Im looking for an interesting motor to build out of an sbc. what is needed to make a 406? And is it better than a 383?

 

A 406 (typical 406) is built with a 400 block bored .030 over.

Better?

In my opinion, yes it is a better engine when built properly. One being that it has a larger bore. You need to use a longer rod though as the 400 uses a 5.565 rod length stock... too short for a good performance engine but that's not a problem with all the aftermarket choices.

The even better choice for a 1st gen engine is to build the 427. Using the same 4.125 bore block and a 4" stroke you get 427 cubes... 434 with a .030 overbore. You can buy the Bill Mitchell 427 short block assembly from Doug Herbert Performance for $4600. Then you just need some heads and you're well on your way to making a 600+ hp n/a motor that idles like a mild 383.

-Mindgame

 

Yea thats what I was thinking it was, I was hoping it wasnt though. I was kinda hopeing it was something done with a 4.00 bore block lol there alot easier to get a hold of than 400 blocks. What I think Im gonna do is build a motor the same as a 383 but .040 instead. That should make it like 385 I guess and I'll make it all roller and full float. Some people would argue .040 would give me overheating problems but my 305 is .040 over and it never goes over 200 degrees.

I was kinda looking for something different to build since there are so many 383s runnin around I like to be different. A 385 would be different enought I guess but I havent even got my block yet so Ill keep my eyes peeled for something that sounds good.

If you have any ideas post them. Ive also head of people making 396's strokers how do you do that?

 

The 396 uses a 3.875 stroke crank in a 4.03 block. So you need a forged crank as there were no 3.875 stroke OEM castings.

OK, we're starting to get into more questions here which is cool but You need to be more specific because we need to know what "gen" block you're referring to? When you say that alot of people are saying the blocks are too thin, what are you referring to? What gen blocks??
The new LT1 blocks may be a bit thin for large overbores but the new Goodwrench blocks (1st gen) will go 4.06 without much fuss. Alot of guys are using these blocks in their budget bracket engine builds right now. The old "010" blocks will generally go 4.06 too. As for the 400 blocks being scarce... I don't see that around here. Most guys are still afraid to run them, because they just don't know any better, lol.

As for being different... fugget it. No one is going to know the stroke of your crank when the thing's all together. Building the most popular engine combos is always cheaper. Almost as cheap to build a 383 as it is to build a 350 these days... especially if you stick with cast crankshafts.

-Mindgame

 

Im not sure of the "gen" division of blocks but I could easily get my hands on a older like a 327, or early 350. They are the better to use for building right?? Me and my dad are bulding a drag motor out of a 350 from an RV. Its one of the ones that are like 10% Tin 20% Nickel, I read those are good ones to build. But I want to build something myself to drop in the IROC in place of the 305. I kinda feel Ive reached the limits of its potential withought forced induction.

The 396 thing sounds really good, do you have to use an aftermarket block for that with a taller deck or can you use a 327 block or so like I was talking about. The crank thing doesnt really scare me that much, but what kinda rods do you have to have. I would imagine if you use a normal sbc block you would have to use shorter rods to use suck a long stroke. plz give me more info on this it sounds really good.

 

Ok, no offense Dart but these are "basic" engine questions and Fred may very well want to move this to another forum so let's be prepared for that. I'll continue to help you out with this regardless.

Keep in mind that there were two different 327 blocks, the small and large journal blocks. I'd just look for a 350 block and be done with it. Either that or go with a new GM block for ~$600. Before chucking that idea, consider the cost of finding a block, paying for the core, having it checked out and the machining. May be cheaper to buy a "good" ready-to-go block from the word "go".

All gen 1 OEM small blocks are 9.025 deck height (centerline of crank to deck surface). I personally would use a 6" rod, unless I was going to use a power adder, then I might just opt for a 5.7-5.85 center length rod. The rod and stroke length is going to determine the piston compression height (distance from wrist pin center to top of piston) so it all evens out in the end. What happens is the piston gets shorter... a good thing to some extent.
There are lots of pistons on the market for the 396 buildup so that's not a problem. Some of the less expensive pistons however are not available with the 3.875 stroke combo (KB for instance). So, plan this out before you start buying parts and have a realistic budget.

