5.0 to 5.7 swap. what parts are interchangeable

[snowman51789]

Hi, i am looking at buying a new boat, its a 1990 wellcraft eclipse 216. its exactly what i want however the only problem is it has a 5.0 mercruiser instead of the 350 or 454 that i want, i am dead set on one of those motors because the boat i have now is underpowered (in my opion) and i hate it. so if i were to swap the 5.0 for a 5.7 what parts can i take off the 5.0 and use on the 5.7, i know stuff like like the alternator can be swapped, but here is a list of stuff i want to know about

intake/exhaust manifold
carburator
heads
valve covers

any other advice would be great, ive never done anything like that so if you can think of something else i should know it would be a big help. and also do anybody kno of any good website so i can get a rough estamate on how much this will cost??

thanks

Dave

 

[Bondo]

Re: 5.0 to 5.7 swap. what parts are interchangeable

Ayuh,.... The 305, 'n the 350, if of the same vintage, are Exactly the same, on the outsides of the block....

Only their Internal parts are different...

305 Heads, will bolt onto a 350, but run like crap, because of increased compression, 'n tiny valves...
350 heads on a 305 run like crap, because of lowered compression, 'n shrouding of the bigger valves...

 

[snowman51789]

Re: 5.0 to 5.7 swap. what parts are interchangeable

Yeah I want to do this right the first time. So I need to get the heads, how about the intake and exhaust manifolds?

 

[Bondo]

Re: 5.0 to 5.7 swap. what parts are interchangeable

Yeah I want to do this right the first time. So I need to get the heads, how about the intake and exhaust manifolds?

Ayuh,... The Intake manifold has to match whichever heads ya use...

The exhaust manifolds don't care, they're not internal parts...

 

[John_S]

Re: 5.0 to 5.7 swap. what parts are interchangeable

You are looking for more power, so should go to a vortec head 350, and that would require a new intake. Carb, if a 4brl, will need some tuning/adj (or replacement) for the 350.

 

[snowman51789]

Re: 5.0 to 5.7 swap. what parts are interchangeable

Dose anybody kno of any place that sells motors with out the bolt ons?

 

[greg82255]

Re: 5.0 to 5.7 swap. what parts are interchangeable

Rapido marine has a good reputation on this site. I'd give them a call and see what they can offer you. When I called them maybe 6 months ago they wanted $1850 for a vortec 350 long block. It's probably slightly higher than that now, as their other prices have gone up too.

 

[81 Checkmate]

Re: 5.0 to 5.7 swap. what parts are interchangeable

Is there something wrong with the 305 to make you what to change it out? If nothing then you must have money to burn. Goggle search new and recondition chevy small blocks and it will lead you to a rhelm of things.

 

[dubs283]

Re: 5.0 to 5.7 swap. what parts are interchangeable

if the boat is exactly what you want except for the engine and you are dead set on a different engine, why don't you just buy a similar boat with a 350??

there are a lot of other boats of that vintage that are very similar to a 21' wellcraft with 350's

 

[billbayliner]

Re: 5.0 to 5.7 swap. what parts are interchangeable

I read where Michiganmotorz is willing to build a 5.7L or 6.2L Vortec or non-Vortec with a quench into their build [not using the full dish piston]. May be worth giving them a call.

 

[billbayliner]

Re: 5.0 to 5.7 swap. what parts are interchangeable

Dave, you say that the 1990 wellcraft eclipse 216 is exactly what you want. That makes the new engine understandable. Go for it, and enjoy the boat!

 

[snowman51789]

Re: 5.0 to 5.7 swap. what parts are interchangeable

the problem with finding another boat is that there are not that many out there that dont need lots and lots of work to make them a nice boat. im not dead set on an eclipse, that was just my favorite and this one happen to come along and its in exelent shape. thanks for all the input, as of now my plan is to buy the boat, see if the 5.0 performs like i want it to and if it dose then im going to keep the motor, however im not going to hesitate to swap the motor. thanks every one. the input and advise was a big help.

