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347 stroker kit recommendations

blu67

Well-Known Member
I'm planning for a 347 stroker to go into my car when I get her home in a couple of months. I already have the 5.0 roller block prepped but am not sure if buying individual parts or a kit would be best for the rotating assembly. Anyone have a recommendation or thoughts on brand, forged over cast, etc.?
 
You know I always have something to say!

When you say the block is prepped what does that mean? Mains have been lined? Cylinders bored? Block has been clearanced for the longer stroke? The final bore finish should really be done when you have your parts in hand and know what ring set you'll be using. Certain ring materials do better with certain finishes, for example.

You don't need a forged crank for a street engine that is not going to see really high revs for sustained lengths or boost. Price wise you can save a few bucks this way. Do invest in good rod and main bolts or studs. Same thing on the pistons. Do not need to be forged. A hypereutic will be fine and and actually be quieter. At least at start-up. Forged pistons are a tad undersized as the "grow" when heated.

Who will be building this thing? If doing it yourself I still recommend having a good machine shop check the balance on everything for you even though you might have bought a "fully balanced rotating ass'y". There are lots of options. I'd stay away from the mass cheap stuff myself. Most of the big name stuff will do well.
 
So far I have had the block cleaned and magnafluxed, new freeze plugs and bearings, notched for longer stroke and cylinders bored .040 over (there was a damaged piston when I got it) I didn't align hone or deck it as I'm not sure it needed it.
I do plan on likely having someone build it as I want an expert to put it together and possibly provide a warranty if something goes wrong. I'd like to try my hand at building it but since I have never done one before, I'd like it done right the first time....lol
Eagle and Scat seem to be the two main suppliers of the kits...for Summit at least.
 
I used a unbalanced scat 9000 kit (cast crank) for my 331. While it may not be the best, it has served me well. I wanted to do the assembly myself.

Since the balanced kits usually only come with an automatic flex plate, I opted for the unbalanced kit since I needed a 28oz imbalance flywheel (T5).
I also got forged pistons and floating wrist pins. I like the floating pins because they are easy to install the spiral locks with basic hand tools. As stated already, noisy until the engine comes up to temperature.

When I got the kit, the machine shop wanted the full kit (pistons / rods / rings etc...), the block, flywheel and clutch package. As Terry stated, they like to bore and hone according to the piston and ring combination. They balanced the assembly and did comment that the crank required more drilling than expected to get it balanced. Although worried at first, it has held up well with plenty of 6K spurts. outside of the lumpy cam, the engine is super smooth.

Assembling the rotating assembly isn't hard if you have a good clean place to work, good tools are a good study and pay attention to the details. (We know the last point is true), Most shops aren't going to warranty anything unless they do the whole build including first start up. If you really want a warranty, by a ford crate engine. My suggestion would be to have the machine shop take a look at your block and recommend the piston / ring combo, then see if one of the kits provide the same. Let the shop balance and install the rotating assembly. If you want to do some of the build, then do the oil pump, oil pan, timing chain, heads valve train etc... What are you planning for cam and heads?
 
Don't be afraid to assemble it all either. It just takes a little patience to get it right. There is some put it together/take it apart that needs to happen to verify clearances and such. Specialty tools required are not that expensive. The most critical being a quality torque wrench which you could probably borrow (DO NOT USE A AUTOPARTS STORE RENTAL). You could either have the shop fit the rings or you could hand file at home. It's not magic or difficult. There is a certain sense of pride you can only have if you have built your own stuff. To me its worth it and why I try to do it all but everyone has their own goals and limits so do what suits you!

Oh yeah, and plan out your whole combo before you spend any money. That means the complete engine, trans and rear gearing. If it will have a carb get a cam suited to a carb. EFI systems like different profiles. Hone in on final compression ratio. This is usually based on such basic things as fuel you have available. Lower octane means you need to run lower compression. There are a few things you can do in the engine to help tolerate a bit more squeeze but it all needs to be planned in advance. You need to know the full drive train gearing so you can select the proper intake and cam too. Do a lot of research and talk to a lot of guys about their set-ups.

I went with SCAT for the crank and rods (I-beam). Mine is all forged including the Mahle pistons. I had/have visions of putting some boost on it some day so built it to be ready. If I did it again today I would have either forgone the forged stuff or upgraded to an aftermarket block. I'm already at a power level that scares me with the cast block. I think even a little boost might make her go bang!
 
Thanks, guys. I'm not quite sure what I'm going to do. Assemble myself or go with a company. I've never built an engine. I guess I'm just researching right now. Trying to gauge costs as I plan on bringing her home by June or earlier. I don't plan on going to the track and just a simple 347 with EFI is the goal. The trans is an AOD already re-built and ready to go in. The rear is a Currie 9" with 3.50 gearing. I want something that essentially I can get in, start up and enjoy some good, fun street time. With a "penciled" in goal of getting her back on the road by October 2020 (when I turn 50) some stuff I am going to have to farm out since I have a lot to do to reach that goal and I know what I am good at at what will take me much more time for the learning curve.
 
I second the recommendation to build it yourself.

Do some research, and read/watch as many engine assembly instructions/videos as you can stand.

If you start with good parts, and pay attention to detail, you will be amazed at how easy it is to build your own.

And the pride you will feel when you say "oh, I built it myself" is immeasurable, imo.
 
You are welcome. ;)

The dream build I am working on in my mind involves a 347 stroker as well.
 
We got your back, Chris. Hell, you know I build engines all the time for my car. :p Just don't pay much attention to the advise of {.} for obvious reasons.

Come to think of it, I know where a bad ass little 306 is sitting just waiting to be fired up again. It is a nasty little beast too with only about an hours run time on it.
 
I like the idea of putting this together myself and include my son as well because I haven't done one before and it could be a fun project together. I guess I'm a little gun shy on something so important to the car.....
 
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