A buffalo’s first bowtie

nuttyskier2002 wrote: By the way how many engines have you put together over the span of your lifetime? Not counting the ones your dad put together..... but you.

first was a '65 283 SBC, then I did '71 350 Olds, '76 455 olds, then there's the '77 350 and 80's 3.8L Buicks, and then don't forget about the HO 2.3L Quad4 too, want to know more? Want to know about all of the cam changes, intake changes, how about cylinder head replacements too. Or the time I replace my buddies motor in their boat after he throw a rod throw the block two days before his dad was going to Dale Hollow kinda saved there vaction for them that year. So you got any other bullsh*t to spout off about malibu boy

Thanks for the info on the summit house brand. I noticed they were a little cheaper, and I'll check on the valves and springs too. Those need to be replaced anyway, right?
I'm going to get the pcm service manual from marine engine, and I'll get some #'s up after I get the parts to the shop monday.
Are there better and worse types/brands of bearings?

BuffaloBFN wrote: This is the description from crane on that part #. I realize I can't use this exact cam, but this summary sounds like what I need. "Excellent low end torque and HP, good idle, daily usage, off road, towing, performance and fuel efficiency, 2600-3000 cruise RPM, marine applications: primarily used in 454 cu.in. near-stock engines for mild performance applications with free-flowing above water exhaust systems. 8.75 to 10.5 compression ratio advised." Does a barefoot qualify as free-flowing above water exhaust? They're under water at idle. And how about the compression ratio; our reference section has my motor at 8.12:1? Thanks again!

BFN, as for your compression with this cam, I'm betting that you will be boring your block and getting new pistons. This will give you the luxury of bumping the compression up to the recommendations of that cam. Just boring the block alone is going to raise it some. Also there are many other things you can do to increase it as well. Some of these are decking the block, milling the heads and thinner head gasket (within reason). How much you do will depend largely on your budget. I can also guide you to a good online static compression calculator.

Well a happy birthday to you Brian! And thank you so much you your input and time. I searched and searched for this sort of info.
I know the milling terms from my v-dub days, but I was advised not to 'get talked into raising the compression'. I clearly have more reading to do. I'm sure raising it a little to get into the cam specs would be ok, but you know I don't want to hot rod it, right?
Anyway, I think you're right about it needing to be bored, so maybe that'll be enough.

First things first though. What are the key things to ask the machinist about so I don't fall into the situation 79 described? I think I read here that the crank should be ground in the rotation it will turn in and that cylinder to piston clearance should be .020 for marine(larger than auto). How's my memory on these?

BuffaloBFN wrote: Well a happy birthday to you Brian! And thank you so much you your input and time. I searched and searched for this sort of info. I know the milling terms from my v-dub days, but I was advised not to 'get talked into raising the compression'. I clearly have more reading to do. I'm sure raising it a little to get into the cam specs would be ok, but you know I don't want to hot rod it, right? Anyway, I think you're right about it needing to be bored, so maybe that'll be enough. First things first though. What are the key things to ask the machinist about so I don't fall into the situation 79 described? I think I read here that the crank should be ground in the rotation it will turn in and that cylinder to piston clearance should be .020 for marine(larger than auto). How's my memory on these?

You are correct on the crank grinding. The crank or the grinding stone or both should spin opposite of what an automotive one does. It's been a few years since I've watched one being turned so I'm not sure about both, but that would make sense. As for the piston clearance, .020 is way too much. Standard automotive cast pistons are in the range of .0015 to .003 (measured at the skirt). Forged pistons fit a little more lose (like .004 to .006). The pistons I just bought for the 350 Chevy I'm building fit at .005 as recommended by the manufacturer (TRW Forged). The reason for piston fitting a little more lose on marine engines is this: with lake water cooling the engine and ~140 thermostat, the block will run quite a bit cooler than an automotive block. But the piston will still heat up almost as much as the auto one so it will expand.... but the bore will not. Therefore the extra clearance is taken up in thermal expansion of the piston. Always follow what the manufacturer's (of the pistons) recommendations for piston clearance for the intended use. If you buy pistons and this information is not supplied for marine use....contact them. Then when you have the clearances recommended, take them with the block and pistons to your machinist. Tell him you want the block bored and finish honed to those dimensions with torque plates installed on your block. This is nothing new and a good quality machine shop will do this as standard practice. Pick one that will.

79nautique wrote: why did I choose, Jasper? well the one machine shop locally doesn't have the means to balance the rotating assemlby and the other one is an idiot and takes for ever. My buddy found that out the hard way and now he's also learning the guy's not to bright either but maybe his new motor will stop burning oil some day. Oh and there is the deal with the block being cracked so it really is un-useable, but Jasper would take as a core at full value and then a 18 month warrenty too. Pretty simple logic actually and they sponsor a friends cars so a few extra tweaks where made that normally would have been done how car you loose.