 

[7362]

Re: 5.0 to 5.7 swap. what parts are interchangeable

Gosh I just did what you are talking about. I have Wellcraft Eclipse 215. I blew my 305 vortec block, I threw a connecting rod at high rpms- sigh...-see photos. A tough day, but a good one for Sea tow.

In any case, everything came apart easily,. and I had access to a forktruck to lift out the bare engine. All bolt on externals swapped over to my 350 marine block, the block is the same exernally. (water pump mainfolds, alt, power steering pump, It was time consuming and a fairly big job. I am still working out a fuel delivery problem. The refurbished stock quadrajet stock carb worked very poorly, and I upgraded to Edelbrock. Still need to address a flooding issue . In any case

Some notes:

Be sure to get a marine block. Many folks call their block marine, but it has different materials and better durability than a truck block. Do you homework and find someone reputable.
Be sure to check the engine coupler, rear motor mounts, for wear. I had to replace mine. Keep me posted and feel free to ask any questions.

Replace the shift cable since everything is apart anyway,and its cheap,too.

 

[jopes]

Re: 5.0 to 5.7 swap. what parts are interchangeable

Some notes:

Be sure to get a marine block. Many folks call their block marine, but it has different materials and better durability than a truck block.

everything I have heard is this is untrue. There is no difference in marine, truck or car castings. Just gaskets, water pumps, freeze plugs and cam.

 

[smokeonthewater]

Re: 5.0 to 5.7 swap. what parts are interchangeable

historically there have been a VERY few marine specific castings BUT mercruiser 5.7 chevys are not in that group.
car, truck, boat.... makes no difference.

 

[Captain Nemo1]

Re: 5.0 to 5.7 swap. what parts are interchangeable

Snowman, the Eclipse is a cool boat. You go guy!

 

[jumpjets]

Re: 5.0 to 5.7 swap. what parts are interchangeable



Very cool! I haven't seen many other people at all with the same type of boat that I have. It is my first boat and it is an absolute hoss. It's very durable. I have a 350, and I wish it had just a touch more power. It is wise of you to swap out the 305. WIth my stock 350 and a 19 pitch 4 blade prop, I can get 43mph GPS on calm water when I'm flat out.

Sorry to hijack your thread, but what kind of truck are you planning to towing it with? I'm using a ford explorer v6, and I think I'm right at the limit of the truck. I haven't weighed my boat yet.

 

[snowman51789]

Re: 5.0 to 5.7 swap. what parts are interchangeable



i have an 04 f150 with a 5.4 v8 in it that im going to tow it with. i dont think i will have anybroblem buy im sure i will only get around 12mpg with it, if im lucky, i did end up buying the boat, but i have to wait 3 weeks to get it because its in storage and they cant get it out yet. how many people can you get on your boat? thats my biggest concern, i plan on having 5-7 people on it, but i am going to put trim tabs on it to help it out.

PS ur not hijackin my thread, ive been wanting to talk to somebody that has an eclipse 216

 

[snowman51789]

Re: 5.0 to 5.7 swap. what parts are interchangeable

oh and 7362, roughly how much do you have into your motor swap? if you dont mind sharing.

thanks

 

[Bondo]

Re: 5.0 to 5.7 swap. what parts are interchangeable

Originally Posted by 7362

Some notes:

Be sure to get a marine block. Many folks call their block marine, but it has different materials and better durability than a truck block.
Do you homework

everything I have heard is this is untrue. There is no difference in marine, truck or car castings. Just gaskets, water pumps, freeze plugs and cam.

historically there have been a VERY few marine specific castings BUT mercruiser 5.7 chevys are not in that group.
car, truck, boat.... makes no difference.

Ayuh,.... I've done the homework,.... I'm jumpin' on the bandwagon,....

That's Bull, generally speakin'....

Excludin' some odd-ball Chris-Craft castin', or Racin' stuff....