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How many of you guys run them out here? I'm looking at one for my next upgrade in my K5. I'm not realty worried about the life because I don't really drive it that much, more of a play toy. I'm gonna bump up compression as well.
Engine specs as it sits right now
Holley 750dp
Huricane single plane intake
990 heads w/ 2.25/1.88
.060 over forged pistons
9.5:1
Cast crank
Thumb rods
Here's the cam I'm thinking....
11-611-5 - Puller & Mud Race Mechanical Flat Tappet Camshafts
Imho... the only real problem with'em is that the oils aren't made to support the loading. So you need to use an oil that can handle that load.
But why?? Why not use a roller cam that reduces the friction and is easier on the timing chain for instance?
Since you aren't using the ride daily, if it wipes a lobe or two ( and it's been known to happen almost instantly) I guess it won't be such a bother except for all the fine metal particles that'll be passing around in the oil... and lodge into the main and rod bearings...
It's your money / choice.. I'll be curious what you decide and how it works out.
Price of a roller cam is a lot more. That's why I was looking at the mechanical series instead.
Seen too many flat tappet cams go bad.....If you lose a lobe and the particles off the cam wipe out the crank, rod, main, and cam bearings, then how much money did the flat tappet cam save you?????
You can do the flat tappet---you just need to use Brad Penn or Joe Gibbs oil
Personally, if I were forced to use a flat tappet cam, I'd rather do the flat tappet solid than I would a flat tappet hydraulic.
You can purchase solid lifters today that have a small 0.012" hole EDM'd in the crown that delivers pressurized oil directly to the cam lobe. You can't do that with a hydraulic lifter.
http://www.jegs.com/i/COMP-Cams/249/...oductId=753217
You can however, use a tool to cut a groove into the hydraulic lifter bore that will deliver pressurized oil directly to the cam lobe.
http://www.summitracing.com/parts/cc...FY9eQgodoGQAHQ
As far as the cam you posted a link to, note that Comp advises a minimum 11.0:1 static compression ratio for that stick. At 9.5:1 SCR, the intake valve would close too late to trap enough air/fuel mixture to make a good BANG. This would result in the motor being (as one of my buddies used to say) "a weak-suck operation". At 9.5:1, you would want a lobe that closes the intake valve at around 35 degrees after bottom dead center @0.050" tappet lift. Be careful when comparing solid cams to hydraulic cams. Most solids are rated at 0.020" tappet lift rather than 0.050" tappet lift. Bottom line: The 11-611-5 is too much cam for 9.5:1 SCR. Read this to get an idea of what I'm talking about.......
http://www.crankshaftcoalition.com/w..._compatibility
If it were my motor, I'd use 11-218-4 for some snappy street action. Comp suggests minimum 9.0:1 SCR. Your motor, at 9.5:1, would be perfect.
http://www.compcams.com/Company/CC/c...?csid=457&sb=0
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What does brad penn & joe Gibbs oil have that others don't? Like a zinc additive or something like that. I already run oil that has a zinc additive because i run a hydro flat tappet extreme 4x4 comp cams. Also I'm gonna be pushing the compression up to 11-11.5:1 on the next rebuild, sorry for not mentioning that!
Wow! Mechanical flat tappet, and then on top of that 11.5 to one compression?? Where do you plan to find fuel for your occasional use? I'm at 10.3 to one with aluminum heads, and I wish I'd gone closer to 9 to one so I didn't have to worry with finding gas stations with 91 or better octane gas, and then worrying how long it's been sitting in their tanks....
Couple gas stations in Boyne City have 93 octane so that's not a big deal.
