You'll be happy with a 383.



I dropped this into my 68 convertible, along with a TKO600 and 3.7 diff gears...
I can't stop grinning everytime I fire it up and go for a drive...
and it's been in for 3 years now.

 

OP,

Go the 400 SBC route. I've never understood the 383 obsession when you can get an extra 20 or so cubes for essentially the same $. There's a few tricks to putting one together though.

A well put together 400 with a good set of heads will clobber the stock 427/454 crowd.

 

There is no substitute.................

 

I thought that when you can't go any bigger than a 383 on a standard SBC block. If you do, you have to upgrade the block to a bowtie or dart block (which means big $$). Because the cylinder walls get too thin. Maybe I misunderstood?

 

You're correct htown81vette. The 400 blocks are starting to become less common.

If you want you can use the existing 350 block and bore it .030 over and the add a 400 crank & rods to get 383. The crank and rods is what makes it a "Stroker". This is where the budget 383 sort of got started.

 

I have a friend who built a 408 ci Small block with an injected Whipple supercharger in his Vette. I don't recommend 4 inch stroker cranks in stock blocks. You end up partially filling the lower water jackets with epoxy. I have built several 4.030 X 3.875 stroke for @ 396 ci. Recently I built a 4.125 X 3.875 for 415 ci.

 

Many times for articles 383s are made from new blocks so .030 over. Many have been made .040 over for 385. Some have bored out more.

The 3.75” BB stroke (396, 427) transforms the SB more than would be expected & adding +10% C.I.

 

Which block did you use for the 415 build?

 

So would a well put together 327.

 

You could use stock 400 blocks. In the past i've built a 421 ci. but i chose to use a Dart with the 415 build. IMO you are better off if building a Gen 1 sbc to just go with a stronger block with the better revised oiling system. The cylinders are so thick that it can take big over bores. I think the Dart SHP block can take a 4.185 bore. My 434 ci Motown can take 4.200 for up around 460 ci

The real problem with all the *** Kicking motors is that it constantly on your mind what is going to break next.

 

Yes, depending on how well put together, most stock BB's...

 

"I don't recommend 4 inch stroker cranks in stock blocks. You end up partially filling the lower water jackets with epoxy."

I don't understand this. Would you please explain to a novice.
Thanks.

 

by increasing the stroke of the crank, you need to clearance the block. you do that by grinding away the points were the connecting rods touch it. this usually will cause you to grind into the lower water jackets, with a large stroke like 4.00". on stock 350 blocks 3.75 stroke or even 3.85 stroke is about max.

 

Thanks. No way I would want to breach the water jacket. Not worth the risk of the epoxy failing / leaking coolant.

 

Not to go OT, but if you get to the point where you're putting Hard Blok into the block...you should be looking at an aftermarket block that can handle the stroke, and will have other features like a raised cam tunnel.

Interesting debate across the board

 

That is a NICE looking engine. Can't wait to see pictures of it installed.

 

To the OP, a fast street car is relative. I have a 64 Impala SS with a 350, flat top pistons, 462 Double Hump 2.02 heads, Performer RPM intake, 600 Holley, mild hydraulic cam, and 1 5/8" headers into 2.5" true dual pipes. A mild build. A lot of people I give rides to in this car think it is very fast. To me it feels like a slug. My Corvette terrifies them. Traction on the street is a real problem for the Vette too.

If you would be happy with 400 hp a 383 or a 406 can do this with a very mild build that will run on regular gas, 450 to 550 hp on Premium (you can make more but they get a little less friendly on the street). Your 350 can make 400 hp built and still be very street friendly. That would be your cheapest way to go, but it's not really that much more for a 383 or a 406 if you can find a good 400 to build.

 

Sounds like building the Dart SHP might be the ticket. it has a lot of flexibility on what I can do with it, meaning how much do I want to spend. Reliability is a very big issue for me, I only want to do this once and enjoy it.

 

If this is the route you want to go, you'll spend a little more, but you will have the reliability & strength you're looking for.

I just finished a Dart SHP, have a look at the thread "Dyno Day!" The motor itself, even at that level of build was rea$onable.

 

For what it's worth, I think the aspect often missed is not only how much power, but how often and to what durations will you be spinning your motor to make this power. I just did the Dart SHP route for my 400. I opted to maintain 5.7" rods, stock 4.125 bore, and 3.75 stroke because it's a street car and I wanted to make great power yet leave some on the table, in the interest of reliability, simplicity, ease of maintenance and longevity. Here are some tips passed on by my shortblock builder. > 5.7 rods keep all piston rings out of the pin area, like factory engineering; 4.125 bore allows more rebuild opportunities; > 3.75 stroke can lead to minor costs like oil pan selection but the selling point here was that it would require clearancing con-rod big end bolts and/or a smaller base circle cam (at least in the SHP and, as far as I know, factory blocks) To each his own, but I chose a compromise.

The SPH is approx $1500, but is basically ready to go minus final hone so factor in any machining required for a rebuild as it will offset this a bit. The primary oiling aspect is really cool, but I don't think necessary unless building a racer. The heavier cylinder are casting and improved water jackets are really only significant improvements over the factory 400ci design. Most of the research I did indicated that one of the greatest design attributes of the sbc was its oiling/cooling capability.

I would look at a factory roller 350 block for either a 350 or 383. If money permits, I would look at SHP or GMPP for a 400. Perhaps a power adder on a stout 350? If your goals are greater, look at the bigger Darts or Motown.

r,
Rob