Cam and valvetrain longevity....??? low duration high lift...
#71
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i am no cam expert but i have used crane 139651 cam in a handful of blown 540s with great results.it would be very interesting to see what a change to a 651 and nothing else except carb jetting would do.imo ,well never mind what i think.best to keep my thoughts to myself so nobody gets hurt feelings or thinks i am picking on them.
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#72
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Here's the deal...
All the speculation is wonderfull, But I think where Tim is at with this is that he has phucked with it long enough, he has thrown more than enough money at it, he is tired of stressing over it, he has tried to do it right multiple times and gotten repeatedly sucker punched. He wants an answer, he wants it to work right. He doesnt want to reinvent the wheel, he just wants to have his unbalanced tire stop shaking the car.
All the speculation is wonderfull, But I think where Tim is at with this is that he has phucked with it long enough, he has thrown more than enough money at it, he is tired of stressing over it, he has tried to do it right multiple times and gotten repeatedly sucker punched. He wants an answer, he wants it to work right. He doesnt want to reinvent the wheel, he just wants to have his unbalanced tire stop shaking the car.
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#73
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I know with my Bob M. 548 combo. (10.2 CR, afr 335 cnc heads, 454-R dom intake with 2100 cft TB. Holley efi. speculated 730-760 hp @6300 by Bob, I never dynoed) it was very touchy with prop pitch. I thought I needed to be somewhere around 25-26p prop with my 253 checkmate...ran it first year, thought it was a dog and was disappointed but was happy to be boating. 73-75 mph struggling to get 5500 rpm. End of that first year found out machinist pooched hone job and bores were quite shiny after 20 hours. Redo .030 over, add a lil extra compression, great ring package...new machinist. Put back in boat, turned the same prop the same rpm......dissapointed. Lackluster acceleration. Even tried a 24p with little improvement.
Now, get a wild hair on my azz to throw a seemingly tiny 23p prop on the boat. Guess what. Instantly screams to 6000 rpm in a heartbeat and climbs past 6300 in short order. Boat passes 80 mph within a mile. Prop was far from ideal (nicks and zero cupping hydromotive qiv) and was just a test, full gear and full fuel tank. Wound up running that prop rest of season with big ole grin on my face. Boat broke 80 mph which takes 700 minimum in that hull plus I keep a ton of gear and supplies in boat at all times, I never run "light." Could scream past friend's similar boat with 600sc merc.
Moral of the story, engine was very sensitive to small change in prop loading and I was my worst enemy. That engine wanted RPM and made its power up there, I wasn't letting it get there with slightly too big props.
Now, get a wild hair on my azz to throw a seemingly tiny 23p prop on the boat. Guess what. Instantly screams to 6000 rpm in a heartbeat and climbs past 6300 in short order. Boat passes 80 mph within a mile. Prop was far from ideal (nicks and zero cupping hydromotive qiv) and was just a test, full gear and full fuel tank. Wound up running that prop rest of season with big ole grin on my face. Boat broke 80 mph which takes 700 minimum in that hull plus I keep a ton of gear and supplies in boat at all times, I never run "light." Could scream past friend's similar boat with 600sc merc.
Moral of the story, engine was very sensitive to small change in prop loading and I was my worst enemy. That engine wanted RPM and made its power up there, I wasn't letting it get there with slightly too big props.
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#74
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i am no cam expert but i have used crane 139651 cam in a handful of blown 540s with great results.it would be very interesting to see what a change to a 651 and nothing else except carb jetting would do.imo ,well never mind what i think.best to keep my thoughts to myself so nobody gets hurt feelings or thinks i am picking on them.
One would think the 290 afr headed combos, would have made more torque down low, and the 325 combo, more peak power. What was interesting, the 290 combo made less torque down low, (nothing drastic), but carried better thru the midrange, and top end power.
I dont think tims 325 partially cnc ported are holding him back, as some have made waaaay more power than 630hp. I would have rather seen a dominator on tims build, but , i dont think the 1050 was holding it back. The professional products intake, idk, maybe could improve that a little. Engine had 36* of timing if i recall, and afrs of low 12s .
I think the only thing for tim to do, is spend some time finding out what the culprit is , keeping it from making the power he was promised. Not going to find it here imo.
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Which intake? 53030 ? No spacer? Whether that's the intake or not, I couldn't find the height listed anyway. What's the height?
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yes that would be interesting huh?? lol
Bring them back the dyno you used last time. Lets swap cams out, and see what happens. Then you can either further bash bobs cam , or offer him an apology lol.
We will have to video tape the entire process, so this time me and ryan wont be accused of sabatoging your build "to further our agenda"
We will have to video tape the entire process, so this time me and ryan wont be accused of sabatoging your build "to further our agenda"
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Like I said though, BOB was that guy.... at the time... so I thought.... until I had issues I thought he was a builder!!! he sure talks good....
All I know, and these are just two examples of guys I boat with all the time, is that when said guys went to Brad Smith (RIP) and Eddie Young, their mills surpassed their expectations and have been running trouble free for years. And neither guy knows how to turn a wrench. You do. So I'm not saying start over. But a builder with a proven track record on the poker run circuit, Shootouts, etc. should be able to take what you have and with hopefully minimal changes optimize the package for your goals. Again, let them do the thinking, spec'ing, tuning, etc.
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Actually, money was tight, lack of info was there to prove good or bad on cams, and yes boating season was coming, I prefer to use mine, ALOT and will not take a summer off to play with changes, I had a GREAT summer btw..
Seems everyone was suggesting he do that... He didn't want to spend the money at that time to do it... And the season was getting started. I'm sure he knows it needed to be done, and inevitably will be done but boating needed to come first, then worry about it later. Later is now. Tim quit blabbing on OSO and get your parts coming
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Basically yes... wanna make the best of what I have and not go broke, and stop worrying if valvetrains gonna fall apart, a 1mph gain would be cool too for the money spent...
Here's the deal...
All the speculation is wonderfull, But I think where Tim is at with this is that he has phucked with it long enough, he has thrown more than enough money at it, he is tired of stressing over it, he has tried to do it right multiple times and gotten repeatedly sucker punched. He wants an answer, he wants it to work right. He doesnt want to reinvent the wheel, he just wants to have his unbalanced tire stop shaking the car.
All the speculation is wonderfull, But I think where Tim is at with this is that he has phucked with it long enough, he has thrown more than enough money at it, he is tired of stressing over it, he has tried to do it right multiple times and gotten repeatedly sucker punched. He wants an answer, he wants it to work right. He doesnt want to reinvent the wheel, he just wants to have his unbalanced tire stop shaking the car.
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