Pretty Darn close to my setup too...with the AFR 180's, Howards roller (.525/.525, duration 219/225, LSA 110), 10.2 compression, Comp cams roller tipped 1.52 rockers, Stock aluminum L-82 intake, and Holley 650 CFM 4175 Vacuum secondary carb with a 4 speed and 3.70 gears. I forgot now what are your cam specs, again?....very impressive HP as I would expect from our combinations and proof positive that for 90% of folks who are looking for more power, a bored 350 will fit the bill perfectly if done correctly with the right combination of parts. The key to hitting 450 HP and close to 500 TQ is to spend the extra money for a roller cam and superior heads like the AFR's (instead of replacing the rotating assembly needed for a 383...its a wash in the end for 23 cubic inches).

 

First, a 383 is 33 CI more than a 350. Second - if you're going to make 450 hp with a 350, you're going to have to replace the rotating assembly anyway. Third - you continually minimize the inherent advantage of a 383 versus a 350. Do you think that changing the crank and pistons in your engine, converting to a 383, using all the same parts otherwise, would not yield more HP and torque? If so, that's why its worth it to build a 383.

 

I have to agree here.
If you can get 450 HP out of a 350 which is 1.286 HP per CI then an additional 33 CI with the same care taken could net you another 42 HP or more. It's not that hard to find a 500 HP 383.

Since HP = torque x RPM/ 5252. and the torque of a 383 with similar build goals would be higher at any given RPM then the HP would follow.
Therefore your average HP would also higher, giving you better acceleration through out the RPM range.

 

First...Actually its neither...typo my bad..correct 33 more cubes for a 350 versus a 383, 28 more cubes versus a 355 like mine...

Second...in my case, did not replace the rotating mass except new forged pistons...reused forged crank, forged rods.

Third...Many people do not use the components that I did in their 383's nor do the crate engines commonly come so equipped. Of course if they did, the 383 would make more power.

Fourth...not a fan of the 383 for C3's (never came with such an engine) and if I was going that route, I would be more inclined to use a different block to really make a difference.

Fifth, Unless you are looking to make 500+ Gross HP from a SBC 350, my opinion, is that a 350-355 built correctly will get you easily to 425-475 Gross HP and for less money...just my opinion

 

Like I said, if you are looking for 425-475 Gross HP the 350-355 is more than capable and for less money. 500+ Gross HP than the 383 is the ticket....Then again if I was going for >500 Gross HP, the 383 would not be my choice...

 

I'm in the same boat as you. Although I did not bore mine to a 355. I opted for the 350 since it's only a 4.00" bore once and mine was in good shape.
I really wanted to see what I could do with a 350. Bought the Dart SHP's so I could experiment with porting. For sure the AFR's would have made more power out of the box. A 383 however is a good option for a guy who wants more power and torque with the 350 block.

When the time comes and the 350 no longer interests me, I'll step up to a 406.

 

 

Those are VERY good links, thank you! Looks like with a change to better 64cc Edelbrock or AFR heads, I have a lot of opportunity to adjust the cam. Are there certain rockers, lifters and rods that I need to get to allow a future cam swap or are they relatively interchangeable? As you can tell, I have little experience with this!

 

What tool can I use to tell how big a bore I have? When I had the engine rebuilt 12 years ago, I thought I was told it was bored 30 over. As I dig in to this project I want to make sure I am getting the most effective heads for my application. If I have a 383, would AFR 220 heads be better than 180 or 195s? I guess which heads would allow me to move from a mid 450s cam to a 515 cam or should I be looking at the cam duration?

 

it would be easier and cheaper to do it all at once, 1 time replacing oil and antifreeze. 1 time adjusting valves, 1 intake gasket set.

 

There is more than one way to measure the bore. Cheaper way is to use bore telescoping gauges and then measure them with a micrometer.
You can get them from Harbor freight to save on $$.
The more accurate way to measure them is with a Bore dial gauge.


Either is acceptable, the bore dial gauge is a lot faster though and you don't have to measure and remeasure to make sure you got it right.
For checking 4.00" vs 4.030" you could probably just use the caliper micrometer by itself.

From the nature of your questions it is apparent that you have lots to learn to do this right. I don't mean that in a condescending way it's great that a guy wants to do it himself and get it right.
But to get it right you need a good reference. The book I recommended previously is a good reference. It's still relatively current and relevant information.
The internet is also a good reference but you have to know what to look for. That's where reading form a experienced source comes in you start to recognize and understand what is bs and what is not.

