93Z2871805

iTrader: (5)

Can some one answer me why go for a 355 rebuild over doing a 383 for the same (just about) cash? Now, I'm not talking about the guys going with the budget 355's reusing the factory crank and did the overbore while they were rebuilding or scored an aftermarket 3.48 crank for real dirt cheap. I'm talking guys who do all forged bottom end 355s when they could've spent the $25 extra on the stroker. I'm not cutting anyone down, I'm just curious to know. Like are some people road racing and need the revs? Are you running in a Stock Eliminator class that will only permit a .030 overbore and a stock stroke? You LSX guys doing the same can chime in (ie all AFTERMARKET forged 346s). Also, has anyone destroked the LTX's to like 302 or 327?

AChotrod

iTrader: (17)

Well the machining cost of the block is more, but if I were gonna do a fully forged bottom end it def would be 383 plus car.
With that said you could make a 355 fly and might be better for a High boost FI or spray car since there isnt any additional block material to be removed.

93Z2871805

iTrader: (5)

Well in all fairness, when I did my 383 I had to break out the grinder and clearance all 8 cylinders for the bigger stroke. But that was free, the machine cost would have been the same either way.

myltwon

iTrader: (1)

355 is worthwhile if you reuse stock rods and crank. if you're buying all new the only cost difference is clearancing the block and you can even do it yourself which I did

stevo9389

true story but that oil pan "clearancing" was just a bit ghey

myltwon

iTrader: (1)

lol yes it was especially the 2nd time around

skinnies

iTrader: (33)

I'll be building another 355, using the stock crank as I know it is plenty strong for anything I plan to do(sub 900 crank HP).

96LT1355Z28

iTrader: (2)

X2, Depending on the top end they both have the same power potential. I'd rather save the $ spent on a forged crank and put it into the top end.

Colin91Z

iTrader: (9)

x3

I'm already planning my next LT1 build, it'll be a 355 with FI this time

SS RRR

iTrader: (2)

Only real advantage to more CID is low end torque, which is great for an all around street/strip car to where the driver does not want a lot of gear and would rather produce good power using lower rpm.

AChotrod

iTrader: (17)

This is exactly why I would go bigger If i was going fulley forged.
If I ever decided on turbos, it would be a 355

93Z2871805

iTrader: (5)

Well what I couldn't get is when you want more revs? Why shorten the parts fatigue life with higher rpms? Just because you have a 383 does not mean you CAN'T rev it to 7,500 just like a 355, just means you don't HAVE to.

GIZMO

iTrader: (8)

Not true. With matched heads and cam you would also have a big HP advantage.

22lambo

iTrader: (1)

So you guys are saying if you want to have boost it would be better to go with the 355 over the 383? What do you consider high boost and can the stock crank really support more than 900 HP?

ls2pontiac

iTrader: (1)

If you are putting out over 500 crank hp, or close to it..why not go with a forged crank? from Ohio Crankshaft they are like $480. if u are already spending a ton of money on everything else, another 5 bills shouldn't hurt

skinnies

iTrader: (33)

Why not put that money toward something else if you aren't planning on making that much hp. The reason I said sub 900 crank hp is because I made just shy of 900 crank hp on my stock crank and I know others have sprayed 300 shots and made A LOT of power, not to mention all the turbo guys making insane power. The stock crank is a lot stronger than people give it, hell how many times have you ever heard of a stock crank breaking?

SS RRR

iTrader: (2)

Depends on the RPM levels and CID comparison. I don't believe for a second there is a real high end hp advantage between a 350 to 400 small block.

Schweet97Z

iTrader: (35)

how many HP is the stock crank good for?

quik95lt1

iTrader: (7)

I agree with GIZMO. More cubes = more air in the cylinder = more power!!! A 383 will make way more midrange torque becuase of the extra stroke and it will absolutly make more top end power with that 30 extra cubes. The myth of a 383+ not making top end power was created by big cube motors with not enough air flow or cam. Sure if you build a 383 with stock heads, you will have a stump puller, but put some airflow and cam to it and you can have a high rpm monster! I'm a 385c.i. with AI 215cc CNC TFS heads that flow over 300cfm and a big solid roller that I drive on the street and I peak at 7400 and make usable power to 7800. So 383's will make top end power as long as you can move the air.

And to prove it here is a video of the car on the dyno and the graph back when I was fighting my ignition problems.
http://www.youtube.com/watch?v=eiT0lLlGcvw

SS RRR

iTrader: (2)

Cylinder heads are a limiting factor. Ron Hutter has built small blocks with a 363cid that have made over 900hp at 8500 to 9000rpm.