Hi all, I have a rebuild '72 455 with increased compression, estimated 9.5:1 but I will measure this exactly. Heatrisers pluged, the intake and exhaustports cleaned up. The engine has the '70 intake manifold and stock cast iron exhaustmanifolds. H.E.I. Ignition. Timing is 12# initial and 32# total. Stock Q-jet and 2.25" dual exhaust with X crossover. Stock convertor, stock gears. The engine is now running with (maybe some of you will throw up )o No: a Crane cam H218 Hydraulic cam, with .448 lift (intake) and .464 lift (exhaust) at zero lash. Duration @ .004 tappet lift 276 degrees (intake) 284 degrees (exhaust) Our parts suppliers here in the Netherlands mostly give us the choice of four brands: Edelbrock, Crane, Crower and Competition cams. But I dont like the idle quality of this cam and it doesn't make the torque from idle up. Now I have a Competition Cam 260H new in box (someone throw up??) Valve lift .454/.454 duration at 0.006 tappet lift: 260 degrees duration at 0.05: 212/212 degrees lobe seperation 110 I'm trying to get a smooth idle and increased torque in low rpm. I dont have to race with this car, but any performance would be nice... What are you guys think, am I muddling here or do I have the right cam here for my needs, or do you have any other suggestions? Most of you talk about Poston cams, TA and Kennebell, are they a lot better than Competition cams and what is the difference?. I have a double roller timing set from Edelbrock and I just put my cam straight up. Do I have to degree the cam, does it make any sense with this low profile cam? Thanks, Bram (The Netherlands):ball:
the cam you have in your moter should be a good cam for your set up, the comp cam that you want to install, might have a little better idle, but i dont think you will notice, from my experience a cam with even 205 intake duration will have a little roughness to the idle, both those cams should make good torque and h/p between 1500-5300 rpm. check your commpression, if you have less then 9 to 1 you could be losing alot of power there, and the bigger the cam the more commpression you need, you might be better off with a stock cam, specialy if you want a smooth idle. just my 2 cents p.s. you should always install the cam buy the cam card instructions. degreeing it will tell you that it is the what you payed for.
It took me a lot of years to think this through, but the stock Buick camshaft, prior to 1974, is the best cam for me. I concur with Kelly on this. Anytime you disign a cam to perform to a maximun in one range you give up performance or runnability in another range. Consider the Research and Development aspect of Camshafts. How many engineers worked to develop a cam that ended up in a 5000 lb vehicle that you could; A. not hear ilde B. smoke the tires from a dead stop C. Pull hard from 700 to 4800 rpm D. Keep an engine alive and running for 200,000 miles under circumstances where, after the first owner, the oil was probably changed with the Presidency. How many engineering hours go into the aftermarket pieces. With few exceptions, I would venture the formula is pretty well the same for every engine they design for. High lift, staggered profile and big overlap. Look at what the people who run extreme cams have to do to compensate for the loss of broad performance a stock cam offers. Gears, Valve train, Transmissions, carbs, Torque Converters, Headers, etc. All of this to gain, in most cases, less than a 20% improvement over the performance one could get from a well tuned, free breathing stocker. You can advance the stock 72 cam 4 degrees and have the same setup as the 1970 torque monster motors. I personally like the retard as it delivers a bit more in the lower range to compensate for reduction of compression. Face it, most people, including me, enjoy and buy these aftermarket cams because they sound cool. At my age and budget stock is the way for me.
I'm totaly in the dark when it comes to degeeing a cam, but with the info that I found on this site I can learn that. Can anyone of you guys tell me on what centerline the specs are based of the Crane cam? I can't found it on my camshaft specification card Do I get a little more torque at low rpm, when I advance the camtiming?? I've got a 3-way timingset from Edelbrock.. Thanks in advance, Bram
I mostly agree with what Tommy said, but there are other things that can be done. Keep the duration small enough to pull off idle, but a little increase to help pull to a higher RPM. Sounds like you guys would be better off spending the money on better heads. Keep you idle quality and get more power- win/win.
Advancing Cams.. I've just gone thru here and read your posts' and I'm pretty much in the same boat (age, pocket book & reliability) . I see where you're running a 2 1/4" dual w/ x-pipe . How do you like it ? In a Skylark with a stock 455/400 with "tuned" Qjet ,Cast Iron Intake/Exhaust . I've also "Street" Ported the heads clearing all the flashing/casting flaws and polishing the combustion chambers in hopes of running a bit more timing . Would a 2 1/2" system/x-pipe and the Cam Advanced 4 deg. be overkill , or would it give me a little more on the top end with the larger exhaust before it fell on it's face . Or should I run the cam straight up with a 2 1/4" ? I've never driven any car with a Buick 455, what will they pull like with a stock 455 / 400 ? Are they real torque monsters ? If I did advance my cam 4deg. What would the low/midrange torque be like , at about what RPM would it fall on it's face ? I've had the car almost 3 years and only driven it with a sloppy but strong 350 and was shocked the way it pulled . My 455 is almost together but will still be a while before I'll be behind the wheel . So I'm still a FNG when it comes to Buick . What little I've learned is due to you all , Thanks ! Steve
Hi Steve, The car I have, a '72 Riviera, is now in restoration. In during the resto I had made the X-crossover myself, but It's not installed yet. But the car has run in the past with a sort of H-crossover, installed by a muddler who doesn't know what he is doing. This bloke installed a bend pipe with a smaller diameter than the exhaustpipes..:blast: So I don't feel any difference in performance. I think a X-crossover or a good H-crossover should allways be installed in a dual exhaust system. I have no complaints at all about the stock 455 torque, but if you can add a little more torque it will just let you more smile.. After all that I have read/learned here, I conclude that if you advance your cam it will make some more bottom end torque but kills your top end a bit (Please, correct me if I'm wrong!) About the aftermarket heads: Here in the Netherlands these heads are unpayable! I will try it with my CraneCam in a 4 degree advanced setup and if I'm not satisfied I give it a shot with the CompetitionCam and if it all fails I put in a stock cam... But first I going to learn "how to degreeing a cam" maybe a local speedshop out here can help me a bit. The owner of that shop dragrace in a Chevy Lumina funnycar, so I think he know's what he is talking about.. Thank you all, Bram
Cams....... Hey Bram ,Thanks ! I would like to cam the 455 . But I'm a pretty reserved driver . I'm not trying to break a " Land Speed Record" I just like getting to the posted speed limit or there abouts in "Quick Time" with that GREAT Seat of the Pants Pull . I also doubt that it will ever see a 1/4 mile track . I'm just wanting a nice Cruiser with better than average pull . I'm sure with the Street Porting on the heads ,exhaust , tuned ignition , and a "tweaked" Qjet it will be sufficient :laugh: Hope all is well in your part of the world . Steve
