

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#21 ·
Z15CAM said:
We can't answer that unless you tell us what Piston & Static Compression you will be running.

That 270H-10 would be OK for a 9.1 Static 400 to 425Hp and the XM278H-12 is one fantastic Cam with a Static between 9.5 to say 10.2:1 producing close to 525Hp.

Buy their more Expensive Hydraulic lifter or better yet by OEM or Old Stock Crane, TRW, Clevite or Elgin HFT Lifters. The Comp Cams CCA-925-16 Springs should work just fine with either Cam - Course you will require 2" ARP Studs, ARP Poly Locks, Comp Cam 10 Degree Locks and Retainers and possible Crane Spacers if your heads have Valve rotators under the Exhaust Springs. Again I repeat Descent Roller rockers either Harland Sharp or Comp Pro Mags.

That Lunati Cam with that big 302 Advertized duration and 115 LSA looks more like a Blower Cam to me.

Suggest you go back and re-read what has been posted.

This is a 625Hp 7000rpm 10.25:1 460ci BBC in my 70Z - Totally over board and too expensive for Street and Cruising application where the much cheaper 500hp 10:1 XM278H-12 is more practicable and dependable.
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M21 to 3.31:1 12 Bolt Posi - What can I say she's a Road Warrior that can burn a Tank of Gas, all the Rubber Off and go nowhere in 20 minutes but still a great HWY Cruiser at 2400rpm.
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Ron,

Can you list your motor's combo. 625HP is pretty stout for a 10:1 454.
 
#22 · (Edited)
Yes them Speed Pro L2465F60's with a 25.7 cc Dome will do just fine with them 118cc 781 heads (CC them - It's Important) and should give approx a 10.3:1 Static Compression in a 4.31 Bore with a .018" Steel Head Gasket yielding an 8.13:1 DCR with the CCA-XM278H-12 Cam & 925 Springs - NICE Combination - Believe me that cam is a real torquer through the RPM range & sounds mean.

Vince: The motor started as a 73 LS4 out of a Chevelle. Has Eagle Forged Rotating assembly with L2465F30 Pistons under Worked 781 Heads giving me a 10.25:1 Static. I run a Lunati 502A1LUN (278/290 244/255 @ .050" .630"/.630" 112 LSA) with Everwear Gear Cam & CCA-933 Springs (215/525 lbs installed at 1.85"), Crower Hippo Lifters, giving me an 8.12:1 DCR. Morroso 7qt Sidekick Pan with a full length Milidon Diamond Stripper Windage Tray. Donovan Cam Gear Drive and BHJ SFI 7.25" Balancer. ISKY 7/16" Push Rod's. Manley Severe Duty Pro Flow Valves, Titanium Retainers, Lash Caps, Carter Mechanical Fuel Pump, slightly modified NASCAR Holley 80511-1 830 Annullar Booster 4 Corner Carb sitting on an Edelbrock RPM Air Gap - Ignition is Mallory Hyfire VI with a Vacuum Advance Unilite and Remote Timing Retard Control in the Glove Box. Comp Cam Pro Mag Roller Rockers, ARP Studs and a Jomar Girdle - She spins 7000+rpm without issues on Pump Gas, Accel Extreme Heat 9000 Series Plug Wires. I run ESSO XD-3 EXTRA CI-4 Plus 15w-40 Industrial Oil in the mill with a NAPA DANA/WIX LONG OIL FILTER PN: 51060- Muncie Gear Oil: Marvelube GL-1 80w-90 (Straight Mineral Oil) Hope this is Good Enough. Lost a 66 4 Bolt 396 years ago which I regret. Spilled my Guts - LOL

Apart from the Machining Costs you don't even want to consider the Price of the Parts. I have Buddy's Speed & Machine Shops & do work for them occasionally when it comes to Building Specialty Mills for Clients.

Considering the Expense for another 100 Hp and another 800rpm, It's not any more Fun on the Street then running that CCA-XM278H-12 combination which is thousands of Dollars Less. You're not going to catch me but you will come close.
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Yes that's a Magnetic Breakerless Mallory you see in the PIC but I use a UniLite on the Street.
Alu Heads would definitely be a weight saving asset but I rather like the Stock Appearance especially when I hear comments about my Mill.

The Tappet Adjustment has remain Rock Solid for 4 years now; X-Fingers.

