I see alot of people running 355s with blowers, but ive always gone by the whole, no replacement for displacement theory, what is the reasoning by going with a smaller cube motor when these guys are rebuilding anyway? Im talking about blowers/forced induction specifically.

 

I believe the thinking goes along the lines of smaller motors needs less air allowing you to run smaller compressors. I'm sure someone else here can elaborate.

 

I will be going the 355 route mainly because it's difficult enough to try getting 450+ft lbs of torque to hook at the track. Adding big cubes, more boost and heads are only going to make it more difficult for me. Besides, these 355's out there run very well.

 

With a supercharger or a non-max'd out turbo, larger is better. However, the shorter compression height on a 383 and 396 piston makes it weaker due to thinner ring lands. In some rare cases, a smaller motor will make more power than a larger one, but only if you're max'ing out the turbocharger.

 

Things generally aren't so simple that they are decided on the basis of one issue. Having said that, there are broad trends:

1) 355: Common selection for people building forced induction engines above one atmoshphere. This tends to avoid ring-pack problems and issues with thin cylinder walls.

2) 383: Good all-around compromise for N/A or boosted engines under one atmosphere. Doesn't tend to get into clearance issues with the big end of the rod.

3) 396: Pain in the @$$ to build one because of clearance issues. Best to just buy one from Golen if you really want one. Probably not the best candidate for boost, although a mild nitrous shot (<100hp) would probably be fine.

 

ding ding.....this is why I went with a 355.....that..and its cheaper

 

IMO another reason for the 355 vs the 383, 396's for forced induction, could be that with either the 383, or the 396 you are going to add a bit more torque, plus with a blower you will also be adding a lot more torque, so some people could percieve not going with something that is adding torque on more torque. Plus as stated above, the 355's are cheaper, and will probably hold up a bit longer.

 

If you do it right, there should be no reliability/longevity issues between a 383 and a 355. Also, for drag racing, the extra torque from the 383 can be helpful to get the car moving before the blower starts making boost. A small shot of nitrous also helps.

 

Think about this: more cubes = more gas, poorer fuel economy. Gas is averaging $3.00+ a gallon, and in many places, that's for the cheap stuff. I'm not sure how much of a fuel savings you'd make, but I figure if you drove any of those engines RESPONSIBLY, you could still manage a respectable MPG with the 355...

 

Most people in this forum really aren't concerned very much with fuel economy.

 

I don't know what you consider this but... I got 14mpg driving highway and LOTS of traffic. Even romping it a few times.

I THINK I got 19 1/2 mpg once on the highway mostly... this is a 383 with a LE3 package too.

 

Does anyone have any FI numbers for the 355's fuel economy? I mean, if it's only by like 1 mpg, then I won't worry about it. What would be the advantage in going with the 355 over the 383 then?

 

I was getting about 25 mpg on the highway with my heads/cam/8# S trim 350 setup, 18 combined. Last year, I got 26 mpg with just the heads/cam when we went to G9. 760 mile round trip.

 

I am getting 23 on the highway with my NA 383. Assuming the cam I am having put in my motor currently isn't too far off from the one I have now, and as long as I keep away from romping on it with the new D1SC I would think I would still get about the same MPG.

 

I am getting about 24mpg on the highway with my blown/forged 350. Its not so much the cubes that will determine gas milege, but the size of the cam. I run a very small 214/222 blower grind.

Jason