I am putting together a rb motor ,4.250 crank,7.100 rods,0 deck,eddy heads (with light bowl work,gasket match and race valve job),10.5 to 1 comp. and I was thinking of running the comp.xe295hl cam but I was thinking about a hyd roller as well.I am looking for a nasty idle but still be streetable,(mostly a street car)And low maintance(basicly the most power I can get for a street driven car).I live in a rural area so I have to drive the highway to get anywhere,but anyway here is the cam specs. I was thinking of
Roller comp.xr292hr
dur. .050 242 248
lift .549 .544
110 lobe
valve timing at .006 lift
int. open 15 close 47
ex. open 58 close 10
xe295hl hyd
dur. .050 251 257
lift 564 564
110 lobe
valve timing at .006 lift
int. open 42 close 74
ex. open 88 close 40
I dont get the valve timing thing,but which one do you guys think would be better for a nasty idle and best power and live a long time on the street or is there a better choice than either one of these?Basicly I was wondering if the hyd. roller would make more hp. and tq.than a flat tappet hyd. cam and last on the street.Thanks guys.


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P.S.The car is a 69 superbee,auto trans ,thinking of a tight 3,500 stall convertor,3.55 gears or maybe 3.90s with a gearvendor,tti 1.7/8 headers eddy rpm intake.Thanks again

A HR will that has the same @ .050 numbers to a HF/T will typically have 12-15 degrees more @ .200 and will "dwell" the cam at peak (unlike any non-nascar full race FT) for several degrees.

Generally the HR will have nearly the same idle charachteristics for the same @ .050 duration but will roll-on the power and respond more like a solid FT to around 6500. A flat tappet spends so little time at peak so I really look at the duration .050 down from peak to make a cam/headflow decision/comparison.

Look at Bullet cams...they have a lot more HR cams to choose from and they're pretty aggressive compared to the comps.

FWIW I ran a Straightline 252/258 @.050 HR in a 4.25 stroke 508 several years back, it had very broad wall-to-wall power and torque but had a (suprisingly) relatively mild idle that I would compare to maybe a Comp 290s F/T in a 10.5:1 440. The Comp you call out would sound pretty tame at idle...I'm sure it will run very strong... but it MIGHT not live up to your "auditory" expectations.

PS , you'll need to either go to 2" header or convert your 1 7/8 header to a full 3 1/2" header collector....the 3" collector is going to really CRUSH YOUR TORQUE and decimate your HP curve by artificially limiting your peak torque to too low of an RPM, a 3" collector is small for a 440 motor let alone a 511.

Thanks streetwize,I will check out bullet cams.I just ckecked out hughes hyd.roller cams and they have a lot to choose from,but most of thiers were at 108 lobe and comps.are mostly 110 lobe.How would that affect idle and hp ,tq.Are hughes cams any good?
Thanks for the info.I was just worried about fitting them in a 69 b body.Will the tti in 2 inch clear everthing?

Pretty certain that Bullet grinds the cams for Hughes..

I run a 'bit bigger' bullet HR in my 12:1 517 with 108 centers and she's an awesome piece and very responsive:

http://www.youtube.com/user/wizerulz#p/a/u/0/jd8GeXYYkKU

Don't forget you headflow compression, gearing and how you drive should be the biggest factors in your cam selection

Great video,sweet car

would be better for a nasty idle

Swap the 5 & 7 plug wires

I would skip the hyd. roller and go with a mild solid roller. With today's lobe technology, you can have a fairly maintenance free valvetrain and run modest spring pressures.
FWIW, the hyd. roller will most likely sound like a solid roller anyway. Seems like knowone makes a perfect performance hyd. roller lifter thats quiet.
Allan G.

Thanks turbobitt,I will look at some of the solid roller specs as well.I am just looking for good power and tq,that will last a long time on the street with a choppy idle.Smooth idle cars at the criuzes and car shows get no looks.

If you tighten the LSA from 110 to 108 on either one of those cams in your first post the idle will get more agressive and you will have a broader torque/power curve and the power will hit sooner. You could even go down to 106 on a cam that small. But when the cams get really huge, like over 265-270 @.050 then the LSA has to get bigger/wider so the overlap does not get out of hand.

I would think a Bullet HR cam with something more like 260 duration and a 108 LSA would be good for what you want. I would call them and discuss it. As an added benifit, you will have a better power curve and more of it!

With the issues we have seen with the hyd roller lifters not pumping up and loosing their prime,I would think carefully before choosing that route.

Thanks for all the info.guys,now I need to start calling around.Will I have to do any oil passage mods. to the block to run either the hyd.roller or the solid roller or am I good to go