**600hp sbm block limit? Or is it bs!!**

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I had a 360 block cracked through the valley, it was stock & out of a 78 truck...

I think the 600 limit is complete horse sht.

Aside from precise machining & assembly, I believe core shift & tune are the important factors.

JMO

You and I both and by the time this thread is done, there will be a whole new onslaught of believers that this "Myth" is indeed Horse sht.
 
we ran many 340 blocked 358 motors back in the late 70s early 80s all pushing over 750hp on dirt with a two barrel carb. on alcohol had all kinds of failures rods cranks and pistons don't remember any block failures.some were TA blocks some were 4 bolt some not..BUT I KNOW all racing engines are going to the same place just some get there sooner than others.....Artie

You are correct, all engines will eventually "pass away" to some extend. Your post here also puts the "Myth" in the burial ground! I know for a fact those engines are ran so damn hard and at High RPM's for a long long time.

Thank you for your first hand knowledge on this subject!

Can I ask what you guys were Revving these engines to? I am sure everyone will want to know.
 
You are correct, all engines will eventually "pass away" to some extend. Your post here also puts the "Myth" in the burial ground! I know for a fact those engines are ran so damn hard and at High RPM's for a long long time.

Thank you for your first hand knowledge on this subject!

Can I ask what you guys were Revving these engines to? I am sure everyone will want to know.
those engines were 15to1 for alcohol and at Winchester VA.on an 1/8Th mile track they were trunt to 8500.for 25 laps at a time not to Manichean the worm ups and qualifying..and at hagerstown speedway in md.a 1/2 mil was turnt to 7500 to 7800 for the same amount of laps as va.one thing we did do was change oil every week and used strait 50wt.kendall oil.and every 500 laps would change rod bearings..never had a baring problem.........Artie
 
Thanks for the information Artie!

I would formally like to Welcome everyone to the forabodiesonly "Myth Busters Show"
 
A good friend has a rail that ran 7.2 at 188. With a sbm.. It's a x block on alchohol and nitrous. Has seen 9500 rpm multiple times. Has been together for a long time and many passes.. Hasn't seen any problems as far as block cracking or breaking. Its a iron head motor to..
 
Well i got no pics, but if your looking for more than 600hp i know that using mounts on the block will show the walls are effected by using a mount...same holds true for the bb's
So you want to use ears when you get beyond 450hp...
Are you using a la or mag.... i wouldn't trust a mag block


My Brodix headed Mag block has seen 655hp 590TQ on a chassis dyno. Lifted at 6200@ 14#s boost while still climbing. Split the intercooler. and had fuel issue with my Aeromotive A1000... New setup is done, bumped up the fuel pump, swapped my 6AL for a 7. Getting ready for another dyno tune. Fully expect over 700HP with C16. No headgasket issues which was my big concern. I am plate mounted too.
 
My Brodix headed Mag block has seen 655hp 590TQ on a chassis dyno. Lifted at 6200@ 14#s boost while still climbing. Split the intercooler. and had fuel issue with my Aeromotive A1000... New setup is done, bumped up the fuel pump, swapped my 6AL for a 7. Getting ready for another dyno tune. Fully expect over 700HP with C16. No headgasket issues which was my big concern. I am plate mounted too.

Can you go into more detail on what you are using for Boost? Is it Supercharged, Turbo's or Blower? Plate mounted so your on the Juice too?

What head gaskets were you using when they lifted?
 
I'm just throwing this out there on the rods and piston failing in these engine could it be the rev limiter casing the engine to shake at high RPM?? leading to failer just a thought.
 
Speaking as a mechanical engineer, it would be hard to get a definitive answer. The loads depend on both torque and engine speed. Horsepower is the product of the two. Torque relates to the primary forces of combustion - force on the piston and thru the connecting rod. However rpm brings in imbalance forces, which can be larger at very high rpm. Both forces cause failures from "fatigue" which is applying the load many times, so the claim "all racing engines eventually fail" is probably true. You add in statistical variation in small sample numbers and hard to be definitive. The engines vary in balance and makeup of the block. Cast iron is very sensitive to even a small occlusion in the material, which can be a site where a crack starts. Cast iron parts are probably much less predictable in failure than forged connecting rods, which are a more homogeneous material with more reproducible manufacturing.
 
Can you go into more detail on what you are using for Boost? Is it Supercharged, Turbo's or Blower? Plate mounted so your on the Juice too?

What head gaskets were you using when they lifted?

You have a misread on his post. He meant he lifted foot off pedal at 6200rpm while on Dyno. The head gaskets were good. And by plate mounted he means how engine is attached to frame, no stock motor mounts. Just an FYI for ya ;)
 
You have a misread on his post. He meant he lifted foot off pedal at 6200rpm while on Dyno. The head gaskets were good. And by plate mounted he means how engine is attached to frame, no stock motor mounts. Just an FYI for ya ;)

Yeah I do that sometimes. He was talking about his head gaskets not giving out so I assumed........ My bad on that one!
 
