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Thu Jun 23, 2011 11:01 pm

2276cc with fk7 or fk8.............or...........engle 120 with 1.25 rockers........what would be the differences between these three cams....hp, torque...rpm range, driveability? carbs will be dual HPMX 44's

Thu Jun 23, 2011 11:14 pm

What heads & compression ratio?

Thu Jun 23, 2011 11:32 pm

FK cams have slower ramps to accommodate the high ratio rockers - the 120 has a bit faster ramp but can be used with 1.25 rockers. I'd stick with either of those FK cams with high ratio rockers. You might also take a look at the CB Performance 2242 cam - very similar to the FK-8 with even slower ramps than the FK-8 since duration is [email protected]" lift vs [email protected]" lift on the FK-8. Gentle is good for long valve train and seat life. Both have 'advertised' lift of 298.

I made that decision a few days ago - went with a similar cam offering by CB Performance - their 2242 cam and the Los Panchito heads (60cc) with dual springs & 1.25:1 rockers for my 2110 build. I also will be using the 44mm HPMX carbs with CB Perf linkage etc - set up by Art Thraen at ACE engineering. I had originally bought the Los Bandito heads (53cc) with single springs and an Engle 110 cam but those heads are too small (combustion chamber) to get a proper deck height without an astronomical compression ratio, or a deck height of nearly .090" - which would give me 8.8:1 compression - a bit too much compression and way too little squish. Fortunately my nephew is building a motor (with help and advice from the Unk) and hadn't bought heads for an 1835 build so he's buying those heads and cam.

Thu Jun 23, 2011 11:33 pm

That's another question mark. Most likely CB's Los Panchito heads with either 40 x35.5 or 42 x 37.5 valves..Not sure yet. I'm trying to build a motor that will pull hard. I'll drive it almost daily. I've got a 2009 Grand Cherokee that's my daily driver. I'll be driving this car to shows and on the weekends. And probably to work a couple of days a week. 8.5 to 8 to 1 compression. Shooting for 9:1

Thu Jun 23, 2011 11:36 pm

Ol nut---------what about the FK 42 cam? I don't want a motor that's all out race, but I want it to be juicy not tame. What's the RPM limit of the CB 2242 cam? I'm looking to peak out at around 6000 to 6500.

Fri Jun 24, 2011 12:23 am

More duration and heads are what moves the power band up the rpm range. I'm limiting my motor at 62-6500 and the 2242 will pull to that limit just fine.

The FK-8, FK-42 are similar cams - the FK-8 has more duration and lift - the FK-42 should idle more smoothly. I don't sit in traffic much so the rough idle of the 2242 won't bother me.

Fri Jun 24, 2011 12:30 am

I actually like the "rough" idle of big cam. Wouldn't bother me a bit

Fri Jun 24, 2011 6:57 am

I think a lot of the input you get here comes from the non stroker folks. 120 and FK7 are just not big enough I think for a 2276. I ran a 110 with 40IDFs, 043's that I ported mildly and also open the chambers to 60CC since I am also running 5.5 rods. What rods are you running? This could also determine your cam. I am running a 2017, 78.4x90.5. Running 44's and just went to a 130 Engle. Yes a 461 Lift / 308 duration cam and 267 @.050! I also opened my ports more and fly cut the heads to get around 9.8.1 C/R.

The 110 Cammed motor had a lot of torque but was done at about 5500 and no cammy idle that you are looking for. I really think what you are looking at would be about the same or maybe to 6000 with power. The .050 duration on those I think are just not going to be enough for that big engine and you wont be happy. I think the Los Panchitos heads, essentially what I have with all my port work are probable fine even though a 42x37 may be better. Now mine with the 130 Engle set up it is really great! I had people telling me it would be really hard to drive and not manageable in traffic Yada Yada. No it is very Linear and Smooth and seems where the 110 was over the 130 just rips past that. At about 3500 it comes on and just does not stop. Lost a little bottom right off throttle but really with the 110 it was neck snapping with a slight touch in first. Now it is not so harsh and easier to regulate and I think should I dare to say, more pleasant? The Stroke compensates for any loss of torque though. Yours with the larger stroke than mine would be perfect I think. You would have good bottom end pull and very nice power to probably to 7000 if you want to go there. I think going with an 120, FK7 or even the FK8 you might be selling yourself short with their mild .050 duration and you would be wanting more. I am running the 1.1.1 rockers as to keep it easy on the valve train. I also have a somewhat lumpy idle that you can tell definitely there is a cam in it too. What you want as well.

My buddy who has been building engines for years said with the stroker don't go small. I was talking 125 thinking that was radical and he said fock it go with a 130. Still did some homework. Shawn Proffit a guy I found surfing here is a big California drag racer and uses these cams all the time in his street cars with great reliability. He even said the 1.25's were not to hard on the valve train as well. I may go there but I have the Aircooled.net high dollar pushrods that I would have to cut. He also told me that the closer to 10.1 C/R the Better. I have driven it in 90+ and High humidity (Midwest) and it runs cool and no ping at all. Jim Ratto also said it would work well once you got your carbs tuned.

I too am using my car for the exact same purpose. Get a little radical but also able to drive on some long drives. Maybe to Eureka Springs MO from KC this year or next?

Go Big!

Fri Jun 24, 2011 7:26 am

I'd think about OLDVWNUTs suggestion and go with a lower, slower cam profile and make it up with the rocker arms. I've got a 130 with 1.25s in my 2332, but will be tearing it out this winter to put in a FK series or the CB 2242 cam to give my valve train a bit of breathing room. W series ramps are pretty harsh, and pulling the valve covers and watching the valve move as you spin the motor is kind of frightening when you thing about what is going on a 7000+ rpm. You want a good lift and duration, but you'll also want your engine to live for a while, especially since you indicated it gets driven a lot.

brad

Fri Jun 24, 2011 8:57 am

Old nut...you're right about FK vs similar W cams as far as raw measured ramp rates but the rate is relative to the rocker ratio it's designed for. So the FK ramp is still faster than the equivalent w series grind with 1.25's. Just trying to not have everyone who's NOT a cam X-spurt misstating information.

