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Donziweasel
12-14-2008, 08:54 AM
Can anyone tell me about these engines? Look like the predecessors to the 500 and 525 blue motors. Good/bad?

MOP
12-14-2008, 09:15 AM
Don I am pretty sure they were stroked 454's, they have been around awhile and seem to be a good engine.

BigGrizzly
12-14-2008, 09:52 AM
The Real bulldog is the strongest built bbc series the con rod are tremendous and good to 1100 easily. All were carb version and rated at 470 HP, byt in reality with a little carb work it gets to well over 500HP and will kick the stuff out of any stock HP500 and most HP525. It is not a stroked 454 but a 502 stroked and boars except for the Volvo 540. Garry gets 700+ hp out of them modified on 87 and 89 octane pump gas. If I had the $$ it would be in my Criterion. The 540 comes in both tall and low blocks. The Bull dog is only in low block. I know where there are 3 take outs with 600 hours on them. Need to be freshened up. Never been rebuilt before. The guy is putting in 3 800+ 572s in it. something about being a Fountain eater.

gcarter
12-14-2008, 09:58 AM
I read an article that said they started with a high deck Bow Tie block.

BigGrizzly
12-14-2008, 10:17 AM
The tall block was very short lived and was flat tappets.

Donziweasel
12-14-2008, 10:21 AM
Randy, Pm sent.

fogducker III
12-14-2008, 10:22 AM
You will certainly "clean up" with one of those.......

http://www.mercuryfloormachines.com/machines/bulldog.htm



.......only two more sleeps..........:rolleyes:

Donziweasel
12-14-2008, 10:24 AM
You will certainly "clean up" with one of those.......

175 rpm's with 1 hp. Sweet! Sleep seems hard to come by lately......:wink:

BigGrizzly
12-14-2008, 10:35 AM
I forgot about the floor buffer. I used one in a comparison test against a pioneer eclipse with a propane Honda engine on it. The SOB turned me loose in a hurry. Both did until I learned to buff correctly. Can you say cork screw. DW you have mail.

harbormaster
12-14-2008, 08:05 PM
I sell brand new dart block based 540 shortblocks for 5800.00 (add 1000 for an aluminum block).

Donziweasel
12-14-2008, 08:11 PM
I sell brand new dart block based 540 shortblocks for 5800.00 (add 1000 for an aluminum block).

We need to talk.:)

VetteLT193
12-15-2008, 06:47 AM
Can anyone tell me about these engines? Look like the predecessors to the 500 and 525 blue motors. Good/bad?

Have you found one for sale? I don't think they sold many of them, especially compared to the regular HP 500.

harbormaster
12-15-2008, 09:34 AM
540 engines are kinda a generic now. There are alot of people building them.

BigGrizzly
12-15-2008, 10:35 AM
Scott is correct. the difference is the early 540 was a flat tappet and the dart isn't. the Dart is a good package Garry has built a ton of them. In fact his 700 hp regular fuel engine is on that base. That is a good price that Scott has, but you probably knot that all ready.

VetteLT193
12-15-2008, 02:13 PM
540 engines are kinda a generic now. There are alot of people building them.

I was only talking about the Bulldog specifically, assuming that the "bulldog" is specifically the merc. HP 500 bulldog. Is the term bulldog synonymous with the 540 block?

rmbuilder
12-15-2008, 08:23 PM
The Merc Bulldog is an exceptional platform for upgrades. Many of these were contracted to the military, hence the overkill on the hard parts. They were not the same bore and stroke as what we consider today as the conventional 540, with a 4.500” bore and 4.250” stroke. All Merc bulldog engines were based upon a tall deck block. 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

Bob

BigGrizzly
12-16-2008, 09:20 AM
Couple of things. There were a ton of Merc bull dogs made in the HP500 configuration. A lot of sport boat manufacturers used them. They were quite common in the industry as a whole. There was an issue on the valve springs because the maker had a flaw from the vendor on tempering. It was the same springs that gave the HP 500 the spring life issue. Garry actually pulled a new one down years ago and found different spring rates across the board. As for the listed specs. that were posted, they have changed as to cam and pistons. The carbs were set yp really bad. Years ago I saw two in the same boat that were jetted differently. one engine would pull 800+ rpms more then the other. At first I though it was the props not so. Nuf said on that issue.

frclarke
12-17-2008, 03:22 PM
I bought a "Bulldog" 540 based on the the tall deck block. It's been redone and has Crower forged intarnals. The pistons are JE flat top 9.4:1 and the cam is different (Crane Model H-296-2). I've got a Weiand Team G single Plane intake. I intend on taking it apart and refreshing.

A couple of points/questions-
I've got LS-6 heads 2.3" intakes and 1.88" exhausts - any comments on these heads for this motor? Are there mods. that can/sould be done?
I've got a 1050 Holley Dominator - and comments on this? Carb too big? How do you marinize it?

Fred

BigGrizzly
12-17-2008, 06:36 PM
Fred the carb is a good carb but not for that combination. You will find an 825 will do very well.