Just got a mercruiser 575hp
08-13-2010 | 08:29 PM
#2
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Joined: Jan 2009
Posts: 265
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From: TEXAS
1050 ProSystem Carb custom built.
CNC Victor Intake 454R for Big Block std. deck.
http://www.offshoreonly.com/forums/s...t-housing.html
Last edited by goebel1; 08-14-2010 at 07:44 AM.
08-14-2010 | 12:24 AM
#3
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Joined: Dec 2000
Posts: 6,283
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From: EASTON MA.
the gen 4 540 is a tall deck your post says you have a short deck intake, but he could use the carb and go with a single plane brodex intake by Gellners they take a oval one and match port it to sq port heads gives more tq and hp over sq port intake, thats what I am getting for my back up motor 509 going from 650hp to 700 with a carb/intake /cam change. in case the blower motor is to big
08-14-2010 | 07:43 AM
#5
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Posts: 265
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From: TEXAS
the gen 4 540 is a tall deck your post says you have a short deck intake, but he could use the carb and go with a single plane brodex intake by Gellners they take a oval one and match port it to sq port heads gives more tq and hp over sq port intake, thats what I am getting for my back up motor 509 going from 650hp to 700 with a carb/intake /cam change. in case the blower motor is to big
08-14-2010 | 12:29 PM
#8
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Joined: Apr 2010
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From: Evansville, In
the gen 4 540 is a tall deck your post says you have a short deck intake, but he could use the carb and go with a single plane brodex intake by Gellners they take a oval one and match port it to sq port heads gives more tq and hp over sq port intake, thats what I am getting for my back up motor 509 going from 650hp to 700 with a carb/intake /cam change. in case the blower motor is to big
Nice. Yea the motor has Ls6 heads on it.. 6272990 i believe is the casting number.. These pretty descent heads?
08-17-2010 | 04:54 PM
#10
MarineKinetics
Joined: Oct 2002
Posts: 942
Likes: 5
From: Rochester, NY
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
