Overcamming Questions

[bugguy1967]

looking at dyno figures and engines specs, it looks like we tend to overcam our upper powerband engines. I see cams that are meant to provide useable powerbands to 8000 RPM peaking at 6500-7000 RPM. That tells me that headflow or intake flow was not adequate for the profiles they're matched to.

CB's 2300 cam was paired to their shootout 2332, producing a little over 220HP at 6500 RPM. Based on the Advertised head flow specs of their Ultra Wedges, it appears that the heads were at or nearing their max flow capability. Since the #2300 had another 1500 RPM, that would lead me to believe the 2300 needs much larger heads to be used to its' full capacity.

I've actually seen a lot of dyno figures where engines with FK87s and 89s peak at 7000 max. Is this a known practice to squeeze out all the flow from heads and leave RPM on the table, or are a lot of people choosing the wrong cams?

I've personally seen a sub 2200cc street engine with correctly matched 44 intake Wedgeport heads and FK8 make 210 flywheel horsepower. Then, elsewhere I see 2332s with bigger cams with the same valve size struggle at 200.

Correct me if I'm wrong, but the FK40 series seems to have a lot more potential than most give them credit for. The 47 and 48 seem to be only compatible with high-flowing 48+mm intake heads.
_________________
"A petrol engine can start readily, run smoothly and give every appearance of being in good order, without necessarily being in good tune." - Colin Campbell, "The Sportscar Engine"

[mark tucker]

you seem to have all the answers.

[Dougy Dee]

Was it all a bad dream???
I thought CB hurt their cam and swapped in something they got from Jack Sacchette or somone nearby.
An Engle I thought. Not a 110....

[bugguy1967]

Dougy, I think that was someone else in the competition. I seem to remember something about that.

Mark, if you'd like to add any helpful opinions, please do. I can't gain anything from your last comment.
_________________
"A petrol engine can start readily, run smoothly and give every appearance of being in good order, without necessarily being in good tune." - Colin Campbell, "The Sportscar Engine"

[Mad Manx]

[GTV]

It seems like you think the top of the useable powerband should be the HP peak?? It doesn't work that way. If your engine makes peak hp at 7k RPM and doesn't fall on its face until 8k, you can say that it pulls to 8k. This is so you can shift past the HP peak, keeping the engine in the fat part of the powerband.
_________________
EMPI Power Rules!

[mcmscott]

Just use a 120 and 1.25's with a 010............... typical samba shit, Wait! it must be for a 1641!
_________________
There are no stupid questions, only stupid people,

68 Ghia
67 T-1
65 Notch
02 Mexican beetle
74 Thing
15 Long travel rail
07 Nomad
05 f-250

[bugguy1967]

Ok. That's something I can use. I'm still a little confused though. Let's take the Engle W120, for example. If you look at dyno charts with this cam and matched components, it usually peaks at, or near 6000 RPM. I never see engines with 120s peaking at 4500. What's the difference?
_________________
"A petrol engine can start readily, run smoothly and give every appearance of being in good order, without necessarily being in good tune." - Colin Campbell, "The Sportscar Engine"

[Bajaman65]

I run a 2387 with a Pauter O3E8 10.5 cr that pulls hard up to around 7K on the dyno but I get the the best ET's when shifting at a about 6K. I have found that a dyno chart does not always tell you how powerful your engine really is, or how fast you car will be. There are many many variables. Good Luck and have Fun

[bugguy1967]

Of course. What are the .050" and lift specs on that 03E8, and where did your power peak?
_________________
"A petrol engine can start readily, run smoothly and give every appearance of being in good order, without necessarily being in good tune." - Colin Campbell, "The Sportscar Engine"

[VWCOOL]

[modok]

[bugguy1967]

When you say depending on what engine, do you mean depending on the engine's combination of parts?

I've seen dyno figures where the heads' ports were purposely kept on the small side for that cam, so that the peak power was all in by 5500. I've also seen charts where the power peaked beyond 6000 with more port volume. I would think if a 120's power was all in by 3000 RPM, there would be intake restrictions.
_________________
"A petrol engine can start readily, run smoothly and give every appearance of being in good order, without necessarily being in good tune." - Colin Campbell, "The Sportscar Engine"

[bugguy1967]

[modok]

Aren't all engines combinations of parts?
The engle 120 can be used in any engine with a lifter a little over an inch. It came from a yamaha motorcycle. Put it in a BIG tractor engine and sure you could have peak torque at 3k, and peak power at 5k, while a normal tractor would have a much milder cam, and run into a wall at 4500. it could be a vw, could be a chrysler, might be a type 4. use your imagination! one thing that would seem universal is higher rpm you need gentler ramps, and lower rpm engines would want faster. So there are some cams that would appear to never be the right choice, like a web 86; short duration and slow lift? huh?, or a fk-48, but they have their applications!
For every rule there are plenty of exceptions.

[bugguy1967]

That definitely does make sense, and I never thought about that aspect as far as ramps.
_________________
"A petrol engine can start readily, run smoothly and give every appearance of being in good order, without necessarily being in good tune." - Colin Campbell, "The Sportscar Engine"

[Bajaman65]

[mark tucker]

so if you use a 2300 with stock heads and another motor with comp E's and the same cam..but 2332cc .it will have the same power band gotcha....as long as you use the compatible lifters of coarse in your 1641 super gas motor. just think on how much money Ive spent on stroker shit when I just needed the majickle cam&lifter combo.

[bugguy1967]

[mark tucker]

POWER BAND AND USAGE ARE NOT WRITTEN IN STONE. THERE ARE WAY TOO MANY COMBOS AND THE WAY THERE PUT TOGETHER. descriptions are more like guide lines for the well educated and experienced... buit the numbers listed can be very vauge and not telll a lot about the cam.... and can be like wish list on talking points for the dude at the car/club show that hasent a clue that his combos is crap but has the sound he likes.
there are many cam manufactures that have the same/ very close cam on paper but they react different in the engine....way different. I read pretty good, my spelling is fine as is my understanding of cam/s engines/heads/cr ,etc. You might need a bit of real world experience...or not. as internet exsperts seem to be everywhere and know everything they read weather it is right or rong. dont be leave all you read,dont be disbelieving all you read. dont attribute one thing to the wrong part or combo.and dont decide the reason it's working so well is this 1 part or that one .you really need a reallife full understanding of what is going on and why. I will say Im kinda lost on exzactly what this thread is
and since you"taking the engle 120" and " matched componets"...WTF?? what are the matched componets?????????????