SweetS10v8

I just officially aquired my 400sbc block, std bore, 2 bolt. I have to do all the machine work for a class in school : Bore, line bore, deck, splayed caps....etc

I am up in the air on what to officially do, in my heart says do a 434, but my head says stick with the 406. I am hesitant with the 434, as I have only done 350s and havent done any stroker motors, so maybe a plain 406 is in my future depending many things. I will purchace a rotating assembly consisting of 4340 Eagle crank, 6.0" rods, and srp pistons(what ci I dont know yet) This will have AFR heads, I love 195cc so any other head isnt a discussion, except maybe to go 210cc or 220cc.

I am building a longblock for now. I cant decide on FI or carb, I have always had carbs in the past. I would love to keep FI and go with a miniram, but I just dont know how to burn custom chips, Its a little intimidating to read about let alone trying it. That is what is pushing me to just throw on a 750 carb/victor jr. I already have a NOS cheater system sitting here

Anyone with experience building a 434 please chime in with problems you had during the buildup. I know I will most likly need a small base circle cam. Im realistic, I wont have the funds for a roller setup immediatly, so I will be going with a mechanical. Thinking 230s-240s Dur @.050, shouldnt be too wild in a 434/406. I ran a 248 in my 350, so Im guessing it will idle slighly better.

So any info or constructive critisims on buildups, cam choices, head sizes.......or even someone who burns chips would let me watch how to do it one day when they are already planning on doing it anyways.

This will be driven on the street as 2nd car, so kind of a nice day/ weekend cruzer, taken to the track 2 times a year if Im lucky.

ede

going to NBC? i had lot of friends went there.

fb305svs

stock with the 406.... thats just from what i have heard from people with 434's...

sounds liek you have a perfect plan their either way tho.

I say you might want to investigate 210cc heads.... i think your very borderline....

As for EFI, well i say if youhave the budget, go EFI, but carbs will always be cheaper, and tuning is a breeze.

However, i would probably suggest you stay far far away from minirams... we got FOUR, yes FOUR, that all had problems seealing to the intake ports of the heads... yes the casting and machine work was that horrid.... i personaly would think a stealth ram would be ideal!

five7kid

iTrader: (14)

Racer out here has an '89 Vette. He's gone hog-wild on this straight-line-race-only car, but some of his experiences apply to your questions, I think.

He started with a factory-block 412 (.030"-over, 3.80" stroke), miniram, AFR heads, 12.5:1 CR, back-halved, carbon-carbon front end (for reference), among other things. Shifted at 5800. 2nd season it cracked a cylinder wall.

The Motown block had just come out, he told the shop to get him a 434 shortblock. Something got cross-wise in the ordering/shipping, ended up a 406. Same heads and all, some small mods like different air ducting, he's running faster now the past couple of seasons than he did with the 412.

This past season, he was season champ in two race series (I was 6th in one of those), 2nd in another, and 12th in another (that I finished 2nd in). In the late Fall, he was running in 3 classes the same day, Saturday & Sunday each week. Hardly bothered erasing his dial-in.

Summary, that 406 runs hard, consistent, and long. The factory block couldn't handle the stress.

SweetS10v8

Whats the B stand for? I know it used to be just Northwestern college, now its UNOWoohoo, my own personal responce from five7kid, jk, you seem to know a lot and never go crazy saying you know it all, makes me very confident in the advise you give.

As I sit here and ponder, the 434 is almost just a bragging thing I guess, just to say i have it. It is more expencive, harder to build and is pushing the cylinder block to its limits, where as a 406 is what is supposed to be in the block. I would lean toward the AFR 210s with the 406.

Another thing I have been realizing is that it doesnt take crazy cams or compression to make power, I just want a 12 sec car I can drive around town. So Im thinking of flat tops.

Rods: I know I want 6" rods, but I am thinking of staying with I beams over H beams mainly because of the weight savings.

Nitrous: I have run a 200 shot on my forged piston, stock rod, stock forged crank 350 sbc without incident, so I should be able to run 150hp on this no problems, I hate assuming.