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Logan: Just get that 72 with them round tail Lights on the Road - There's too many 1st GENS out there :eek:
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As I say my ride is a Road Warrior, not a Drag Racer. She will smoke BF P295N50 Comp T/A's about the full length of the 1/4.
Probably a 12 sec car as is but I launch from 40mph+ and bury the 150mph speed-o in a flash.

All on Pump Gas. Really you don't to see my grill in your rear view because it won't be there after you blink.

Click on my Flickr Link below - You will Note that I'm not only one H*ll of a Muscle Car Mechanic but more of a Motorcyclists & Love my Family.
 
Discussion starter · #23 ·
Hey Ron,

Just to clarify something, the XM278H-12 cam that I have been looking at and linked to on my previous posts says it is a SBC cam on summit's site. Does small block vs BB not matter, (I am assuming it does). Because the cams I picked other than that one are SBC. also, are the other cams I picked out (if they will work) any better or worse than the XM278H-12?

Thanks again!
 
Discussion starter · #25 ·
Aahh I see...

the lift on that cam is 0.564 int./0.567 exh.

I thought going over .510 would cause problems... I will have to research all over if this is not the case, please let me know.
 
#26 ·
I thought going over .510 would cause problems...
Click to expand...
Where you getting this BS? I've run .563" lift in a SFT 327 without issues.

BBC OEM heads will require Longer Valves or some shave the Valve Guides down (Not recommended) when lifts get over .670"
 
#28 ·
what ever combination you do choose--do the machine work and get it done right--i would go scat crank since they are reasonable and less work to balance --balance the assembly--get the compression you want by zero decking then pistons you need for the compression you desire, zero decking will give more power verses a same compression motor thats not--spend the time in bowl blending --well worth it just alot of buckets of beer and time
 
#29 ·
Z15CAM said:
Vince: The motor started as a 73 LS4 out of a Chevelle. Has Eagle Forged Rotating assembly with L2465F30 Pistons under Worked 781 Heads giving me a 10.25:1 Static. I run a Lunati 502A1LUN (278/290 244/255 @ .050" .630"/.630" 112 LSA) with Everwear Gear Cam & CCA-933 Springs (215/525 lbs installed at 1.85"), Crower Hippo Lifters, giving me an 8.12:1 DCR. Morroso 7qt Sidekick Pan with a full length Milidon Diamond Stripper Windage Tray. Donovan Cam Gear Drive and BHJ SFI 7.25" Balancer. ISKY 7/16" Push Rod's. Manley Severe Duty Pro Flow Valves, Titanium Retainers, Lash Caps, Carter Mechanical Fuel Pump, slightly modified NASCAR Holley 80511-1 830 Annullar Booster 4 Corner Carb sitting on an Edelbrock RPM Air Gap - Ignition is Mallory Hyfire VI with a Vacuum Advance Unilite and Remote Timing Retard Control in the Glove Box. Comp Cam Pro Mag Roller Rockers, ARP Studs and a Jomar Girdle - She spins 7000+rpm without issues on Pump Gas, Accel Extreme Heat 9000 Series Plug Wires. I run ESSO XD-3 EXTRA CI-4 Plus 15w-40 Industrial Oil in the mill with a NAPA DANA/WIX LONG OIL FILTER PN: 51060- Muncie Gear Oil: Marvelube GL-1 80w-90 (Straight Mineral Oil) Hope this is Good Enough. Lost a 66 4 Bolt 396 years ago which I regret. Spilled my Guts - LOLQUOTE]

Thanks Ron, a very nice and effective!
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#30 · (Edited)
OK that 270H-10 with .510" lift is OK with 9:1 - But what are your Intentions? Change Pistons out for the Speed Pro L2456F-60's to get 10.3:1 - by all means and your still within HFT Range with the XM278H-12 with an 8.2 DCR to run pump Gas without having to Deck running them 781's with a .018" Steel Shim Head Gasket & .044" Quench. That 112LSA give's Higher Vacuum - Broader Torque Range through the RPM Scale through to 6300rpm at which Hydraulic Lifters fail whether they are HFT or HR in a BBC. If anything I would tend to go SFT but then you need a Forged Crank and more Expense to Beef the Mill to get beyond 6300rpm.

