1997 5.7L thunderbolt ignition. Slow crank

nola mike

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That's why I keep asking @Scott Danforth comment
It's my assumption that the later Gen "might" (note the might) not have the block opening. I can do the research but Scott knows it
Oh, I misunderstood you. Thought you meant that if he went vortec would need an electric pump. Yeah, my 2001 4.3 doesn't have a port either.
If it's a 1996-2000 block. The pad is there, not machined

It can be machined with a mill. I would try a bastard file and a die grinder if it was a pinch
What would drive the pump? Assuming the cams changed...
 

findinghomer

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The 2BBL isn't an issue but the manifold is, the Mans have different bolt patterns

Assuming you have a mechanical fuel pump so you would need to go electric


Oh so my intake manifold will NOT work? A I I've read it would just trying to get the right answer. The reason I was asking about the manifold is my manifold has round ports for the carburetor to bolt on to, the other ones for vortec look completely different, They look rectangularly which I figured I would have to get a different carburetor, sorry if these questions sound stupid this is all new to me. Starting to understand it all I just need to know these few extra questions before I pull the trigger, because I won't have anybody in the real world to help me.

This is what my intake manifold looks like vs the when I Google 2bbl voretec. So what you were saying is I can take my my two barrel carburetor and an electric fuel pump to it, I'm not really hung up on the whole manual fuel pump I was just trying to make it as bolt-on accessible as possible, if I need to add an electric fuel pump I suppose I could figure that out. Thanks Scott!

Oh and also the cam, what cam should I get exactly? And where do I find it? I also read that if it was for a truck the cam would be fine
 

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findinghomer

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Oh, I misunderstood you. Thought you meant that if he went vortec would need an electric pump. Yeah, my 2001 4.3 doesn't have a port either.
What would drive the pump? Assuming the cams changed...
I mean if it means taking it to a machine shop and having to have it machined, I'd rather just add the electric pump if it's not that big of a deal. I'm not hung up on themechanical fuel pump, I just wanted it to be compatible as possible with my old engine, So I can swap all my Marine parts over and drop it in
 

Scott Danforth

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That is a vortec 2-barrel manifold in the pic

8 vertical manifold bolts = vortec

Non vortec manifolds have 12 bolts
 

findinghomer

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That is a vortec 2-barrel manifold in the pic

8 vertical manifold bolts = vortec

Non vortec manifolds have 12 bolts


Oh okay, I got you yeah mine had six bolts per side, so if I were to buy that motor my manifold would not work. I would have to buy a new manifold, but I could still use my carburetor if I bought that manifold pictured.. Then I would just have to add an electric fuel pump, I also came across another Marine engine that I think includes all of that,

https://www.rapidomarine.com/default.aspx?p=/complete_engines.aspx

that might be a better deal now that I'm I'm starting to have to piece prices together of different things I would have to change for my current setup. And I really don't understand the whole cam thing I've just searched Marine cam and I don't really come cross anything. I thought everything from my my Non vortex was going to cross over


Ohhh. What about flywheel and engine coupler will those bolt onto the vortec?
 
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Scott Danforth

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All SBC motors after 1985 have a 1-piece RMS crank

Nothing really special about vortec other than the combustion chamber and the roller cam

If youre looking for a great starting point. Find a wrecked low mileage 1996-2000 pickup truck motor or the 1988-2004 3/4 ton vans.

A few low mileage ones on car-part

Swap the core plugs, and head gaskets and migrate the FEAD from your current motor over
 

findinghomer

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All SBC motors after 1985 have a 1-piece RMS crank

Nothing really special about vortec other than the combustion chamber and the roller cam

If youre looking for a great starting point. Find a wrecked low mileage 1996-2000 pickup truck motor or the 1988-2004 3/4 ton vans.

A few low mileage ones on car-part

Swap the core plugs, and head gaskets and migrate the FEAD from your current motor over.
What's FEAD? I only found a couple under 100k and they want 1500+2k that's why I was going to go reman, And then migrate my Marine parts over to that engine. But now it looks like the intake manifold won't work, so I'd have to get one of those, I got those priced at 500 to $600 new. . Which puts me about $3,400. The one company had a complete engine with the intake manifold , new distributor carburetor etc and all that for 3700. And I'm assuming that one will have the head gaskets in cam already because it's actually a marine engine.

I posted that one above
 

nola mike

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Wow, was looking over at michiganmotorz... things have become crazy expensive!
1. I personally wouldn't sweat getting a higher mileage engine. My 4.3 had at least 200k when I pulled it 5 years ago ($180). If the compression is good, you're set for a while at least. This would at least give you time if you wanted to rebuild yours. The swap can be either very simple or a bit more complicated, depending on how much you'd want to upgrade.
2. The vortec heads will probably be on whatever used engine you get (newer) and not cost any more. You'd need an intake, not a huge deal. Roller cam and (not sure when?) roller rocker would be benefits of a newer engine.
3. You could also upgrade to a 4 bbl carb while you're at it...
4. FEAD = front end accessory drive (assuming you have a serpentine belt on that vintage)

No matter what, you'd be able to use at least most of your accessories. Already having a serpentine belt system on there simplifies a lot, your flywheel/coupler should bolt right on. Only issues would be the fuel pump as mentioned earlier, and possibly issues with mixed metric/SAE fasteners (not sure when that stupid transition occurred, @Scott06 I think dealt with that, as did I).
 

