FE Block Strength - Engine Block Stress Math Resource Question

[Barry_R]

It's "our fault" that we do not really know how far you can push a garden variety FE under boost.  Most FE guys are pretty old school and pretty conservative by nature.  In comparison, the LS, modular, and 5.0 guys are more attuned to the idea of the engine as a sacrificial, disposable item.  Throw nitrous or boost or both at it until it goes kaboom and then replace the "bullet".

I have a sneaking suspicion that if you handed a forged piston 390 to a tuner he'd be making absolutely stupid power on boost & EFI before anything would break.

Hey Jay - I have a perfectly good 390 block with a broken bellhousing ear and a nice cast crank.  Wanna throw the ProCharger from the Mach on it and see how far it'll go with the intention of destruction?  All we need is to bung a Streetmaster up and I can run my stand alone EMC FAST harness on it.  We can flip a coin on who's dyno room get the oil dri treatment 

Might make us famous on Youtube.....

[Joe-jdc]

I have some old Edelbrock heads that are new/ported/experimental, and the Streetmaster that won the FE shootout for torque.  I'm game to lend them out.  Also have a Victor, StreetDominator, that might work.  Joe-JDC.

[country63sedan]

I have no parts to offer in this adventure, but I do like the idea of scientific destruction. I'm darn curious what a mildly built 390 would put out before ungodly boost destroyed it. Later, Travis

[WConley]

Oh wow   

I bet you'd be amazed at how much the ole' deep skirt block can take, at least for a short flog.  Let's make it fun and add nitro to the fuel 

[machoneman]

Hey, wait up guys! I can source about 5 gallons of 100% nitro and cut it with alky to say 90%.

Wow, with the charger pulleys on 'kill' and 90% in the tank .....an easy 2,000 hp+....or bust! LOL!

Geez, I go so excited I missed that Bill said the same above!

[Joe-jdc]

I have a ProCharger and intercooler for 4.6 SOHC, if someone had the brackets for a FE, or I have a S trim Vortec pullied for 14 psi and 8 rib belt, just need brackets for FE.  The possibilities are endless---.  Joe-JDC.

[jayb]

Boy, this sounds like too much fun to miss out on.  I have two turbos sitting here, each one good enough for 1000 HP.  I also have the Blue Thunder MR heads from my supercharged motor, and that Victor I bought from you Barry that would just bolt right on.  I could build a grenade in no time, and just keep turning up the wick on the turbos until the rods went flying.  Or the crank.  Or the block.  Whatever.

Problem for me is that I'm officially pressed for time now to get ready for Drag Week.  Can we table this grenade project until October?

[westcoastgalaxie]

Yes, please do. Whatever it takes, I will wait patiently. If I was closer I would offer up grunt work to help out. I have wondered the same thing "what is a 390 good to with low rpms and a lot of boost?" I have dreams of building up my 64 comet and using turbo'd low buck 390's.

About the block layout, good to know. If Shoe was around I would ask him for more detail. I wonder if the casting is too thin in the critical areas that the twisting motion shows up as the first failure mode.

[Rory428]

I`ve never played with blowers or turbos, although I have run plenty of nitrous oxide thru FE`s years ago. My nearly bone stock R code 69 Mach 1 improved from mid 13`s in the 1/4 mile, to high 11`s at 115mph with a 125HP NOS kit. Stock exhaust manifolds with crappy crimped 2 1/4" $100 dual exhaust system, stock torque convertor, 3.50 gears, cast pistons, stock fuel pump, the only problem I ever experianced was bending several stock pushrods when the engine overrevved due to wheelspin on the street "on the bottle" in low gear. Shifting at 5600 RPM, this combination was virtually bulletproof for the 2 years I ran it like that. However, the first 390 I had in my Fairmont suffered major destruction "on the bottle". It used a "105" D4TE block, main studs, new Lemans rods with forged pistons, and ran mid 11`s @ 114 MPH with a foot braked C6. A 175HP NOS kit pushed the car to 10.2-3ETs at over 130 MPH, but after about a season of such useage, ALL the main webbing between the cam & the crankshaft tore out of the block, the crank was in 5 pieces. The right side of the oil pan rail area was bulged out noticably, the starter nose snapped off, and the flexplates starter teeth had carved a large groove in the bellhousing area, as well as splitting the entire bellhousing area from pan rail to pan rail. The front pumps stator support was also snapped off. The photos were posted on the FE forum about 10 years ago by Dave Shoe. This carnage happened in 1989 or 1990, and I`ve been naturally aspirated ever since. I think Jays analogy of the big tired, 6000 RPM clutch dumps being hard on the non crossbolted FE have much merit: after the 390s demise, I have ran 4 or 5 different 428`s thru the Fairmont. 2 died from broken connecting rods after years of racing, when used with the C6, but the several split cylinder walls,& cracked main webbing has all occurred in the last 12 years since I replaced the C6 with a 4 speed Jerico & clutch. The performance improvement with the 4 speed is considerable, but it sure appears the added stress to the block is as well. Although a crossbolted block would certainly help, its no garantee that split main webs will never happpen. The 427 block in DaleP`s 67 Mustang suffered a split main web, right thru the main bearing oil hole, just like my 428 did.

