Strong short block

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rrvolare

rrvolare

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Guys or Gals ........

If you had some money to build a factory LA short block stroker for the street .... how would you build it to with stand 600 -700 hp... Keep in mind that aftermarket blocks are not available yet ...not going to use racing fuel ...
- what size stroker ?
- what bore ?
- Different main caps ?
- girdle ?
- stud the block ?
- cam shaft type
- what rotating assembly ?
- what year block ?

Thanks
 
Start with a race block.

Don't waste money on a Pcar block if you think you can make that much power.



Should have read closer. If you are stuck with a Pcar block, use hard block. Keep the stroke UNDER 3.600. Use the longest rod you can get. Keep RPM down below 7k. Open the clearances up to .0028-.0003 on the rods and .0032-.0035 on the mains. Full groove mains.


Work your beads and prayer bones. Stock blocks are weak.
 
600 hp is more than a stroked stock block will handle for any decent amount of time. Their just not that strong. As YR said you can hardblock it to add strength but if you run it on the street you better live in AK or northern Canada you'll have major cooling issues.

BTW: the only stock production block that's better than the rest that I know of is the T/A block and you'll pay out the nose for one
 
Do a big block for that power level and longevity. Otherwise for a stout build... I quoted the key words.
rrvolare said:
"factory LA short block stroker for the street .... "

- what size stroker ?

Depends on the block available and how good it is.

- what bore ?

As little of a overbore as possible to retain cylinder wall thickness which equals strength.

- Different main caps ?

Just stronger ones, not 4 bolt or I should also say, not to drill the block for 4 bolts.

- girdle ?

I have seen no data on this.

- stud the block ?

Yep

- cam shaft type

Solid roller

- what rotating assembly ?

Forged, top of the line, highest strength available. Look around!

- what year block ?

What ever one sonic checks best. (Thickest in the cylinders.)
Click to expand...
Example;
340 block at .030 is great. I would like to avoid more. Sonic check X 3!!!!
4.07 X 4.00 stroke
Or
4.07 X 4.15 stroke

Forged slugs for a pump gas ratio with the head in use.
Oil mods! Pump, passages, rear
main cap oil passage.

Solid roller and fully ported heads with a min. of a 1-3/4 header pipe w/ 3 inch exhaust.

Serious single plane or dual quads.
 
To answer your question, 600-650, mid '70s block sonic tested or not, I'm sure that will start something, 4.040 bore, 3/4 fill block rock on thrust side, half fill on the other. Studs, line hone. 4" stroke lite weight forged, h beams, forged pistons. Full groove mains are you'd only option unless you really want to narrow stock width bearings for raised fillets... Oiling system depends on the rpm. That is where id start IF I only had factory blocks to tool around on.
 
Moparperf block, or stock with blockfill, 3.79" stroke, studs, solid roller cam, expensive H beam rods
 
EXcappa said:
This bloke is making the power and keeping it together
Rebuilding my 700hp 408
Click to expand...


It's better to be lucky than good.

He's getting lucky. Sounds like he is a competent tuner. That helps.

But...you can only do that so long. That's why the X block was made. The T/A blocks were failing at a rate of 90% (IIRC) and those engines were around 600-650 HP. A stock 360 will never be close to a T/A block, let alone an X block in rigidity, ring seal, bearing life etc.
 
Here is the thing about building engine (N/A) this powerful, there intended useage and how much use it gets under what kind of conditions.

With today's part, this power can be done EZ by yesteryears compare.

I'm not just so sure that it can take weekend drag racing, work all week, grocery shopping, moms hair appointment, Wednesday night drags, lil'Steven's swim lessons, Friday night movies into weekend drags for tooooo long like someone may expect it to.
 
Probably not gonna make that kind of power without lots of compression and the race juice. Lower the goal to 500-600 and it will live on the street.
 
rumblefish360 said:
Here is the thing about building engine (N/A) this powerful, there intended useage and how much use it gets under what kind of conditions.

With today's part, this power can be done EZ by yesteryears compare.

I'm not just so sure that it can take weekend drag racing, work all week, grocery shopping, moms hair appointment, Wednesday night drags, lil'Steven's swim lessons, Friday night movies into weekend drags for tooooo long like someone may expect it to.
Click to expand...

Well luckily we don't drive around at full throttle aka 600+ hp. haha Movies and cruising won't be an issue, its keeping from experiencing the crack addict effect of that much power under your foot...can you stay out of it till the strip and not blow tires off till something cracks,flys out the block, or drops a valve... That is if you don't burn a piston tuning and playing with octane. Variables.

Funny thing to me is anybody giving him an answer on the cam for this "short block" ought to know which heads are being used right??..lol!
 
Moparofficial --- i think you are concerned with RPM ?.......... Ok .... 6000-6500 rpm.., but i think that was addressed with well prepped block , quality /light rotating assembly , modified oiling.... partial hard block ... and quality fasteners/ 4 bolt mains ....only concern i have is hard block ... cooling for street driving... thanks
 
Heads to use for the goal of 700hp?
Without N02 or supercharging?

Hugesengines CNC'd Edelbrock Big Mouth heads, W5's, Brodix B1BA-MC can cut it.
Cam durations in the area of [email protected] intake.
Intake, 1X4, Indy's offering is the best I think.
2X4, MP's M1.
 
Oh! There are more than a few guys here running hard block in there engines without cooling problems. I would think the answer lies within there set ups. While I do not remember specifically how there set up, as a basic solution, a oversized cooling system is a start.
 
rrvolare said:
Moparofficial --- i think you are concerned with RPM ?.......... Ok .... 6000-6500 rpm.., but i think that was addressed with well prepped block , quality /light rotating assembly , modified oiling.... partial hard block ... and quality fasteners/ 4 bolt mains ....only concern i have is hard block ... cooling for street driving... thanks
Click to expand...
You get close but until the numbers are in...I don't pick grinds. Solid roller , no doubt.
As for cooling, most of the heat is the top of the cylinder and mainly in the heads.
 
rrvolare said:
Moparofficial --- i think you are concerned with RPM ?.......... Ok .... 6000-6500 rpm.., but i think that was addressed with well prepped block , quality /light rotating assembly , modified oiling.... partial hard block ... and quality fasteners/ 4 bolt mains ....only concern i have is hard block ... cooling for street driving... thanks
Click to expand...



If you put 4 bolt mains on a Pcar block, you are inviting catastrophic destruction. Those blocks were never designed to use the outer bolts. There isn't enough material there to hold the load, even if you use a 5/16 bolt. A 4 bolt Pcar block is weaker than a 2 bolt.


Just because stuff like girdles and 4 bolt caps are made doesn't mean you should use them. All they do is lighten your wallet.
 
Just because stuff like girdles and 4 bolt caps are made doesn't mean you should use them. All they do is lighten your wallet.

x2.
 
you can also use the eddy high port heads and have them ported and use a light weight valve train with ferrea hollow stem valves and possibly manly nextek springs

steel main caps with dowels

ati dual inertia ring crank damper
 
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