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MESABALANCING 04-26-2006 04:43 PM

Re: Help! Burned piston
 
[QUOTE=fbh-velocity]

Originally Posted by scarab39
Laz, Thanks for all the info, I'm sure it will save me money and grief! I'll be plumbing a water pressure sensor in the block like you mentioned. What gauge do you use?

Ditto?

We're a Livorsi dealer and that's all we use it's a real good quality.

cstraub 04-26-2006 05:11 PM

Re: Help! Burned piston
 

Originally Posted by scarab39
actually, it's 4.53 bore. maybe that contributed to the failure?

You listed a 1037 Felpro as the head gasket. The gasket bore is 4.370". There is no way your bore is 4.530" because this gasket would be hanging inside the bore.

Your second picture in the first post shows signs of leakage between the cylinders on the gasket and the block. One issue.

I would take some rubbing alky and poor into the ports and check for leaking valves.

I would CC the heads and see what the chamber volume really is.

scarab39 04-26-2006 05:46 PM

Re: Help! Burned piston
 
oops, the gasket is 17048. I'm definitely buying new heads and intake, I'm just trying to figure out what to get. I'm leaning towards the brodix topend kit from summit.

PatriYacht 04-27-2006 07:44 AM

Re: Help! Burned piston
 
It's hard to know what to recommend without knowing more about your goals and how much money you want to spend. The heads are good heads and with a little port work can make a lot of hp. Now they have been damaged and should be sent to a good head guy to be repaired and have any damaged parts replaced. In our area Jim Valako is one of the best. The block is damaged and if it is a Gen 5 it is already at it's max bore size. If it's a Gen 6 you can go out to 4.560. The decks will have to be checked for flatness and possible cracks. Rods and crank to be inspected carefully.

If you are going to reuse the heads, you'll need dish pistons. A hyd. roller cam with a fair amount of duration. The small ports will make good torque and help it tolerate the longer duration. I would recommend the Crane 651. 244int @ .050, 256 ex. .630 lift, 114 lobe sep. I bet that will make 600hp at a rpm that you can use and idle at 800 rpm. Single plane intake, Dart, Merlin etc. Aftermarket dry exhaust. Good luck.

Big Block Billy 04-27-2006 10:15 AM

Re: Help! Burned piston
 
10-1 is pushing it on a boat . I would not run more than 9.4 -1
This is detonation. I recommend 119 CC heads. with the flat tops on a 540 should be in the 9.5 zone. If block and heads were decked you may need a special thicker Cometic gasket.
You're better off being on the safe side because you can't trust todays fuel, and one bad tank of gas and this happens. BBB

scarab39 04-27-2006 10:29 AM

Re: Help! Burned piston
 
The block is getting sleeved as we speak. I'm going to stick with the flat pistons and get 119cc heads and a single plane intake. I never much cared for sleeves but my motor guy says it will be fine for what I use it for.

Thanks for the help!

Wobble 04-27-2006 12:23 PM

Re: Help! Burned piston
 

Originally Posted by scarab39
The block is getting sleeved as we speak. I'm going to stick with the flat pistons and get 119cc heads and a single plane intake. I never much cared for sleeves but my motor guy says it will be fine for what I use it for.

Thanks for the help!

You might want to consider that 93 octane pump gas will not be available from 2007 on. 91 will be max.

PatriYacht 04-27-2006 01:07 PM

Re: Help! Burned piston
 
If you have the option, go with larger combustion chambers than 119cc. According to SRP's chart, you will still be at 9.9 to 1 comp.

JJONES 04-27-2006 02:29 PM

Re: Help! Burned piston
 
go with a mechancal fuel pump,this way the fuel pressure picks up as the engine speed increases,I had the same problem with my boat,many engines later we found the electric pump didnt have the voltage going to it to keep up,once mechanical pump was installed,no more failures

scarab39 04-27-2006 02:45 PM

Re: Help! Burned piston
 
I wish I could run a mechanical but the motors i have don't have a provision for a pump (mk VI). stupid chevy :)


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