antzahh

Hello fellow Oldies!
I'm new here so Hello everyone!
I've been working on '72 350 (.030") over block with flat top pistons (Speed pro) and stock rods, crank, girdle for main caps and rotation assembly is fully balanced.
I got some goodies for it like 7a iron head (on the machine shop) Victor intake (same), Comps cam with solid lifter (can't remember the specs but its matched with flow capacity of the heads and intake), 750 dp ultra holley, steelies, delco HEI Ignition with pertronix adjustable rev limiter, th200r4 (beefier), 4:10 gear.

The Intake and heads have been ported, head's flow capacity is like 510hp but we are aiming for 450ish hp. 1.995"/1.710" valves, 3-angle job, bigger studs for roller PRW rockers, guide plates, bigger pushrod holes and other little tricks.
Compression is going to be around 11:1. And the machinist said that the rev limiter should be at like 7000 rpm while the engine makes the most power at 6000-6500? So im asking that is this old lady capable of this all punishment?

And YES, I AM aware of the fact that the Victor is not maybe the best option for the street/weekend drag type of vehicle but damn that thing looks cool and i wanna do something a little different.

Jeff Stout

Should not be a problem. I run mine at finish line rpm at about 6500. Been 7000 with wrong rear gear. Nothing fancy using stock internals

olds 307 and 403

What are you running for a converter? Also what duration of cam are planning on and what octane of fuel? Copper on here has pushed similar revs with a similar combo, so it is possible.

antzahh

I Appreciate!

antzahh

Machinist told that i need 10" instead of 12". And about 3500-4000 stall. Can't remember the duration and it's 98-99 octane.

antzahh

And one thing that's for sure, i would like no know that is it MUST to add oil-restrictors? I mean in those rpm's. Other's say no and other's absolutely!

olds 307 and 403

Most builders say it is a waste of time to use restricted, just BS. How many bottom end failures does an Olds 350 have? Very few compared to the larger journal and heavy parts 455's. Your converter sounds good along with 4.10 gears. Do you know what your heads flow? I assume some stiff valve springs along with a lot of duration on the cam is being used.

joe_padavano

More to the point, take a good look at the oiling system routing in an Olds motor and then tell me how those cam bearing oil restrictors do anything to limit oil to the rockers.

antzahh

Nosto = Lift
Vakio = Stock
Portattu = Ported
Imu = Intake
Pako = Exhaust

olds 307 and 403

Those numbers look really good. What was done to get such high exhaust numbers?

VORTECPRO

Good question............

antzahh

I dont know man, magic maybe? I think that the guy is talented! Exhaust valve is also big, 1.72"

fleming442

Make sure the piston to bore is .004-.005 and you're golden.

SEND
IT!

coppercutlass

I regularly hit 7k Ported heads but no flow numbers. 10.25 to 1 compression 93 octane. 4500 stall and 3.90's. bread and butter stuff nothing fancy. I don't have a girdle or anything like that just ARP bolts .

Inline

Who did your heads?

antzahh

Pro Street Ky here in Finland

antzahh

I think 10" and the cam is comp cams 42-655-5. Premium pump gas.

olds 307 and 403

With that solid lifter cam, I can see why you are thinking of a Victor intake.

antzahh

antzahh

One thing is bugging me right now because the engine assembly is really close and the crankshaft, well is not original. It's from rockauto and it was sold by the name of "remanufactured crankshaft" and i've been reading a couple things here and there and also one guy came up to me with dm and told his story about destroying his own engine which was 409 olds and destruction was caused because of poor quality crankshaft, he mentioned about some kind of "weight reduction" holes in both end of the shaft, checked mine and yep i have those too, so i was just wondering that is the crank be able to handle those massive 450ish hp?!
Do you guys have any tips or maybe own experience about crankshafts..? THANKS.

antzahh

One thing i now found out that the crank is from 1977.

olds 307 and 403

Does the front throw on the crank have almost a beveled machined edge on the throw? I also find them a lighter grey in colour. The 73-75 cranks look different colour wise, have the big front throw but no big "N". Their strength, who knows? Yeah, your power level and rpm with heavier pistons may be an issue. Unfortunately finding a forged crank is near impossible where you are and expensive to have brought to Finland.

antzahh

Well i did more research and found something weird.. the old crank had 393654 code on it "68-74 Cast nodular iron" and now my new one got 556607 code on it "307 V8 81-90 Cast nodular iron"
Im confused..

