Hello fellow Chevy fans

I was wondering if the pistons,crankshaft(cast), 5.7in connecting rods wil be able to handle 400hp set up? out of a 305 block, it has been rebuilt 1500kms ago but was a pisspoor job and now redoing the task myself and sence it is in pieces before me. Now would be the ideal time to swap stuff out, for my goal hp

Best Regards
Skoda

 

Short term, yea it would probably hold up.

I wouldnt plan on using it for a dialy driver, it would pretty much be a ticking timebomb.

 

So I'am geussing forged pistons and crankshaft are the way to go?

 

Yes, a forged bottom end and ARP bolts all around (including main caps) and i wouldnt worry one bit about it.

But like anyone else will say, if your going to spend the money you may as well spend it on a 350. A 350 is alot easier to get 400hp out of! A 350 running cast parts isnt too bad @ 400hp, still a bit for a stock bottom end but as long as you dont spin it to the moon it should last.

 

I sure this will hold up right http://store.summitracing.com/partde...5&autoview=sku

For the crankshafts I havent found any possible fenders that are forged that seem reasonable in price 300-600cdn

The stock connecting rods will be able to take the pounding?

Thanks for the help
Skoda

 

423 Flywheel Horsepower @ 6,500 RPM. I have not had the engine in a car yet with this combo, but I bet it would do low 12s in a 3rd gen with traction.

Block = 1983 4-Bolt main 305 (14010203 casting), Bored .040" over, Torque plate honed, Decked .025", ARP Main Studs, Align Bored

Crank = Stock GM Forged Steel (3941188), Lightened, Smoothed, Knive Edged, etc for less windage, balanced with the entire rotating assembly

Bearings = Federal Mogul Speed Pro Coated

Rods = X casting rods, Parting lines ground down, Lightened, Balanced, Shot Peened, Weights Matched, ARP Wave Loc 3/8 Rod Bolts, Reconditioned

Pistons = Stock L69 Hypereutetic Replacements, Flattops with 4 valve reliefs, -6 cc, 0.00" in the hole

Rings - Total Seal Gapless rings

Compression = 10.7:1 with 54cc heads, Zero Decked block, .038" compressed head gasket.

Heads - Ported 2004 ZZ4 castings ("463"s), cleaned up in my garage, final "MAX EFFORT" port work performed by my buddy in his machine shop, .100" longer valves than stock (1.94/1.55 Under Cut Stems, Swirl polished), 5 angle valve job, Forget the exact spring but they are meant for the cam and .100" longer than stock valves, .600 lift compatible. I had to use longer than stock push rods as well. Machined heads for Comp Cams guide plates after opening up pushrod holes in heads. Gasket matched to a Felpro 1206 (1.34" x 2.21")

Head flow @ 28 in/h20 with a 3.75" bore simulator (engine has 3.776" bore).
Lift------Intake---Exhaust
.100------57-------57
.200------123------118
.300------177------162
.400------223------183
.500------229------188
.600------238------193

Camshaft = Comp retrofit roller XFI280-H13 (280/288 @ .006, 230/233 @ .050, .576/.570" lift with 1.6:1 rocker, 113 LSA, 106 ICL) Cloyes Double roller timing set

Intake Manifold = Holley Projection TBI for "OLD" style heads with the same bolt angle. This intake is a dual plane, high rise, with 2" bores. Gasket matched to the Felpro 1206 intake gasket

TBI = TBI unit off of a Heavy Duty 7.0 liter TBI truck, 68# injectors at 32 PSI, 2" bores, thinned throttle shafts, radiused the entrance to the bores, sitting on a 1" tall open center TBI spacer, 720 CFM @ 3.00 in/hg

Headers/Exhaust = Hooker Super Comp 1 3/4" x 3.5" meant for a mid 70s Camaro with a 350. 3" duals with X-pipe (not used on dyno)

Ignition = Stock GM HEI EST small cap distributer (computer controlled) with MSD coil, MSD Module, Moroso Ultra 40 wires, AC Delco Rapidfires @ .045"

Oil System = Moroso Blue Printed Oil Pump w/ Pickup, Moroso Steel Shaft, Moroso 5 quart pan, Moroso Oil Control Kit, Mobil 1 5w20, 70 PSI Z/28 spring

Crankcase Evac = LT1 style Electric AIR pump pulling a crankcase vacuum of about 6 in/hg.

ECM = RBob's EBL with lots of tuning. 34* total advance @ 2,800 rpm.

Dyno Numbers (all rounded to the nearest whole number for simplicity)

RPM------HP----TQ
2,400----147----323
2,600----166----336
2,800----185----347
3,000----207----362
3,200----223----365
3,400----238----368
3,600----263----384
3,800----281----388
4,000----301----395
4,200----322----403
4,400----347----414
4,600----363----414
4,800----378----413
5,000----382----401
5,200----393----397
5,400----401----390
5,600----410----385
5,800----417----378
6,000----421----369
6,200----422----357
6,400----423----347
6,600----419----333

That is 423 FWHP @ 6,500 and 415 ft/lbs @ 4,500.

 

I wouldn't pay $40 a piston for pistons going into a 305. I'd get the cheaper hyper pistons ($9 per) and put them in a 350. Rev it less, get same power, higher HP ceiling for later down the road, etc etc.

 

Absolutely.