[cammerfe]

When considering how an FE will act under boost, it might be well to consider Pete Robinson and some of the other pioneers who ran Cammers on boost-'n'-pop.

KS

[WConley]

Sounds good Jay.  All the more time to pass the hat around and at least get a set of forged pistons into the thing. 

Maybe somebody has some old TRW's lying around.  They're bomb proof and the noise will probably delay you shutting the test down until the crank really is on the floor

I like the idea of boosting the snot out of it and keeping the revs down.  Maybe we can put some Caterpillar emblems on the valve covers.

[machoneman]

Well Jay if you are serious, October works for me 

And yes, Robinson, Kalitta, and other did run about 90% (and often less for match races) with cross-bolted 427 blocks and often Milodon's steel main cap support.  But, they didn't last long per testimonials by Ed Pink and other SOHC builders with the mains cracking up through the unused cam tunnel.  The latest nostalgia fuel car (and also the fastest drag racing SOHC of all time) was/is the Bach & Gould supercharged F.E.D. and they also lost too many stock block engines at least until they had some late model Shelby or Pond blocks. Btw, dream wheel work on Kalitta's triple win '67 rail showed between 1,900 and 2,100 hp for his best 7.17 e.t  IIRC (Schiefer slipper clutch, smallish 6-71, single pump, single mag).   

Best to skip the nitro come to think about it (too prone to detonation) and instead go for max turbo or 'charger boost on gas. 'Course, these aren't my parts....LOL !
   

[cammerfe]

Very likely the way to go about things would be to use some of the characteristics Jim Dove has incorporated into his 'Funny Car' engine. The (Cammer) heads have the intake and exhaust runners from KB 'fuelie' heads grafted in and the block doesn't have a cam tunnel.

On an allied note, the Jag aj27 engine in my ECTA car has water jackets that only extend down the cylinder walls about an inch-and-a-half and are solid from there on down. The sleeves are cast in place, and both the head studs and the plethora of studs that come up from the bottom are very long to make use of the entire mass of things to help hold it all together.

KS

[BigNate]

It's "our fault" that we do not really know how far you can push a garden variety FE under boost.  Most FE guys are pretty old school and pretty conservative by nature.  In comparison, the LS, modular, and 5.0 guys are more attuned to the idea of the engine as a sacrificial, disposable item.  Throw nitrous or boost or both at it until it goes kaboom and then replace the "bullet".

I have a sneaking suspicion that if you handed a forged piston 390 to a tuner he'd be making absolutely stupid power on boost & EFI before anything would break.

Hey Jay - I have a perfectly good 390 block with a broken bellhousing ear and a nice cast crank.  Wanna throw the ProCharger from the Mach on it and see how far it'll go with the intention of destruction?  All we need is to bung a Streetmaster up and I can run my stand alone EMC FAST harness on it.  We can flip a coin on who's dyno room get the oil dri treatment 

Might make us famous on Youtube.....

I'd gladly send up a streetmaster if you send it back with injector bungs installed when you are done with it...     (I've given some thought to getting a running JY 390 and putting boost on it, keeping it in a very safe A/F range, and seeing how far it can go... - but so far time and money have not played along)

My turbo obsession started with this guy who is the consumate "do something with what you have and see how far you can take it..." kind of guy... 


Who took this car


Added slicks, boost, and a JY windsor to make it do this...


And started collecting things like this (left column)...


If memory serves he had less than $3000 in a car that went 110 in the 1/8th in a 3200lb + car.... :-)  His "spec sheet" reads:

Specifications for 2000:

     1972 351W short block, all stock, new rings and bearings.
     Oil pan and pickup from a 351W Crown Vic.
     GT-40 iron cylinder heads all stock (produces 8.0 to 1 CR.).
     2 - Garret TO3s from 85-86 Tbird TCs, .63 exhaust A/R.
     Custom Upper Intake
     1990 Ford truck EFI lower intake
     75 mm throttle body
     Crane camshaft  216/228 @ .050" duration and .482/.496" lift.
     Electromotive TEC-II DFI system
     24x9x3" air - air custom intercooler
     8 - 54 lb/hr low impedance injectors.
     1.5" shorty headers, flipped upside-down and elongated bolt holes to align with exhaust port.
     Two fuel pumps routed in parallel - one in-tank (255 L/hr), one in-line (~100 L/hr).

Specifications for 2001:

     1972 351W short block, bored .030, crank cut .010/.020, line honed, zero decked.
     Sealed power hyperutectic pistons with 0.190" deep dish (8.5:1 CR)
     Resized 351W truck connecting rods.
     Crane Cam 228/228 @ .050" .512/.512" lift.
     Crane valve springs.
     Gasket matched lower intake manifold

[BigNate]

If you are looking at going down this road you could very easily hang a big single industrial junkyard turbo (industrial - diesel truck unit) off of a couple of factory log exhaust manifolds (perhaps two of the ones on top here)



I dug up an old spreadsheet and my rough math says that a 390CID engine at 24 PSI and a .8 VE @ 5000RPM would eat about 96 lbs/min and be making about 1000 HP (again very rough model). 

I'd think that an old HX60 would do the trick...  Spool will be slow and you'll have to support the behemoth with something - but it will move more air than needed...