im planning on buying a shortblock and wanted to know if the price difference is worth it as far as power between a 383 and 396...using le2 heads and not sure on a cam yet but will more then likely get an le2 or le3 or something like that.

 

If you do a search, you will find a lot of discussion of this issue. My short answer is to go 383.

Rich

 

If your looking more for streetability go with a 383, i was informed from my builder that when you go with a 396 that the walls are much thinner and the generally dont last as long. As long as you have good heads you should make the power you want NA.

 

that walls are still the same size, its still a 4.030 bore. the only diffrance is a 3.875 crank over a 3.75, you need to clearance for the rods a little more but not a lot. the parts for a 396 start to get really expensive compared to a 383, if you got money the couple extra inches dont hurt. but its a big cost diffrance for the little bit more you will get out of it.

 

Okay I certainly don't want to hijack this thread but I've also been considering what stroker motor to build when my stock shortblock finally "gives up the ghost". One thing that is very related to the 383 vs 396 discussion is weather or not it is mandatory that all 396 stroker LT1's use a small base circle cam? I've seen several ads for 383 rotating assemblies that say due to the use of special "clearenced" rods in their package, that a regular base circle cam will work fine with their 383 assemblies. Every time I look at 396 shortblocks and/or rotating assembly packages nothing is ever mentioned about base cam circle requirements? Are they all assuming that a small base circle cam is required with all 396 LT1 strokers???

Finally, if you have to use a small base circle cam with a 396, I assume longer pushrods are also mandatory, but what about special lifters? The stock lifters will certainly work further down into the lifter bores on a small base circle cam, how will this affect hydralic lifter oiling? Are special small base circle cam lifters also required???

 

The issue in both cases is which rods are used, more of a problem with a 396. Two rods with excellent clearance are the Lunati "Pro Mod", which is an excellent mid-grade rod, and the Oliver billets at the higher end. No special lifter is needed.

Rich

 

ok guys thanks for the info...i guess ill just go with the 383 and maybe try one of the new edelbrock intakes. guess ill holla at bret about a cam. think ill be able to spray 200 safely?

 

Go with the 383. If you have plans to go further like a single plane, possible converted heads etc...I'd do the 396. I haven't seen any power differences with the stock intake and 383 or 396.

 

where are the big cost differences between the two?

 

the price of the crank rods and pistons, theres not to many people out there that make a good set up for a 396 and they all cost money, you can build a 383 for a little more than a 355, but a 396 is a lot more.

 

Interesting... the only real difference between the two rotating assemblies is the crank. You can use 5.7 or 6" rods. Just looked at Summit's site and the Eagle rotating assy. are extremely comperable in price. Lunati, albeit more expensive is also very comperable between the two cid's. Don't know what you guage as being real expensive, but the extra money may come from possibly having to resort to custom pistons depending on the size of your combustion chamber. If I remember correctly the custom pistons I am going to use were approx $200 more than the generic -5cc pistons and that's of course if you are already using heads for another application. If I would've gone w/ the "default" pistons w/ the Eagle kit the total would've been in the neighborhood of $1900... about the same price as the 383 kits sold from Summit. If you are building a complete engine from intake down then really the price difference is marginal. Machining wise there may be more clearencing involved, but again the price difference for that is not much more. Depends on the shop you use.

 

That advice is not entirely accurate. The cost for a LT1-based 383 and 396 *should* be the same. Some engine builders (if that’s what you call them) quote higher prices to build a 396 vs. a 383 based on some wild idea in their head. The only cost difference would be the extra labor to clearance the pan rail slightly more for the additional stroke (396), which is completely negligible. This is comparing apples to apples.

However, a person could be in the situation where if they went with a 396ci shortblock vs. a 383, they would be required to buy a custom piston to achieve a desired compression ratio based on the combustion chamber volume of the heads they are using. That instance would account for the 396 costing more. I think there are a lot of those type scenarios that account for people assuming that 396s cost more than 383s. You need to look at the whole picture.

Either choice is a good one. The 383 does have a more desirable rod/stroke ratio, but the 396 is a fine choice too

Jason

 

Yep,
They are pretty much the same costs parts wise unless the pistons are custom made. The only thing I would add is the cost of the oil pan. You can make a stock pan work with the 383 but a 396 would require a more expensive "stroker" pan. I suppose with enough banging and welding, you could get the stock pan to work with the 396 but you would have alot of time in that. Seriously though, if the stock intake is used along with an LT based head, the 383 is the way to go IMHO.

 

With the LE2 stuff, you're already going to be choking the 383. Makes no sense to go with a 396 when the 383 is already too much for that setup.

 

I had my 396 built for the exact same cost as what a 383 was going to cost me....I am using a standard base circle cam, stock oil pan (no major banging/welding), was going with a custom piston either way as I have 48cc combustion chambers, and was shooting for 12:1cr.

I agree you can make compareable power w/either....I just wanted the extra 13cid