TheViper

i'm going to be building a 350 and was wondering what the differences beetween the crane 278-2, with a 114LSA or having a comp XE268 ground on a 112LSA. does the comp have a more aggressive ramp rate? what would make more power and would either one of them give a better idle or better fuel milage?

F-BIRD'88

To understand and compare these two cams you have to first understand that CompCams measures their cams at .006" lift and Crane measures theirs at .004". Therefore the Crane cam will appear to have have a longer seat duration, than the Comp even while haveing a .050" duration of 2 deg less..

If you measured the Crane cam using Comp cams spec of .006"
you'd find that the seat duration would be about 264 to 269.
(I have not actually done the measurement). You'll find that the intensity of the two cams are very close.
If you wanted to you could phone Crane Cams tech line and they could probabily tell you the exact spec @.006" so you could accurately compare it to a simular Comp cam.

You have to understand that the specs alone don't tell you exactly how the cam will react in a motor as compared to another
seeming faster or slower action cam.
Often, it is just the opposite of what you'd expect.

That being said. the best way to compare these two cams is by the .050" durations and lobe separation angles and the installed intake centerline. (advance)

The Crane cam with its wider lobe separation will have a smoother idle, wider power band, more vacuum idle and favour a closed exhaust system. The extra exhaust duration also favours a stock exhaust ports poor breathing.
The crane cam *should* get slightly better mileage.

This crane cam with its wider lobe separation and longer exhaust durtation is very NOS friendly especially if advanced in the motor a few more degrees.


The Comp cam on the other hand has more overlap and more intake duration will have a little rougher idle , less manifold vacuum,, the power will come on later than the Crane but will make more peak torque (especialy through open exhaust).
It *should* make a little more peak hp too.
But may not if through typical closed exhaust.

Keep in mind these are simular cams. They will be more alike than different.

Recently there were a few advertisments in popular auto mags claiming that Crane's particular cam was better than Comp's.
(in a near stock motor) {it was} Comps reply was that they would have used a different Comp Cam to compare
to the Crane. (actually a much bigger Cam) they also claimed 100 some hp more. I emailed Comps tech line a for clarification and proof. they admitied that they tested their cam in the near stock motor through closed exhaust and the Crane cam did in fact make more power. Then the retested in a different motor with aftermarket heads and open headers etc etc and their larger cam with tighter lobe separation. (extreme energy). Well as expected it did infact out power the Crane in this near race motor., in dyno trim. (they compared their different larger cam to the same smaller Crane cam. Hardly apples to apples.

I questioned them on this and invited them to use my motor and car for a true fair apples to apples test of their best suited hyd cam against Crane's best suited hyd cam. Well they didn't accept the challenge. They replyed by admitting that the Crane is better suited to a near stock motor and closed exhaust.
Their cam series is better suited to a higher level of engine build and a open or free-er breathing exhaust system.
And they do not recommend using stock valve springs on any of their extreme energy cams.
(Crane also recommends an upgraded valvetrain for best results.)

All this aside, Crane and Comp hyd cams are very simular in lobe intensity and power potential.
They both have to work under the same conditions in a motor and are limited to the same physics.
Both are considered hi intensity, modern asymetrical high lift lobe designs.
Use the .050" specs to compare and select the right cam for your car and leave the lobe intensity
to the engineers. Use the manufacturers recomendations for selecting valve train parts.

I use both their products.

When a Comp cam suites your needs use it. When a Crane cam suites your application use it. They both work well.

I've used the Crane H-278-2 (HMV-278-2) . its a good one.
its easy to live with and makes good power.
I have not used the comp XE268-H10.
It will tend to want a little higher stall and some better exhaust.
Both like a higher rear gear ratio.

Why don't you phone Crane Cams tech line and ask for a spec on the Crane H278-2 at .006" instead of .004" and post your findings?

TheViper

thx, i think i'l go with the crane 278-2. i hope i can get started on the engine soon before i change my mind again.