will this engine combination work?

[advinnie]

Hi do you lot think that this engine combination will work? 
76mm crank
 5.5 rods
"B" pistons 
engle 100 cam 
 heads and value size not sure yet
  dual kadrons
4 into 1 header with a hideaway exhaust. 
Cheers. Im more interested in finding out if the 76mm crank with the 5.5 conrods and "B" pistons will produce a good deck height and if it will make the engine any wider?
plus will it pull the piston to close to the crank at BDC?

[AlteWagen]

With stock case deck you will have pretty huge deck height. Solution would be to deck the case and or cylinders.

Better yet go 78 with 5.5/Bs.

74mm cranks make builds a bit more complicated but 76s are just a PITA.
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[Quokka42]

From a stock deck height of 1.3mm, the 76mm will move the piston up 3.5mm, the rods by about another 1.5mm and the b pistons move it back down about 4.5mm leaving you pretty close. You will need to shim to allow for the difference plus any decking of the case and your engine will end up pretty close to stock width. B pistons should clear your crank OK, but of course you will still need to check everything in the case and clearance as necessary.
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There has only ever been one man who was perfect, and they nailed Him to a cross.

[advinnie]

Hi thanks for the replys. My deck height at the moment is 2mm / 0.079" and my cc in the heads are only 45cc that puts me with a compression ratio of 7.99:1 with 85.5 p&c but can anyone tell me the max compression ratio I can use? Cheers

[Quokka42]

A few factors come into play here - what fuel are you running, what size pistons do you plan to run, are you planning on sticking with the same cam? At present you are at about the limit for your cam, but if you are stroking the engine you probably need to look at changing your cam and cylinder heads anyway? What are your heads, they might be capable of being worked to suit the new engine?
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There has only ever been one man who was perfect, and they nailed Him to a cross.

[advinnie]

Hi im running unlead 95 Ron. The can at the moment has 278 degrees with .477 valve lift is this not enough?
The heads I have at the minute are stock with I believe 35mm inlet and 32mm exhaust. The pistons I was thinking of using were going to be "B" 85.5mm that way I dont have to spend money on enlarging the case and head's or using 90.5mm pistons if I must. Im not after a massive engine cause it will all be bolted to a gearbox from a 1200 beetle with a 4.375 drive so I need it yo rev high. Only after acceleration not top end speed butvmust also be drivable in town/ at low speeds.

[Quokka42]

Your heads are going to need some work. The kind of work described in HTHRVWs would work well for your engine, or you can buy new ones which already have larger ports and chambers. If left as they are your heads will tend to choke your engine and it will be hard to get your compression down to an acceptable level without excessive deck.
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There has only ever been one man who was perfect, and they nailed Him to a cross.