383 vs. 400 for stroker block??

[Road_Runner]

OK, simple question.  How big a difference would there be to start with a 383 HP block vs a std 400 block as the basis for a stroker motor?  If I go with the 383, seems like the stroker options at .030 over are either 431 or something less than 496 CI (496 is what it is at .060 over).  For the 400, the same cranks yield 451 & 500 CI I believe.  I've read here and elsewhere that the valves can be shrouded a bit with the 383, but don't know how that impacts HP & performance in true numbers.  So is the difference here big & noticeable?  If you already had two 383 HP blocks, but could pick up a 400 block pretty cheaply is it worth it?  Part of me would like to just stay with the 383s I already have, but I don't want to ignore 'big' differences between the two options.

Thanks, Jim

[AMXguy]

Since 400 blocks are a dime a dozen I'd sell the 383 HP block to someone who could use it and use the 400 myself. they make a better stoker from what everyone says anyway.

[Road_Runner]

I'm doing the same thing with mine.  The #'s 383 will go into storage and a 400 will be used to build the stroker.  That is unless I decide to buy a Hemi instead. 

You have the same plan(s) as I do.  Ive actually got several pieces I've accumulated to put a hemi in and now I'm going back in forth.  So yeah, I'm definitely going with a stroker 383 or 400, unless of course I hold out for the stroker Hemi 

Later, Jim

[Chryco Psycho]

you are splittinghairs , either block will make a good stroker , you just lose 12 CI or so to the smaller bore 383
 I would stay with the 400/451 or the 383 /436 for street use but use the longer 440 rods

[Road_Runner]

you are splittinghairs , either block will make a good stroker , you just lose 12 CI or so to the smaller bore 383
 I would stay with the 400/451 or the 383 /436 for street use but use the longer 440 rods

Well that's what I more or less what I thought/hoped was true but I always read articles where the 400 is the 'way to go' on a B block stroker.  So who's stroker kit uses the longer 440 rods and who's doesn't?  I thought a 383 stroker with a 431/6/8 displacement all used the same length rods.  Guess I still have more to learn. 

Thanks, Jim

[Chryco Psycho]

the kits are available with either the shorter connecting rods from the 383 or the longer 6.76" long rods the 440 rod needs a shorter piston height reducing weight  which also removes weight from the crank so it revs faster . you can use a stroker kit or use crank & rods from a 440 but you have cut down the main journals to fit the smaller mains in the block .
the 440 source kits can be specified with rod length but most kits come with the 6.76 or longer rods , I wouldn`t go to the 500" 383 kit , the oil ring is over the piston pin & it is more of a race build , you won`t need the extra CI , the 451s make a ton of power !

[Cooter]

Remember the shorter the rod and longer the stroke, the worse the rod angle...You get much more below 1.52 and the engine isn't gonna make decent power cause it's using all of it's power to try and push the piston's out the side of the block....Just because the 383/400 will go out to 520 C.I., might not be the way to go due to this...


This the main problem with the brand X Furd 347 Stroker SB engine...They are coming apart...One rule when looking for Cubes is the bigger the block/bore, the better chance of a decent rod angle...Running the piston pin all up into the rings just because you wanted to run a 383 block instead of a 400, isn't the hot ticket IMO...

[Road_Runner]

the kits are available with either the shorter connecting rods from the 383 or the longer 6.76" long rods the 440 rod needs a shorter piston height reducing weight  which also removes weight from the crank so it revs faster . you can use a stroker kit or use crank & rods from a 440 but you have cut down the main journals to fit the smaller mains in the block .
the 440 source kits can be specified with rod length but most kits come with the 6.76 or longer rods , I wouldn`t go to the 500" 383 kit , the oil ring is over the piston pin & it is more of a race build , you won`t need the extra CI , the 451s make a ton of power !

Are 440Source's kits as good as any or are there others to check out before deciding?  North American made parts would be preferable to Chinese in my book although unless I can find other aluminum heads that I can 'hide' under orange paint I'm definitely going with a set of their stealth heads and have them checked out etc. before installing.

