Aftermarket block street strokers.

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Dragonbat13

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So with the 400 block the 470 seems to be the street strokers with the wrist pins out of the ring lands and the extra support of the skirts. At least it seems that way for most, some always disagree. That's cool.

My question is with regards to the 4.5 bore aftermarket 440 blocks.

How much stroke can a builder get with the RB before the pistons get too short for the street considering the conditions mentioned above?
 
Dragonbat13 said:
So with the 400 block the 470 seems to be the street strokers with the wrist pins out of the ring lands and the extra support of the skirts. At least it seems that way for most, some always disagree. That's cool.

My question is with regards to the 4.5 bore aftermarket 440 blocks.

How much stroke can a builder get with the RB before the pistons get too short for the street considering the conditions mentioned above?
Click to expand...
Minus half stroke plus rod length from deck height gives possible piston height.
 
When you go with the 4.500" stroke crankshaft and use a 7.100" long connecting rod you'll end up with a compression height of of 1.355"

Anything shorter than that and I personally wouldn't want them on a street engine with a 4.500" diameter piston. I always ask my customers do you want to try and get the last 2-3 HP

out of it, or do you want an engine that will last. Unless you're financially well off or have a sponsor paying for regular rebuilds, running short compression height piston that require

skinny ring package are a recipe for trouble down the road.

Tom
 
4.250 stroke is typically the limit for a true street engine. 4.50 fits, but usually forces you to go with external oiling which isn't a street friendly option. But this all depends on what you mean by "street". A daily driver is one thing, a hot rod that goes to the Dairy Queen once a month is a different thing.
 
At a 4.250 stroke, I think plenty of power can be made for most purposes.
 
I'm building a 522 with a 4 3/8 arm and a 7.1 rod, and the pin is not in the ring land. I'm hoping to avoid the external oiling, but if I have to, I have to.
It's going to be a couple times a month in-n-out annoyer.
 
You can make great power with a 470 (400 with 3.91 stroke) and the question becomes, how much HP and TQ do you need for a "street" car. I just dynoed my 470 and it had 658HP and 689TQ. It is going to be hard to get it to hook up on the street with that much TQ as it is, but will be a lot of fun.

There is also the choice of cam, heads, and intake that play a roll as opposed to just straight cubic inches. Putting the best heads you can afford and selecting the right cam for what you want it to be is what I found makes the biggest difference. I have seen 540 motors make less HP and TQ than my 470 due to heads, cam, and intake.

Good luck with your build!

IMG_3497.jpg
 
1967 Cuda said:
You can make great power with a 470 (400 with 3.91 stroke) and the question becomes, how much HP and TQ do you need for a "street" car. I just dynoed my 470 and it had 658HP and 689TQ. It is going to be hard to get it to hook up on the street with that much TQ as it is, but will be a lot of fun.

There is also the choice of cam, heads, and intake that play a roll as opposed to just straight cubic inches. Putting the best heads you can afford and selecting the right cam for what you want it to be is what I found makes the biggest difference. I have seen 540 motors make less HP and TQ than my 470 due to heads, cam, and intake.

Good luck with your build!

View attachment 1716199431
Click to expand...
Lovely lol, I 100% agree with the 470

IMG_20231027_184731186_HDR.jpg
 
Dragonbat13 said:
So with the 400 block the 470 seems to be the street strokers with the wrist pins out of the ring lands and the extra support of the skirts. At least it seems that way for most, some always disagree. That's cool.

My question is with regards to the 4.5 bore aftermarket 440 blocks.

How much stroke can a builder get with the RB before the pistons get too short for the street considering the conditions mentioned above?
Click to expand...
My 470 has a 6.700 bbc rod & 1.320 ch pistons.
The pin is in the rings. That is not an issue at all.
If however you run the short rod version you will have a slightly taller piston. It's .160 difference.
One thing I would say for any new engine, not necessary but it makes a difference. Send your pistons to "line to line coatings" that stuff works very well.
 
I don’t know big blocks, but why is the external oiling option not very street friendly? Is it just packaging?
 
Building my 522 cause that's the block, crank, and pistons I have.
With a 4.5 block, 4 3/8 crank, you end up with 557 inches. You'll need GOOD heads!
 
