When I went to my local machine shop to get my L48 block machined for a 383ci they looked at me and said why do I want to build a 383ci when I can build a 406ci cheaper and easier. I could not think of any reason why I would build a 383ci instead of a 406ci so I went with the 406ci and I am more than happy. It is cheaper to build because you don't have to clearance the block.

A couple of myths and misconceptions, 400ci motors don't run hot, mine never gets over 190 degs. And the other is the short rod thing, no one builds a HP 400ci based small block with a with a stock 400ci rod most are built with either a 5.7 in. or 6 in. rod.

The 406ci with the right heads and cam is great street motor, tons of torque down low and it still revs out no problem

 

I built a 400, but it got trashed by the machine shop. That being said, I don't have the time or energy to search for another 400 block especially when guys are wanting almost the same amount you can get an aftermarket block for. Anyway, a 383 is a good alternative, but after talking with Gkull and doing some research, I found another nice alternative---396 small block. I have all of the parts, but haven't started building it yet. I don't really think I'm going to miss the 10cubic inches I could have had with the 406. I also won't have to drill steam holes in my heads, or worry about the mains being strong enough. Trust me, I like the 406, but it's getting so hard to find a nice donor that the stress almost isn't worth it. As far as I know, all the 396 sbc cranks require 6 inch rods. I got a forged Eagle crank and 6" Eagle H-beams, but may switch to I-beams to keep block clearancing to a minimum.

Why build a stroker? Why would someone want alot of torque? Because it's fun... Isn't that the whole point of having a Corvette? If rpm's are so important, go get an old Porsche or VW. I'm not saying rpm's aren't important, but why do some people insist on saying that their way of thinking is the only acceptable idea? If I was that insecure with my ideas, I guess I'd talk down to everyone also.

 

Well heck...if you want a lot of tork and are scared of RPM, why fart around with gas engines at all??? Here ya go...

The Duramax Diesel 6600 has outstanding power and performance with targeted ratings of 300 horsepower at 3,100 rpm and 520 lb-ft of torque at 1,800 rpm.

Low RPM and LOTS of tork. What more could a tork lover ask for?



Dep

 

Big blocks do not have to get poor mileage. I regularly pull down 15 mpg.
By win on the street I mean I can easily pull 1200 rpm in 5th overdrive with 3.08 gearing and the motor is quite happy. 1550 at 60. The same 383 with 3.9 gears and the same overdrive transmission needs to be above 2000 to really run comfortable without chugging.
So in a legal situation on a secondary road doing the speed limit I am cruising at a quiet 1200 rpm in 5th and the motor is barely off an idle. The 383 can't even use 5th overdrive with his 390 gearing so he revs in the mid 2's and every time he shifts into high he drops 900 rpm into his dead zone.
I have a far more comfortable drive with less wear on me and motor.
As for a truck engine it is easy to get 400 horse out of a 460 motor, forget the 270 horse boat anchor.

This all started talking about building a 383 and I suggested that why not go for a 400 and forget the stroke. This didn't start about bigblock vs small block. This is about a big little block cheap to build vs a stroked 350.

 

Dep, have you seen diesel prices these days?

 

I just built a 383 and it was my first build. I have about 400 miles on it so far so I'm still in break in but the difference in the seat of the pants feel is amazing. My setup is a Eagle rotating assembly, Comp xe268 cam, Edelbrock performer rpm heads, Edelbrock performer intake, Stock carb And headers. In a couple of weeks I'm gonna take it to the strip. I do this a couple of times every summer last year I had 9.47 at 76 mph hopefully I'll be a little faster this year.

 

I see 383 short blocks with horsepower ratings anywhere from 330 to 500 horsepower, the only difference I can see in the specs are some have 5.75 rods and some have 6.0 rods. how can they calculate horsepower without knowing the cam or heads you will be using? some have the cam installed but still no specified heads, what gives,

 

Since we seem to be talking hypotheticals, why not just take and bore and stroke that 400 to 434 and really make some power. Big-block hp and torque with small-block weight. Or just go with a new LS2 or LS7. It all boils down to how much you are willing to spend and what YOU want the motor to do. Either way, sacrifices are made in the end and "stock" is boring.

KC

 

A short block should have no HP rating unless they say something like, rotating assembly good for 500HP or something like that, heil a short block won't even run so how you going to get any HP out of it

5.7 or 6 in rods make no difference in HP, some might disagree but I have never seen any proof of a HP gain for either rod.

 

Hey dep,

I with you on the LT-1 vette engine specs.
That was my goal with my 355. I've got the 2.02/1.6 heads, with 1.6 rockers, I'll have the lift (the duration will be different, but I bet the extra cubes of a 355 and headers and an x-pipe will make up for it)
I've definitely got enough power to turn the tires over as much as I want, and its a hoot to drive anywhere. I'll bet I can turn respectable quarter times with it, and I can rev it to 6500. Heck, reving a small block engine up over six grand is one of the finer things in life, and I have only 2000 into the complete engine rebuild.

trw

 

There ya go Ted. Ain't nothin wrong with those 5 extra cubes. And the heads sound good too. I'm with you about revving that smallblock. It's what they were MADE for for cripes sake. Build it right and revs will NEVER be a problem. From what I've priced, it takes a minimal amount of extra $$ to put in all forged parts. The price is so negligable that I wouldn't even THINK of installing cast parts.

Dep

 

Dep I right with you on this! Nothing like the sound of my small block at or near 7000 rpm, 427ci 4 inch stroker with full length 3 inch system. Small blocks are made to rev.

I do differ on the 355 ci motors. Not much quick revving ability in the top two gears. Heck I'm looking at Wipple chargers just so my car revs quicker in the top two gears.

 

You've obviously never heard a 8-71 blown big block under full load. The combination of the blower and the motor pulling it's heart out beats any small block.
Even my bigblock saw 7500 regularly when it was a nitrous motor.

 

Noral your 100% right. I have never heard the sound of sitting in the driver seat of running a blown big block through the gears. For that matter I probably never will.

I do think that when I go to a whipple charger and spread port heads with 2 1/8 headers that a 427 ci of small block will sound very simular.

 

I'll be running a very stiff 4-series rear gear with a 4-speed, so I'm not too worried about keeping the revs up. I watched that NASCAR race at Loudon, New Hampshire yesterday. Geez...cars running 8-9000 all day long. I know we can't get anywhere near the HP of a NASCAR motor, but I think we can approach their durability.

Dep

 

hehe

 

No change in my opinion. If I could get a NEW 396 ratmotor 4-bolt block, I wouldn't hesitate to build a 396/425 HP version and drop it in my car. Unfortunately, none are made by aftermarket makers

Dep

 

Come on Dep stroke it, you might like it.

 

For sure it will George but once you go that route you can never go back. My wife and I were outrunning a storm tonight and she didn't complain in the lease when I was running at 100 plus or really hoofing it from the stop signs. It looked like a tornado was comming. Made it home minutes before the storm unleashed.

George bet you $100 American that if you go the whipple route you will never regret it and what you have now will seem dead compared to what you will have.

 

Durability? One race. Ya, that's what I want. 400-500-600 miles then rebuild.