Thanks for the info, Jim

[Road_Runner]

Remember the shorter the rod and longer the stroke, the worse the rod angle...You get much more below 1.52 and the engine isn't gonna make decent power cause it's using all of it's power to try and push the piston's out the side of the block....Just because the 383/400 will go out to 520 C.I., might not be the way to go due to this...


This the main problem with the brand X Furd 347 Stroker SB engine...They are coming apart...One rule when looking for Cubes is the bigger the block/bore, the better chance of a decent rod angle...Running the piston pin all up into the rings just because you wanted to run a 383 block instead of a 400, isn't the hot ticket IMO...

At this point if I use the 383 block it will likely be a 431" at .030 over.  I figure I can make up the cubic inches elsewhere in the build and still end up with a stout street/strip motor especially since I'm also wanting to go with a 4.10 rear gear and some type of overdrive 4 or 5 speed.  Since I'm not willing to tub the car there's only so much power I can lay down off the line anyway.

Thanks, Jim

[Chryco Psycho]

everything is made in china , you would pay over 3000 for a US made steel stroker crank
440 source is not perfect but as long as your machinist checks everything they are fine , or just order pistons & have a 440 steel crank fitted by cutting down the main journals & balancing

[Road_Runner]

everything is made in china , you would pay over 3000 for a US made steel stroker crank
440 source is not perfect but as long as your machinist checks everything they are fine , or just order pistons & have a 440 steel crank fitted by cutting down the main journals & balancing

I won't say anything more about China, the whole subject depresses the heck out of me.  My #1 goal is longevity, I want the motor to hold up to the street/strip duty I have planned.  But I'd also like the 431 to rev like the 383 did so as I understand it the more 'bob?' weight I can remove from the rotating assembly the more rev happy it will be.  So should I just get the lightest 440 rods I can get that are also strong enough, do the same with the pistons, and then get the 440 crank balanced to match or is that basically what 440Source has already done and there's no benefit to piecing a 'kit' together myself?  Thanks for the advice.

Later, Jim

[Chryco Psycho]

the 440 source kit uses a light H beam rod & light piston all balanced as a kit with a new crank , the 431 should rev better than the 383 as it is a lighter rotating assy then a stock 383
 you could also piece together a kit using Manley rods & Diamond pistons & a reworked 440 crank but it will cost more

[Road_Runner]

the 440 source kit uses a light H beam rod & light piston all balanced as a kit with a new crank , the 431 should rev better than the 383 as it is a lighter rotating assy then a stock 383
 you could also piece together a kit using Manley rods & Diamond pistons & a reworked 440 crank but it will cost more

The main problem I have with 440Sources kit is the 431 even with the flatop piston along with normal combustion chamber heads yields high 9 - low 10:1 compression.  I'm looking for 11.00:1 so I don't know if I can find a head that will push the compression ratio to my target with the pistons in the kit.  Their Stealth heads have 80cc chambers which  based on their chart would yied around 9.9:1, and I'm not sure how close I could get having the heads milled a bit.  I wouldn't want to overdo this and have to mill my six pack intake to match.  Looks like if I can make 440Sources kit work though it will be my best option.

Thanks, Jim

[440mike]

we are doing a 383 to 431 stroker at work right now, it will be on the dyno within 2 weeks if you want to wait for the results ?

it is a 440 crank remachined to fit the 383 block, with eagle h beam rods, and diamond pistons with the stealth heads, flat tappet cam.

if u want i can ask him if it's ok to post up the dyno sheet when done ?
 

[Road_Runner]

we are doing a 383 to 431 stroker at work right now, it will be on the dyno within 2 weeks if you want to wait for the results ?

it is a 440 crank remachined to fit the 383 block, with eagle h beam rods, and diamond pistons with the stealth heads, flat tappet cam.

if u want i can ask him if it's ok to post up the dyno sheet when done ?

The more info you could share on the engine, the better!  I would really appreciate real world numbers, impressions on this combination.  I'd be very interested on the HP & TQ numbers and how they would compare to either  a similarly built 452, or 500+ c.i. 440 stroker.  Other than the block, there doesn't seem to be much difference price-wise on any of these combos unless its the fact that the RB stroker parts can even be cheaper than the same parts for B blocks sometimes.  Please do what you can to post whatever you can on this board.

Thanks, Jim