Source for rotating assembly parts and selection advice

r3dn3ck

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I need pistons, rods, bearings, timing set bits, valve train bits, fasteners, gaskets, etc... The build is for high rpm, power band leveling off around 7k and safe rev to 8k with fast rev up and rev down, 11:1 to 11.5:1 compression. I have not determined if I'll need to overbore and I have not decided on going to a stroker or not (thinking not because the cost benefit ratio is upside down). I want I-beam, not H-beam. I'm thinking that 4032 might be a better piston alloy than 2618 since it'll get modest doses of nitrous on rare occasions but won't ever see boost or intensive racing.

DSS has some 4032 slugs for about 650 at Summit. Mahle are an option. Ideas, thoughts, suggestions and links plz.

For rods, everything in the past I've done with H-beam but I think I-beam are better for this application. Suggestions plz.

Link up those super secret squirrel parts depots that deliver the brand name parts without the brand name box. People with parts for sale, hit me up.
 

lwarrior1016

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How much power are you trying to make?

Coyote engines are repeatedly spun to 8k and beyond. They also use the same size rod as the 4.6, so you can use boss 302 rods straight from Ford and be perfectly fine.

I definitely say use 4032 pistons. 2618 will beat the crap out of the bores when they are cold. I’ve use DSS on a couple builds, and they seem to be ok.

I typically go to the normal spots for parts. Modular Head Shop, ModMax, Cushman Motorsports, and MMR are the first ones that come to mind.
 

whiplash473

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If you decide to go with DSS pistons be sure to inspect them. I had to deburr multiple edges on mine.

EDIT: Overall happy with the parts from them. I bought their entire stroker kit.

EDIT #2: Apparently I was less happy with their parts than I remember. I searched back for a thread I made at the time (link below). I do remember a few things about this. 1) The guy I dealt with was very difficult... well... to deal with. 2) This was my first engine build and I made that known. Expressing that I needed to know exactly what I would need for this and had planned on buying everything needed from them. I think I had to drive over there three or four times by the time all was said and done. "oh, you need this" "oh, well duh, you're gonna need that, too."

In their defense, this was ten years ago and things could very well have changed since then. I certainly have.

 
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cobrajeff96

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Sounds like you will need both the rotating assembly and the valvetrain as light as possible. Stroker might not be a good idea considering the piston speeds the engine will experience. The oiling system will have to be on point so plan to spend as much money on it as you can to protect it all. As for fast revs and decel, the afore-mentioned lightweght assemblies are a must but also consider the use of an aluminum flywheel, aluminum driveshaft, and lightened rear gears. Lighter wheels and rotors also help. Basically anything that rotates should be light weight. Something like a McLeod RST will be just fine and still be liveable on the street. But the power number will need to be figured out before any of this.
 
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r3dn3ck

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The difference in piston speeds between a stock and stroker 4v is a nothing sammich. I don't know where people got this notion of piston speeds even being a thing to worry about. The difference between a 3.6" and 3.8" stroke is about 200 feet per MINUTE or roughly 4 feet per second at 8k rpm and we're talking about a base speed of around 80fps so 4fps delta is basically noise compared to the signal. Even the difference between a 4.6L and a 5.4L is all of about 20fps at 8k rpm. So, while 25% is a lot in terms of percentage, the actual piston speeds involved are well inside the zone of nothing special.

I'm considering the GT supercar followers. They're supposed to be better for high rpm applications. Aluminum flywheel will be in use.

No point in the DS or rear end, those don't affect rev speed since their inertia is broken as soon as the car is in motion and they won't appreciably help anyway since they're directly and permanently coupled to high inertia rotating bodies (wheels) and are able to be dynamically decoupled from the part that does the revving.

I started the shopping list over at Modular Head Shop, so far I'm at 3700 bucks and I included Accufab's replacement/upgraded secondary timing chains. I have 2 of every gasket because I'm hooking a buddy up with a set as partial payment for him helping me put my motor together, he has the tools and the clean room.

Just have to add a set of Boss 302 rods and should be ready to start building but before I order anything I need to tear the other motor down and verify that the crank and the bores do or don't need machining and get the heads sent off for a freshening up.
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cobrajeff96

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I don't know, I mean when the car's in motion everything in the drivetrain from front to back could be considered directly connected. I guarantee if you're looking for fast reaction then lightening everything you can will have an immediate and very noticeable effect on the kind of performance you're looking for. For real world example, look no further than the Mustang GTD.

The motor is the only thing spinning everything from crank to the tires and everything in between. The lighter things are, the more power you free up and the quicker the car accelerates/decelerates. Saving static weight is one thing, but saving dynamic (spinning) weight is the cherry on top.
 
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r3dn3ck

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This month's order. I'm having a bear of a time finding a place that I can keep the bloody donor motor while I gather the parts. Hopefully I get paid for that last contract gig soon and I can shortcut the whole thing, buy all the remaining parts and send it off for assembly. I was seriously about to order pistons and bearings but I want to pull the motor apart beforehand to see if I'm going to have to cut the bores or bearing saddles or crank journals.


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