Strongest block? SBC/SBF/LS??

[Caveman]

Okay... regardless of allegiance here...

What stock SMALL block would be strongest? What would take the most abuse, rpm, and the most spray? 302? 351C? 351W? 350? 400? Iron LSx Gen III? Mopar?

Assuming an iron block, what would hold up? This is aimed at us low-buck dudes who can't go out and buy a little M... so where to start looking in the junkyard?

I heard David Vizard did a test on a stock SBC, and sprayed it and sprayed it on a dyno until something broke... supposedly, the block cracked at 1000hp. True or false?

[Brian Lohnes]

Re: Strongest block? SBC/SBF/LS??

302's start sawing themselves in half in the 4-500hp area so they are out.

Brian

[Caddyman]

Re: Strongest block? SBC/SBF/LS??

1. LS iron block. Over 1300+bhp using aftermarket crank, over 1000bhp with stock cranks. Just rods/pistons/good MLS gaskets. Basically, the LS engine is making everything else, obsolete overnight.

Its kinda hard to imagine "conventional" SBC's are, in reality, going the way of the flat-head Ford.

2. SBC 010's, aftermarket caps, will go over/at 1000 Bhp with a half-fill. This is a 2-bolt to 4-bolt conversion using good billet splayed caps, a GOOD forged crank/h-beam rods. The most important things? Don't detonate it, and keep the rpm lower. If using NOS, make sure to use a progressive or staged system. If boosted, make absolutely sure to have good boost controls and proper wastegating.

3&4. 509 "400's" SBC's are only good to around 800 (factory 2-bolts, 4-bolts lower) or about the same as 351 based Fords. Both good to around 850 with upgrades (caps, filled).

And yes, 302's are great till about 490-525bhp. Some live to 600 (consertative tune, good NOS controller or boost controller, lower rpm)...but most die at 550.

[fahrenschnell]

Re: Strongest block? SBC/SBF/LS??

I agree with Caddyman.....Iron 6.0L engines have made 900+ on stock internals....with 6 bolt mains it is hard to beat....not to mention the heads flow like crazy...

Seth

[Eric68]

Re: Strongest block? SBC/SBF/LS??

I've got a 350 block (the Goodwrench 4 bolt replacement one) that is living in a 377 (std bore, 3.75 stroke) combo with a ProCharger F1R that put down 801 HP to the rear wheels last week. I wouldn't recommend that anyone EVER try that with a stock block, but to my surprise it seems to be holding up just fine.

The LS motor would take more -- better, stronger design.

The 302 is known to be weaker than the Chev 350 010 block.

Don't know about the 351W or 351C Ford stuff.

[DanStokes]

Re: Strongest block? SBC/SBF/LS??

SB Mopars are tough little devils, but the heads suck. With the new aluminum heads, one of these might be a viable choice. I haven't seem any "spray it 'till it dies" info on them.

Dan

[dieselgeek]

Re: Strongest block? SBC/SBF/LS??

I've had a few stock 302 blocks live in the 550-600fwhp range for quite some time, but if you detonate them just once under that kind of power - they split right down the middle. The tune has to be in check.

I've tuned one turbocharged 383 Windsor Ford block (351 stroker) that made about 1100fwhp but after a season it was doing strange things so the owner went with a Dart block and stepped it up to 1800hp.


I've done a ton of LS stock block engines in the 900-1200hp range. I can only think of one that ever had bottom end problems, the issue when you hit 1200-1300hp is not being able to keep the heads sealed up tight. Parish's truck could do 1000whp (dynojet) all week long, but turn it up another 20hp (or let the weather creep up on you and give you another 20hp) and it would lift the heads. We *did* finally crack a water jacket on a stock block of his once, but we are not sure if that was from making so much power for so long on that combo (it went MANY street miles), or from an earlier nitrous mishap (that's what I believe)


I've been dying to tune an LS motor with an aftermarket block, (hint hint to any of you out there that need help putting together a 2000+hp LSx engine!!)

-scott

[dieselgeek]

Re: Strongest block? SBC/SBF/LS??

So I just noticed that you are asking "smallblock"


Do you consider a 4-cylinder GM Ecotec to be a "stock block" and part of your consideration? I've seen a handful of them in the 1200-1400hp range all running stock blocks. Stock cranks to 900-1000hp too.

Just in case you were daring to be different!

[milner351]

Re: Strongest block? SBC/SBF/LS??

Prostock guys like Glidden got pretty fancey lopping off the exhaust side of 351c4v heads and making lots of power with them using the stock boss351 block and good pistons / rods / forged crank - but I can't say I know the HP numbers.

Stock FE fords are also capable of high HP with good heads.

What I'd really like to see (or do myself one day) is a turbo EFI'd 300 ford truck six - with a cross flow head - like some of the guys run in dragsters -- inlines are inherently stronger than V's for a multitude of reasons - and at 300 cubes stock - that engine screams potential to me - but, I'm wierd like that - I've pencilled a few sketches of an A sedan with the front stretched enough to fit one of those in there.....

[Robert1320]

Re: Strongest block? SBC/SBF/LS??

No one brought up the Ford Mod motor.
Those thing will take over 1k easy.
The LSx 6.0 Iron block will but should have steel caps to live.

[dieselgeek]

Re: Strongest block? SBC/SBF/LS??

No one brought up the Ford Mod motor.
Those thing will take over 1k easy.

Excellent point, I can't believe I missed that too.


What would make this a more interesting discussion, is to talk about what these engines can do on stock rotating assemblies...

[milner351]

Re: Strongest block? SBC/SBF/LS??

I'm sort of disappointed that nobody has gone gonzo with the Ford or Chrysler V10 - am I missing something that these big mills lack?

I'm a traditional pushrod guy for the most part - so that's not my bag, but - I'd have thought with all those cubes to start with - and lighter pistons compared to the big bore old V8s - that they would have caught on more.

[Caveman]

Re: Strongest block? SBC/SBF/LS??

Hhhhhmmmm..... Mod motors...

Hmm, Ecotec... hadn't thought of 4-cyl screamers. So then, import stuff too would be a consideration... I've heard Honda blocks are anvils. Same with Mitsu Evos. Only problem would be the rear-wheel drive config, and turbo plumbing/exhaust would be an issue. Simplicity rules.

I'm leaning toward LS or Mod motors because of the ease of rwd set-up, and I could get to the hp neighborhood without a need for turbos.

Is there a simple adapter/tranny combo for the 4-cyl stuff?

[dieselgeek]

Re: Strongest block? SBC/SBF/LS??

There are adapters out there for Mitsu engines to GM trans / RWD.

Keisler makes an adapter for an Ecotec (my recommendation, it's tougher than any of the import blocks IMO) using a hydraulic clutch and mating it to any GM trans... (or torque converter and auto trans).

[Mr4Speed]

Re: Strongest block? SBC/SBF/LS??

How do BB Chevys and 426 Hemis compare? They seem to be pretty over built.