Sounds like you made a wise decision. Don't you miss your boat? Looking for a replacement or do you already have one? Future project?

BFN, keep in mind that the numbers I posted above are only ballpark figures. You need to get the specs from the piston manufacturer.

I ordered my parts from Summit. Went with TRW forged pistons, Clevite 77 "P" series bearings, Speedpro moly rings. Arizona Speed and Marine is doing my block work. TRW recommends .005 for my clearance which I first thought was a little lose. But my machinist said he was going with that spec due to it being raw water cooled. He will be milling my block some (approx. .020) to reduce the "quench" dimension to .040-.045 with a .039 thick head gasket. My cam is a Comp Cams roller with 212/218 and .488/.495 lift and 112 lobe separation. My static compression based on a 64cc combustion chamber will be 8.6:1 as my pistons have a 21cc D shaped dish. My heads are Vortec type but not made by Chevy. Instead they came from Racing Head Service located in Memphis Tenn. They are equipped with stainless valves, Comp Cams springs (recommended by them for cam), screw in studs, teflon seals. My intake is a Weiand and is very similar to the Performer. I know my compression may be a tad on the low side (I'd like it to be about 9.2:1) but the engine guys at ASM say I should get about 330 HP out of this. Thoughts?

I probably should have went that route to begin with but at first I was only going to do a cam, intake and head upgrade because my motor is still good (<300 hrs). But when I found out that vortec heasds work best with a D-shape dish type piston, i decided to go ahead and buy a core engine and start fresh. I've purchased my parts already so I'm going to stay the course. A stroker would be a very nice upgrade though. I appreciate the thought.

The engine manual in the reference section here has 2 compression specs for my motor unless I'm reading something wrong...
page 14 - 8.12:1
page 15 - 8.8:1

Thanks for your input 79...it's worse than it looks in the pic. Case hardening worn through? This'll sound stupid, but do you mean where the 'silver' has worn off of the lobes? On 3 of the lobes, the wear looks close to even but is worn through the silver; on the rest, the wear is on the rear edge of the lobe in relation to the motor and worn through. Seems to me that the wear should be centered on the lobes, but I'm in school here.

now you know why we stress a roller, it eliminates those wear patterns you are seeing, the metal didnt disappear its somewhere in that motor,that is pretty much normal wear, normal in the aspect of not as many oil changes, high hours, dirty oil, heavy spring pressure and so on. sometimes the lifter holes are not perfectly perpendicular to the cam. take a good look at the wear on the lifters that rode on those lobes, I know your putting new lifters in. case hardening is like a chocalate covered cherry the surface is hard and the center is soft, i dont know if they harden the cams through or case harden them.
Greg, are you doing all the assembly work or is the machine shop?

nuttyskier2002 wrote: BFN, refresh my memory a little....Is the the motor that has ~2500 hrs?

I'd say that is close...could be over or under, but I'd guess that's a fair estimate. This boat has a long history starting with a lot of footing and more recently, a wakeboard school and a local outlaw team. One of those outlaws is a pro in orlando now(last I heard).
FWIW the hour meter has 1700 on it now and was disconnected...intentionally I think.

One thing you may want to do during the surgery is to store the crank vertically on the floor if you dont have it that way already. Now this is only my opinion... I dont use high volume oil pumps i never had any good reason to say this is why i use a high volume pump, i have reasons not to but i am open on this subject, my reasons not too: they rob horsepower, the extra pressure loads the bearings, the higher volume of oil foams loosing its ability to lubricate

eric lavine wrote: One thing you may want to do during the surgery is to store the crank vertically on the floor

I didn't have it this way, but I do now. This is common practice? I know what happens to wood when it's not stored right, but what's the deal on this?

If you see anything else I shouldn't do, please don't hesitate to tell me! LOL
I should've titled this thread 'greenhorn and his big block?!!?   

Nutty, did you buy your cam set yet? i have a complete set up out of a 5.7 with 11 hours on it, it is damn close to the speced cam you are looking at, it is a roller and is a factory set-up from Merc. it is in brand new condition also with it is the double roller set-up and harmonic balance,
the boat wasnt winterized and i stripped the old block which was new and installed a new engine for the guy. I will give the cam set away if someone will use it in thier motor.
i saved it for the next stroker rebuild and wouldnt hesitate using it, Merc specs thier cams for marine use and are backed by R and D. its not a croassover it was designed for marine use