500 vs 512 from 400ci

[Miszny]

Hi

I am planning to build a new short block for my car. Idea is to use 400 heavy 230 casting block as I can't really afford buying aftermarket and I wanto to be able to use all my current top end and headers...
To make it live longer I was thnking about Milodon cross bolted mains or BCR gridle with aluminium main caps. I like the Milodon option better because it looks cleaner and I'm not really sure if I should install aluminium main caps on street driven car. It's not a gentle driven cruiser, but is sees a lot of street miles and a lot of hard miles.

Dillema between 500 and 512 is mostly based on compression height of the pistons used in these strokers. Usually 500 uilizes 6.760" rod but piston comp height is just 1.1" where 512 uses 6.535" rod with 1.3" comp height. I guess taller, more stable piston will live longer? I was thinking weather it would be good to build 500 using 6.535" rod and even custom made taller piston? Will this get me longer life out of that short block?
Last factor would be crank stroke: 4.15" for 500 vs 4.25 for 512... Is this enough of a difference to take into account as side wear factor?

Not long ago I was building a 512 with eagle light crank and it turned out very impressive. This thing revs up great, overall it made an impression and I started looking into this direction also after that.
Opinions based on experience would be great.
Any downside of these lightened 4.250 eagle cranks?

This engine with port injected nitrous will be in 1100hp range when I'm done.

Its a long therm plan, I'd probably start building after this season so there is plenty of time to work out a good combo and approach with block.

Thanks!

 

[rumblefish360]

WOW! I’d call that a dilemma. The difference in pistons are only .200. That’s not a lot IMO for what you were saying. Personally, the whole thing is about 12 cubic inches. Really nothing IMO. Even more so on a street car.

I myself would rather use the shorter stroke and longer rod combo and not worry about the .200 in distance on compression height. If there is anything to look at on pistons in this area, it would be overall height, top to bottom on the piston for longevity.

 

[MOPARMAGA]

If your crank has bbc rod journals you can use the 6.535 rod and end up with the 1.320 piston that is in the 512

 

[Miszny]

WOW! I’d call that a dilemma. The difference in pistons are only .200. That’s not a lot IMO for what you were saying. Personally, the whole thing is about 12 cubic inches. Really nothing IMO. Even more so on a street car.

I myself would rather use the shorter stroke and longer rod combo and not worry about the .200 in distance on compression height. If there is anything to look at on pistons in this area, it would be overall height, top to bottom on the piston for longevity.

Frankly it’s all partly money driven, thanks to my fantastic government my local currency lost a lot to $$ and real inflation is like 35% so this whole thing is at least 50% more effectively that it would have been a year ago. I doubt that it will come back to normal so I plan to slowly gather the best stuff I can use for this and make it happen. I’m not going to give up that easy. I see that parts in USA are going up also. Tires alone are 250$ more that I paid last year for a pair. Many local people put cars for sale or are not planning to drive their cars this season because of what’s going on.

This makes me want to use proven stuff. If things go further I may not be able to afford building something like this next time around.
When I was talking to 440 source they suggested to get shorter rod taller piston combo on the street. 500 was definitely not what they’d recommend.

 

[rumblefish360]

Gotcha. For me, I’d like to stay away from as much side wall loading as possible. Everyone else can, as someone else is fond of saying often here, pick the differences out of the fly poop for what is better and worse about this.

Good luck with your build. I’ll be reading along.

 

[Miszny]

If your crank has bbc rod journals you can use the 6.535 rod and end up with the 1.320 piston that is in the 512

I have zero parts for this build so decided to ask people with more experience than me before I start spending money.

 

[fishmens67]

Longevity? 1100hp stock block?
I like to see the B block at 470 ci max. but that's just me .

 

[qkcuda]

I did the 400/500 build using the 6.76 Chrysler journal sized rods and short pistons. I did not like that the oils rings were in the pin boss, which required a support rail. If I was doing it again I would chose the shorter rod and taller piston, both for more skirt stability and the lack of the oil ring support rail. Also the 6.535 rod uses the Chevy journal size so the clearance on the oil pickup boss with the 4.25 stroke is about the same as the 4.15 crank and Chrysler journal size. 440 source shows a 1.320 compression height piston with a 24cc dish that doesn't use a support rail, but I noticed that they say the flat top version with the same compression height does use a support rail. I would also go with a complete 440 source kit, as they come pre balanced. I ended up having to have some machining done on the crank and adding mallory metal to balance it, which increased the cost and wasted more time.

 

[MOPARMAGA]

I have zero parts for this build so decided to ask people with more experience than me before I start spending money.

I see, and agree with fisherman67 .
The 470 is great. 500 is great too has lightest Bob weight of all the strokers.
What do you want a 7000 rpm ripper or a ripper on the street mostly ?
It's kinda hard to give advice on this because I've seen them all rip and rip really good.

