Thread: SBC build ideas.

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I know I have tried to start off my first build too complicated.
I need to get down to basics and realistic goals for my first SBC build and I need to organize a set list, a calculated process to begin my build.

Firstly, just chose a displacement already, as I have a 350 on hand, this will be my choice.

Secondly, my expectations and goals for performance... I honestly believe 1RWHP/CI naturally aspirated, streetably, reliably, and on pump gas should be reasonable and within my capability.

So now that that is established I need the forums help.

The most important thing for me to do would be to identify all the components of my core, and then decide what gets replaced and what stays stock right? Correct my logic here if I'm wrong. 350RWHP on a chevy 350 with an auto 4 speed turbo trans to a 12-bolt posi-trac diff (can't remember gearing) is possible on some of the stock internals while staying within my expectations no?

I need to: Identify the heads. The valve train. The current bore shape and weather it needs to be overbored. The piston types. The rod types. The crank type.

Give me more homework here, I'd really like to get the ball rolling.

Originally Posted by nfswift

I know I have tried to start off my first build too complicated.
I need to get down to basics and realistic goals for my first SBC build and I need to organize a set list, a calculated process to begin my build.

Firstly, just chose a displacement already, as I have a 350 on hand, this will be my choice.

Secondly, my expectations and goals for performance... I honestly believe 1RWHP/CI naturally aspirated, streetably, reliably, and on pump gas should be reasonable and within my capability.

So now that that is established I need the forums help.

The most important thing for me to do would be to identify all the components of my core, and then decide what gets replaced and what stays stock right? Correct my logic here if I'm wrong. 350RWHP on a chevy 350 with an auto 4 speed turbo trans to a 12-bolt posi-trac diff (can't remember gearing) is possible on some of the stock internals while staying within my expectations no?

I need to: Identify the heads. The valve train. The current bore shape and weather it needs to be overbored. The piston types. The rod types. The crank type.

Give me more homework here, I'd really like to get the ball rolling.

I would guess you know the 350 can be made into a 383 by a crank and piston change.
The 350 RWHP is about 400 or so at the crank.
By 4-speed do you mean a 700 r4?
If you mean a turbo tranny it is a 350 or 400.
Yes,your 12 bolt will handle 350 RWHP.
Find out your gear ratio.
The casting numbers can be found on the heads under the valve covers.
Stock rods will work fine as long as they are prepped well.
You know that you will get about 25 + ideas of what to do.

Yes, familar with both stroking and destroking SBCs.

I am starting on a standard bore/stroke and working with bolt-ons for the sake of educating myself.

350RWHP is pretty much achievable without doing anything drastic I'd imagine?

As for the tranny, all I know is it is the "turbo" 4 speed trans that came with a 5.7L Chevy G30 work van with a 1 tonne (I THINK) 12 bolt posi rear end. Like I said, still gotta find out the gearing and the rest of the block info, havn't cracked open the valve covers yet. There are NO numbers cast on the exterior?

I am trying to get this build done reliably, but also on the cheap, and preferably without altering the short-block at all.

Financially there is a very big difference between a properly done 383 build and just beefing up a 350 with bolt-ons and some new internals. But would you say pushing the 5.7L to 350RWHP N/A is practical on less than a large budget? 3-3.5 thousand tops?

Originally Posted by nfswift

Yes, familar with both stroking and destroking SBCs.

I am starting on a standard bore/stroke and working with bolt-ons for the sake of educating myself.

350RWHP is pretty much achievable without doing anything drastic I'd imagine?

As for the tranny, all I know is it is the "turbo" 4 speed trans that came with a 5.7L Chevy G30 work van with a 1 tonne (I THINK) 12 bolt posi rear end. Like I said, still gotta find out the gearing and the rest of the block info, havn't cracked open the valve covers yet. There are NO numbers cast on the exterior?

I am trying to get this build done reliably, but also on the cheap, and preferably without altering the short-block at all.

Financially there is a very big difference between a properly done 383 build and just beefing up a 350 with bolt-ons and some new internals. But would you say pushing the 5.7L to 350RWHP N/A is practical on less than a large budget? 3-3.5 thousand tops?

