engine for a 2452 cruiser...-gctid403118

[Guest]

thank you for all the input. IShowed all the comments to my son and he got the picture, so, he sold the 4.3 to to a fellow firefighter that has a s/r that is in need of a 4.3 . now he wants dad (me) to build what I originally proposed, a simple mild 355 ci engine , and yes rick it will be a q/e build. i thought about a 383 but just do not like the rod angle at the bottom of the stroke, it's my opinion at that position the rod puts undo pressure on the pin by trying to push it out the side of the bore thus resulting in premature piston wear.:thumb

thanks everyone,

pat

[2850Bounty]

HeadinSouth wrote:
.............. now he wants dad (me) to build what I originally proposed, a simple mild 355 ci engine , and yes rick it will be a q/e build.

i thought about a 383 but just do not like the rod angle at the bottom of the stroke, it's my opinion at that position the rod puts undo pressure on the pin by trying to push it out the side of the bore thus resulting in premature piston wear.

Pat, that can be somewhat of an issue with 3.750" stroke with the typical 5.7L block crank-to-deck dimension.

The automotive guys go with the longer rods, but that moves the wrist pin higher making for shorter piston skirts that can pose an issue with the Marine version.

With our lower RPM, I don't necessarily see the shorter rods as being a deal breaker.

Ford was pretty smart by making their 335 series 5.8L deck height taller than the 5.0L.

I think that the .030" over GM 5.7L will do just fine!

[captharv]

Keep two things in mind when building for power:

First as mentioned, the power capibility of the drive. Pre-alpha were blowing gears whne used with a 5.7 4BBL in 26' cruisers. Thats why merc made the alpha.

Second, and this is a biggie. In a vehicle, you may use all the HP to get to hiway speed. Once there you may only use 20-30 to keep it there.

In a vessel, if 150 HP is required to maintain a cruising speed, then you will use 150 HP constantly

The 5 times increase in HP usage created more heat and wear on the engine. Tricking out the engine may shorten its life.

However, changing a 2 BBL to a 4 should not cross into being undependable.

Lazycruiser: to change the carb into a 4 BBL, you will need to source:

MARINE 4 BBL

Manifold to fit the engine

any necessary adaptors/extra pieces to use the fuel line and throole cables again

gaskets for engine to manifold

Labor:

Remove the distributor. and mark as to the orientation of it

remove carb from manifold

remove manifold

clean up the intake ports on the heads

put gaskets on heads

install manifold, being very careful to have it perfectly centered on both heads, and torque down

Install distributor, align as noted above

install carb with proper gaskets under it

connect fuel line

connect throttle cable

With all spark plugs removed, crank engine and set timing using a timing light

preset idle mixture screws to spec

Reinstall plugs, and start engine

Adjust the mix screws evenly for idle.

If easy if you have done it before, or someone, who has, standing in back of you (thats how I learned).

Here in central florida there was a shop who sold used engines, and used parts. You could buy the carb and manifold used, and save a lot of money, maybe enought to hire someone to install it.

maybe someone up your way does this?

[Guest]

Hi Pat.

I own the exact same boat that your son is looking at purchasing. The 2452 is a great all around family cruiser/fishing boat, and with the 5.0 it is ok but it is a little underpowered when fully loaded with fuel, fresh water, gear, passengers, and then pulling skiers and tubes. Go with the 5.7 when looking for an engine. I purchased my boat last fall for $4700.00 pretty much ready for the water. Engine and drive needed maintenance only and some minor repairs. The boat I purchased came equipped with dinghy davits, electric fridge, electric windlass, HDTV antenna, vhf, no trailer. I don't know what the market is like in your area but negotiate hard and you should be able to get it for a good price if it needs and engine. Look carefully for other issues for further negotiating points.

Good Luck

Matt

[Alaskanmutt]

CaptHarv

You forgot the most important thing.

Don't Drop anything down any of the holes............

[Guest]

V6 will have very hard time getting out of the hole under ideal conditions. Forget about it if boat has gas, water, and passengers loaded.

[Guest]

captharv wrote:


Lazycruiser: to change the carb into a 4 BBL, you will need to source:

MARINE 4 BBL...

...You could buy the carb and manifold used, and save a lot of money, maybe enought to hire someone to install it.

maybe someone up your way does this?

Let's clarify...ONLY use a marine carb. Do not make an exception here. Used or not, do not use a regular automotive carb.

I also agree, 4.3L=Bad idea.

[Dadrock33]

LazyCrusr wrote:
Would it be a huge project to put a 4 barrel on my boat?

5.0, 2 barrel now

In my opinion, you heard right.

Have yet to get a really good look at the engine but understand that the 2 barrel was standard on the 5 Ltr - would the 4 barrel be a good investment to help increase the "outa-the-hole" performance? Have the Mirage Plus prop (17P) and was just about to drill out the plastic plugs to see if that would help (there are 3 hole sizes to drill or you can replace the plugs with OEM parts if you can find them) but haven't talked to or heard of anyone having a lot of luck in that area.

Yep, she be a doggy getting up on plane . . . . looking at different options now. With the "above" prop, I'm at about 25 mph while at 4700 rpms - don't know if that is good or bad yet . . . . just bought the boat and haven't had much of a chance to "play with things".

[Guest]

One thing to note about the four-barrel conversion, this only helps if you have the Vortec heads!

[Chief_Alen]

Too many questions from different people, just sayin... ask a question in a sep. thread.

OP...That 5.7l in the garage you have a truck engine ? Or a engine from a car.

[dktool]

Too many questions from different people, just sayin... ask a question in a sep. thread.

OP...That 5.7l in the garage you have a truck engine ? Or a engine from a car.

answer is ......................

I have a 5.7 gm truck engine in my garage

[Guest]

2850Bounty wrote:
Pat, that can be somewhat of an issue with 3.750" stroke with the typical 5.7L block crank-to-deck dimension.

The automotive guys go with the longer rods, but that moves the wrist pin higher making for shorter piston skirts that can pose an issue with the Marine version.

With our lower RPM, I don't necessarily see the shorter rods as being a deal breaker.

Ford was pretty smart by making their 335 series 5.8L deck height taller than the 5.0L.

I think that the .030" over GM 5.7L will do just fine!

Nope, not a deal breaker, but short skirts and long rods is a deal breaker for me.I dont like when they move the pin into the oil ring and leave the oil ring un-supported also, the short skirt makes the problem I described 100% worse, imo.I started scrounging parts yesterday at a swap meet pickup a good pair of almnum heads yesterday fo under $20.00 I have a lead on a few 1350 hp pro stock engines , but I think that might pose more problems than I care to address. I'll keep scrounging around until I get what I want.

pat

[2850Bounty]

HeadinSouth wrote:

• 1 wrote:
• Nope, not a deal breaker, but short skirts and long rods is a deal breaker for me. I dont like when they move the pin into the oil ring and leave the oil ring un-supported also, the short skirt makes the problem I described 100% worse, imo.
• I started scrounging parts yesterday at a swap meet pickup a good pair of almnum heads yesterday fo under $20.00

• 1 wrote:
• Same here, Pat....... I would not do long rods nor short skirts for the Marine 383.
  
  However, raising the pin height and using a longer connecting rod does reduce some of your side load concerns.
• If you go with the aluminum cylinder heads, this becomes all the more reason for a good tight quench.
  
  Our member Dave M. (aka Yachtman) can fill you in on the different aluminum cylinder heads.

[Guest]

dktool wrote:
answer is ......................

DKTool, you are making sure we paying attention!

[Chief_Alen]

Yes he is.