NA Build - 5.0 coyote rods and flat top hypereutectic pistons

[bhuff30]

I am planning an NA 4.6 build and had a few questions on locating parts.

I was reading that 5.0 coyote rods have the same basic dimensions as the 4.6 rod, in terms of big and little end diameters and center to center distance. They are also quite a bit stronger than stock 4.6 rods. I was reading somewhere that someone had said you could pick up a set for something like 200-250$. Anyone have any idea where? This looks like a great economical solution for an NA build. I don't need to pay for the strength of a forged rod, and this would give me a margin of safety incase I want to spray the engine.

Next is pistons. I want a flat top hypereutectic piston with valve reliefs for the 2 valve... but I haven't been able to find them. I have found flat hypers with no relief, 4 valve reliefs and forged pistons with 2v relief... but no hypers as I want them. Any ideas where to look? The idea is that I don't want to spend a lot of money on forged pistons since I don't need them... plus I can keep the clearances tighter.

 

[vertigasen]

Modular Head Shop has everything you need. The $200 Coyote rods are usually take outs...the new ones are $300. MHS also started having pistons made. Go take a look, they are flat top with real valve reliefs. The rods and pistons would run you about $800.

Flat top hypereutectic pistons are hard to find...for a 4.6...no one wants to make them. You can find forged flat tops all day, hypers...not so much. You could call someone like KB Pistons and see if you could do you a custom set....but that is probably going to cost a whole lot more than the forged.

 

[Rick 91GT]

Im not aware of a aftermarket Hyper 2v piston, forged is the way to go....

How much HP are your trying to make?

 

[bhuff30]

I am looking at around 320-350 rwhp NA, and might spray it with a 75-100 shot when I get bored with that.

I said hypereutectic pistons because I would like to avoid the cost of forged pistons and not have the useless 4v valve reliefs of the 4v pistons (otherwise, stock or stock replacement 4v pistons would be fine).

My basic build is pretty simple:
teksid block
5.0 rods (for a margin of safety instead of worrying about it every time I spray or approach 7k)
PI heads, lightly home ported
MHS stage 3.5 cams
flat tops with 2v valve reliefs
long tube headers
maybe shave the block to make the pistons flush with the deck
Tweecer (or other tuner) burning E85 90% of the time. If pump gas is required, I could detune it by backing off the timing and fattening up the AFs.

All this would go into an FFR cobra. Should be a fun, light weight and potent combo that could still take advantage of mustang ABS, traction control and modern brakes/suspension.