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B Block or RB Block for 500 ci build

m79ded

m79ded

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Hi
in terms of reliability and performance on a mainly driven street car, good service life, cooling issues, stress on block etc... Would it be better to put together a B or RB? Or it's not an issue either way. I realize B has a steeper rod angle but is it a big thing or just splitting hairs, the B also has a lighter assembly.
thanks
 
Go B, they are stouter than an RB.
 
m79ded said:
Hi
in terms of reliability and performance on a mainly driven street car, good service life, cooling issues, stress on block etc... Would it be better to put together a B or RB? Or it's not an issue either way. I realize B has a steeper rod angle but is it a big thing or just splitting hairs, the B also has a lighter assembly.
thanks
Click to expand...
I would say the low deck "B". The B is a bit narrower and sits a bit lower for hood clearance, but also less selection of intake manifolds compared to the RB. Also, 400 blocks used to be really cheap (not sure how much they sell for now?), and 440 blocks are getting harder to find and more expensive.

Don't worry about the rod angle. The 512" B (4.25 stroke) is a nice combination for a street/strip car. The shorter stroke 499" (4.15 stroke) is nice if you plan to spin the engine 7,000+ RPM.
 
451Mopar said:
I would say the low deck "B". The B is a bit narrower and sits a bit lower for hood clearance, but also less selection of intake manifolds compared to the RB. Also, 400 blocks used to be really cheap (not sure how much they sell for now?), and 440 blocks are getting harder to find and more expensive.

Don't worry about the rod angle. The 512" B (4.25 stroke) is a nice combination for a street/strip car. The shorter stroke 499" (4.15 stroke) is nice if you plan to spin the engine 7,000+ RPM.
Click to expand...

I surely did notice the extra room for headers and hood clearance.
 
Don Chapel said:
I'm building a 73 400 block. Will be a 512ci using 440 source rotating assy.
Here is information on blocks:
http://440source.com/blockinfo.htm
Click to expand...
Thanks for the info. That's a great way to go, I was thinking the same but I have a 400 block that was decked .010 and that 1.32 piston comes out of the hole. I was looking at the Diamond with 1.305 CH. I will do up the math and see which one works well in terms of CR. With 91 and 93 pump gas I think I should stay at 10.5 max and dynamic of 8.4
 
I just started a stroker project on a 1975 400 block using a 440 source 470 stroker kit. After chatting with a few engine builders here are my 2 cents. The 400 block is stronger and will allow for slightly easier header clearance but if you go with TTI that doesn't really matter because they all fit fine. My 470 combo will allow for lots of street use without overheating issues, piston slap, etc., which is something to consider. The main problem with a low deck would be the intake options. If you just want a single 4bbl there are lots of options, but if you want to get into some "cooler" stuff like 2-4bbl, cross ram, or whatever the choices are limited. The engine builder im using has done quite a few low decks and actually competed in the engine masters competition around 10 times so I trust him when he says dont go over the 470ci kit on the low deck for regular street use. my original plan was a 500 or 512 because i simply liked the sound of over 500ci! but in reality, he said to save those ci for the RB blocks.
 
Steve009 said:
I just started a stroker project on a 1975 400 block using a 440 source 470 stroker kit. After chatting with a few engine builders here are my 2 cents. The 400 block is stronger and will allow for slightly easier header clearance but if you go with TTI that doesn't really matter because they all fit fine. My 470 combo will allow for lots of street use without overheating issues, piston slap, etc., which is something to consider. The main problem with a low deck would be the intake options. If you just want a single 4bbl there are lots of options, but if you want to get into some "cooler" stuff like 2-4bbl, cross ram, or whatever the choices are limited. The engine builder im using has done quite a few low decks and actually competed in the engine masters competition around 10 times so I trust him when he says dont go over the 470ci kit on the low deck for regular street use. my original plan was a 500 or 512 because i simply liked the sound of over 500ci! but in reality, he said to save those ci for the RB blocks.
Click to expand...
Sounds good Thanks BTW who is your Engine builder
 
Either will work,blocks are somewhat personal preference although the 400 has a few advantages. What kind of service life are you looking for? What do you want performance wise?
 
m79ded said:
Hi
in terms of reliability and performance on a mainly driven street car, good service life, cooling issues, stress on block etc... Would it be better to put together a B or RB? Or it's not an issue either way. I realize B has a steeper rod angle but is it a big thing or just splitting hairs, the B also has a lighter assembly.
thanks
Click to expand...

Either will work just fine. For a street car you might want to think more about which header you'll be using and which intake manifold you want and stuff like that. Intake manifold selection for the B engine is pretty slim and there are not as many header choices. Main bearing selection kind of sucks for the B block too and there are fewer crankshaft options for the B.
 
68 HEMI GTS said:
Either will work,blocks are somewhat personal preference although the 400 has a few advantages. What kind of service life are you looking for? What do you want performance wise?
Click to expand...
I drive car to shows and go bracket racing a few times a month. Had a 440 in car for years, put a 451 in it 2 years ago and was very impressed with the difference, It revs very quick made good torque with a 228 hydraulic and eddy RPM intake, headers fir like a glove also. Was toying with idea to go to bigger inch motor to get into 11's so I asked people on this forum that have done both for opinions. And so far they are great. What I was spooked about is that I was told by someone about rod ratio being very low on the B and it will wear out quickly, be hard on rings and block, overheat etc.... So I am asking advise.
 
m79ded said:
I drive car to shows and go bracket racing a few times a month. Had a 440 in car for years, put a 451 in it 2 years ago and was very impressed with the difference, It revs very quick made good torque with a 228 hydraulic and eddy RPM intake, headers fir like a glove also. Was toying with idea to go to bigger inch motor to get into 11's so I asked people on this forum that have done both for opinions. And so far they are great. What I was spooked about is that I was told by someone about rod ratio being very low on the B and it will wear out quickly, be hard on rings and block, overheat etc.... So I am asking advise.
Click to expand...

There is some truth to that. But in reality i think the rod ratio on a 400/511 is a 1.53. That’s the same as a 502 Chevy with a 6.135 rod. I don’t see them guys being concerned. Will you see the life of a stock stroke motor? Absolutely not. But any performance motor you beat on is gonna need maint items every so often any way such as rings and bearings.

By the way, I run a 400/511 in my roadrunner. Great street strip combo.
 
My question is what you mean by a "street driven car?"
My assumption is a stock port size head (not max wedge), no power adders, and a cam under 260 @ 0.050"?
 
451Mopar said:
My question is what you mean by a "street driven car?"
My assumption is a stock port size head (not max wedge), no power adders, and a cam under 260 @ 0.050"?
Click to expand...
TFS240 with 236 cam
 
My 400/470 is friggin’ awesome. Revs to the moon and mild mannered, that is till I hit go pedal!
 
when picking a 400 block check the casting num some have the beefiest bottom webbing of any engine block cast by anybody , not all yrs just some. far stronger than anything before or after.
 
That would be the 230 block.
 
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