Originally Posted by 79LewisVette33

It has a new HEI distributor, I tried some lighter springs, I will try changing the weights too, thank you for the help

Originally Posted by jb78L-82

As others have stated, the torker is going to hurt a bit over a good dual plan intake and the heads and cam are paramount to maximum power generation with superior aluminum heads and roller cams delivering significant power advantages over just any aluminum head and a flat tappet cam with modest lift, 383 or not. The .480 lift cam is only slightly better than an L-82 stock cam at .450/.460 222 duration, 114 lSA and depending on the heads is not going to offer huge power gains over the stock 350.

The problem I have noticed with many of the 383 engine builds is that unless you maximize the components such as compression, heads, and cam (roller), the power advantages over a properly built 355 are negligible and often inferior. I just read on this forum of a nice 383 build with relatively modest components making 440 Gross HP on the engine dyno and another thread about a 355 build with better heads and a moderate roller cam with more compression (10:1) making 475 Gross HP on the engine dyno and more torque.

I thought about a 383 rotating assembly for my stock L-82 when I did the rebuild but decided that keeping the stock forged crankshaft, forged rods, etc was a better option that purchasing aftermarket 383 components (Just bothers me to put a 383 in a C3 since that engine never came in a C3-just me) betting that with the JE forged racing pistons (9:1), AFR 180 64 CC aluminum heads, Howards Roller cam (.525/.525), and stock L-82 aluminum intake, I could make all the power I would need for the street. I am shocked at the power the 355 makes now....its not like my 10 Z06 but its not that FAR behind....perfect for a C3 chassis, suspension, and drivetrain. Another way to look at this dilemma is consider the power that a 427 makes versus a 454, depending on the build, the extra 27 cubes of the 454 is pretty negligible on the street.

Originally Posted by 79LewisVette33

I built a 383: installed 202 aluminum heads, 1.5 roller rockers, .480 lift cam, headers, torker manifold, a 650 double pumper with vacuum secondaries, and a 700r4 transmission with a 2200 stall. It has 3.55 rear end. I expected a tremendous difference over the stock 350 engine, it is notable but not as much as I had hoped for. It seems to have more torque after it is moving, I expected more out of the hole. Should I go to a 750 carb with mechanical secondaries or what would you recommend?

Originally Posted by rastafford3164

Hey jb78L-82, can you hit me with a link to that?

Originally Posted by claysmoker

To the OP. What cam? .480 lift doesn't help much. Hydraulic? Hydraulic roller? What's the Summit part#?

The Torker isn't helping your bottom end much either.

Originally Posted by diehrd

How is the timing set ? You can pull massive power out of a motor if it is incorrect

So tell us how you set timing please .. I am only asking and not telling you so we all can see what tips or suggestions we can make that will be effective

Originally Posted by 79LewisVette33

I just changed out the weights and springs this am to recurve it. I timed it by ear.....sorry know I need to use a light but I always set my distributors by ear

Originally Posted by diehrd

Re-curve it ? By Ear ?

If you decide to do things right let us know .. Timing is so important that until you have it correct you can not trouble shoot a motor.

My suggestion is put the "by Ear" under the tool box and get a timing light. Once you have one read lars papers on timing , until THEN your really wasting everyone's time who want to help you.

Originally Posted by diehrd

Re-curve it ? By Ear ?

If you decide to do things right let us know .. Timing is so important that until you have it correct you can not trouble shoot a motor.

My suggestion is put the "by Ear" under the tool box and get a timing light. Once you have one read lars papers on timing , until THEN your really wasting everyone's time who want to help you.

Originally Posted by 79LewisVette33

What cam is best for a 383?

Originally Posted by gkull

I looked up your cam and the numbers appear mild, but this definition leads me to believe that they messed with the valve event numbers like the junky line of "Thumber cams" To make a motor sound radical, but they are all show and NO GO! Your build did not follow the description.

Your carb size is fine. The Torquer manifold was garbage from 35 years ago. It doesn't have enough distance from the carb base to the plenum bottom and it doesn't have any tuned ram effect. I've used quality single planes on my vette for 30 years. One simple single plane improvement is a .5 to 1 inch 4 hole carb spacer. It would definitely help your intake.

Your heads are an improvement over stock chevy heads.

1.6 rockers are a very minor improvement, but then it comes back to the cam not being an efficient one.

true dual exhaust are an improvement

I had a 383 with a 700R4. Only I installed a 3500 stall very efficient 9.5 inch. You are instantly in the power range and I had to install 315/17 inch rear tires in an attempt to get traction. I could do some long second gear burnouts

http://www.summitracing.com/parts/SUM-1784/

Rough idle, mid-high rpm power. Requires 9.5:1 and higher compression, 2,500+ stall, and gearing. 350+ c.i.d., largest street performance camshaft.

Originally Posted by c3_dk

I've been reading that many times now.
What is it, that makes it that bad? (one of my friendes is thinking about mounting this manifold, he has a old in stock)
It's a SBC 400/TH400 3.70 rear car

Originally Posted by c3_dk

I've been reading that many times now.
What is it, that makes it that bad? (one of my friendes is thinking about mounting this manifold, he has a old in stock)
It's a SBC 400/TH400 3.70 rear car

Originally Posted by gkull

These original edelbrock designs did not incorporate or give any thought to a tuned port giving a ram effect for increased cylinder filling. They are just poor quality castings that the ports might not even line up with the heads.

They just allowed higher flow than restrictive iron manifolds counterparts.

Originally Posted by bluedawg

It's a really crappy design, check out the team g, it come's in three rises and the lowest rise would be the one I'd pick for hood clearence and if there is any room left over you can add a spacer.