Yes,3.0 to 3.5.
$3,500 will get you a 450 hp 350 easily.
The long block anyway.

That's good to hear. A bolt-on only 350 would make close to the power I want but to get it all the way there it will probably just need an entirely new top end no? Aftermarket heads, new cam, intake and carb...

Bow Tie Iron Vortecs always caught my attention? Will a pair of used double humps flow up to 350 WHP? I'm going for cost efficient here, as any budget I save on will go to other parts needed for the car.

Cheap, but sturdy, and 350WHP. I just want something for the street with a bit more go than average "quick" cars that I can wind out on the strip for an ok timeslip a few times a year.

Originally Posted by nfswift

That's good to hear. A bolt-on only 350 would make close to the power I want but to get it all the way there it will probably just need an entirely new top end no? Aftermarket heads, new cam, intake and carb...

Bow Tie Iron Vortecs always caught my attention? Will a pair of used double humps flow up to 350 WHP? I'm going for cost efficient here, as any budget I save on will go to other parts needed for the car.

Cheap, but sturdy, and 350WHP. I just want something for the street with a bit more go than average "quick" cars that I can wind out on the strip for an ok timeslip a few times a year.

The only problem with the double hump heads they are 30+ years old.
I.M.O.,I would not put a lot of money in to them.
If you are looking at Vortec heads also look at Dart Iron Eagle,Worls S/R Torquer.
I would also look at the imported aluminum heads these can be found bare in the $500 area.
Happy Thanksgiving.

All my requirements for heads would be good breathing through till redline and supporting up to 400HP, pretty much, which the Vortec irons are quoted to do precisely.

If there are alum heads out there for a similar price then I might consider those too, but Vortec irons seem pretty dirt cheap. Aren't Dart heads pretty pricey? I'll go for used heads if I need to, I'd just make sure they aren't over-warped and have the entire block decked for a fresh start.

I'm looking for snappy throttle response and torque-happy hard acceleration in the finished final product. Preferably without having it flat out die in the upper RPMs, I know I can't have everything but...

Not sure about the cam selection still...

Originally Posted by nfswift

All my requirements for heads would be good breathing through till redline and supporting up to 400HP, pretty much, which the Vortec irons are quoted to do precisely.

If there are alum heads out there for a similar price then I might consider those too, but Vortec irons seem pretty dirt cheap. Aren't Dart heads pretty pricey? I'll go for used heads if I need to, I'd just make sure they aren't over-warped and have the entire block decked for a fresh start.

I'm looking for snappy throttle response and torque-happy hard acceleration in the finished final product. Preferably without having it flat out die in the upper RPMs, I know I can't have everything but...

Not sure about the cam selection still...

The Dart Iron Eagle S/S 165 cc port head can be picked up for around $700 to $750 complete.

Yea, my mistake, they are pretty cheap, what kinda numbers do they flow? Rougly what HP ceiling? I suppose it's a draw between these and Vortecs bang for buck...

Originally Posted by nfswift

Yea, my mistake, they are pretty cheap, what kinda numbers do they flow? Rougly what HP ceiling? I suppose it's a draw between these and Vortecs bang for buck...

The Dart Iron Eagle heads flow well enough to support.450 at the crank.
Becareful when you look at the Vortec heads.
Some of the Vortec's will only let you run a .450 cam and they will not be machined for guide plates.
There is a head that comes with springs good to .525 lift and machined for guide plates.

have a lok at pro topline heads made by RHS, they get a lot of good write ups and are cheaper than some of the other manufacturers. outflow a lot of the other more expensive heads.

http://www.ryanscarpage.50megs.com/combos2.html

I found this site a while back, it has many different combos on proven dyno's
great for choosing heads and cams cause this guys covered tonnes of combos.

i thought that website listed builds for SBC's it list's builds for 350's only

If i'm not mistaken I beleive the guy who started the thread has a 350?....so if you look through all 108 combo's detailed and listed, there are a few 400, 406's and if think even couple 383's....can't forget a 355 .....basically standard SBC build info.