Thread: chevy 400 build help

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I am building a 400 small block two bolt main. the block is bored .30 and i am using vortec heads. I need the pistons at about 9:1, but i want to build the engine where it is quick out of the hole. any suggest on pistons crank cam would be very helpful. I was to run regular gas not racing gas. But I want the torque power out of the hole. engine is going in a 1970 c-10 pickup 2wd with 3:73 gear.

quick throttle response nice clean quick take off! do you understand now?

Hey Denny, I have a bunch of those print outs for the wall with the circle on them that says, "Bang head here".......Want me to ship some to ya?!?!?!?!?

Just be sure to place them on the drywall not hard wood or metal.....

Nothing like a new guy that turns to us for help because he is "cluless" and then he is a smart a$$.
Let me guess.
He is 19 still living at home with mommy and daddy.
I think he might be a little wet behind the ears yet.

A little wet is putting it mildly Erik.

For the benefit of others who may be reading this thread, I'll weigh in with some thoughts.

If I'm understanding the chevy406 correctly, he is wanting to build a low-rpm tractor motor to move a heavy pickup truck.

I agree with the choice of Vortec heads for this application due to the rather smallish intake ports (170 cc's) and their propensity to keep mixture speed up in a larger motor to aid in cylinder filling at low rpm's. I would not recommend these small heads for a 406 that will be revved higher, because in my opinion they will sign off at around 4,500-4,800 rpm's. Erik would have a better handle on the top limit of these heads on a large small block, I'm just estimating for the sake of this thread.

If the heads are going to sign off early, then it makes sense to keep the static compression low (around 9:1) so you can use a shorter cam with an operating range of idle to 4,500 rpm's in order to screw together a balanced package that will pull tree stumps.

Although the Vortec's work best with a flat-top piston, that will not be possible with a 406. You just can't make a 9:1 406 with flat-tops and that many cubic inches with 64 cc heads, so dished pistons will have to be used.

Keith Black makes a 30 cc dish piston using a 5.7" rod that would work for this combination, part# KB126 and would put static compression ratio at 9.1:1
You'll have to do the normal clearancing at the cam/rod bolt heads, pan/rod big end, and pin-end balance pad/underside of piston crown with the 5.7" rods, just like you would for a 5.7" 383. Or, purchase a reduced-base circle cam to side-step the rod bolt grinding.

NEVER TAKE THE WORD OF ANYONE ON ANY FORUM TO MAKE YOUR FINAL CHOICE OF CAMSHAFT FOR ANY MOTOR FOR ANY REASON. ALWAYS TALK ON THE PHONE WITH THE TECHNICAL PERSON AT YOUR FAVORITE CAM GRINDER.
Now, with that having been said, it's ok to listen to some of the professionals and well-versed amateurs on this and other forums in their advice on cam selection to get you close to what you should need and to tell you why. Like I said, I would choose a short hydraulic roller cam for this combination, maybe something like the CompCams 270HR grind. Operating range 1,800 to 5,000, 270* duration @ advertised, 215* duration @ 0.050" tappet lift, 0.500" theoretical valve lift with 1.5 rockers and ground on a LSA of 110*. Although this cam looks slightly large for the application, this is a LARGE small block and the cam will appear slightly smaller to the motor than it would look to a 350 motor. This cam will require a different spring/retainer combination on the heads. Stock Vortecs (GM 12558060) are limited to 0.450" lift as is. Scoggin-Dickey Chevrolet produces modified heads to use with higher lift cams.
www.sdpc2000.com

To put the icing on the cake, I'd use a slightly looser converter, something around 2,000-2,200 stall to help get the motor up on the cam earlier:

From Hughes website:
"Street Rod 2000-2200
This converter was designed and manufactured for the street rod enthusiast needing that slight edge over the O.E.M stock converter. This unit has silicon brazing for strength, needle bearings for reliability, and stator modifications for more torque multiplication."

To The Ones I Offended With My Post Please Except My Apolige , I Didn't Mean Anything By It. This Truck With This 400 Small Block Will Be Driven On The Street, Not A Track Or Drag Strip. I Just Wanted To Have Some Insight On What Would Be A Good Strong Build For This Engine And Still Run Pump Gas.

Also I Forgot To Mention The Tranny Is Th350 Truck Is Geared 373 , All I Want Is Go Strong Power . Any Advice Would Be Helpful.

Originally Posted by erik erikson

Nothing like a new guy that turns to us for help because he is "cluless" and then he is a smart a$$.
Let me guess.
He is 19 still living at home with mommy and daddy.
I think he might be a little wet behind the ears yet.

What need is there to publicly voice assumptions and insults like this?

If you are here to help, at least make a veiled attempt at doing so instead of first jumping down their throat. I am not TRYING to single you out, but yours was the sharpest needle in the bunch. If you have the knowledge (which many say you do), then share and engage in discussion and/or debate. If the discussion goes nowhere, end your part in the discussion. It's that easy.

Thanks Tech for staying on track.

Sometimes You Have To Choose Your Words Very Carefull , Since You Really Don't Know How The Person On The Other End Of The Conversation Will Take It. Thanks To The One That Tried To Help And To The Rest Thanks For Looking At The Post Which Will Be My Last On This Message Board. God Speed

Thanks for the responce and hope I'll be forgiven. The engine I want to put together is a 400 chevy small block bored 30 over. I will be running cast 64cc votec heads and a th350 tranny with a rearend gear of 373. This engine will also have a 650 holley carb. This engine is going in a 1970 C-10 2wd truck automatic. I would like for this engine to have awesome torque and good horsepower. I am looking for the truck to be quick from stoplight to stoplight in a matter of speaking. But I still want to be able to run pump gas in the truck and not have to use racing gas. I would like info on building the block I just have the block, need to know pistons , cam and all compnets to make this engine hum from stoplight to stoplight. Hope this is enough info on my engine. I am new to engine building and don't really know alot, I guess you could say I am soaked behind the ears. That is the main reason I posted the question on this forum was to get help and advice from people that would know how to tell me to build the engine, so I could get out of the engine what I wanted. I posted for help and advice and to learn a thing or two about building a 400 small block. I learned I have to be alittle more open minded in reference to other people's comments. Now if anyone could help me put this engine where I want it I will be greatful. God Speed

Originally Posted by DennyW

...Some times there is need. Does this mean if we are in a building, talking, that no one would voice their open thoughts ? Would you write a note, like in school, and pass it to each other, or wait till they leave, and then talk about them ?? This is a club, a gathering. Joking, and mild comments are common. I took it as a teasing thing myself.

I have to respectfully disagree with you Denny . Calling someone "clueless", a "smartas$$", and "living with mommy and daddy", is not joking. To somone you just met, that's insulting. Maybe not amongst "regulars" where people know each other's writing style but this person is not a "regular" (yet...looks like will be though ) and nobody took the time to figure out whether a) he IS being a smarta$$ (which he wasn't), or b)just doesnt know how to express himself on a forum with smily faces and the like.

BTW: You are about the dullest needle in the bunch (NOT the dullest POSTER). You have a great writing style (maybe stems from the 10,000 posts worth of practice you have). Cheers.

Let's press on with this engine because I love 400 SBC's...

Tire size 15 in rims and would like to get out as cheap as possible. I would say around $1000.00 or so think I can do pretty good with that figure?

what do you mean by 2nd to 3rd stage cam? Mid to high rpm performance?