Well, I've always read the safe limit on the low deck factory block is around 650 horsepower. And that's possible with some TF 240 heads and a SFT cam. If I were to go over to bushed lifters, the expense of a solid roller, and max wedge heads then I would rather put all that down n the stronger, raised RB blocks that can achieve a 4.5 inch bore. It would be a rather nasty street engine.
 
AndyF said:
Packaging and leaks
Click to expand...
My milodon s/s pan has a huge washer on the outside which I noticed rides on the pan rib and caused a very annoying slow leak. That's a soon to be fixed project.
 
MOPARMAGA said:
My milodon s/s pan has a huge washer on the outside which I noticed rides on the pan rib and caused a very annoying slow leak. That's a soon to be fixed project.
Click to expand...
Yep, common problem with Milodon. They don't pay attention to where they punch the holes so sometimes the washer ends up on a rib. When they make an oil pan for external oiling they should use a different rib pattern. Very simple engineering fix but they have never made the fix in 50 years of production.
 
33IMP said:
Building my 522 cause that's the block, crank, and pistons I have.
With a 4.5 block, 4 3/8 crank, you end up with 557 inches. You'll need GOOD heads!
Click to expand...
Like 915 HP cast iron heads lol
 
AndyF said:
Yep, common problem with Milodon. They don't pay attention to where they punch the holes so sometimes the washer ends up on a rib. When they make an oil pan for external oiling they should use a different rib pattern. Very simple engineering fix but they have never made the fix in 50 years of production.
Click to expand...
Yeah, that is a simple fix. Just making the washer a smaller diameter would fix it.
 
1967 Cuda said:
You can make great power with a 470 (400 with 3.91 stroke) and the question becomes, how much HP and TQ do you need for a "street" car. I just dynoed my 470 and it had 658HP and 689TQ. It is going to be hard to get it to hook up on the street with that much TQ as it is, but will be a lot of fun.

There is also the choice of cam, heads, and intake that play a roll as opposed to just straight cubic inches. Putting the best heads you can afford and selecting the right cam for what you want it to be is what I found makes the biggest difference. I have seen 540 motors make less HP and TQ than my 470 due to heads, cam, and intake.

Good luck with your build!

View attachment 1716199431
Click to expand...
Hopefully some more time was spent tuning that. Those AFR numbers are “abort the pull” lean to me. Probably some more power there too.
 
Dragonbat13 said:
Well, I've always read the safe limit on the low deck factory block is around 650 horsepower. And that's possible with some TF 240 heads and a SFT cam. If I were to go over to bushed lifters, the expense of a solid roller, and max wedge heads then I would rather put all that down n the stronger, raised RB blocks that can achieve a 4.5 inch bore. It would be a rather nasty street engine.
Click to expand...
If you are comparing stock 400 blocks to stock 440 blocks, consensus is that the 400 is (usually) stronger.
It's not fair to compare a stock 400 to an aftermarket RB, lol.
I think, if I were trying to build a maximum effort engine, I'd try for a 4.500 bore aftermarket B block, aluminum or iron..... yet to be determined, lol
 
TT5.9mag said:
Hopefully some more time was spent tuning that. Those AFR numbers are “abort the pull” lean to me. Probably some more power there too.
Click to expand...
Oh yeah, yikes that's lean. I was just looking at mine..I have some distribution issues apparently with my tunnel ram.
 
MOPARMAGA said:
Oh yeah, yikes that's lean. I was just looking at mine..I have some distribution issues apparently with my tunnel ram.
Click to expand...
Tunnel rams are usually pretty good. But at least you have 8 barrels to corner jet if you have to.
 
TT5.9mag said:
Hopefully some more time was spent tuning that. Those AFR numbers are “abort the pull” lean to me. Probably some more power there too.
Click to expand...
We only made two pulls due to the AFR issue. I was just on the dyno to check for leaks and run in. The carb used was a 950 HP dyno carb and I am going to run sniper xflow fuel injection in the car and will do more testing in the car on a chassis dyno when the car is all together. I agree that there is more power once things get dialed in and I play with the timing a little.
 
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