4.3 Marine upgrade

From the man himself....that is the marine ind....


11-19-2002, 08:07 PM #7
Dennis Moore



Posts: n/a What cam do you have now?

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http://www.offshoreonly.com/forums/...55-sbc-cam.html


SLP,
I don't think anyone can tell you what camshaft to step up to without knowing what camshaft you have now. From personal experience I wouldn't go with more than 218/224 intake/exhaust duration @ .050. Don't go with any thing less than 110 or more than 112 degrees of Lobe Separation Angle.
Any larger camshaft and you will have to run the engine above 5,500 rpm to make maximum power.
Your combo with the above cam specs should give you around 340 horsepower @ 5,200 rpm.
Call Comp Cams in Memphis for suggestions.
Sincerely
Dennis Moore
FAMILY AND PERFORMANCE BOATING MAGAZINE

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As to wave form cancelation aka as i have said vacum...And have eluded to eailer..reread my post's curtis...


Basic Operating RPM Range: 1,200-5,200
Intake Duration at 050 inch Lift: 218 ........
Exhaust Duration at 050 inch Lift: 224 .........
Duration at 050 inch Lift: 218 int./224 exh.
Advertised Intake Duration: 270
Advertised Exhaust Duration: 276
Advertised Duration: 270 int./276 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.495 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.503 in.
Valve Lift with Factory Rocker Arm Ratio: 0.495 int./0.503 exh. lift
Lobe Separation (degrees): 112.........


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If you are going to try to make comments on marine reversion...base them off fact's ...






Not yet, i still dont have a clear direction as of yet, iv'e been caught up in this reversion issue. It seems that Volvo has designed a nozzle for the lack of a better description at the end of the riser that shoots or sprays water down 4" exhaust that cools the tubing.


The down side is there is going to be some atomization of the water that could very well be sucked back into the header's due to valve overlap. But just how much overlap does that take 20-40-or 60 degrees seems to be the puzzling question.

Bondo as usual has provided a path as simple as extending the length of the exhaust aka though the transom exhasut...and after a little browseing i believe i have found a simple and cost effective way to do that. There was a term "Dumpster Diving" made and that led me to deisel truck's graveyard..You ever see those long chrome stacks..they sure would make some nice tubing to the transom...

Vovlo has also come up with simple H pipe connection for the 8.1 Don has confrimed as much but you cannot find any of the results on the net, Dont know if that is effective but it would negate back pressure and that's performance robbing.

I just need to answer some of my own concerns on that delima....It maybe as simple as capping the water at the end of the riser and injecting it down stream...Using a 6" ceramic coated extension pipe behind the riser and letting if all dump into the exhasut flare's.

Like you've been doing? LOL

I helped you w/your valve train questions where you are quite helpless (you're welcome, BTW), so when I ask Curtis an ill advised question, you quickly jump in to try to exercise your (primitive, at best) knowledge on the subject? That's funny, in a pitiful sort of way.

I wouldn't be surprised if the folks here get tired of your **** just like they have on the boating forums where you've worn out your welcome.

Good luck.

Opps colbat that redirection was not meant for you.I will be the first to say i directed the post to the wrong person and i apologize for that...i hope you can accept that.

As to my flame....well marine performance is like a black art...and things were said that were way off base. I will no longer post here...but serious misinformation need's to slapped down.

If your interest in marine tech is real......There are huge gains to be had...and as in any business discovering the dark secret's are alway's painful....unless you enjoy living in a mushroom factory.... And that comment was not meant for you Coblat.

PS...yes i am sharp angled....but i give far more than i take... aka as in this thread 116 lsa... ..........

Good luck, Gunner.

there is no "black art" about it, its physics plain and simple. If you want to use your will power to avoid reversion, I wish you the best of luck.

As for me, I'll take my puny pathetic 3 years of I/O experience and apply it on the tech/boating forums where its appreciated.

As i have said many times in this thread, your statements have lead me to conclusion's. Don't deem yourself as pathetic, i surely don't, but i will tell you this i have wrenched more that you guess...and went on from there....i have been in warranty vs engineering discussion's....Seen more BS spew en for the sake of reliability and yada yada yada

I shut off with the 116 lsa and the vacuum question's..It is vacuum curtis hold a dollar bill next to a exhaust with a stuck valve.....now that's overlap...Anyway's your adventure is beginning and i am no one to hold you back. So learn and carry on....Do you what deem to be right.

Thank goodness. I thought my 20+ years in the business (including engineering engines for Saab, GM, and Volvo) was wasted. I was ready to down a bottle of pills to end it all. But thanks to your condescending words, I'll carry on until the next anonymous internet insult.

Its no wonder the automotive companies are in the toilet... they listened to ME. I ruined the economy for all of you. I'm sorry.

Not at all Curtis your just 35 and full of life....you will recover...after all you have before....




Peace out..

Awww... you need to search harder. You missed the best ones:

















If you want to embarrass me with photos, you'll have to dig harder.