WELCOME TO RIVER DAVES PLACE

Time for a rebuild...

Croz

Well-Known Member
Joined
Feb 25, 2014
Messages
921
Reaction score
1,453
I’ve got a ‘92 454 mag in my 210 that’s carbureted with about 900ish hours on it, I want to rebuild it before it goes boom because it’s slow and not snappy to fire up, pings in a higher RPM, and is just all around tired. So I would love some input please..


Was thinking of adding a Holly Sniper EFI system to replace the carburetor so my starter doesn’t get put through hell every trip, does anyone have experience with this product yet?

Also what would it cost(ballpark) to have it rebuilt at a shop? I’m hoping to add some horsepower but not trying to break the bank.

Anyone have a rebuilt or new motor for sale? Thanks in advance
 

Bigbore500r

Well-Known Member
Joined
Apr 28, 2014
Messages
17,360
Reaction score
35,090
I’ve got a ‘92 454 mag in my 210 that’s carbureted with about 900ish hours on it, I want to rebuild it before it goes boom because it’s slow and not snappy to fire up, pings in a higher RPM, and is just all around tired. So I would love some input please..


Was thinking of adding a Holly Sniper EFI system to replace the carburetor so my starter doesn’t get put through hell every trip, does anyone have experience with this product yet?

Also what would it cost(ballpark) to have it rebuilt at a shop? I’m hoping to add some horsepower but not trying to break the bank.

Anyone have a rebuilt or new motor for sale? Thanks in advance

Running a sniper EFI setup would be simple, except for the 02 sensor placement. You will need to have a 02 sensor location in your exhaust stream that stays dry. That might require a different exhaust manifold setup, or possibly yours can be modified by somebody who knows how to set it up properly to keep the 02 sensor happy. You will need an electric fuel pump and regulator to run the required fuel pressure, and to route a return line back to your tank(s)

A stock rebuild for a 454 in decent shape can be done for $2000 and up, assuming your crank, rods and block can be re-used. The sky is the limit once you get in there.... Forged pistons, better heads......etc are all gonna crank that budget up exponentially.
 

D19

Well-Known Member
Joined
Aug 13, 2018
Messages
2,296
Reaction score
4,489
I wouldn't do the EFI. Too much money and hassle for not enough reward. Put an electric pump on it if you want better fuel pressure when cranking. You'll need an electric pump if you go EFI anyways, might as well start there.

The pinging could have something to do with the ignition system or bad fuel.

Like BB500 said, you'll need to run returns for an electric pump. Your tanks might need to come out if so to weld in the ports. You also want to return fuel to the same tank you're currently drawling from. You'll need a electric valve or two manual ball valves dedicated to each tank.
 

mesquito_creek

Well-Known Member
Joined
Sep 25, 2009
Messages
3,622
Reaction score
5,993
I just have to ask.... Is it really "tired" or you have just changed your impressions of how it runs. Slow start and some high rpm detonation is not nessesarily anything to do with the rotating assembly. Also is 900 hours on that motor about 1/2 way done and not finished? I am all about building it for more HP, but unless your wife reads the forums and you want your story to be consistent is it really a rebuild problem?
 

Bigbore500r

Well-Known Member
Joined
Apr 28, 2014
Messages
17,360
Reaction score
35,090
I just have to ask.... Is it really "tired" or you have just changed your impressions of how it runs. Slow start and some high rpm detonation is not nessesarily anything to do with the rotating assembly. Also is 900 hours on that motor about 1/2 way done and not finished? I am all about building it for more HP, but unless your wife reads the forums and you want your story to be consistent is it really a rebuild problem?
I've heard the old carbed Merc 454's practically run forever with care. They don't rev high, or run big spring pressure. I'd do a compression and lead down test, and if it's good have the distributor timing and curve checked, fresh plugs with correct gap, new wires, and get that carb running proper
 

Cole Trickle

Member
Joined
Sep 25, 2007
Messages
23,477
Reaction score
15,822
Keep it simple shit snowballs really fast....Bigger engine and more hp and you are now going external steering,extra cooling , drive issues,etc....

Barry would be a good place to go for a rebuild if you can pull and reinstall the motor. After that perhaps a trip to see Alexi at boostpower for a prop dyno/Tuning session.

Go through everything make it fresh perhaps a new cam and some head work , dial it in and go enjoy.
 

D19

Well-Known Member
Joined
Aug 13, 2018
Messages
2,296
Reaction score
4,489
I've heard the old carbed Merc 454's practically run forever with care. They don't rev high, or run big spring pressure. I'd do a compression and lead down test, and if it's good have the distributor timing and curve checked, fresh plugs with correct gap, new wires, and get that carb running proper

Yes. All of this should be step one unless he just wants to rebuild an engine merely for the sake of rebuilding it. Rebuilding should be the last resort lol
 

HST4ME

Well-Known Member
Joined
Nov 9, 2015
Messages
6,579
Reaction score
14,653
The sniper kit is nice since they offer a Rochester kit. The 02 sensor isn't terrible to do. Start with exhaust for parts . it's not difficult to make 450 hp with stock cruiser hard parts and a cam with exhaust upgrade.
 

OLDRAAT

inadequate member
Joined
Oct 3, 2007
Messages
2,617
Reaction score
4,068
One of my boats has an '88 gen 4 big oval port with 1362 hrs. Never been busted open, just sensible maintenance and a few replacement parts.
Runs within 2 to 3 mph as it did 32 years ago :)
 

Shrub Lurker

Well-Known Member
Joined
Oct 5, 2018
Messages
958
Reaction score
833
How fresh is that carburetor. I have had great luck with Edelbrocks marine units. At 900 hours and that age, I’d throw $500 at a new unit from summit or other internet source (there are small model 1409, and big block model 1410 units offered). They require minimal adjustment once installed and this time of year you can find deals.
 

Shlbyntro

Ultra Conservative
Joined
May 27, 2018
Messages
7,744
Reaction score
22,543
How fresh is that carburetor. I have had great luck with Edelbrocks marine units. At 900 hours and that age, I’d throw $500 at a new unit from summit or other internet source (there are small model 1409, and big block model 1410 units offered). They require minimal adjustment once installed and this time of year you can find deals.

Keep the original carb on it and rebuild it. It drives me crazy when people nonchalantly just throw another carb on it. That factory carb is jetted and setup for your engine.
 

Trash

Well-Known Member
Joined
May 9, 2008
Messages
847
Reaction score
331
EFI is a significant improvement. Biggest downside is the initial cost. But...once you have the EFI system it can be used on virtually any motor should your tastes change down the line.
 

Riverbottom

Well-Known Member
Joined
Oct 30, 2007
Messages
2,338
Reaction score
2,510
Did anyone mention Barry. I would give him a call, all around good guy.
 

Riverryder

Well-Known Member
Joined
Aug 15, 2019
Messages
3,456
Reaction score
3,651
Run it till it blows. Buy another motor in mean time and build it. That’s what I’m gonna do! I have a 454 in mine with some work. But I am gonna do a efi motor next
IMG_0293.jpg
Adjustments.jpg



Sent from my iPhone using Tapatalk
 

obnoxious001

Engine building character
Joined
Dec 28, 2007
Messages
6,464
Reaction score
3,815
Barry @ Obnoxious recommendation X5

Thanks Jason and all others who mentioned me. My first thoughts are that a properly tuned engine will fire up easily with a carburetor, so as mentioned above it would make sense to test and see if the engine is truly worn enough to justify pulling for a rebuild.
 
Top