Has anyone built a 541 with the stock block or 528? Is the block just to weak to handle big hp 900-950?

I had a 528 RB in a factory 68 block. I filled it to the top of the freeze plugs and had to plug the oil pickup tube and run an external oiling system. I ran stage 6 max wedge port heads. It was an over achiever. Birdtracker

Did it get hot? Drag race only or any street use?

I'd limit a stock 440 block to a 505 with a 4.25 crank and roughly 750 or maybe 800 hp. Anything more than that then step up to an aftermarket block.

Damn block are so much money now its crazy unless I could find an mopar block M

If you can afford to make 900-950 horsepower the cost of a good block should be peanuts to you.

Compared to a BBC very expensive. I have Weston machine do all my work. All said and done 9-11k ready to go.

mine did not run hot. It was a true street car / race car. 11.5-1 compression and a .640 flat tappet. Birdtracker

Nice build I like it!!! Torque monster I bet!!

I've had two different blocks crack the main webbing under cylinders #1 and #3, one 1969 HP 440 block and one 1963 426 M.W. block
Neither one of those motors made over 600 HP
I wouldn't do what your asking about
How much will it cost you if that block fails and doesn't make you wreck the car and all the race parts versus having a catastrophic engine failure at WOT above 5000 RPM in high gear scattering the motor and make you crash the car :

Yep, that is correct. I'm building a Ford 521 right now. It will make 850 hp using a stock late model Ford truck block and Kaase SR-71 heads. I'm not sure I'll ever build another Mopar big block for myself. Just too expensive.

N/M

I'd build the 543 but I wouldn't be building something for maximum hp. I'd rather build a BIG mild motor, no need for insane rpm no need for big compression. Just a big torque monster.

So I have built a bunch of +500 Mopar strokers in the last few years. And our current package comes in right around 800hp....Now I have not pushed one much past that with a stroker kit....We have had zero issues at that level. We run good parts, and a girdle on everyone. I do not like a partially filled block, it heats up super quick, and can be a pain to cool.

The key for us, we keep the rpm down under 7k...Typically 6500...For all the big strokers.

I also have one engine its only a +.030 440, but its blown, and it has been pushed to 1200hp on 20lbs of boost...It is partially filled and requires an engine oil cooler to keep cool and has the biggest girdle I have ever seen and aluminum caps all locked in......One of those kits with caps and girdle.

Now at 900hp, I would say, your flirting with disaster in a stock block. Its not going to hold up to weekly thrashings like an aftermarket block...If its an occasional trip down the track and turbo charged where it does not see the track weekly, it might hold up for a while.

How fast are you looking to go? Is a better question. Up to mid nines ok, 8's and faster You definitely have the money for a after market block.

800-900 hp your talking mid/low 8's

Because HP numbers are thrown around here liberally, you'd be better to ask the question differently. lf you stated your targets like; "mid-high 8's in a 3300lb dedicated drag car (with driver) ON MOTOR" you'd get better answers. I may have misunderstood your post but if someone lead you to believe they could do such a motor for 12000 from scratch that'd live, you were misled. Use the google search on here, there are plenty of good posts about how we've gone about it. And use Wallace Racing Automotive calcs to get an idea of what you need for HP to reach your target.

Just giving you credit for saying it first.

Here's an example using Wallace...

"Your ET / MPH computed from your vehicle weight of 2950 pounds and HP of 700 is 9.41 seconds and MPH of 143.64 MPH."

60 Foot 1.29
330 Foot 3.73
660 Foot 5.86
660 MPH 116
1000 Foot 7.71
1/4 Mile ET 9.29
1/4 Mile MPH 142.68

My tall filled 400 block makes 850 on a good day but its only a 4.15 stroke. And the 400 are better in the main web at handling that.

I definitely wouldn't push a 440 block past that.

You'll get 10 people that say it won't to every 1 person that says it will.

We have no issues with a stock RB block a that has been main studded and using a 4.25 stroke crank.

Horsepower varies depending on what nitrous jet is in it that weekend.