Hello have a question and trying to get an understanding, I currently have a 355 sbc maybe 10k or less miles with AFR 190 heads and was thinking about adding a “400” crank to it along with the 400 balancer & fly wheel while I have the engine out for painting the car. I read on some forms where people just get the stock 400 crank machined to fit the 350 block and still used the 350 rods (short rod 383) however I have dome top pistons and was curious if this method would still work while using them. I also seen some reply and say just to buy a aftermarket 383 crank what would be the difference, ***uming I’d still have to get the 383 crank machined to fit the block but would going this route still be similar to buying a stock new crank.
350 pistons wont work with a 400 crank. A 383 stroker crank doesn't need to be machined. The pin height on 350 pistons doesn't work with the stroker crank either. There are many crank ,rod , piston configurations to choose from. GENERALLY , you're better off financially & compatibility wise to get a " kit" , compe***ion products ,skip white , etc have good prices / quality ...
Back when I was racing, the hot setup was to get a 400 block and put a 350 crank and rods in it. You ended up with about 370 cu in and no balance problems. You did have to buy a special set of main bearings to accommodate the smaller main journals. The nice part is that you could get a forged crank and the good 350 pink rods direct from Chevrolet at reasonable prices.
Or if your machine shop is good, you can have the 400 line bored and honed to the tight side of a 350s main bore so that the 350 main bearings snap into the bored/honed 400 main bearings. You also had to remove the thrust bearings from the 400 rear main, and cut notches for the bearing tangs. You now have really good fitting bearing spacers that mean you don't have to keepgetting the special bearings for refreshes. Oh, and some people recommended pinning the 400 shells with roll pins to keep them from spinning. Absolutely required??? I think that depends...
If you use an aftermarket crank, you can get them in 350 main journal size. Some aftermarket cranks are also internally balanced so you can use a 350 balancer and flywheel. If you want to keep your 350 pistons then use shorter 400 rods which are 5.565" long [0.135" shorter to allow for the extra 0.135" crank throw]
I have never understood the infatuation there seems to be for the 383. I, like jaracer mentioned above, have always been drawn to the 377 (400 block/350 stroke crank) but they never seem to get much mention. Maybe I'm just a short-stroke sorta guy. (Let the jokes begin) Lynn
And if your displacement limited, a 302 crank make a 348 ish sized engine with a 400 block. Rev City!
383 will have more torque, just buy a rotating ***y, a **** or Eagle cast rotating ***y isn't that high. I'd avoid the KB pistons and I'd go internal on the balancing. Look up Skip White and look at his prices.
Better still a 0.030 over 400 block with an aftermarket steel 400 crank and 6" Rods [the oval track boys have proven the reliability of this combo] But this thread the OP is wanting more cubes while still using what he already owns.
We've been conditioned to believe bigger is better . In the case of 350vs 383 and if you like torque ( who doesnt) the 383 is definitely better , IME
Finding a good 400 block now a days is hard, although it seems the older 350 blocks are getting scarce also.
I had guys tell me that, but TRW already had the correct bearings so I went that way. I was really happy with that engine.
Thanks! Will have to review my options then and see what will work best. Figured I’d ask due to all the mixed articles I was reading and then faintly remembering people making them with the bare minimum lol
Nice! My grandpa was telling me a little about that! personally I’d love to find a 400 but here in Washington it’s so rare to find one for sell even a bare block.
This ok perfect this is exactly what I was looking for and interested in learning more on. With the shorter 400 rods it will Thank you! This is exactly what I was looking for. Going this route will I still have to do some work around the oil pan issues or the camshaft issues with anything hitting? Sorry if that question is hard to follow lol still learning.
If I could find one local I’d love to build one! seen and heard some good builds with 400s maybe my next car I’ll order a short block. LOL!! With the joke.
True true, I will look into those brands ! Appreciate it. Defiantly got to keep in mind that I wouldn’t want to be rebuilding anytime soon LOL
Yes that’s exactly what I want to do. if I could find a 400 to build I would jump on it in a heartbeat.
this is true. And yeah I defiantly want more out of it so I was thinking if I could figure out how the older 383s were put together it would be a good route to go.
Very very rare! Specially here and if I could I would grab and build one without a doubt lol but yes also true about the 350s
You will still need to clearance the block, but when using 400 rods there is no camshaft issues The 400 and the 350 [and all SBC's] use the same timing chain so the cam is the same distance from the crank centreline. 400 rods are shaped to clear the camshaft
Using 6" rods gives you a better bore/ stroke ratio & the ability to use an internal balance crank without expensive Mallory metal .You can buy a new 350 block reasonably. Can't say the same for a 400 .
I think there are 5 or 6 different timing covers that fit a small block, all with different timing marks
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