Reply With QuoteDamn!.. I want a whipple... Hows it feel?..I may never know. :frown:
Totally different boat. I love it!:rollside:
60 Whippled hours and going strong! (Quick, where's some wood to knock!)
Damn!.. I want a whipple... Hows it feel?..I may never know. :frown:
Damn!.. I want a whipple... Hows it feel?..I may never know. :frown:
Totally different boat. I love it!:rollside:
:idea: I just think it's funny that some think the motor is "junk". It's only a big-block Chevy. Just like all the ones in the past, but with some different heads and probably the weakest cast pistons they have ever put in a BBC. It can take mods just like any other BBC!
Come on B-30, I didnt say it was junkI just think from what I've read and heard that it's better off left alone because of things like cast pistons thats all. :idea:
92562, more power to ya and I hope it lasts forever
:idea:
Come on B-30, I didnt say it was junk
92562, more power to ya and I hope it lasts forever
Ya know, after I sent that post, I though about the way it sounded. I know you don't think they are junk, and I should have clarified that. SOME here think they are, but I believe we can find a junk part on ANY stock motor. Until one builds one from the ground-up with all the right components (which can still break upon occasion), there will always be a weak link or two from the factory. It just bugs me when people say to "give up" on them. Big blocks have been taking mods in stock trim for decades. These are no different. That's what I meant.
Beer-30, correct me if I'm wrong, but from what I understand, the reason the 496HO doesn't work very well when supercharged, is because the ring lands are so close to the crown of the piston, that with the cast pistons are prone to failure.
Because of the piston design, the 496 is a great engine when stock, but doesn't set up well with the extra pressures.
Some have had success, but for the most part, it's best to leave them normally aspirated.
Damn!.. I want a whipple... Hows it feel?..I may never know. :frown:
See what I mean, hell, just throw on a supercharger and be done with it, Run a bunch of boost and go fast, sorry it dont work that way and on top of that it's pretty expensive, just PM 92562 about it. It's all just info so you can make an educated decision, thats all it is. Good luck to you!
Beer-30, correct me if I'm wrong, but from what I understand, the reason the 496HO doesn't work very well when supercharged, is because the ring lands are so close to the crown of the piston, that with the cast pistons are prone to failure.
Because of the piston design, the 496 is a great engine when stock, but doesn't set up well with the extra pressures.
Some have had success, but for the most part, it's best to leave them normally aspirated.
That's what it appears. I believe the "main" and frequent failures are pistons right at the upper ring land, and rocker failure. I have no doubt that running a whipple at over 3.5lbs is borrowed time, just due to weak pistons. I sincerely hope some people are running 5lbs and run 300+ hours, just to do it and prove it can be done. More power to you.
My outlook is; EVERY motor with standard stamped steel rockers that ride on metal to metal pivot points could benefit from roller rockers. The reduced friction frees up a little HP that would normally be used to drive the rockers against the ball. Additionally, using a good quality rocker will add tremendous reliability. The motor will run smoother and the wear at the tip of the valve stem will stop.
So, this is just one of many mods that anyone can do (after all the proper components are purchased) that benefits any other BBC as well. Anyone saying to just leave an 8.1 alone because it is junk and not worth wasting money on; simply either doesn't want to touch the motor or has something bigger and faster already in mind. Those of us that plan to keep our 496 around for the life of the boat can do many "little" things to prolong their life and add dependability and some HP.
I had originally tossed around the idea of adding 1.8 rollers to bump the lift to .540. However, since then, I have noticed most all of the aftermarket cams for STOCK heads don't go over .513 lift. This is due to flow data that shows the stock head just doesn't due much after .500. So, no since wasting money on more lift (1.8 vs. 1.7), and also putting the valvesprings in jeapordy.
Beer 30, your last paragraph is why I considered the Raylar top end package but after reading the stories, both good and bad (acually the bad ones) I became very hesitant to spend that kind of money. It sounds like it is where the engine needs improvement and the results sound good ie; Shadows boat, but then for the good results there are bad ones also :idea: I think if I do something for more speed I would look for a blue motor or custom and just sell the 496, at least they are designed for racing use and you don't have to reinvent the wheel so to speak. I'm sort of in favor of not tinkering with things that work well as is and the 496 does that. Also it would be a waste of money in my case because I would be unable to use the xtra HP if Momma was in the boat, I have dagger marks on my back as it is if I go over 50mph :notam: Thats not to say you shouldnt tinker because the need for speed is very contagious and satisfying so "GO FOR IT" Now go to work and quit screwing around on HB!! J/K NSF (Bobby)
Beer 30, your last paragraph is why I considered the Raylar top end package but after reading the stories, both good and bad (acually the bad ones) I became very hesitant to spend that kind of money. It sounds like it is where the engine needs improvement and the results sound good ie; Shadows boat, but then for the good results there are bad ones also :idea: I think if I do something for more speed I would look for a blue motor or custom and just sell the 496, at least they are designed for racing use and you don't have to reinvent the wheel so to speak. I'm sort of in favor of not tinkering with things that work well as is and the 496 does that. Also it would be a waste of money in my case because I would be unable to use the xtra HP if Momma was in the boat, I have dagger marks on my back as it is if I go over 50mph :notam: Thats not to say you shouldnt tinker because the need for speed is very contagious and satisfying so "GO FOR IT" Now go to work and quit screwing around on HB!! J/K NSF (Bobby)
I finally got the wife to go WFO. We were running from Channel to Springs with our friend in the 25' Tremor, and no one else was out there. She kept pushing more and more forward. Finally, I look and noticed the stick was pinned. She trimmed it right where it needed to be and we were neck in neck. It just bothers me to picture those stock rockers flying around in there at 5000, when a smooth set of rollers would take some load off. Eventually I will do it. I am waiting to see if CP comes out with their 8.1 valve covers that they are rumored to be working on. If not, I will get Crane, Lunati, or Comp 1.7s and run vc spacers from AZ Speed and Marine. I just want it smooth and reduce some of the internal stress. None of this will put any more pressure on the pistons, so it's all good. Plus any of these parts could be used on another motor if this one lets go, so I am not stuck with useless parts.
With 1.5 gears and 5000rpm your theoretical speed would be 85mph so I see no problems here.
Hey Matt just to check the accuracy, I have a 496 MAG HO with Merc 28P prop, I am running a Teague Platinum XR with .........what should my top speed be?
I can comfortably hit 4800RPM, however I have a 29' boat so I don't trimm it out too far or I slip too much!
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