Thread: When are forged internals needed?

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Going by general rule of thumb, when is the upgrade to forged parts needed when building a small block? I've been f-ing around in DD2K a bit and put together a nice 383 that would redline at 6500, make 529 hp @ 6000 and 510 ft lbs @ 5000. Would you guys reccomend forged goodies or would I be safe with a cast crank, hypertuetic (sp) pistons and eagle SIR rods (Eagle rates them at 500 hp)?

over 6K Id use forged pistons personally, the rods are probably OK.
Id use a forged crank at that level, unless you use a lightweight piston/pin package

I'd put forged in anything that's going to get beat up ..... i.e. ''raced @ the track''. That's just me tho I suppose, I like to build things that can handle more abuse than I plan to give 'em.

i agree with you do it right and you dont have to do it again but geting my uncle to see it that way is not goin to happen........oh well......

Some of the most consistant answers I've ever seen here. All very good answers that You should strongly consider their advice. Rod selection is good. Think forged pistons!! Id rather have a cheap set of forge than the best set of Hyper pistons. This is more of a question to the other guys here than a statment. Have any of you had or heard of much failure problems with a stock 400 cast crank? I know of several that have been using it with no problem. I used the stock crank twice in 2 hard hitting 406s,but they were street--strip combination motors built on a budget.

A cast crank is usually fine as long as you are not going to force induction (blower/turbo) or are going to put nitrous on it....what kills a cranks is a sudden power spike or harmonics that get out of control....use a quality balancer either a TCI or Fluid dampner....those hyperutechtics will fall under the same guide lines.....if you question the rods have them "shot peened" a few more times.....

In my 341(327 stroked) I used a steel crank, already had it, and Lunati forged "lite" piston then sent them out to be lightend another 50-100 grams and I used the factory stock "small journal" rod and it's making 706hp@7800 and lives....

Originally posted by riverhorse59
Some of the most consistant answers I've ever seen here. All very good answers that You should strongly consider their advice. Rod selection is good. Think forged pistons!! Id rather have a cheap set of forge than the best set of Hyper pistons. This is more of a question to the other guys here than a statment. Have any of you had or heard of much failure problems with a stock 400 cast crank? I know of several that have been using it with no problem. I used the stock crank twice in 2 hard hitting 406s,but they were street--strip combination motors built on a budget.

Thats I can only imagine how that must sound at full song!! Ideally I would love to use all forged internals, but I'm on a pretty tight budget. I only work part time because I'm still in school so $300 to me is huge. The car would see the street more often than the track, maybe a weekend or two out of the year I'd take her to a local road course or a strip. The camshaft I was thinking about using was one of those Comp Cams that swaps cylinder 4 and 7 in the firing order. Comp says by doing this it helps to relieve some stress on the crank in addition to making a little more hp.

hotrod did the same test and had the same results for both...so I wouldn't bet a paycheck on it....If your on a budget....use budget stuff.....

Of course, you could build that same engine using a Gen III iron block from a 6.0L V-8 (LQ4 or LQ9) with a light overbore. The lower ends are pretty much bullet proof. If you don't want to use EFI, GMPP sells a carbureted intake manifold with an ignition controller. They also use aluminum heads and with LS6 heads with have a CR over 11:1. And you can use the stock lower end.

These engines will twist to 6500 real easy and they even like high lift cams without causing drivability issues. You might want to check these out.

If you're on a budget and 300 bucks is a lot, how did you manage to throw together a 383 that makes over 500 horse and 500 ft/lbs? I am in the research stage of building a similar engine, and have thought NOTHING of going with anything but a forged bottom end, but I'm looking at a large chunk of change... may I ask what setup you're going to be using?

I haven't added up the costs of any parts yet but it's looking like its going to be right around the total of the HOT ROD Magazine 383 build up in March of this year. They did it for around 6 grand. I believe they said they opted for forged internals because it was borderline. I just wanted some more opinions. I know forged internals would be the best buy if I don't need them then I could put that money towards the transmission or something else.