[cobalt327]

Originally Posted by Horsepoweraddiction

i'm going mechanical roller and would i get more performance with a set of forged pistons ? i 'might' run a small nitrous set up.

Generally forged are heavier and run a looser piston-to-wall clearance. But there are lightweight (or lighter weight) forgings that run tighter clearances than some of the old style forged pistons.

But there's little if any difference in the actual performance between the two if they are both set up properly- at least until the cast/cast hypereutectic piston reaches the point of no return, a point which will be found sooner than a forged piston. Just be sure to fully warm the engine up before hammering on it w/forged pistons. That gives them time to expand closer to their running dimensions where the ring seal will be better because of less piston rocking.

But if you plan on nitrous, forged gives a lot more leeway in case of detonation. Detonation can kill ANY piston when running nitrous, but a cast hypereutectic piston will literally shatter whereas a forging will tend to go down in one piece for the most part unless the detonation is ignored. And it may even survive if the detonation isn't that severe.

Nitrous is very demanding on an engine. Aftermarket rods might be in order because I do not know of anyone who has been satisfied w/a "small" shot of N2O. At the VERY least, the rods need to be magnetic particle inspected, new ARP hardware installed, and then resize them. There are ignition boxes that will pull out timing to keep the engine safe; if I were to build a serious nitrous engine, you can bet I would be running one. Not really necessary at the lower levels, but even then the timing can be run higher when not using nitrous- which equates to better performance when on or off the bottle.

When you get to the >250 HP stage, think about better rings/ring material. Even at low doses, plasma moly is the minimum because moly inlay can chip off the ring. 250 HP and up forged isn't an option IMO, although you'll hear guys who get away w/it. Trouble is there's NO leeway if the tuneup is off, or a fuel pump problem comes up or for any number of things.

This barely scratches the surface but will give you some things to think about. There are guys here w/more experience using nitrous than me, hopefully they will be along shortly.

[632Mantis]

Originally Posted by Horsepoweraddiction

i'm going mechanical roller and would i get more performance with a set of forged pistons ? i 'might' run a small nitrous set up.

Mech roller: Woah! There's a jump in price. You building a high-RPM race motor now?

You don't get "more performance" from forged pistons. You buy forged pistons because they can take more punishment and survive.

Nitrous rules. Cheap HP. Make sure you have a good fuel system. Run a plate kit. I would run a fuel pressure gauge you can SEE while you are driving. You lose fuel pressure on the spray, and you can do engine damage. Watch your ignition timing. Rule is back off 2deg per 50HP over 100hp on the nitrous kit. Colder plug above 150hp kit. I would actually recommend between 100hp-150hp. No more. Thats a good safe range. You can run a bone stock motor on a 100-shot.

I would forget the mechanical roller setup. Way too expensive for a street/strip motor. That Xe274 cam you had picked out is actually awesome. I run the next size up in that line. Very happy with it.
You plan on twisting that big motor past 6,500 rpms? If not, run the oval port heads, 9.5 compression, the 274 hydraulic cam, 1.7 roller rockers, Edelbrock Performer RPM AirGap intake, headers + dual exhaust, MSD 6AL box, 3:89 - 4:11 gears, a 3,000 stall converter, the N2O plate kit, some cheater slicks, and be happy.

The only reason to go roller cam, and big aluminum heads is if you are running a big-inch stroker motor, 14:1 compression race gas, high-RPM 7,000+.
If you want to keep it "streetable", run that setup I recommended.
Save money. Have fun.

[Horsepoweraddiction]

Wiseco it is then! i am also having the rods reconditioned like i was supposed to. 550hp is my goal.

[632Mantis]

Originally Posted by cobalt327

Nitrous is very demanding on an engine. Aftermarket rods might be in order because I do not know of anyone who has been satisfied w/a "small" shot of N2O.
When you get to the >250 HP stage....

I am very satisfied with the 150-shot plate kit I have on my BBC motor.
I'm not even considering going with 250 or more.
My motor could easily handle a 250 shot, but I would need to upgrade my fuel system to be safe. I don't really care to do that.

I have no goal or reason to try and go faster. My truck is super strong just the way it is. I have fun with it. That's all I need.
There comes a point when you just get tired of spending money and working on it all the time. I'd rather just drive it and have fun. It is what it is. I have satisfaction in building it myself. I don't have to be the "fastest" in order to have pride in my work.

[632Mantis]

Originally Posted by Horsepoweraddiction

550hp is my goal.

Don't be so focused on a certain peak HP number.

Trust me, you will be happier with a strong torque engine that pulls hard from down low through the midrange. That is what you "feel" when you nail it.

Throttle-response and torque gets you rolling.

I would rather have a Big Block that makes 500 torque at 3800 RPM and 480hp at 6,000 than one that makes 200 torque at 3,500 RPM and 520hp at 6,500.

You just pick your tire size and rear-end gears to match the torque curve, and you are all set to rock. You don't have to run as much converter stall either. It's a win-win deal.

[Horsepoweraddiction]

Man you are right and nitrous would do what i needed it to do at times. but i own 3 454s and they need building haha. but for the one currently in my truck i am satisfied with it 'for now' but i will build me one with mech roller and so on and so forth. i'll further gather my knowledge and see what i come up with man. Thanks for commenting man. i got this 496 i been wanting to build haha.

[vinniekq2]

did I hear 540?

[632Mantis]

Originally Posted by Horsepoweraddiction

i got this 496 i been wanting to build haha.

Hehehe..... that's exactly what I did with my 454.

Stroker crank, long rods. Had to clearance the block some.
Was seriously worth it. It's a stump-puller.

[632Mantis]

Originally Posted by vinniekq2

did I hear 540?

LOVE the 540. Love the 632 even more.
But now you are in the world of big-money. Can't get 540 cubes from a stock 454 block.

And with that many cubes, big port aluminum heads are a must.

Only problem with running bigger than a 502 on the street is the darn things drink GAS! I love big-inch motors, but you can't drive past a gas station.

Gotsta keep it "streetable".
I doubt I could get a 632 to hook up on the street anyway.
( Funny car slicks with some grooves cut in them? )

[vinniekq2]

The 540 option is like the 434 option in small blocks,the price is decent,you dont have to use a tall deck like the 632, street able 675 hp 540s are common and can put any car deep into the 11s. all with a single 850 and hydraulic cam.
Gas mileage is figured by sfc and gearing/average speed,,,,,,etc. Gas consumption will start at lots and go upwards

[cdminter59]

Horsepoweraddiction, You say you have (3) 454 motors. For now build a mild streetable 454 for your truck. Take a block, crank, rod & pistons, and your 781 heads to the machine shop. Have the machinist check the block, then have it dipped, bored & honed, install new cam bearings, freeze plugs, screw-in oil gallery plugs, and deck the block. Have the crank checked, if ok have it polished. Have the pistons removed from rods, install Arp rod bolts and then have rods resized. Purchase Keith Black Icon Forged Pistons part# IC779 at CNC Motorsports for $510.95, Jegs $649.99, Summit Racing $719.95 and have them installed on rods. Have your heads checked out and don't forget to have the matching springs for your XE274H-10 camshaft installed. With a build like this it will be strong enough for the 100-150 shot of nitrous to get you to 550hp.

[Horsepoweraddiction]

Wow those pistons are that much cheaper at CNC motorsports? And yeah I'll probably do something like that. Seems to be the best route until I build that 496 haha. I'll be building that race motor then boys.