That should give you the basics for the bottom end stuff. There are literally tons of rod manufacturers out there making 6" rods. Prices go anywhere from $250-$2,000+.
Any other specific questions??

-Mindgame

 

LOL actually I know all that I was mostly confirming stuff I didnt mean to sound stupid; although I really dont know how the gens of engines are assorted. I was mostly concerned with clearance restraints with the 3.875 stroke crank, and if a combo like this is streetable. I have seen several pistones made specifically for 383 motors but never for a 396 (though i havent looked, this is the first time I have ever talked about one) The only other thing you said that confused me was "paying for the core of a block" Its probably just the way you worded it but it still confused me.

And I wasnt going to buy a small journal 327 if thats the block I ended up with. I would get a '68+ block.

 

Yeah, that was bad wording bro, sorry about that..... even confused me the second time I read it, lol.
What I'm trying to say there is that you have the outright cost for the block itself. Then you have to test it to make sure it's good and so on.

Clearancing for a 396 is not that much different from clearancing for a 383. May want to go with a smaller base circle cam and you may have to do a little notching here and there depending on the components you use.

As for the gens. The 1st gen blocks are self explanatory. The second gen block would be those built from 86 and up. Chevy went to the 1 piece rear main seal in 86 (different crank) along with a roller cam. Then there's the LT blocks which are different but are still called "gen 2" blocks by most people. The gen 3 is the LS1 and LS6 engines.

Are you planning to tackle the assembly work yourself or were you planning to have a builder do all of that?

-Mindgame

 

Nah the assemblys all me, the only thing that isnt going to be in my hands is the clearancing. I figure once I get everything together Ill take the block, pistons, rods, cam, and crank to a machine shop so he can clearance anything that needs to be and make sure everything will fit. Im guessing a 396 would be a crazy torque *****, even more so than the 383. Thanks for all your help bro, if you have any other side notes feel free to throw them in.

 

http://www.speedomotive.com/Stroker%20Crank%20Kits.htm
There is a link to alot of the combos you can build. There is even a stroker sale in the group purchase section right now (383 though). Mindgame is good to listen to. First thing you need to decide is how much money you have to throw at it.

 

Ok If I were to buy it all at once there is no way, Im a 19 year old college student, whose only in college cause he got a scholarship. So this is gonna be a gradual thing, it will take a while. Christmas presents, tax returns however I can get it lol . That being said money isnt all that much of an obstical because I dont plan on having it immediately.

The only place I may have to just settle is on the heads. I can get up the cash to buy the crank and rods at different times, but I dont know if I can build up $1000 for a set of aluminium heads. So I may get like a set of 75-76 vette heads casue they are easy to get and have the big 76cc chambers I believe. Then Ill have them ported, milled and have like 2.05-1.60 valves put in.

 

I'd encourage you to take a look at the Vortec heads if you want a really good head on a budget. About the best bang for the buck out there right now and they are superior to the older cylinder heads and considering the cost to rebuild a set of old heads.... they're a real bargain.
Scoggin Dickey sells a kit... assembled Vortec heads, gaskets, bolts, rocker arms and your choice of Edelbrock Performer or RPM Air-gap for anywhere from $729.95-940.95 (this from the 2002 Catalog). The price difference is due to the setup.... for "hydraulic roller cams up to .570" lift" the price is $914.95 (performer) or $940.95 (Air-gap).
Just throwing you some prices I've seen..... you may find better deals other places on the net so shop around. The Vortec would be my choice on a budget though.

-Mindgame

 

Alright I'll look into it, but its all just speculation at this point.

 

Yeah The Vortec heads are a great choice for you. If you can though get the best heads you can afford, the Vortecs are first on the list then something like the GMPP Fast Burn heads @ $1100 are killer.

A 383 with Scat Cast crank is a great way to go, you can do a pretty inexpensive stroker with that stuff.

A 400 would be just as cheap as far as parts, Scat crank and rods and a set of KB pistons. Just setting up the heads to run with the block is the only deal you'll have to go with.

A 406 (a 4.155 Bore with a 3.75" stroke) and a set of FastBurn heads would be a killer combo.

A good way to keep costs down is a Solid Flat tappet build up rather than a roller, the rollers always add costs.

Bret