As in, swap out that 3.736" bore casting of a block. Swap in a 4.000" bore casting block with appropriate pistons, rod bolts, machine work, rebuild parts.

If you insist on trying to get 400 HP out of a 305, the pistons and crank are fine. If doing a clean-up overbore, the aforementioned hyper pistons would be a good idea ($25ea less than the forged). The rods are a different matter. They need upgraded bolts and precision resizing. Shot peening isn't a bad idea, either.

 

I want my 305 to be completely finished. I try not to down on any V8....not even Fords 3.4l V8 in the 99 Taurus SHO. LMAO. Yeah a funny V8 but still a V8. I have the same plan as him and thats building a badass 305. I dont have many to buy a 350 and then start building so I am sticking with my 305 until it is finished or close to what I want. I am looking to have the license plate

350 KLR

Just kidding....but it wouldnt be bad if you had a 305 and wanted to kill 350's with it.

My goal is 527hp.....or 527tq whichever comes first. I know I cant get that type of power out of an LO3 305 but hey Im going to try and get every last bit of power out of this motor.....before I buy a 350....unless I can find a 350 for cheap that has low miles like under 30k or buy a new 350 with 0 miles and baby it for 3k then MASH it on the first person who pulls up 2 me.

 

500+ hp from a 305? Now that's pushin it.

 

No I said I would like that.....its my goal but I know I cant get that from a 305 without....a little buddy......N2O....but I dont want to put that into my car....as of yet

 

that 423fwhp will get you somewhere around high 12's low 13's.. not much torque in your mix..

 

Did you not happen to notice that it pulled 320 ft/lbs as early as 2,400 rpm. By 2,800 it is out torquing a Stock L98 350 TPI engine. Peak torque was 415 ft/lbs @ 4,500 rpm.

My Fullsize Van (5,300#) ran 14.8 @ 96 with a 2.18s 60' with the previous version of this engine. With ported 081s and a smaller cam it pulled 301 RWHP. The Van had P295/50/R17s, 4L60E with a 2,800 rpm 10" lockup style converter, and 14 bolt rear with 3.73 gears with an Eaton Differential

 

That HP number NA would require spinning that poor thing to the moon - you're talking nothing but high-dollar parts to get there.

The torque # will not come out of a 305 NA - no way, no how.

Whatever you do, you have to stay within the bounds of physics. Some laws can't be broken.

 

i've got a calculated 443fwhp from a daily driven n/a pump gas 305 and has been 12.31@108mph and i'm still playing with the tune. it's possible.

 

The original question was 400 HP on stock cast parts. Matt, you ain't runnin' stock cast parts.

The "famous" 400 HP 305 magazine article did it on a stock shortblock. Until they grenaded it on the dyno at that power level (don't hear much about that).

And F355, you've done a lot of the "right stuff" to your shortblock as well. Key item: ARP rod bolts (not to mention the rest of the rod work).

The highjack question targeted 500+ ft-lb torque NA. That ain't gonna happen. F355's dyno #'s show 400+ ft-lb NA - impressive, and your #'s will probably be close, Matt, but that's still 25% short of the out-of-the-air # from Mr. HJ.

Reality, people. That's all we ask.

And I still agree with the originator's statement: "Now would be the ideal time to swap stuff out, for my goal hp".

And the least expensive, and arguably most reliable thing to swap out to get there?

The 305 block!

(You don't have to have been around very long to know I'm not a "305 hater". You should also know from very little time here that I prefer to spend the least amount of money to get to a desired goal. "Different" just ain't good 'nuf of a reason.)

 

i agree whole heartedly with you five7kid, i was just sayting it's possible. and no, i'm no longer running a stock rotating assembly, and forged parts are coming, to replace these ones!

if you want 500ftlbs and you want it cheap and streetable, cubic inches are your friend. while you may think you don't have the money for a new block, you're very mistaken, because even though they are hard to locate, they are truely only like $200 or less. shoot, i've got a 4bolt .060" over 350 block ready to rock and roll right now for sale for $150!

 

I also have to agree. Drop a 3.875" stroke crank in a 1 piece rear seal 350 block and have fun.

You can put over 500 ft/lbs to the crank at 3,500 rpm.

 

What I wanted to hear bare with me please through the parts that will survive, list:

Crank
Connecting Rods(with some mod/ new bolts)
-What do you mean by "precision resizing"? that they are blalanced?

For the shot peening process, I'd go to a lacal manching shop for this?

Why keep the 305 your asking... Well sort of a under under dog story, bascily it came out of my dads IROC vert sence he's had nothing but bad results with the engine he said #uck it and now it rest's in my hands with a 1000 dollar bet in the balance that I wont get it working right

 

What happened?

 

precision resizing - when you put on new rod bolts (ARP say), it changes how much it clamps, so you need to resize it. They tighten the new bolts in place, then hone it to the correct size. Once you pay for new ARP rod bolts (say $80), resize ($80), and shot peen ($80), you really wonder why you didn't buy new rods that come with ARP rod bolts, say Ohio crankshaft's $160 specials. That's what I did, and mwNova66 I think.
Those prices for the reworking the stock rods are just #'s out of the air, but you get the idea, it's no exaggeration to say it's CHEAPER to buy new ones, then rework your old ones. There is very little reason to rework your current ones, unless you get a smokin' deal on the rod bolts, and have the machining equipment in your garage (I doubt you do, so...)