Sebski

Ive been looking around just researching some forged internals. When they refer to pistons and say either 5cc or up to 23 cc what does that refer to. I dont think it has anything do do with compression ratios but then i dont know... that is my question?

Also in rebuilding an engine for blower nitrous application is a new bottom end necessary or simply forged internals i.e rotatiing assembly, heads, valve springs and cams... Does the short block need ot be replaced or what... to me that would be like haveing a comepletely new engine.

2000GT4.6

The cc refers to the dish of the piston. The more dish the less compression that particular piston will run.

I have been told that there is alot to putting a shortblock together, much more than just buying some ARP fasteners and the rotating assembly. However, I have seen no proof of this. I would think so long as you have the TQ specs for the fastners a seasoned mechanic should be able to do it.

myshifter

I hear forged internals here alot. The only thing forged is the piston, the crank is cast steel and so are the rods. As to the cc question, yes it has everything to do with compression ratios. As far as building a performance motor, a seasoned johnny fix all mechanic is not the guy you want to use. For instance you just got the bare block back from the machine shop, its all clean and shiny looking, looks great, but suppose the guy boring and honing the cylinders was asleep at the wheel that day and one cylinder is a couple thousandth shy at the taper point of the cylinder. Your regular mechanic goes to put it all together but he surely doesnt have bore gauges to check all the cylinder bores. So you put it together and low and behold you go through all the work to put this motor together and it breaks a piston ring in half cause the machinist was lacking in his quality that particular day he bored and honed your block. theres a reason why an engine builder has 10,000 dollars worth or hand tools in his box.

Sebski

So essentially buyin a new short block is not necessary when wanting to rebuild and engine/ Simply head and cam swap, Rotating assembly, and a PI intake?

blackbetty01

Thats a great start, it really depends on your final destination. The stock block can easily handle 600hp with a forged rotating assembly. I have heard of alot of people saying not to get a forged crank, just a steel one because it is an easy way to shave weight and a forged crank is an overkill. Good Luck.

Sebski

Do you think the stock block can handle 10-12 psi of intercooled boost and a 100 shot of nitrous?

blackbetty01

I would say yes, I have a buddy with a forged 331 stroker kit and a Vortech T trim S/C running 15 psi of boost on a stock block. Thats probably about the same HP you would get from 10-12psi with a 100 shot.

06mustang88

no, stay between 8-10. you can run 10 (i'm not sure with nitro) as long as you have a good tune with it

Sebski

U sure dude, forged rotating assembly, new heads, cams, and PI intake not 10 - 12 with a shot a giggle every now and then.. Peps have said the stick short block can hold arround 600HP is that true? But then i dunno hence im asking

blackbetty01

I think you are definitely talking about stock internals buddy.
Forged internals will have ZERO problems handling 10 psi of boost. Hell ask racer02stang, I think he is running 10psi on STOCK internals. Thats just crazy in my opinion.