Fri Jun 24, 2011 9:16 am

RockCrusher wrote: Old nut...you're right about FK vs similar W cams as far as raw measured ramp rates but the rate is relative to the rocker ratio it's designed for. So the FK ramp is still faster than the equivalent w series grind with 1.25's. Just trying to not have everyone who's NOT a cam X-spurt misstating information.

At the valve with ratio rockers the FK cam ramp is faster vs a W120 with 1.1:1 at the valve - but not at the lifter. FWIW I've been reading (and understanding) cam profiles for over 40 years. Its good to see the cam manufacturers stating cam duration at .050" lift rather than using the generally less useful 'advertised' duration. They didn't give you that information 40 years ago. I don't think I mis-stated anything.

Fri Jun 24, 2011 9:22 am

I've used the 120/1.25's, as well as the FK8/1.4's and my preference is the FK8. It is one of the sweetest camshafts ever produced and if you search various forums, you'll find many others who agree.

The FK8 is very smooth on the street and yet, when you stomp on the accelerator, it's almost like a race cam in some respects, if you have the heads/CR to take advantage. Of course, this depends on what type of driving you'll be doing in the future. However, if you think there's a chance that you might try the odd 1/4-mile race, or some stop light racing, then go for the FK8 :wink:

Fri Jun 24, 2011 9:26 am

OLD VW NUT wrote: RockCrusher wrote: Old nut...you're right about FK vs similar W cams as far as raw measured ramp rates but the rate is relative to the rocker ratio it's designed for. So the FK ramp is still faster than the equivalent w series grind with 1.25's. Just trying to not have everyone who's NOT a cam X-spurt misstating information.

At the valve with ratio rockers the FK cam ramp is faster vs a W120 with 1.1:1 at the valve - but not at the lifter. That's exactly the point. The ramp is about what the VALVE does....not what the lifter does. The only interest in the lifter rate is in lifter bore wear.

Fri Jun 24, 2011 9:48 am

I have a similar build in mind. What I have so far: 2276, tims stage 1 plus heads(42x37), 5.4 rods, 1.25:1 rockers, w120, 45 drla's going into a fastback. Should I sell the 120 and go with an FK series?

Fri Jun 24, 2011 10:07 am

Depends what the purpose of the build is....daily driver, weekend winger, race race and nothing but race? FK are NOT what I would use in a daily driver except for the 41 and 42.

Fri Jun 24, 2011 10:47 am

weekend fun car, no raceing.

Fri Jun 24, 2011 1:32 pm

I have found that only YOU can perfectly cam your engine. , Some folks drive them in low RPM some in high RPM and that will dictate what you like. If a guy doesn't know much about cams he really can't pick the perfect cam, regardless of what someone suggests for him.

If you tend to put around, the w120 is for you, it will let you rev to 6K, but will perform good down low.

If you tend to gas on it the w130 is for you, it will rev to 7K, but wont do much below 3K

If you don't care about lifter bore wear, the VZ25 satisfies everyone I have ever used it on. It has good bottom end and will pull to 6500 with dual carbs and descent heads.

Of course you can run the 1.4 cams similar to the W cams. And you can have folks like SLR "custom" grind cams on different lobe centers and such for you.

Fri Jun 24, 2011 3:12 pm

Ive ran the fk 8 and now a cb 2250, the fk has less lift but 2 more degrees @.050,I cant realy tell any deferance between the cams. as far as rocker lift rates, have you ever ploted any rockers lift/degrees? it,s not a straight line or even a curved,more like a sigin wave, all over the place,and just about all rockers are deferent.I learned this from harvy crane one day we were discussing rocker development, he explaned it then said go plot a few and you will be scratching your head wondering wtf?? nature of the beast.I ploted a stock 1.1 and a new cb 1.4 2 days ago, at .020 & .050 the 1.4 gained about 4.5 degrees duration,at .100 valve lift the 1.4 gained about 7 degrees at .200 valve lift10 degrees. (10 each side would be about 20 deg total, no I did not plot the down side,I just wanted a quick comparason. it should be close to the same, it is a [email protected], 299 addvertized (I think thats what the addvertized was)
deferent type & raidus foot type rockers change a lot more than you may think, I now wish I had checked a set of my china 1.4's that have a deferent raidi foot.but already put stiff springs on the head. if you have the parts & time polt some lift /degree's of a few different rockers.and also change the pushrod length& rocker hight ,it also changes things fast.
I was also surprized the 1.1 rockers and the cb 1.4 rockers can use the same pushrod.none of my other 1.4's will even come close. perhaps that is why the added degrees are lower than I thought they would be at .020&.050" just a bit of food for thinking on,it may spark a few ideas in your heads.

Sat Jun 25, 2011 5:23 pm

Okay.....came up with the final parts list......2165cc motor(78x94)....CB's Los Panchito heads-42x 37.5 valves-mildly ported and polished intakes as well as match ported intake manifolds-59cc chambers....0.040 deck height for a CR of 9.2:1....Engle 120 camshaft with 1.25 rockers.......Bosch 019 Dizzy with electronic ignition....external oil filter...standard dog house cooling tin(all of it)...Kennedy stage 1 pressure plate.....chromoly push rods...HPMX dual 44's...custom breather box(all of those I've seen on the market just seem too small.........I'll be getting it all together soon and any input other than what I'll be using would be appreciated....and yes, I'll keep it all on this post