66SportCoupe

Because all small blocks had the same stroke and bearing sizes (except diesels) all cranks interchange. That later crank is NOT of the strength of the early one. I personally would not not use it in a really high performance build.

oddball

The 330 forged crank is the best OE small block crank, but shipping would be expensive. After that, the earlier cranks are "supposedly" stronger than later cranks, but there's a lot of myth and suspicion about metallurgy over those decades. It's hard to tell if any of that is real. IMO, worrying about crank strength is more related to how much power you'll be making. Do you have a specific goal?
The bottom end is not especially strong on the Olds. Make sure you're using an earlier block with solid main webs - not the late blocks with windows. So the key is keeping the rotating weight as low as possible. Using lighter rods, especially using lightened pistons, is a good idea. Weight will cause problems at high RPM, and the stock rods and stock-style pistons are quite heavy.
Beyond that it's basic stuff - make sure the valve springs are up to the task, use a large sump oil pan. I would also use restricted pushrods - either 5/16 thick wall, or 3/8 restricted. That's much more useful at limiting unnecessary oil to the rockers, where there can be too much flow. The "oil restrictors" that are sold just limit flow to the cam bearings, which is not particularly useful. You can get the same effect by drilling smaller holes in the cam bearings. But, you'll probably be running high spring pressures, so limiting oil to the cam bearings might be a bad idea.

antzahh

I own a parts engine from '72 i believe and i took the oilpan and there's a crank in with letter N on the front and 393554 numbers.

Horsepower goal is about 450hp.. the assembly is fully balanced.. (damper, flexplate etc.)
The block is earlier, not the windowed type.
I already have 7qrt pan and sump for that.

fleming442

That sucks that everything is already balanced to the "new" crank. I'd drop back and punt: get the old (or, an older) crank turned, then rebalance. The damper and flexplate weights shouldn't change.

Also, as been said, lighter is better. Here's your chance to sell the whole balanced assembly and lighten up the pistons and rods for that 7000 rpm life.

antzahh

Yep but i think that the guy who rebalanced my setup in his shop didn't touch the crank itself at all.. the crank was off like 25 grams on the front and 60 grams on the back and i think that all he did he grind some weight out from flexplate and some from the harmonic balancer.. atleast i dont see any marks of grinding on the crank..

Inline

Chances to sell anything Oldsmobile-related performance parts at Finland is near zero.

antzahh

Ye here is the thing called "verkon paino"

fleming442

I wouldn't call that rotating assembly "performance" in any part of the world in relation to what you are trying to accomplish. As far as I know, shops here in the States only add or remove material on the counterweights during balancing. Then, if something goes south, you can at least reuse the end parts on a stock engine if desired. It's too late now, but something to consider in the future. Good luck!

antzahh

But isn't that the only way to rebalance your assembly if the engine is externally balanced?! Only cut/add from outside weights such as damper and flexplate?! There's maybe something i dont get.. It wouldn't be the first time..

66SportCoupe

I would take the older N crank flexplate and balancer and have them balanced to your assembly. Sell the other parts.

antzahh

Yeah something like that..

olds 307 and 403

Good plan on the N crank. Internal balancing is best and usually the most expensive. If for example your harmonic balancer goes south, any replacement should work. On an external balance engine, the balancer and flex plate must be the same weight if replaced. Good part about those heavy Speedpro forged pistons is similar weight to stock pistons, probably heavier if anything. They will probably have to remove weight instead of adding expensive Mallory metal.

antzahh

Yep thats what he did in this case, removed weight. And these engines are externally balanced from the factory, right? Shop guy mentioned too that the Mallory is really expensive..

fleming442

Yes, Mallory slugs are ridiculously expensive, and that's why I don't have a 496. The 4.5" Eagle crank needed too much Mallory to internal balance.
You can balance internally or externally without messing with the fexplate or damper. Depending on which way you go determines what you buy. Stock stuff is externally balanced and has offset weight built in. Neutral balance dampers and flywheels or flexplates are just that- neutral. My 468 is an internally balanced, offset 425 crank with a neutral balance ATI damper and custom Science Friction (American Powertrain?) flywheel. Balancing shouldn't affect the end pieces; they dictate how it's done, though.

antzahh

Now that makes kinda sense to me!

olds 307 and 403

That sounds good, yeah I forgot about those pieces in aftermarket form, flex plate especially. Mark was telling me my offset ground 330 crank will probably need 4 slugs, yikes.

antzahh

And that sounds expensive..