This came up today too, my Father has a set of vortec heads he ran on his race car he said I could use, I would still get the AFRs eventually but FREE is good! Those heads would just give me more compression and less flow, but I think they would work fine for cruzing town(yes he has the intake too, no i wouldnt buy the sdpc or whatever tpi intake, lol)

I too have pondered the Stealth ram, I dont know enough to make an educated desicion. More research is needed, keep the comments coming.

F-BIRD'88

Well the Vortecs will get you there no problem.
You can even port them and go up to larger 2.02 x1.60 valves.
You'd want to use a D dish piston to get the cr right thou. (vortecs are 64cc) Keep the CR right at 10:1

And if at a later date you want to switch to a set of AFR's you'll have no problems selling off the vortecs and intake.
But vortec will fit your performance goals and then some
and the $$$ is right.

For a 12sec or even a 11sec 406ci street motor like this a 6" connecting rod is totally unnessessary. Don't waste your $$$'s

This is a easy street motor. Does not need to rev high.
Peak HP will be at 6000 rpm or less.
There is no need to rev higher than 6500, ever.
With a 400ci street small block think torque and power,
not rpm.

Stock 5.7" GM "K" rods, cast 400 crank and block are more than up to the task. Even with a 150 hp Nos shot.
You can run high 10's with that.

A friend of mine makes over 700hp (1000 on NOS) with a stock GM 400 block and crank with Brodix 18deg heads. You need nothing more for 12's or 11's.

Good machining and assembly is all that is nessessary.
Get a set of KB D dish pistons and put the $$$ into heads.

You have some good choices for induction with the
Vortec heads. Performer RPM, Professional Products Crosswind or Hurricane intake.
For EFI you can use a GM RamJet efi intake like on crate motors or a Holley Commander EFI manifold for vortecs.
A RPM manifold could be used with a Holley Commander 4v throttle body EFI system too.
No chips to burn. Would run very sweet.

You're right a huge cam and high compression is not nessessary. A healthy Hyd cam and 10:1 will do nicely.

SweetS10v8

Am I off, or is this correct, I have been using compression calulators online and they all say that my .01 deck, .039 gaskets, 4.166 gasket bore, 4.155 bore, 3.76 stroke, and -5.0 cc flat tops will net me 11.4:1 with 64cc heads?? That might take out the possiblilty of those vortecs......I would go with a thicker gasket, but I want to keep quench at .040.

I want flat tops for good flame travel, but with 11.4:1 should I get some dished pistons?

edit: haha, you answered some of my questions while i was typing the question..

SweetS10v8

Your preaching to the chior, lol. I know heads is where the power is, thats why I will get another set of AFRs, and 2 of my friends have them after riding with me.

I always tell people a quote from Lingenfelter (I think):

Build a motor with the BEST cam in the world and ok heads and you wont make good power.... but build a motor with an ok cam and good heads and youll make good power.:hail:

F-BIRD'88

A D dish piston will have as good or better Flame travel.
The ideal combustion chamber shape is a ball with the plug in the middle.
On a Wedge head motor like a SBC a small(er) combustion chamber and a D dish piston models this best. A D cup 22cc piston like a KB168 with a 0 deck height gets the cr just right with 64cc heads on a 406.
10:1 A "Dcup" piston has just as much quench area on the top of the piston.

The stroke is 3.75"
If you build with too much compression even with aluminum heads you well need all the $$$ bottom end stuff $$$ cause detonation will be tearing up the motor
unless you use race gas. This is a street motor right? Over 11:1 is too much.

SweetS10v8

I think I found a good one to follow, this motor puts up some great numbers with a flat tappet hydraulic cam and 9.5:1 with AFR 180 heads even. Check it out.

I have gone back through almost 10 years of Chevy hi-performance and Super Chevy, and havent found one thats really that close to this one, and some of the other used roller cams. I even went as far as to plot out my own graph on excel, just to make sure I wasnt missing something.

what do you think of that buildup? Isnt it Ironic that I will will be getting those vortec heads at first then switching to AFRs again? lol, i found that funny.

Air_Adam

Little bigger overbore (0.040" i think) and you can really confuse people....

"My firebird has a 440"

SweetS10v8

std bore would be a 427

my friend built a 396 sbc and eveytime he would pop the hood to show someone they would say, "Your an idiot thats not a BB" :nono:

But Im sticking with the 406, maybe even a standard 400 if the taper is good and the bore is clean.