Sorry for the hijack... I didn't know this RSpears.. makes me glad I targeted 9:1 even with the aluminum heads on my 347.. now back to our regular broadcast schedule! Sorry for the hijack...Quote:
Originally Posted by rspears
Yep, and worrying about what percentage of it is water. Smart money would build for 87/89 octane.Quote:
Originally Posted by rspears
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I couldn't agree with your more, Richard.Quote:
Originally Posted by techinspector1
Quote:
Originally Posted by techinspector1
So you would tells this to a drag racer that keeps getting beat as well? Don't worry you keep throwing your money out there and continue to lose! In my mud bog/run class I'm in, I'm right in the middle of the class. The people above me are running more power. I'd like to start getting some money back in return for going to events....Quote:
Originally Posted by rspears
Nope, my comments are more attuned to the street. For a competition vehicle you're in a different situation, but consider the problems with ethanol blends in your logic, too, like how much fuel to keep on hand between outings, how to store it (small volumes, less air), etc, etc. It's a different time than it was back in the day...Quote:
Originally Posted by Hoss Blazer
You're not being real with us. You didn't say anything at all about being in competition when you opened this thread. Here is your statement:Quote:
Originally Posted by Hoss Blazer
"How many of you guys run them out here? I'm looking at one for my next upgrade in my K5. I'm not realty worried about the life because I don't really drive it that much, more of a play toy."
We wil answer one way for a street cam (playtoy) and another way for a mud bog cam (competition).
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Well why can't you guys read my mind when I was first typing it! lol Definilty didn't put that in my first post did I, sorry about that. But ya it's mostly comp vehicle now....
It's all good, Hoss! I thought after the fact that you've had previous posts about the K5 being a bogger, but what with CRS and all....Quote:
Originally Posted by Hoss Blazer
CRS and all?Quote:
Originally Posted by rspears
CRS - Can't Remember S......tuff :confused::(;)
Just wait until you're my age. You leave one place in the house to go to another room to get something. Once in the other room, your mind goes blank and you have no idea what you went after. Now, you have to go back to the place where you started to get a mental re-up on what you needed and mutter it to yourself over and over as you make your way to the other room again. I can vividly remember stuff that happened 50 years ago, but current stuff.......not so much. Sorry to sidetrack this thread........or did I?
were you up in hale mi .there is nothing new about the EDM lifters with a hole in them been using them for 12 years now with good luck before thats was jonhson lifter /crower were they ground a flat in the side of lifter it is more then just oil it is that many of the bbc stock blocks cam center and lifter bore angle come in to play as spring LBS move up cam wear can to. on a poorly machined block .like i said many times on here i do not fool around much with many flat lifter cam s in bbc i think we talked about you using the EDM lifters last year ? yes i knew you ran mud ;)
So what would you choose then Pat?
i would use a solid roller as i built and been involved many engines for this use it.s no way close to what some think what you would use for valve train parts i built bbc that run in the 8000+. rpm range for year.s of use. one is the Time X engine parts need very good . i have used smaller solid roller cams and Psi springs that i could sell .on the springs you would need a min of 1.950to1.900 setup for the stuff i have but i am dealer for most all cams company and parts pm me on here or check out face book Mccarthy Performance or www.mccarthy performance.com if you want to talk about your build and what i can help you with
I'm into my second cam disaster in as many years. Big job cleaning up after a cam disintegrates. I'd use a roller. The oil we have now also destroys distributor gears. What ever you pick for a camshaft be sure to use the correct gear for it.
Al
when using a roller cam you must use the right distributor gear know the makeup of cam core gear. GM roller steel cam core needs a melonited distributor gear. after market all one pc steel roller core use a bronze gear .if a two part cam core with iron gear pressed on core or a S.A.D.I/Proferal core. stock iron gear .i never seen a gear fall apart from oil only . but added oil can be done by clocking #5 cam bearing oiling hole up to 12:00 clock . drilling a drain back 1/4 hole by boss of dist in back of block. use a Msd distributor has a gear oiler use the added o ring .work will need to be done to block . roll the dist boss in the block so O ring will not get cut . if the wrong gear was use on the distributor a cam core that was not made for the gear. things will not get along . cam end play is a big deal with a roller and checking the cam to dist contact pattern all plays in to how long a bronze gear will last . the make up of bronze alloy plays in to it as well as a HV oil pump