building specs for the 6.9L

[xcite]

Something else I would strongly recommend is to cryo treat all the internals. That will add even more strength and rigidity to them. It would also help with heat resistance too. There is a thread I posted about cryo treating a few days ago. Look it up. It has a good link in it. Also I would definitely coat the pistons too.

As for the pistons, I really don't think those pistons will handle the heat of an IDI very well. I would at a minimum get the pistons from Mahle. And as for the compression drop, there is a guy on another site running 18.5:1 and is pushing 36psi into it. The last dyno before he added more fuel and changed his turbo he dynoed at 292/614. He is a bit higher than that now.

The guy running 292/614 used silvolite pistons in his build because they are stronger from the start and he also cryo'd and coated them.

 

[88 Ford]

I would still recomend silvolite pistons they have a much better alloy they are made out of, and a tri-coat on them will make them even tougher.
I would highly recomend updating the cam at this time to something more turbo friendly. One from typ4 on this forum for lower rpm torque, or a J2 cam for higher reving. Depending on cam regrind may need longer pushrods.
I wouldnt decompression the engine unless you are planning on making your oun custom turbo system. The standard bolt on turbo kits for these engines will not work very well with a decompressed engine. To do anything to the pistons you need to know what you are going to do for turbo, bolt on kit or custom setup, this is one item you really have to plan ahead for.
I would leave the oil cooler alone, but remote mounted oil filtering could be a big plus.
Frost plugs on these engines can be a pain, make sure they are stainless steel or go all out and tap for pipe plugs and problems are over.
When putting finishing touches on engine go with a turbo cal pump or moose pump for better fueling.
Definetly plan on an intercooler when completing the project it will be well worth the effort.

X2! Xcite said it well. The KB Silvolite pistons are good pistons. And definitely get the cam. It is night and day difference.

Also as for the fuel, you could go turbo cal or Moose OR you could step it up even more on the fuel and upgrade to a Db4. With the mods you are doing, you will be able to handle both the extra fuel and quite a bit more boost...

 

[88 Ford]

The guy running 292/614 used silvolite pistons in his build because they are stronger from the start and he also cryo'd and coated them.

Yep exactly. It will be cool to see what he dynos on the 18th.

 

[TahoeTom]

I just sent a set of pistons to Calico Coatings in Denver, North Carolina. The machine shop I am using said their coatings stay on rather than flake off. Cost for ceramic crown and anti friction skirt is $321.60. 2 or 3 day turnaround. I think the sealed power pistons already have the skirts coated, so you would only need crowns done. Figure around $70 round trip UPS ground shipping, one week each way.

 

[typ4]

I would use the original oil pump. much better clearances than the aftermarket. Lost 5 lbs with a new melling. The IH pump is built to go a million miles.

I have a line on good valves if you want good stainless. same alloy as Hi perf powerstroke.

 

[88 Ford]

Russ how does stainless steel compare to inconel as far as strength and heat resistance goes?

 

[icanfixall]

Inconel is a high heat and abrasion reisitant material. It like stainless steel on steroids. Its very hard to machine or grind too. It sure works well as an exhaust vavle. Actually the stock exhaust valves served me well for almost 300,000 miles without every giving any issues. My passenger side head never came off the block till I pulled the engine. Many years ago I cavitated number 8 cylinder. I sleeved that cylinder and the shop I had do the work would not replace the head gasket on the passenger side of the engine. I told them to do it no matter what. They said it was not warrented and a waste of money to do that... Well I'm sure they felt I would be back later asking for that side to be done when it lifted the head... Never happened... They lost a customer too over that issue. I was towing heavy and fast boosting to 12 lbs. Never lifted the head or had any head gasket issues. Thats a built stock engine from the start too. That engine saw the "check engine lite" on several times its its lifetime too. Thats 242 degrees plus hot... Now that a well built engine from the factory.

 

[88 Ford]

So pretty much inconel would be they way to go over anything I take it? That is what I figured. Thanks for the info.

 

[IDIBRONCO]

The only problem I ever heard of with the Silvolite pistons were with the snap rings. Our machine shop said that they got them from another manufacturer. They had a big run of snap rings that weren't hard enough. They would run for a while and then fall out of the piston. Then instant grenade! This was back in the middle 90's so I'm sure they haven't had any problems since. I would personally run the Mahles, but that's just my superstition from past experiences.