Roller or not to Roller

[Andy's Auto]

sNOMOBLR.

 

Here is my $.02.

 

 

The 781s with a little bowl work are great heads. Hydraulic roller? If you got the pockets, tear it up. Easier on the valvetrain and require less spring pressure to keep the valves from floating. Stroker? I have 3 496s and a 505. All required just a little trimming on the block area around #8 piston skirt area. Other than that it is your choice if you want to go internal or external balance. I like internal personally.

 

Even my weak low compression iron Merlin headed 496 went 12.0. My Bow Tie headed 496 in my 81 Malibu is running high 9s right now. And it rocks a 150 shot of NOS if needed on the street.

[wallaby]

To get back to the initial question, I have seen the computer dyno programs show about a 50 lbft gain just by going to roller cam. That's pretty substantial. You would be lucky to get that from any other mod, including heads. Running a flat tappet cam of similar lift & duration cuts you out of that gain potential.

If it were me, I'd go roller...but chosen by the experts that build them, and designed for the purpose you have in mind. You can add heads later if you want, or go all out by doing everything now. I'm not sure why your goal is rpm...most guys build for HP or torque. I'm one of those that builds with torque as my goal, and believe that is the way to get a fun street car that you can afford to drive. Stroker motors are so much fun because they are bigger, and have lots of torque...but they aren't too fond of high rpms.

[snomobeelr]

I think I have Rpms stuck in my head because she died off at 5800 and seemed like it she should have been going faster. So for some goofy reason I seem to be thinking if she tached up to 6200 to 6400 she would be better. I know goofy. So the 6400 isnt important what is is trying to get it right. So I know I still want the roller cam /lifters and rockers. I think I would rather do the stroker than the heads. I am assuming I cant just do somthing with Rods and pistons correct, has to be entire lower end.. What are high RPM's on a big block? 6500 and above?

[Dans '70 Z20]

Thanks, how long have you had the Sanderson's ? I pulled the heads off today and the Pistons are "L2399.030" when I google them they come up as TRW or Sealed Power Forged and block is 0.30 over.

 

Had them for a few years but car still not completed. LOL

 

But I know they have a full length header and a block hugger 3/4 length with 1 7/8" tubes that they claim fit on our cars. Call them to verify.

 

Dan

[Machtuck]

Sno, here's the deal

As others will attest, you can attain your goal with your current setup. A stout mechanical roller and a set of race rites ( brodix), will achieve this. Expect your power band to be around 3200-6800 rpms. This will be fine initially however, if you really beat on it, your stock rotating assembly is not going to acommodate this. Drivability and vacuum will be diminished.

As you can see, you begin to get yourself in a game of cat and mouse between your components. A forged bottom end will be needed for prolonged beatings. Also, those pistons are heavy. I used those many years ago on a 454 i had in a camaro. They are LS6 rebuilders and they are probably giving you the 9 to 1 that you said you had. If you are going to just re- ring these pistons and use them, You need to be very careful about your piston to valve clearance when upgrading to the hyd roller cam.

More 2 cents:

If you elect not to go the stroker route, lower your hp goal and concentrate on a nice street motor with lots of torque that will still be loads of fun and deliver years of reliability.

Bowl those 781's and stab a hyd roller in the mid to high 230's intake duration.

Check how far the pistons are in the cyl. ( probably around .025). If you are looking for more compression, you may need to omit decking the block for it. Again, those pistons are known for p to v issues. Mock it up and check. You may be able to skim .010- .015 off the deck.

Your decision for a roller is sound as bbc have been know for eating them. I personally have wiped two cams, smallblock 283 and pontiac 400. Alot of the woes of cam failure evolve from erroneous spring pressures and people tend to get lazy on the actual procedure. I have made cam break in day a national holiday at my household. I fill the radiator the night before and have a garden hose available. I use a test light to get the disributor dead nuts so it will fire right up. Fuel is place directly in the fuel bowl, and i sacrifice one small chicken with two hell marys. If you go the flat tappet route, follow the cam manufaturer's procedure. I like mechanical flat tappets just for the sound and because they're old school cool. A nice stout one will be good with your gear. Good luck Sno.

[Mike 57]

Funny how things snowball, and how willing we are to spend you money!

You have gotten some good ideas and answers.

If I were on a budget I would do the bottom end and cam, heads can be added at a later date.

Strokers, I love them. The more inches the more torque. I shift mine at 6500 or more. You can get a forged assembly for some pretty good prices. I think it would give you more bang for the buck than heads.

 

Have fun sorting it all out.

Just remember it your car and you can do whatever you want.

[snomobeelr]

So I pulled the camshaft out thinking I would be able to decifer the numbers. Curious to figure out what I has since I can not remember. Nope. If anyone has an Idea please let me know.. I am leaning to go with the roller cam and keep the 781's for now. I like the Idea of the stroker alot. Just not sure with the expense of the kit and having block machined for it. So depending on what the machinist says maybe try and boost the compresion. Maybe new rods and pistons. But I will need to have it rebalanced then. So here are the numbers from the Cam.

Thank You

 

182

p3

805-97

 

looking down the length of the cam it has

20

1581

d4

m

other side of it = CWC

[CrazyDavey]

all I can tell you Alan is the CWC is the core maker (CWC Textron in MI), they make a lot of cast OEM stuff as well as supply cores to the aftermarket.....