 

[67mprfan]

No skin in the game but I'm with the other couple of members, keep the 470 for mostly street car

 

[rumblefish360]

I did the 400/500 build using the 6.76 Chrysler journal sized rods and short pistons. I did not like that the oils rings were in the pin boss, which required a support rail. If I was doing it again I would chose the shorter rod and taller piston, both for more skirt stability and the lack of the oil ring support rail. Also the 6.535 rod uses the Chevy journal size so the clearance on the oil pickup boss with the 4.25 stroke is about the same as the 4.15 crank and Chrysler journal size. 440 source shows a 1.320 compression height piston with a 24cc dish that doesn't use a support rail, but I noticed that they say the flat top version with the same compression height does use a support rail. I would also go with a complete 440 source kit, as they come pre balanced. I ended up having to have some machining done on the crank and adding mallory metal to balance it, which increased the cost and wasted more time.

View attachment 1716044755

View attachment 1716044756

Oil ring land supports is something I’d like to avoid myself.

 

[GTX JOHN]

I have always used a Aftermarket Block @ 750+ HP.
I use 230 cold weather blooks on our Stocker but it is
475 to 500 HP.

 

[MOPARMAGA]

Oil ring land supports are neither good or bad, they are just oil ring land supports

 

[Miszny]

I see, and agree with fisherman67 .
The 470 is great. 500 is great too has lightest Bob weight of all the strokers.
What do you want a 7000 rpm ripper or a ripper on the street mostly ?
It's kinda hard to give advice on this because I've seen them all rip and rip really good.

I want 7500rpm street ripper mostly ;-)
I have 470 right now and am thinking to gather parts for next short block while I still have money to pay for them.

 

[Miszny]

I have always used a Aftermarket Block @ 750+ HP.
I use 230 cold weather blooks on our Stocker but it is
475 to 500 HP.

I remember talking to someone at Koffels 3 or 4 years ago. They advised me to get the 230 heavy casting block and claimed they made 900hp engines using those.
I wanted to either use cross bolted main caps or BCR griddle with aluminum caps.
I will probably also half fill it as I did my current 530 casting block.

 

[Miszny]

Oil ring land supports are neither good or bad, they are just oil ring land supports

I never had issues with those either, I have Wiseco pistons like that in my current 470.

 

[MOPARMAGA]

I want 7500rpm street ripper mostly ;-)
I have 470 right now and am thinking to gather parts for next short block while I still have money to pay for them.

Wow that's going to a ripper for sure, at that rpm I'd keep the stroke shorter but that's because I want an expensive engine to last. The others will do it with quality parts for sure.

 

[Miszny]

Wow that's going to a ripper for sure, at that rpm I'd keep the stroke shorter but that's because I want an expensive engine to last. The others will do it with quality parts for sure.

My current setup sees 7300 every time I take the car out. I miss this a lot. This winter is killing me. They promised global warming and I’m freezing my *** off ;-)

 

[PROSTOCKTOM]

This engine with port injected nitrous will be in 1100hp range when I'm done.

You might as well plan on buying an aftermarket block if 1100HP is your goal. A little North of 600-700HP your block is going to split down the middle and I can tell you first hand that a bored out 400 block running N20 will start cracking the the cylinder walls out before the block splits in half.

Tom

 

[MOPARMAGA]

My current setup sees 7300 every time I take the car out. I miss this a lot. This winter is killing me. They promised global warming and I’m freezing my *** off ;-)

Lol, that **** is funny & exactly true. Do you run a max wedge port head?
My 470 saw 7000 rpm on the Dyno by accident and about **** myself

 

[MOPARMAGA]

You might as well plan on buying an aftermarket block if 1100HP is your goal. A little North of 600-700HP your block is going to split down the middle and I can tell you first hand that a bored out 400 block running N20 will start cracking the the cylinder walls out before the block splits in half.

Tom

Tom, is anyone building or planning on building a big bore low deck ?
I know Indy does but I was just wondering if anyone else might , all I see is tall deck stuff for sale

 

[Miszny]

You might as well plan on buying an aftermarket block if 1100HP is your goal. A little North of 600-700HP your block is going to split down the middle and I can tell you first hand that a bored out 400 block running N20 will start cracking the the cylinder walls out before the block splits in half.

Tom

Did you use 230 casting block? It’s not your typical 400 block, a lot more meat and thicker cylinder walls.

 

[Miszny]

Lol, that **** is funny & exactly true. Do you run a max wedge port head?
My 470 saw 7000 rpm on the Dyno by accident and about **** myself

Yes my heads are max wedge and ported by Nick Wilson, they were afterwards worked a bit more by someone else.

 

[MOPARMAGA]

Yes my heads are max wedge and ported by Nick Wilson, they were afterwards worked a bit more by someone else.

Damn, yeah I guess you can get some rpm from those

 

[Miszny]

440 Source.com Everything you've ever wanted to know about blocks and more....

Please check this article. There are good photos of main webbing showing differences in block castings.
I want to use the industrial 71 230 casting block for this.

I want to ditch stock main caps and either go with Milodon cross bolted mains or with BCR griddle setup.