I've built some aggessive little (96-105 CID making 120-150hp) motors based around hypereutectic pistons and never had an issue, so I'd say I've had good luck with them. I also tend to be pretty good about building to the power level I actually want.

Seeing as how this is going to be a tow rig/daily driver I'm building for as much torque and as flat of a band as I can with the side effect being I should kick out just under 400hp. There won't really be any room to add power without making the powerband unuseable or using power adders which is NOT where this motor is going.

Justin

 

Well with that said.... I think I read you said that the Hypers have gone up $140 a set? How does that compare in price to the Forged Speed/Pros/ TRW's...

And I'am sure , being how your an engine builder...that when towing uphill you seem to be prone to detonation.....and also on flat ground depending on the gas being burned... JMO...

RJ

 

I wouldn't go quite so far as to call myself an engine builder, just someone that has built his share of engines.

Yes, i realize that motors are more prone to detonation while hauling, running hot, running excess compression, or too low of a quality of fuel. That's where matching all of the components comes into play and that's why i'm not rushing this build.

About all I know right now is I'm staying at 390 CID+ whatever overbore it takes and staying right about 9.5:1 compression. Other than that I'm doing my homework to make sure this thing turns out right like i need it to.

As for the cost, the forged pistons are a little more than twice as much, but it was said the factory isn't producing them right now. Since I don't have the budget to go out and buy a set of forged pistons right now, i might *have* to build around hypereutectic pistons as the next set of forged pistons for a 390 costs about $550 which is definitely out of the picture.

I'm also currently running a set of hypereutectic pistons in my 9:1 300 that has seen it's fair share or tow duty, running hot, and bad gas on a much milder cam than I'd be running in the 390 and they have yet to have an issue.

I think it all comes down to what the intended use of the vehicle is. I'm not building a race truck and it's never going to see any power adder. Forged pistons are nice, but i don't see them as being necessary for my build.

I was originally intending on using them just to get the compression and quench where i wanted it to be, which the 1131h's will do just as well.

Justin

 

What about Probe pistons? They are forged, light, and pretty reasonable. They are $436 for a 4cc flat top and $457 for a 16.9cc dish. You can also find some nice used sets of forged too from time to time.

 

I just sold the 1131's I had on ebay, I was wondering if hoxii was the buyer ? They went for my "buy it now" price of $95. $130 with the shipping & handling

 

You can still get teh Speed-Pros for a bit over $300/set - - its just that when they run out - they'll be out for a loooong time.

 

And I don't have a little over $300 immediately available, that's why i'm seriously looking at other alternatives since I don't know when I'm going to begin collecting parts for the build.

And i wasn't the buyer on those pistons. I'm not buying anything until i know exactly what this build is going to consist of top to bottom.

Justin

 

HERE HERE I agree,, I am useing KB hypereutectic with a set of iron 73 cc heads. 0.00 deck mesured after build, wow works grest. must use 92 oct + but wow it runs great, and the design of the pistion with a 20 cc step dose work to give you a very deffent point in the timming curve that ping will happen, and will stop. I have used TRW forged, and the KB plugs deffently run out better on the street, they do not seem to need the copmressionm to get the same hp. just watch the clearnces and your top ring gap....... dont forget drive it like you stole it