Will tall aluminum center-bolt valve covers fit?

NormRinker

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Will some tall height aluminum center bolt valve covers for Vortec 5.7L engine fit on there without interference with OEM MerCruiser exhaust manifolds and risers?

Just wondering because if I go roller rockers I may need some valve covers for clearance.. Not to mention some Bling is cool too! :)
 

Don S

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Re: Will tall aluminum center-bolt valve covers fit?

You will probably end up with clearance problems between the exhaust risers and the valve covers.
Be careful of the rockers and cams you use. You could easily end up sucking water back in to the engine.
 

NormRinker

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Re: Will tall aluminum center-bolt valve covers fit?

Hey Mr.Don,

I'm glad you came onto my thread and answered my question for me. Can I use a pair of short height aluminum covers instead that will still clear some roller rockers if I go with that? A little bit of bling in the engine bay would be great too!

What camshafts would you recommend that are mild and will conjure ok with the OEM MerCruiser exhaust manifolds and risers? One for a standard compression 355ci, another for standard compression 383ci? I'm still undecided between both engine sizes, and I have a thread on it. The thread is titled; "Mr.Don and Mr.Bondo (as well as the knowledgable others): Please help."

Do you know of any good roller rockers that I can use in Marine application without changing the geometry too much? Maybe something in the 1.5 - 1.6 ratio? I absolutely do not want to be sucking in some water after going through the repower situation I have right now. I only want some more power than the original 250hp.

Thank you very much Sir!

Norm
 

Don S

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Re: Will tall aluminum center-bolt valve covers fit?

Im not much into cranking the last of the HP out of any engine. I would rather have an economical, dependable engine that I know will bring me back from some desolate area out of cell phone, VHF, or any other type comunication, range.
 

NormRinker

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Re: Will tall aluminum center-bolt valve covers fit?

So, what do you think about the new near complete Vortec engines that Ebasicpower.com and MichiganMotorz.com offer for about $3300-$3700? They say the long blocks come from GM already marinized. These engines include the 4 barrel intake manifold with Holley carburetor on top.

Would one of these engine with this Holley combo qualify as "dependable" to you? I want to do the switch over from my original 2 barrel intake/carb set-up. Just a lot of options here I need to go through and make my decision from. I think only about 300-350HP would be great to have in my boat, but I don't want to give up too much on the area of dependablity. It is a great point especially how I can't hear or speak.

Thank you very much for the much needed assistance from you!
 

Don S

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Re: Will tall aluminum center-bolt valve covers fit?

For one thing, I have never had any dealings with Ebasic or mich.motorz so won't even comment.
I also wouldn't put a rebuilt engine from any company in my boat. They spend little time and little effort to make it right. That is why they sell long blocks for 1500 bucks. They are junk.
Most rebuilders have a warranty on paper, that is never backed up.
If you want a new engine with a warranty you can take to the bank, then Merc or Volvo will sell you one. But it won't be for 1500 bucks. But they have dealers for parts and service when (notice I didn't say if) you need it. Try that with some of the cheap rebuilders............. ain't gonna happen.
Merc also sells some rebuilts......... and the warranty is good on them also.
I also know what I do when I rebuild an engine, and would have no problems running one of my engines after a total rebuild. But it's also not going to happen for little money.
If you are going to sell things cheap, you have to cut corners if you want to make a profit.
I have probably gone completely off course on your question, but automotive and marine are so different in what happens to the engine, that it's like completely different engines and thought processes to make them work.
 

NormRinker

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Re: Will tall aluminum center-bolt valve covers fit?

I understand your point of view on this. I am still weighting on my options, and I am not in a rush. I will eventually make my mind up and proceed with it.

Thanks for your time.
 
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