Just got a mercruiser 575hp
#11
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Joined: Apr 2010
Posts: 105
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From: Evansville, In
Sicksation,
The engine is the same basic platform as the Bulldog. The following is a spec sheet I posted on a previous thread. It is not verified, however, that the hard parts are to “mil-spec” as was the Bulldog.
541.9 CID
GM MK 4 tall deck (cast# 14044807)
Block clearance to accommodate 4.375” stroke
Siamese Bore, reinforced decks with blind head bolt holes.
Deck 10.2”
2 pc rear seal
Bore 4.44”
Stroke 4.375”
(With a factory recommended bore range 4.250’- 4.560” there is plenty of room for upgrades)
SCR 8.6:1
4340 Lunati crank
Piston is Wiseco (Merc part #)
Connecting rod is Manley +.400" / 6.535"
Dart Single Plane Intake Manifold
The major difference in the two is the camshaft. The Bulldog had a moderately mild HFT, while the 575 has a SFT, 256º/264º on a 108º+3º centerline, definitely not recommended for use with wet exhaust. As Ian stated, a roller would be your best choice here.
The 990 heads are the generic 320 rectangle port GM OEM offerings. In stock condition they will be your limiting factor.
The Dominator you purchased will work well if tuned correctly.
Bob
The engine is the same basic platform as the Bulldog. The following is a spec sheet I posted on a previous thread. It is not verified, however, that the hard parts are to “mil-spec” as was the Bulldog.
541.9 CID
GM MK 4 tall deck (cast# 14044807)
Block clearance to accommodate 4.375” stroke
Siamese Bore, reinforced decks with blind head bolt holes.
Deck 10.2”
2 pc rear seal
Bore 4.44”
Stroke 4.375”
(With a factory recommended bore range 4.250’- 4.560” there is plenty of room for upgrades)
SCR 8.6:1
4340 Lunati crank
Piston is Wiseco (Merc part #)
Connecting rod is Manley +.400" / 6.535"
Dart Single Plane Intake Manifold
The major difference in the two is the camshaft. The Bulldog had a moderately mild HFT, while the 575 has a SFT, 256º/264º on a 108º+3º centerline, definitely not recommended for use with wet exhaust. As Ian stated, a roller would be your best choice here.
The 990 heads are the generic 320 rectangle port GM OEM offerings. In stock condition they will be your limiting factor.
The Dominator you purchased will work well if tuned correctly.
Bob
#12
water inversion the cam has to much valve overlap ?? it would want to suck water into the combustion chambers with a wet exhaust
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#13
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Posts: 105
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From: Evansville, In