As heads go for a 383 I would likely recommend the 195's over the 220 heads for a street driven car.
If you're drag racing primarily then maybe bigger like the 220's.

Cams is a science in of itself. I studied them for a year on and off before I pulled the trigger. Still learning what is good and what isn't depending on the use.
I found the cam company recommendations were all over the map, so I couldn't really trust them.
So duration is only one factor. lift is another, then you got Lobe separation angle and intake valve closing angle. Those are the biggies.
The book will guide you on that as well.
Do a search on cams and see all the threads that pop up and the many, many varied answers regarding which one to use.

P.S. it occurred to me that you may be confusing the size of the intake runner in cc's with the CFM flow of the heads. The 195 measurement is the volume of the intake runner not the flow capacity of the head. It flows much better than 195 CFM.

 

For the average street driven 383 I would go no larger than a 195cc head.A 180cc head would work fine for a driver(not interested in max performance)with a smallish cam.

Just about any rocker will work but I tend to stay away from the cheap overseas stuff.

Several good guys here who can spec a cam.I will say err on the small side and you will always be happy.Nothing sours a build like an overcammed hard to idle in gear big that doesn't do anything well.

All the parts should work in the desired rpm range together.Your tranny,torque converter stall speed,and rear gear ratio all play a part in your selection.As well as your intended usage and BUDGET.

Before you do anything figure out how much you want to spend on it and include labor if you aren't doing the work yourself.

Your current cam is fine(for now)and if I had a recommendation it would be to do the top end swap(heads and intake-carb optional)as well as TUNING what you have.If you decide to buy/build a 383 short block later then all you need is a cam and some roller rockers to go with your existing top end.

 

I agree completely, if you are changing the crank rods and pistions, the rotating assembly for a 383" cost's about the same and you spend a little extra money on clearencing if you don't do it your self. all parts being equal except the stroke, the 383 will make more torque but at a lower rpm as the extra stroke will use the duration sooner in the rpm range. 500 horse with a 383" seems common these days and not reving it to the moon, 500 horse out of a 350" while more common than it use to be, is not as common as making it out of a 383" and when 500 horse is achieved outa a 350" seems like it's done at a lot higher rpm.

 

The 220's would make more power and would do it higher in the rpm range, I'd figure that with a 383" the afr 220's would be making peak power in the 7200 to 7500 rpm range and would take a larger solid roller such as mid 250's @ .050" , higher compression 11ish to 1 range, higher stall converter (3600 to 4000 rpm range) and deeper gears (3.90 to 4.11) to make the combination match accross the board. With afr 195's you could make 500 horse and do it with 10 to 1 compression, 3000 rpm stall, 3.7 rear gears and mid 230's @ .050" duration hydralic roller. You could probably make 480 horse with the afr 180's you could make 480 horse and use a high 220 to 230 @ .050'' with a 2400 rpm stall and 9.5 to 1 compression and 3.55 gears and would display more low end torque than the other two. with the 220's would probably put you in the mid to high 500 horse range and could be streeted but would be rwody for sure. the afr 195 cc with the 76cc chambers and flat top piston would in my opinion be a real good street combination.

I agree, I did the cam shaft after the heads on the l48 and it is twice the work and extra money toward gaskets and such.

 

AFR told me 195 would be best for my 406 with 234/244 @.05 .489/510 700r4,355s.

 

I have the 195's on my 400" with 236/242 @ .050" .520" .540" hydraulic roller and it peaks around 5800 rpm using an rpm airgap, I could probably get it to peak at 6500 with the right cam and the single plane I'm running now. I think that with a set of comp ported 210's or regular 220's could probably peak at 6800 rpm and use either a valve trian design that was built for rpm's or a solid roller. I like the 195's for my present use. With the dual plane, 2400 rpm stall and 3.08 rear gears I was turning mid 12's and 108.8 mph(experimentation with an open spacer versus a 4 hole space showed that the engine was responding better with the open and lead me to believe that a single plane would net better gains), I've since swapped to 3.7 rear gears and a weiand team g medium rise single plane plus this spring I'll be swapping to a smaller diameter 3000 rpm stall and hoping to hit high elevens. If I can make it to the track with said changes this summer and chart some good times and speeds, I have one of straubs camshafts 233/236 @ .050" .57" lift with 1.6 rockers to run a comparison all things same except the camshaft and the 1.6 which comp recomended against, to see if Chris's selection in camshaft turns ether a higher mph or lower et then the cam shaft that I picked, should be interesting to see the comparison. I have a magnusion mp122" in the garage for when I start to get board with the n/a configurations.