Keith Black piston rod modification???

[67xr7cat]

So was looking at the KB199 pistons. Says the piston pin is centered and to narrow the rod small end to 1", stock is 1.250".  Looking at other KB pistons they all say the pin is centered, but no note about narrowing the rod.

So anyone know why the rod has to be narrowed? If it is for clearance, then could you just take 1/8" off the one side of the rod?

You would think they would machine the piston for it in the first place!

[67428GT500]

Why would you ruin rods for KB pistons?

[Barry_R]

Must be using a narrow pin boss forging for a BBC application
FE rods are wider
You either narrow the rod or widen the interior of the piston

[67428GT500]

No mention of it being a "stroker". Now that makes perfect sense.

[67xr7cat]

Is a hypereutitic piston for std stroke 427. Is just for a cruiser not race. Just seems strange to make a piston like that.

[67428GT500]

I wouldn't mill the rods. I have never seen that on an OE application either.

[67xr7cat]

Agreed for a off the shelf piston like a kb hyper think not be a custom deal. Taking material away from the piston pin boss will weaken the piston. Guess have to see how wide the pin boss is. Of course narrowing the rod small end would weaken it, but it is a good bit wider than the beam so not sure it matters. About ready say screw it and save up for a stroker it...

[gt350hr]

 NEVER machine the pin bosses on a CAST piston. It WILL fail.
    Buying a cheap set of pistons that require extra cost rod machining didn't save you money. Ford FE rods are wider than they need to be by far and narrowing them will not adversely affect rod small end strength. Carrillo typically uses 1.150 small end rod width on 2,500 hp twin turbo applications. Nascar rods are typically .860 wide now. In the 50+ years I have been doing this , pin end failures on rods are VERY rare.
  Randy

[67428GT500]

Randy, I agree completely with you. However, It makes no sense to me to machine connecting rods in stock applications. Too many offerings and in a 427 why would you run cast pistons anyway?

[67xr7cat]

Guess I should have known better then ask if anyone had experience with this piston. Clearly nobody has any actual hands on experience with this piston.

As to the why I will have all of $240 invested in a new set including moly rings. As for machining the rods I can do that myself so will just be my labor. So in this case I am $$$ ahead and if I decide to go another direction am sure I can find someone who would want then.

Regarding the application it is a street car. Keith black hyper pistons are a well known quantity. The bad rap they got is by people who do not know what they are doing. For the record I am not a fan of hypers, but for what I am doing they will work well.

There is a trend in this hobby towards overkill. I have seen h beam rods and forged pistons fail because of poor work and/or tune up. I've seen stock rods and pistons pushed way further than any sane person would and live.

Anyway I appeaciate the answers, but really don't need the condesending bs, this not my first rodeo. You really never know what someone knows or why they are doing something. This kind of bs is what drives guys away.

[67428GT500]

I don't think anyone is being condescending. They offered opinions. Many of us have been playing with this stuff 40+ years. It makes no sense to modify a factory rod.  With the rarity of the block, I wouldn't run low-dollar pistons period. You already know they're thin and Ford never put a cast piston in a 427.
That says all I need to know. If you're going to throw something out here and you don't like the answers do what you want.  I don't see anyone calling you an idiot or bashing you for lack of knowledge. We like you found it odd that you would have to modify rods for stock replacements, especially on a low dollar cast piston.
I don't see forged pistons as "over-kill" considering the fact that they are so susceptible to bad tunes, poor quality fuels, etc.
Are you a millennial? You sure get offended easily. Stop being so thin-skinned.
                                                                                                                      -Keith

[winr1]

All I could find as you allowed was to narrow the rod small end to 1"

Eagle makes a 6.7 rod with a 1.125 width small end, says good for 700 hp

For a street machine will probably be fine

What are the specs on ya mill if I may ask ??



Ricky.

[67xr7cat]

 Lol no not that young and not thin skinned either. Just as get older no patients for the bs. As I said asked a simple question and nobody here has first hand experience with this piston. When I see the pistons I will be able to determine what the deal is and if they will work for what I want to do. Really not even sure that note about narrowing the rod pin end is accurate. That is really why I asked in the first place.

As for the rest really don't have time for it. Thanks, Steve

[67xr7cat]

All I could find as you allowed was to narrow the rod small end to 1"

Eagle makes a 6.7 rod with a 1.125 width small end, says good for 700 hp

For a street machine will probably be fine

What are the specs on ya mill if I may ask ??
Ricky.

Yes the Molar rod is 1-1/8" too. If I dont use a stock rod think will use the molnar. When I see the pistons will post what the deal is for anyone that may go down this rod.

Is just a street deal. 68 Cougar to 427  c1ae heads with cj valves, bt Mr 2x4, about 10:1 cr, solid cam old ss grind around 250 @ .050. Leaning towards using a tko600. Rear be 4.00 gear dl and about 26" tire.

[67xr7cat]

BTW the Molnar rod is stock fe 6.488. Are a few options, but they do make one that has stock fe specs except small end is 1-1/8". Price wise is about same as an eagle with the arp 2000 bolts. Personally feel the molnar is a better rod. Really nice piece. Steve