I am looking at a boat with 500 Bulldogs in it. What do you all think of using these engine and installing 3.3 Whipples on them an what would you do to the engines as they are from Merc for the upgrades? They have about 250 hours on them and check out good as far as compression and leak down. I know the heads would be a weak link.. Thanks in advance.

I would install fresh head gaskets, a better cam/springs , and go have some fun. They will make good power with the Whipple's.

Best bet is to talk with Eddie young on that setup .

Thanks Joe. I was hoping that you or Mike would respond. If the boat deal goes through it will be a fun project.

I would be more worried about the drives with the whipples..

Chris

If memory serves me correctly, Bulldogs were 540 CI motors.

I believe they built two versions of them 500 & 540

Found this spec for the 540

The Merc Bulldog is an exceptional platform for upgrades. Many of these were contracted to the military, hence the overkill on the hard parts. Below are the specs on the engine.

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

Crane Camshaft Specification Card
Part Number: 13H000036
Grind Number: H-240/329-2-10 T1.2


The cam rates on a 110*LSA, 5* advance
Lift .329” Lobe .559” Valve
Lift .340” Lobe .578” Valve

Specs:

@.0042"
................Opens..........Closes............. C/L...........Duration
Intake.....43.0 BTDC.....77.0 ABDC......105*..........300 °
Exhaust...88.0 BBDC.....42.0 ATDC......115*..........310 °
85* overlap

@.050"
................Opens...........Closes...........C/L.........Duration
Intake.....15.0 BTDC.....45.0 ABDC.....105*.........240 °
Exhaust...60.0 BBDC.....10.0 ATDC.....115*.........250 °

Camshaft Is Ground with .0012" Lobe Taper

Believe you will have the tall deck block casting # if you have the 540 . I want to say those used fairly mild head gaskets from merc ,otherwise ready for big whipple power . The spacers for the whipple intakes have got cheap and plenty ,too