decision on a roller cam for the Big Block

[alaskanbowtie]

So I bought this long block Marine application 454 for 400.00 new on the crate . Now I'm going to put a roller cam in it and maybe another set of heads . So I looked at the Comp site and they have a few that look decent but not sure on what to expect on the bottom end with a big block . So K5 spec's are as follows :
78' , 10/12 bolts with 4:56 gears
Locked front and rear
36" tires
TH350 with mild stall .

Now the engine will have stock marine application bottom end and
probably a set or Merlin cast iron heads and dual plain intake and headers going through 2.5" duals all the way out . So I want lots of bottom end but also want it to spin up good and not fall on it's face at 4000 rpms . So is going with a retro fit roller with around 218' intake and 224' exhaust at .050" going to be good or a little big ? Will I notice a drop in bottom end performance . Should I go with the next step down which is like 212 & 218 ? it will also have a set of goood roller rockers on the top end too . All info and experience appreciated .

 

[sled_dog]

Go down a step. For crawling or bottom end the lowest one is usually the better choice. I am tempted to take a step up on my roller cam in my 383 but am on the edge. With Merlin heads and that cam(the 212/218) you will have a good deal of power throughout the powerband, though don't expect a 6000 RPM monster. What is my big suggestion? Stand back and watch the fireworks in that 12 bolt

 

[mojo-jojo]

I like this





[font=Times New Roman, Times, serif]454 XETREME 4X4 DESCRIPTION[/font]

[font=Times New Roman, Times, serif]Sallee Chevrolet’s 454 XTREME 4x4

[/font][font=Times New Roman, Times, serif]Brand New 454 XTREME 4x4 Engine
A Sallee Chevrolet exclusive engine.[/font]
​

[font=Times New Roman, Times, serif]P/N SC454X
[/font][font=Times New Roman, Times, serif]This engine is designed for carburetor equipped vehicles, 4x4 trucks, RV’s, Tow trucks. We wanted a engine that would produce huge torque #s at very low RPM levels. We started with a proven package, the Goodwrench 454; this engine has the peanut style, high torque heads. The camshaft was next, so we contacted Comp Cams to discuss our new engine combination we told them what we wanted and they were excited to help, the words flat tappet came up and we said no way we wanted a hydraulic roller cam. So with many questions going back and forth over the phone Comp Cams and Sallee Chevrolet Research and Development Personnel decided on a cam grind.[/font][font=Times New Roman, Times, serif] The Sallee Chevrolet Engine crew took over installing the roller cam. We decided on the peanut port #8017 Weiand intake manifold (Edelbrock #2161 can be used also). We decided we needed to do some valve train upgrades, so we upgraded the 5/16 push rods to 3/8 heavy duty push rods with the guide plates to match. We also installed ARP rocker studs, then we installed GM long slot stamp steal 1.7 rocker arms. With this combination this valve train will be adjustable. With the engine all assembled we were ready to put it on the dyno for testing. When the first test pulls where finished the race shop manger brought me the figures, I was completely amazed the 454 had over 400 Ft. lbs. of torque below 1500 RPM, so this is how the new 454 combination became alive and available to you.


[/font][font=Times New Roman, Times, serif]Note: [/font][font=Times New Roman, Times, serif]This engine is designed for non computer vehicles. This engine will accept mechanical fuel pump.[/font]

[font=Times New Roman, Times, serif]COMP Cams Xtreme 4X4 Cams[/font]​

[font=Times New Roman, Times, serif]Newest Design in their Application Specific Camshafts
Increases HP In 4-Wheel Drives & Sport Utility Vehicles
Increases Usable Torque in 4-Wheel Drives & Sport Utility Vehicles
Accelerated Valve Timing Events & Optimized Cylinder Pressure[/font]

[font=Times New Roman, Times, serif] 454 XTREME 4X4 SPECIFICATIONS[/font]

[font=Times New Roman, Times, serif]Displacement: 7.4 liter (454 cubic inches)[/font][font=Times New Roman, Times, serif]Horsepower: 316 @ 3500 RPM*[/font][font=Times New Roman, Times, serif]Block: Gen 6 cast iron, four bolt main.[/font][font=Times New Roman, Times, serif]Bore/Stroke: 4.250” x 4.00”[/font][font=Times New Roman, Times, serif]Compression: 8:1[/font][font=Times New Roman, Times, serif]Timing: 4° BT DC, 36° @ 3500 RPM[/font][font=Times New Roman, Times, serif]Pistons: Cast Aluminum[/font][font=Times New Roman, Times, serif]Balancer: 8” HD[/font][font=Times New Roman, Times, serif]Connecting Rods: Forged Steel.[/font][font=Times New Roman, Times, serif]Camshaft: Comp Cams Hyd. Roller[/font][font=Times New Roman, Times, serif]Valve Lift (Intake/Exhaust): 511”/511”[/font][font=Times New Roman, Times, serif]Duration (Intake/Exhaust): 206°/212°[/font][font=Times New Roman, Times, serif]Valve Diameter (Intake/Exhaust): 2.07”/1.72”[/font][font=Times New Roman, Times, serif]Valave Springs: Stock 91-95 454 CK Pickups[/font][font=Times New Roman, Times, serif]Cylinder Heads: #125528888 Cast Iron Round Port[/font][font=Times New Roman, Times, serif]Spark Plugs: CR43TS .035 Gap[/font][font=Times New Roman, Times, serif]Max. RPM: 5,000 RPM[/font][font=Times New Roman, Times, serif]Fuel: Unleaded[/font][font=Times New Roman, Times, serif]Crankshaft: Nodular cast iron. One Piece Rear Seal[/font][font=Times New Roman, Times, serif]Push Rods: 3/8 HD, 1010 steel, 3/8 Guide Plates[/font][font=Times New Roman, Times, serif]Torque: 400 lbs. @ 1439 RPM*, 423 lbs. @ 1900 RPM*, 432 lbs. @ 2100 RPM*, 447 lbs. @ 2400 RPM*, 462 lbs. @ 3000 RPM*, 475 lbs. @ 3500 RPM*
Dyno Graph and Sheet: Click here for the page showing both of these.
Intake Manifold: Aluminum Dual Pattern (8017 Weiand or 2161 Edelbrock)
Rocker Arms: HD Long Slot 1.7 Ratio Adjustable Valve Train
Distributor: (Optional) GM HEI or MSD, must use a hardened distributor gear. With the roller camshaft, also, a new gear must be used. Also, coat gear with moly lube. Please ask our PARTS SALESMAN for more information.
Carburetor: (Optional) We recommend an electric choke style, do to the fact that there is no heat cross over passage in the heads. Carburetor choice's sometimes depends on vehicle application. Edelbrock #1407 Performer series or a #1904 Q-Jet will work. Recalibration may be required on any choice.
[/font][font=Times New Roman, Times, serif]WARRANTY: 12 months parts only. Warranty must be performed at Sallee Chevrolet. No warranty on marine ingines. Some restrictions may apply due to abuse or neglect.[/font][font=Times New Roman, Times, serif]*Note: Tested on our Dyno with 2-1/8” headers. Figures wll be much lower with cast iron exhaust manifolds.[/font]

 

[dyeager535]

IMO unless you are racing, and the BBC retrofit roller stuff is better designed than SBC stuff, forget the roller cam. Too much expense, reduced reliability (according to Crane) amd just not enough gain.

Of course, if the block is ready for a roller from the factory, have at it.

 

[alaskanbowtie]

roller cam

I want to do the roller for both h.p. and the issue with cam break in in the big blocks , they are prone to cam issue's because of the poor oiling characteristics . So anyone else running a roller with some comments .