I can't count the # of MKIV's I've built but from my experience a Stock 7.5 to 8:1 :1 works best with between a 266 to 268H-10 - 9:1 Static between 268 to 270H-10 producing 390 to 420Hp respectively below 5800rpm. Now Enter the Forged Piston 10:2 to 10.3:1 Cast crank Mill with the XM278H-12 and strong Valve Train - Your at 6300rpm with excellent vacuum, putting out 500Hp with humongous Torque and great dependability with a Holley 750/Edelbrock RPM. Other then Forged Pistons and beefed Valve train it's the Biggest Bang for the Buck.

About the only thing you could option is to 0-Deck and run a .038" Composite Head Gasket. This would allow you to bolt on Lighter Alu-Heads without pulling the Mill; but if you intend to go beyond 6300rpm you will require a Forged Crank and run either a SFT for 575Hp or SR Cam for 600+hp which cost thousands more and for what - Another 100Hp and 800rpm which you can't use on the street without ending up behind bars.

Whatever you do "DO NOT over Cam". Patrick Kelley's DCR Calculator is an excellent guide for Street Driven Mills on Pump Gas. Learn to use it.

I might add - Always buy .020 or .030" over size rings and Gap them, using feeler gauges irregardless of piston to bore clearances, to fit each Cylinder to Minimum Specs.

More advice - Don't Dance with me & Wish I knew what you have learned in this forum when I started.

PS: Vince - I replaced the Trunnion Exhaust Rotators with .140" Crane Spacers to Load CCA-933-16 Springs on the 781's.
 
#31 ·
Good info Z15.

Makes me want to pull out my low mileage 454 I have in my shed, and throw in some new pistons and the XM278 cam, for some fun street driving. :)

How does that 278 sound at idle?
 
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#32 · (Edited)
How does that 278 sound at idle?
Click to expand...
Hear at Comp Cams Site:http://www.compcams.com/base/multimedia/soundbytes/compcams278.mp3

It really has the Best Exhaust Note of most Cams I've heard. Don't let that Extreme Marine designation hinder you for the cams ability to perform on the Street. I will choose that Cam for between 9.5 to 10.3:1 Static application over most SFT and Expensive SR Setups as I say: "Forget about HR for Mid Cube Inch MKIV's as they like to Rev over 6000rpm." and that's one HFT Cam that can do it - I'm not a Comp Cams advocate by any means as I personally run UD Harold Lunati SR Profiles at great expense.

You have to understand that Aftermarket Mfgr's design their products to work with OEM Specs - Once you change these Specs like 0-Decking you may change the Height of the Cylinder Head but more specific the Height of the Valve Train in relation to the Mills Efficiency.


DECKING:
Generally MK1V pistons are .025" down in the Bore Measured at TDC across the Wrist Pin Axis. Now add that .018" Steel Shim Gasket and you got a .043" Quench. You want a Quench between .034 & .044" (Prevents PING). If you can afford to 0-Deck, that is mill .022" to .025" off the Decks, which is an average distance, and run a .038" Composite Gasket you would have a Quench between .038 to .041". 0-Decking & running a Composite Gasket allows you to run Alu-Heads in the Future and Keep that all Important Quench. You can't use a Steel Shim Gasket with Alu-Heads. O-Decking and using a .038" Composite Gasket you probably can use a Stock Length Push Rod and OEM Valve Train Ratios (Always Clay your Valve to Piston Clearance if you intend to run more then a 280 Duration - If not for a Basic Reading for future cam changes .080" Intake and .100 is Exh is Safe - you can probably shave .020" of this if your mill is right on specs - and you don't rub the Valve Reliefs) as the Valve will set within OEM Specs in regards to Valve to Piston clearances for the Mfgr's Cam Profile. Once you go over .670 Lift with OEM Heads on a MKIV - Considering your not using an aftermarket modified head you may require a longer valve before it bangs against the top of the guides. Duration Vs DCR (Cylinder Head Pressure, depended on Fuel Octane) is all about Over Camming - Not Lift.

Then consider "Lift Vs Spring Pressures" can cause premature Valve Train failure and that boils down to how strong & lube the Valve Train to function with moving Heavy Weights at Higher Pressures as the RPM Increases for a more Efficient & Reliable Wind Mill.

It's no wonder Modern Engines are 4 Valve DOHC. The design was there back in the 20's but the Metal Composition was not available.
 
#33 ·
Wow,Ron. Thanks for sharing and being so straightforward with your info. This is the best engine info I have read on big blocks for the street. I have one in the wings for my 68 and I believe I will be re-reading this thread more than a few times.
 
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Z15CAM
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