Jegs engine for boat repower-gctid350549

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Hey all...

Just got an email from Jegs...

Tell me why this engine won't work for my 86 1950 Capri...

http://www.jegs.com/i/GM-Performance...oductId=753961

I'm aware of the need for brass casting plugs and marine head gaskets... but what else would this need?

My boat would only be used in a lake btw...

KC

[2850Bounty Supporting Member Find all posts View Profile Close 2850Bounty]

You could probably pull this off in a 1950 Capri.

The automotive head gaskets, automotive Circ Pump, and steel casting core plugs aren't an issue if you install a Closed Cooling system.

If not, then these may be an issue.

You'll need a post 1987 153 tooth flywheel.

If Raw Water cooled, you'll want the Marine Circ Pump installed.

The full dished pistons and 9.4:1 C/R are not in your favor, but again, if you're going to pull this off, a 19 footer is the boat to do this in.... not a cruiser.

GM Performance 12568758 - GM Goodwrench 1987-95 350 Truck Engine $1,769.99



Specifications

1. Block: Cast iron, 2-bolt main, 1-piece rear main seal
2. Connecting Rods: Powdered Metal Connecting Rods
3. Pistons: Dished Hypereutectic
4. Compression Ratio: 9.4:1
5. Oil Pump: High-Volume Oil Pump
6. Timing Chain: Morse link-type
7. Camshaft: Flat Tappet Hydraulic (Lift .382" Int/.402" Exh; Duration @ .050" 165.9┬░ Int/174.8┬░ Exh; Lobe Separation Angle 111.9┬░)
8. Cylinder Heads: 65.3cc chambers, 1.94"/1.50" valves, swirl port intake design (heads are not performance-oriented; intended for good bottom end torque and fuel economy; intake runner is restrictive because it has a ramp cast into the bottom of the bowl to promote high swirl)

MichiganMotorz has this 1987-95 Marine 5.7L re-man for $2,199 + shp.



1987-1995 5.7L (350 ci) marine engine (one piece rear main seal, flat tappet cam, mechanical fuel pump pad). This motor has been professionally remanufactured to meet or exceed GM OEM marine engine stock specifications. This 5.7L engine is rated at 228-270 hp at the crank (depending on intake, 2 or 4 barrel carburetor, exhaust manifolds, etc). If you have a 1987-1995 5.7L engine, then this is your exact engine. No modifications need to be made for this to work in your application.

This 5.7L marine engine comes equipped with the following:

ÔÇó5.7L GM marine engine (standard rotation)

ÔÇóCorrosion resistant black urethane paint

ÔÇóCylinder heads, engine block and all internal components

ÔÇóFlat tappet cam shaft (add $200 for roller cam, roller lifters)

ÔÇó5-quart marine oil pan and valve covers

ÔÇóFel-Pro marine head gaskets

ÔÇóHarmonic balancer and circulation pump

ÔÇóOne-Year (parts & labor) Written Warranty

ÔÇóOpposite rotation available for an additional $349 (flat tappet)

.

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2850Bounty wrote:
You could probably pull this off in a 1950 Capri.

The automotive head gaskets, automotive Circ Pump, and steel casting core plugs aren't an issue if you install a Closed Cooling system.

If not, then these may be an issue.

You'll need a post 1987 153 tooth flywheel.

If Raw Water cooled, you'll want the Marine Circ Pump installed.

The full dished pistons and 9.4:1 C/R are not in your favor, but again, if you're going to pull this off, a 19 footer is the boat to do this in.... not a cruiser.

GM Performance 12568758 - GM Goodwrench 1987-95 350 Truck Engine $1,769.99



Specifications

• 1 wrote:
• Block: Cast iron, 2-bolt main, 1-piece rear main seal
• Connecting Rods: Powdered Metal Connecting Rods
• Pistons: Dished Hypereutectic
• Compression Ratio: 9.4:1
• Oil Pump: High-Volume Oil Pump
• Timing Chain: Morse link-type
• Camshaft: Flat Tappet Hydraulic (Lift .382" Int/.402" Exh; Duration @ .050" 165.9┬░ Int/174.8┬░ Exh; Lobe Separation Angle 111.9┬░)
• Cylinder Heads: 65.3cc chambers, 1.94"/1.50" valves, swirl port intake design (heads are not performance-oriented; intended for good bottom end torque and fuel economy; intake runner is restrictive because it has a ramp cast into the bottom of the bowl to promote high swirl)

MichiganMotorz has this 1987-95 Marine 5.7L re-man for $2,199 + shp.



1987-1995 5.7L (350 ci) marine engine (one piece rear main seal, flat tappet cam, mechanical fuel pump pad). This motor has been professionally remanufactured to meet or exceed GM OEM marine engine stock specifications. This 5.7L engine is rated at 228-270 hp at the crank (depending on intake, 2 or 4 barrel carburetor, exhaust manifolds, etc). If you have a 1987-1995 5.7L engine, then this is your exact engine. No modifications need to be made for this to work in your application.