I thought about not posting on this one.. I'm one of the ones that says to get a new block and I really dont feel I need to defend myself. I read this entire post as an attempt at personal attack. But, Bill gets real close to why I say what I say so...

Speaking as a mechanical engineer, it would be hard to get a definitive answer. The loads depend on both torque and engine speed. Horsepower is the product of the two. Torque relates to the primary forces of combustion - force on the piston and thru the connecting rod. However rpm brings in imbalance forces, which can be larger at very high rpm. Both forces cause failures from "fatigue" which is applying the load many times, so the claim "all racing engines eventually fail" is probably true. You add in statistical variation in small sample numbers and hard to be definitive. The engines vary in balance and makeup of the block. Cast iron is very sensitive to even a small occlusion in the material, which can be a site where a crack starts. Cast iron parts are probably much less predictable in failure than forged connecting rods, which are a more homogeneous material with more reproducible manufacturing.

Thanks Bill.
 
i hope a stock block do hold up becasue im building a 900+hp 400ci sbm with a f1 procharger.
 
I also hope a stock block holds Im suppose to make around 520 all motor then 50-75 shot of nitrous hmm
 
I thought about not posting on this one.. I'm one of the ones that says to get a new block and I really dont feel I need to defend myself. I read this entire post as an attempt at personal attack. But, Bill gets real close to why I say what I say so...



Thanks Bill.

It's not a personal attack , you and a few other guys always say
To get an aftermarket block. I am asking for proof and evidence of
What is always being preached. There most obviously is none and
I am bringing it to the attention of everybody who reads your posts
And takes it to heart. Some of them put off their decision to build
Their engines based off what A few of you are telling them.

The evidence proves that these stock blocks will take a heck of alot
More than what you and a few others are saying they will.
 
I made over 600hp using a Magnum block. I got a 6psi of boost and add a 150 shot of nitrous. The engine was together for many years. The #7 piston skirt failed filling the pan with debris. 3800 pound Dodge Mirada, 10.6@128mph, street 275/60/15 tires.
 
I really don,t want to see this thread become a pissing match,cause I respect everybodies opinions on any small block built.Wether it,s turbo,supercharged,nitros,E85,alchohol we all can learn from others and their goals,also their mishaps at reaching higher HP numbers.Brian at IMM Engines did post a small block dynoed at 640hp or was it 620?I think the real question is" How long will it last" without block failure.After only 1 day with this thread,already we,ve heard more good than bad:DLets hear some more KILLER SMALL BLOCK stories!=P~
 
I really don,t want to see this thread become a pissing match,cause I respect everybodies opinions on any small block built.Wether it,s turbo,supercharged,nitros,E85,alchohol we all can learn from others and their goals,also their mishaps at reaching higher HP numbers.Brian at IMM Engines did post a small block dynoed at 640hp or was it 620?I think the real question is" How long will it last" without block failure.After only 1 day with this thread,already we,ve heard more good than bad:DLets hear some more KILLER SMALL BLOCK stories!=P~

I hear you Scott. No pissing matches allowed.

We have heard of Big Number Small blocks living for Years on this thread at well over what most believed the limits of the block were.
I believe eventually all will fail depending on use and abuse. At some point they will all pass away, this is a fact!

So post up your Big Power Small Blocks using a Factory Block!:D
 
Is still alive Jefflock FABO member has the motor now


[ame="http://youtu.be/ssRAHemsB6U"]http://youtu.be/ssRAHemsB6U[/ame]
 
Speaking as a mechanical engineer, it would be hard to get a definitive answer. The loads depend on both torque and engine speed. Horsepower is the product of the two. Torque relates to the primary forces of combustion - force on the piston and thru the connecting rod. However rpm brings in imbalance forces, which can be larger at very high rpm. Both forces cause failures from "fatigue" which is applying the load many times, so the claim "all racing engines eventually fail" is probably true. You add in statistical variation in small sample numbers and hard to be definitive. The engines vary in balance and makeup of the block. Cast iron is very sensitive to even a small occlusion in the material, which can be a site where a crack starts. Cast iron parts are probably much less predictable in failure than forged connecting rods, which are a more homogeneous material with more reproducible manufacturing.

That's why i like the AL blocks better. . . just those A blocks are so expensive
 
Nice run! That equals to a 9.80 ish 1/4 Pass, surely moving some pavement.
What was the engine combination? Please post the recipe and how much power it was making.

414 cid 360 MOPAR block ,flat top pistions making 11.42 compression, INDY cylinder heads with minor pocket blending, an old school solid roller super stocker .700 ish lift cam shaft. making 600 hp. 600 tq. , car was getting 1.31 60 ft . times 904 tranny behind a PTC 5,200 verter , rear was 8.75 wth 4.30 gearing

100_1170_00.jpg


100_1167_00.jpg
 
Mad Dart is leading the way once again. Even running a FABO version of mythbusters. The truth is out there.... somewhere. Subscribed. :thumbup:


Wylde1.
 
Mad Dart is leading the way once again. Even running a FABO version of mythbusters. The truth is out there.... somewhere. Subscribed. :thumbup:


Wylde1.
The only thing missing is the explosion videos.....
 
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