millis

I will post a thread to let you know how it turns out, course it probably won't be finished for a while.

I have read a magazine article, I lost the .pdf file, where the did the 400 w/ 327 crank. With an overbore it cam to 350. The article was called The 350 GM Should Have Built or something like that. It was very interesting, they used a really long connecting rod, something like 6.25" and could run crazy compression 13:1ish on 87 octane. Because of the rod to stroke ratio and large cam is how they got away with it. If you search hard enough, you could probably find it.

Then there is the 377ci (350 crank in 400 block) and my personal favorite 320ci (302 crank in 400 block). I would love to do a 320 but to much money.

At any rate, it is fun to bench race.
millis

Formula350

iTrader: (3)

Yea, I've known about the 377, but not the 320. 302 and 265 use the same stroke don't they? (Too lazy to load DesktopDyno lol).

Now that we know the babyLT1 has just a hair longer rods, that opens up the door for different combo's. As soon as I read that, I wondered if you could drop those in a stock LT1 w/o any issues. Probably an instant 355-360ci. Gah, now I have to open DD and see lol

Alright, here you have it.


And now to calc that extra stroke into a 350.... Oh my, those rods are much longer than I thought!! They add .240, so 3.720 total stroke in a 350 with them, making a 375cid :O Heck of a free stroke if you can find the rods. heh The 350, with the 3.000 crank, and those rods is a 326ci. Just .010 short of a real 327. Since I'm totally being a dork here, I might as well go the full extent. Small bore, HUGE stroke BabyLT1 block, with 350 crank and 6" rods makes for a 331ci. That 326 makes like 300/300, but 300hp from 5500-6000.

OK I'm done being a tard. If anyone wants DesktopDyno, send me a PM with your email.

GIZMO

iTrader: (8)

^^ Hate to burst your bubble, but that's not how it works. A 3" inch stroke is a 3" stroke regardless of rod length.

Formula350

iTrader: (3)

Teach me then :\

GIZMO

iTrader: (8)

It's quite simple. The piston travels the same distance either way. If you did use a 5.94" rod in a 350 ci motor you would have to order custom pistons. If you used the factory pistons that extra .24" that you were referring to would cause the piston to collide with the head. There is probably a good bit of debate on rod lengths in the advanced section, but that is a performance subject, not a displacement one.

Formula350

iTrader: (3)

Hmm, I always thought that you could go about a 383 2 ways. With a 350 crank and 6" rods, or a stroker/400 crank.

I guess my area of confusion is why they have/get different rod lengths, if they don't add to stroke or ci. Like, I can understand the rod's causing the pistons to mash the heads, but if you then get the offset/shallow pistons, that just negates putting in the rods in the first place :\

EDIT: After thinking about, and visualizing, how the rotating assembly works, it does make sense how rods don't effect stroke, but then I still am confused about what the purpose of longer ones are :S

millis

I couldnt tell you technically why longer rods give different performance. But I do know that what it changes is the time that a piston stays at the top of the engine for longer, because that is how the angles work out when you have a longer rod. This isn't really going to answer your questions, but you have to look at the mathematics of it and I simply don't remember. I just know that then end result is you typically want to have longer rods.

millis