This 5.7L marine engine comes equipped with the following:

ÔÇó5.7L GM marine engine (standard rotation)

ÔÇóCorrosion resistant black urethane paint

ÔÇóCylinder heads, engine block and all internal components

ÔÇóFlat tappet cam shaft (add $200 for roller cam, roller lifters)

ÔÇó5-quart marine oil pan and valve covers

ÔÇóFel-Pro marine head gaskets

ÔÇóHarmonic balancer and circulation pump

ÔÇóOne-Year (parts & labor) Written Warranty

ÔÇóOpposite rotation available for an additional $349 (flat tappet)

.

Why get the pre-vortec? For just $100 more you get the vortec (1996+) which is more powerful and fuel efficient. There are no modifications other than a new intake manifold (~$100-150), which is cheap considering how much more you'll get out of the vortec.

http://www.michiganmotorz.com/vortec...rent-p-68.html

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I was giving him a 1987-95 to 1987-95 comparison................ but good point!

He would then need the Vortec intake, the electric fuel pump and relay system.

KC, you'll get just about as much Bang-for-the-Buck with a good used Duo Prop lower unit.

.

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Thanks guys for all the tip and pointers. I can't believe how much I am flip flopping on the decision of which way to go... but I am leaning toward getting the Jegs motor or go with Rapido. Here's why:

1) I am a rookie boater

2) I'd like to keep the expenses down as much as possible yet still pilot a safe/reliable vessel

3) By going with the pre-Vortec engine, I should be able to reuse most of the accs. from my 305, intake, alternator, carb (re-jetted for the 350), distributor, etc.

4) I'm also learning that boatin' ain't cheap! :-) But will be very rewarding!!!

So that's where I'm at... about 1.5 months away from starting the rebuild... it's gonna be a riot!

Thanks again,

KC

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leedub wrote:
Why get the pre-vortec? For just $100 more you get the vortec (1996+) which is more powerful and fuel efficient. There are no modifications other than a new intake manifold (~$100-150), which is cheap considering how much more you'll get out of the vortec.

http://www.michiganmotorz.com/vortec...rent-p-68.html

Geez.... I just re-read what you said... and now I have more decisions to mull over!!! :livid:

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Dear Rookie, your AQ225E is raw water cooled unless someone has changed it.



Find out if the truck engine is using SS fire ring seals in the head gaskets.

If not, this then becomes a NOT IF, but WHEN the head gaskets fail, you'll be wishing that you'd have gone a different route.

Not just in Salt Water, this will affect them if in River/Lake water as well.

Takes a bit longer, but it will.

.

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Rick,

The boat is raw water cooled (original). Sounds like I better stick with a motor designed for marine use, not the lowest bidder, eh? Alright, alright... Rapido or Michigan??? I know MM is the shin-dizzle (geez, did I just say that)... and even though they are higher priced, it sounds as though they would be the best deal all around.

See... I can learn! :hammer

Thanks again Rick!

[dmcb Founding Member Find all posts View Profile Close dmcb]

Rick, note he is in New Mexico. No salt water there so fresh water cooling may not be needed?

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I wouldn't be against the truck engine in a 19' generally, but I have some additional gripes.

I don't like the cam specs in the jegs engine. The lift/duration is for something towing a load down the highway in overdrive @2000 rpm, not for a boat cruising @ 3500 rpm. Heads are also geared towards this as well.

I'd be looking for a cam with lift in the .435 to .450" range, duration anywhere from 232-270* depending on how comfortable you are regarding water reversion, and something that will offer a dyno sheet with maximum torque around 3500rpm and peak HP ~4800-5000

The H/O cam for an early 70's Camaro with a manual trans will probably get you close. It's got good lift but no excessive duration to risk water reversion or a crappy idle.

By the time you get your jegs engine and put in the good gaskets and correct cam, might as well just buy the marine engine all ready to drop in...

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dmcb wrote:
Rick, note he is in New Mexico. No salt water there so fresh water cooling may not be needed?

2850Bounty wrote:
............ Find out if the truck engine is using SS fire ring seals in the head gaskets.

If not, this then becomes a NOT IF, but WHEN the head gaskets fail, you'll be wishing that you'd have gone a different route.

Not just in Salt Water, this will affect them if in River/Lake water as well.

Takes a bit longer, but it will.

I don't know what the average PH of river or lake water would be, but I doubt that it's suitable for long term use in an engine that has not been built for it.

The scale for measuring pH goes from 0 to 14 with 7 or under representing an acidic environment. Readings over 7 indicates an alkaline environment.

Engine coolant pH below 8.3 pH is not acceptable for use in engines due to its corrosive nature.

The correct pH value should be maintained between 9.5 - 10.0 pH.

.

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For what it's worth... here's where I will boat 99% of the time....

http://www.emnrd.state.nm.us/prd/navajo.htm

[boatworkfl Supporting Member Find all posts View Profile Close boatworkfl]

2850Bounty wrote:
I don't know what the average PH of river or lake water would be, but I doubt that it's suitable for long term use in an engine that has not been built for it.

The scale for measuring pH goes from 0 to 14 with 7 or under representing an acidic environment. Readings over 7 indicates an alkaline environment.

Engine coolant pH below 8.3 pH is not acceptable for use in engines due to its corrosive nature.

The correct pH value should be maintained between 9.5 - 10.0 pH.

.

I used Felpro all fiber marine head gaskets, if using steel then all ports cyl and water need to be SS.

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I just picked up a used VP 280 outdrive, mostly complete, all internals for $75!

Maybe I can use something from it on my VP 275 should it need some repairs...