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jbenzeleski
08-20-2010, 08:50 AM
Will variable lifters help with water reversion?

mrfixxall
08-20-2010, 09:04 AM
i would have to say no! they take time to bleede down so during that time you may get reversion..

fysis
08-22-2010, 01:37 PM
i would have to say no! they take time to bleede down so during that time you may get reversion..
mrfixxall. What do you consider to be the upper limit that the exhaust could close in a carb 540 without reversing water in the combustion area with the Lightning headers. I know Cp performance said to keep below 10 deegres ATDC My camchaft is a Comp cam 234/240 a 0.50 617 lift the cam close the ex at 6 ATDC at 110int cent line.I even advanced the cam so the ex closes 3 ATDC. to bee on the safe side . But now i think i could use more cam since there are no signs of water and the engine is very "calm" 700rpm in gear. By the way Lightning says that the duration decreases by up to 10 degrees with bleed down lifters such as Rhodes.:sweden:

mrfixxall
08-22-2010, 02:23 PM
mrfixxall. What do you consider to be the upper limit that the exhaust could close in a carb 540 without reversing water in the combustion area with the Lightning headers. I know Cp performance said to keep below 10 deegres ATDC My camchaft is a Comp cam 234/240 a 0.50 617 lift the cam close the ex at 6 ATDC at 110int cent line.I even advanced the cam so the ex closes 3 ATDC. to bee on the safe side . But now i think i could use more cam since there are no signs of water and the engine is very "calm" 700rpm in gear. By the way Lightning says that the duration decreases by up to 10 degrees with bleed down lifters such as Rhodes.:sweden:


are you running a hyd roller??? 3* ATDC dont seem rite,post your cam grind.... for the speed your running you dont need any more cam,i dont like bleed down lifters in a boat,especially when in a marine application high lift cam's are hard enough on the valve train let alone a noisy one at that:)

i think you should start playing with shorty drives, that should put you in the 90 mph mark..

fysis
08-24-2010, 01:19 PM
are you running a hyd roller??? 3* ATDC dont seem rite,post your cam grind.... for the speed your running you dont need any more cam,i dont like bleed down lifters in a boat,especially when in a marine application high lift cam's are hard enough on the valve train let alone a noisy one at that:)

i think you should start playing with shorty drives, that should put you in the 90 mph mark..
mrfixxfall. YES running hyd roller. 234/240 a0.50 ex close 6 deg. after TDC .Since there where so much talk about reversion i advanced it 3 deg to bee on the safe side. When i selected the cam shaft i wanted about 10 to 15 deg more than the hp 500 .Locked at various cams around 230 -235 deg int.and .600+ lift. Which is the interesting part when selecting camchafts .but when it comes to marine wet headers the ex close point is of interest because of the reversion . Al of the cams in this category closed the ex. a few deg ATDC. I havent seen any water when i removed the headers from the heads so there seems to bee no reversion in my setup. Have you run in to that problem any time and if you did how wild cam where you running. Maybee i will step up a little in cam for next year to gain some power and since i have a pretty high cranking preasure at 205psi.As long as i can keep the reversion in check. You are so right about the Shorty thatīs the next thing for me. Think they are very hard to find used ones though. So maybee the solution is to buy a emty case with the shaft and then move my Bravo x gears over. I love your vette coupe I have had a few 63-67 myself. My first was a 66 conv 427 390hp everything ex Ac. Interesting about it was that it was sent from GM to Mr Kiekhafer himself for evaluation later Mr kiekhafer sent the car to Sweden to his friend and Mercury head dealer over here NK Kristensson.:sweden: