How much horsepower will a 400 block handle.
#21
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A 400 is hard to beat you just have to get a good block. If you find one you are in business 10's shouldn't be hard if you want to do sub 10's i would recommend sleeving it. The way to go would be to destroke the motor to a 377 same stroke as the 327 just larger bore. She will easily rev to 10 that way and stay streetable.
THe 406 will make a tune of low end torque easy to get some good heads and a good valvetrain and be in the 450+ ft/lb and with a 200 easily in the 10's without spinning her high. Just make sure you tune the car right for the nitrous. Rule of thumb is if you have a 200 hp motor and spray a 200 shot you need the capability to double the fuel. so if you had a 300 hp motor and put a 150 shot you need 150% normal fuel for the nitrous. If you do that no worry about spraying
THe 406 will make a tune of low end torque easy to get some good heads and a good valvetrain and be in the 450+ ft/lb and with a 200 easily in the 10's without spinning her high. Just make sure you tune the car right for the nitrous. Rule of thumb is if you have a 200 hp motor and spray a 200 shot you need the capability to double the fuel. so if you had a 300 hp motor and put a 150 shot you need 150% normal fuel for the nitrous. If you do that no worry about spraying
#23
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because its a cleaner revving engine and will be easier to rev a 377 higher than a 406.
I have a 383 that stalls at 3600 and spins to 8 and its on the street.
A 377 that stalled around there should easily be capable of 9k+ rpm just like a 327 will rev higher and faster than the same cammed 350. Its all about over travel distance.
I have a 383 that stalls at 3600 and spins to 8 and its on the street.
A 377 that stalled around there should easily be capable of 9k+ rpm just like a 327 will rev higher and faster than the same cammed 350. Its all about over travel distance.
#24
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You forget the weight of rotating mass, the 377 has a heavier piston, but you still need a verry big cam and valve train, making drivability not so friendly. Larger cubes makes more torque and requires less RPM, making it more street friendly. Look at the Powerstroke, Duramax and Cummins, a whopping 3500 RPM redline, and they can fly for 6000+ pound trucks.
#25
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ok not to burst your bubble but they are diesels which run about 22 to 1 compression because they are compression ignition systems but thats another story.
Torque means everything it is acceleration horsepower is just a calculation based of torque and speed and is the ability to do work not the act of doing work itself.
A cam changes the torque vs rpm curve raising it in the rpm range if you go with a larger cam. So if you raise the power band and increase torque due to better filling properties you will automatically increase horsepower. The only reason a 406 will have more torque like I said is because it has a longer stroke and torque = lever length x's force. General rule of thumb is every cube is worth around 1.5 hp which would be what 40 hp give or take???
It is ridiculous to say a 377 has heavier pistons because the bore size is the same and the rods will be the same size which has more affect on piston size than stroke length. You could even put 406 pistons in a 377 because its the same bore.
All i am saying is the 377 is a hell of an engine. Revs cleaner and faster, will rev higher and hold the rpms and will be alot more fun even on the street. Thats my next engine build is probably a 377 or a dart block destroked.
Its all about preference. If you want low end torque go with the 406 but you will never make the power you have built the block up for at lower rpms. It is worth in my opinion to go with the 377 and put a good sized cam in her. If you have the stall speed set right the car will take off fine. Sometimes if your stall is to low it will cause problems believe it or not. And if you have a manual you will have no issue with streetability.
The cam might be rated from 4-8,500 k but thats just were it really starts taking advantage of its fill properties with a manual you could probably still take off around 1500-2000 and shift at 4 and drive down the street fine. Although not necessarily the best fuel economy for that set up the best would be lightest load possible to keep her in the rpm range of peak torque. So if you are worrying about fuel economy it will be fine if you have a stall matched to the torque curve despite higher revving.
Torque means everything it is acceleration horsepower is just a calculation based of torque and speed and is the ability to do work not the act of doing work itself.
A cam changes the torque vs rpm curve raising it in the rpm range if you go with a larger cam. So if you raise the power band and increase torque due to better filling properties you will automatically increase horsepower. The only reason a 406 will have more torque like I said is because it has a longer stroke and torque = lever length x's force. General rule of thumb is every cube is worth around 1.5 hp which would be what 40 hp give or take???
It is ridiculous to say a 377 has heavier pistons because the bore size is the same and the rods will be the same size which has more affect on piston size than stroke length. You could even put 406 pistons in a 377 because its the same bore.
All i am saying is the 377 is a hell of an engine. Revs cleaner and faster, will rev higher and hold the rpms and will be alot more fun even on the street. Thats my next engine build is probably a 377 or a dart block destroked.
Its all about preference. If you want low end torque go with the 406 but you will never make the power you have built the block up for at lower rpms. It is worth in my opinion to go with the 377 and put a good sized cam in her. If you have the stall speed set right the car will take off fine. Sometimes if your stall is to low it will cause problems believe it or not. And if you have a manual you will have no issue with streetability.
The cam might be rated from 4-8,500 k but thats just were it really starts taking advantage of its fill properties with a manual you could probably still take off around 1500-2000 and shift at 4 and drive down the street fine. Although not necessarily the best fuel economy for that set up the best would be lightest load possible to keep her in the rpm range of peak torque. So if you are worrying about fuel economy it will be fine if you have a stall matched to the torque curve despite higher revving.
#26
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All i can say is wow to all the people saying that you will start cracking stuff with these motors. The 406 i ran was a very streetable 10:1 motor that put down 514hp/564tq with no problems over the 4 years i ran it and then sold the car. I think alot of the ppl that had problems it probably came from bad machine work or something but i cant say for sure. My motor was done by Dyer Racing Engines and like i said...never any issues. If you want more info on that setup let me know 1fastirocz
#27
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564 with a 200 shot is pushing it. Its not machine work problem the siamese cylinders had heating and cooling issues they make most stock blocks worthless and can cause issues under high hp applications if not plumbed right and inadequate steam holes. The cylinder walls are also thinner to accomadate the larger bore.
564 tq will be fine alone but i question more.
564 tq will be fine alone but i question more.
#28
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Dont know it this helps but i run a stock 400 block filled to the bottom of the water pump holes. Cast eagle crank, h beam rods, je flattop pistons and old afr 227 heads. Ive sprayed it 475 hp in 2 kits quite a few times grudge racing.
Heres a video on radials and a 175 shot.
http://ywnv.vidiac.com/video/0915240...4100d4c886.htm
Heres a video on radials and a 175 shot.
http://ywnv.vidiac.com/video/0915240...4100d4c886.htm
#30
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It is ridiculous to say a 377 has heavier pistons because the bore size is the same and the rods will be the same size which has more affect on piston size than stroke length. You could even put 406 pistons in a 377 because its the same bore.
All i am saying is the 377 is a hell of an engine. Revs cleaner and faster, will rev higher and hold the rpms and will be alot more fun even on the street. Thats my next engine build is probably a 377 or a dart block destroked.
my dad has a 377 in his chevelle and it pumps out 750hp all motor and that thing screams it gets shifted at around 8000rpm
#31
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Dart M block will do you very well. That is why I want a 377 8000 rpm is no problem for it and they create so much power.
Thanks for the input I didn't think about shorter rods makes sense though since its pretty much a 327 crank. I just didn't see how the pistons would be that much heavier.
Thanks for the input I didn't think about shorter rods makes sense though since its pretty much a 327 crank. I just didn't see how the pistons would be that much heavier.
#33
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And to add to 97 birds information you can also buy pistons for a 377ci motor and use a 6'' rod. It also will help some of you out if you learn how to determine the proper comp. height for a piston. And to do this you take the stroke of a motor divide that in half then add in rod length take this # and subtract from 9 this will give you comp height.
377 comp height 3.48 divided by 2 = 1.74
1.74 + 6 rod length = 7.74
9'' deck height min 7.74 = 1.26 comp height piston.
Hope this helps i am not a good at explaning things.
377 comp height 3.48 divided by 2 = 1.74
1.74 + 6 rod length = 7.74
9'' deck height min 7.74 = 1.26 comp height piston.
Hope this helps i am not a good at explaning things.