Scott06

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Wow, was looking over at michiganmotorz... things have become crazy expensive!
1. I personally wouldn't sweat getting a higher mileage engine. My 4.3 had at least 200k when I pulled it 5 years ago ($180). If the compression is good, you're set for a while at least. This would at least give you time if you wanted to rebuild yours. The swap can be either very simple or a bit more complicated, depending on how much you'd want to upgrade.
2. The vortec heads will probably be on whatever used engine you get (newer) and not cost any more. You'd need an intake, not a huge deal. Roller cam and (not sure when?) roller rocker would be benefits of a newer engine.
3. You could also upgrade to a 4 bbl carb while you're at it...
4. FEAD = front end accessory drive (assuming you have a serpentine belt on that vintage)

No matter what, you'd be able to use at least most of your accessories. Already having a serpentine belt system on there simplifies a lot, your flywheel/coupler should bolt right on. Only issues would be the fuel pump as mentioned earlier, and possibly issues with mixed metric/SAE fasteners (not sure when that stupid transition occurred, @Scott06 I think dealt with that, as did I).
The 090M 4.3 (M for metric) were used in early 2000s, yes unexplainable mix of metric threads on side motor mounts , starter bolts, and flywheel cover fasteners, SAE for the rest
 

findinghomer

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Wow, was looking over at michiganmotorz... things have become crazy expensive!
1. I personally wouldn't sweat getting a higher mileage engine. My 4.3 had at least 200k when I pulled it 5 years ago ($180). If the compression is good, you're set for a while at least. This would at least give you time if you wanted to rebuild yours. The swap can be either very simple or a bit more complicated, depending on how much you'd want to upgrade.
2. The vortec heads will probably be on whatever used engine you get (newer) and not cost any more. You'd need an intake, not a huge deal. Roller cam and (not sure when?) roller rocker would be benefits of a newer engine.
3. You could also upgrade to a 4 bbl carb while you're at it...
4. FEAD = front end accessory drive (assuming you have a serpentine belt on that vintage)

No matter what, you'd be able to use at least most of your accessories. Already having a serpentine belt system on there simplifies a lot, your flywheel/coupler should bolt right on. Only issues would be the fuel pump as mentioned earlier, and possibly issues with mixed metric/SAE fasteners (not sure when that stupid transition occurred, @Scott06 I think dealt with that, as did I).
Okay thanks for all that info. I think I've got it narrowed down to The Marine long block I posted above that already has the intake and the carburetor upgrade and fuel pump I would just have to add my manifolds and risers . Obviously it will be my most expensive option but for my skill level it would be something I could just drop in and not be confused with what I need.

However I haven't completely written off putting a used engine in, the only thing that gets me is this whole cam stuff. If I get one off of a heavy duty truck wouldn't it already have the proper cam? I can change the head gasket just not sure about the cam

If I did that, I would just strip off all the front end accessories from the truck , add a marine intake manifold, All of my Marine front end accessories like power steering water pump, alternator and starter , copper plugs and it should be good right? Except for maybe putting a new distributor and wires and all that. The fuel pump on a used engine would still be Used with my car?

I guess my easiest option would be to buy a remand non-vortec and just bolt everything back on from my old engine.. I do like the idea of upgrading to a vortec I'm just getting anxious that it might be over my head
 

Scott06

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I bought a partial engine from Michigan motorz in 2016. New base engine, intake, carb, ignition , wiring harness and fuel pump. Just added exhaust and my accessories from old engine. No guess work and has been trouble free for a decade plus now. Sometimes spending more up front is better.

And agree 100% truck cam and marine cam are basically the same if you get a wrecking yard engine.
 

nola mike

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However I haven't completely written off putting a used engine in, the only thing that gets me is this whole cam stuff. If I get one off of a heavy duty truck wouldn't it already have the proper cam? I can change the head gasket just not sure about the cam


If I did that, I would just strip off all the front end accessories from the truck , add a marine intake manifold, All of my Marine front end accessories like power steering water pump, alternator and starter , copper plugs and it should be good right? Except for maybe putting a new distributor and wires and all that. The fuel pump on a used engine would still be Used with my car?

I guess my easiest option would be to buy a remand non-vortec and just bolt everything back on from my old engine.. I do like the idea of upgrading to a vortec I'm just getting anxious that it might be over my head
As mentioned you didn't need to mess with a cam. You need a marine fuel pump. Then yes just switch your stuff over. Wiring will be a straight swap as well. Vortec isn't any harder since you'll be pulling heads and manis anyway.
 

Scott Danforth

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here is my typical starter and electric fuel pump wiring.

verify the oil pressure switch connections, they are not standardized between brands. The relay connections are standardized.

with "0" oil pressure, cranking the motor provides priming and ignition
with over 3psi of oil pressure, ignition and fuel pump run on the FPR and no cranking is available.

with falling oil pressure, it kills the ignition and fuel saving the motor and killing the fuel supply
1784654124998.png
 
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