Guest Posted December 31, 2000 Share Posted December 31, 2000 I looked up the stock cam specs for my 71 SS454 LS5. My resto packet stated that the LS5 is equiped with a high duration cam. Advertised duration on my the stock cam is 350/352, while duration at .05 lift is 214/216. In my quest for more power while using stock parts I was going to put a new crane blueprint cam in since I don't know whats in there now. I was wondering if Crane's variable duration lifters would help generate more low rpm cylinder pressure and more torque? I have also heard that advancing the cam 4 degrees moves the torque curve down lower. Any ideas. Link to comment Share on other sites More sharing options...
Guest Posted January 2, 2001 Share Posted January 2, 2001 OK, educate me, I'm new to variable duration lifters. I've never heard of them. Link to comment Share on other sites More sharing options...
Andreas Posted January 2, 2001 Share Posted January 2, 2001 Yes, the crane "fast-bleed lifters" will generate more torque by having lower lift at lower rpm and higher lift at higher rpm. I have them installed in my 383 and they are great! Another nice effect of these lifters is that they give you higher vacuum for your brakes compared to standard lifters. Also, putting the cam in 4 degrees advanced will help the engine low-rpm torque. But check if your cam is not already ground 4 degrees advanced, many of them are... ------------------ 71 Monte 383 "The Full Monty" 86 Monte LS ZZ4 "The Gray Mouse" http://go.to/Monte Member NMCOA, FGMCC "It ain't a car if it's not a Monte" Link to comment Share on other sites More sharing options...
Guest Posted January 2, 2001 Share Posted January 2, 2001 I have Crane variable durations in my 468. I cant say that I noticed a dramatic difference when I installed them,but I will also say that I installed the MSD ignition new cam,valve spings,a different intake and roller rockers at the same time. So my baseline was blown to hell.I will say that the rockers and the liters definetly added noise to the valve trane.Never had any problems with them. Link to comment Share on other sites More sharing options...
Guest Posted January 2, 2001 Share Posted January 2, 2001 Cool, never heard of these. I'll have to look into these when I get to my engine. How long these been around? Link to comment Share on other sites More sharing options...
Guest Posted January 2, 2001 Share Posted January 2, 2001 Well I think that Crane has only offered variable duration lifter for the last couple of years. But Rhodes has offered them for a long time.Although the Rhodes lifters make more noise they have been making them longer and you will find more old timers choose them because of this. Link to comment Share on other sites More sharing options...
Andreas Posted January 4, 2001 Share Posted January 4, 2001 Tommy, you are right! I was to buy Rhodes lifters because they have a better reputation, but Summit was out of stock, so I went with Crane... ------------------ 71 Monte 383 "The Full Monty" 86 Monte LS ZZ4 "The Gray Mouse" http://go.to/Monte Member NMCOA, FGMCC "It ain't a car if it's not a Monte" Link to comment Share on other sites More sharing options...
Guest Posted January 4, 2001 Share Posted January 4, 2001 Summit must have been out of those things for quite a while. Cause thats the same thing that happened to me. Rhodes wasnt in stock. Link to comment Share on other sites More sharing options...
Guest Posted January 13, 2001 Share Posted January 13, 2001 I have the rhodes lifters in my 454 , along with a large crane hydraulic , 300/310 -525/565 ,they definately give you loads better vacuum , and better low end , but the noise from those things ,I think it sounds like a diesel , I ran 'em for 1 season , I am going to yank them in favor of a comp/cams 270 magnum cam and lifters.....Tim ------------------ Link to comment Share on other sites More sharing options...
Guest Posted January 14, 2001 Share Posted January 14, 2001 i dont think there going to do much for your set up.there more for running a big cam with a lower comprion ratio to help restore vacuum and drive abilty at lower rpms.one thing you have to remember is chevy cam specs are weird and not taken like the after market.that cam is rather mild so i think you with have plenty of low end. chris Link to comment Share on other sites More sharing options...
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