Nah you didn't hurt my feelings. I'm not an Internet argue kinda guy and am just gonna get evidence first like you said. I am guessing flywheel and my guesses are based on many races not just one or just watching. There were hours spent on the heads and everything else. The ports were cnc'd thanks to a buddy that owned a Cnc machine. 2.05 valves were installed(only come 2.02). They flow much better than Darts "WET FLOW" numbers and i dont care what any body says they make power, they are not the older darts. I have seen many 383's on the net with comparable builds specs and short rods (<tq) around 500 with hyd. Roller. I have solid. I have a little less dur, than some, but more lift than most with .630. It is a custom grind and tweaked int/exh open/close. was ground from billet blank. I have never floated the valves and go over 7k often. One of the best ways to increase hp is increase rpm redline or ci. They are just air pumps. A 396 turning the same rpm's will make more hp than a comparable 383. It could make the same as a larger engine turning slower if VE is same. My motor was built on a plan not a whim. The compression is built on top end and it screams from 3-7k. I started off limited by ci so I had to make up in ve and rpm. All in all I will just say it's just your plain old run of the mill small block... Wanna run em
The new ss's run 8.5-8.6 at my track btw over many watched and raced passes. 1,900 ft alt. isn't that high either.

 

You have to understand anyone that has been building race engines for any amount of time has heard of the 500Hp street friendly cars that are way faster than anything every built using the same parts and the extra special one of a kind CAM grind. I have been hearing it for 30 years. But when the Dyno results are in and the slip times show 12.5 seconds we find out it is not much different then every other car that has those parts.

Power comes from the Cylinder design, Fuel mixture, Pressure, Timing, area of the piston and the length of stroke. All the Heads, Valves, intake can do is make sure there is no bottle neck in the air/fuel supply. In a perfect world you have a fully loaded cylinder at Bottom dead center. Without a Supercharger or a turbo charger that is the maxing HP the motor will output.

When a race team designs a motor they pick an RPM range. For our car is was 6400-7200 RPMs. They then get the Cylinder heads and intake flow tested and design a Custom Cam that will NOT starve the motor at the Max 7200 RPMs. Course the motor can go higher but the design guarantees not to starve the cylinder at Max range. The complete lack of concern on how the engine reacts at 4000 RPMs most likely will be the engine is useless on the street. If your Intake/heads/Cam start to starve the cylinder it is very easy to see on a Dyno. We tested every engine for tune and starvation at 7200 RPM before it was allowed to move to the track.

There is no special combination, race machine shops do not build motors only to be surprised by how much power it makes. It is all by design and predictable within +/- 5%. The best engines are the ones that have been developed by a builder of a course of years, he is constantly tweaking and refining. He knows exactly what each modification should yield. Not a “one of a kind motors No one knows why it so much faster but it is”.

If you really had a 550HP SB with 9.5:1 compression how much power would in make on 14:1 and Cam2 racing fuel at a full 38 deg of advancement? 750-800?

 

So basically what I said. My builder has been building for 40+ yrs and has built 100's of race engines for everything from mudders, to drag cars, to roundies. I never said I had 550 just asking for guesses. The motor was not dynoed but he guessed based on calc and exp that it was just around 500/500 motor. We will see when I get stall and gear what it runs and I will have a video. If it dynos less who cares I just had it built to run with the new ones and it does it's job. I never said I built it either. The guy has been a family friend and traded with the family business for over 30 yrs. I know he spent time on it and he did all the calculations. He did build one kind of similar ( diff cam obv) for a pro mod roundy that won ten out of twelve races at local track although he was track tech,( kinda fishy as he had to inspect winning motor if challenged) It did have like you said 13.5:1. I think I am looking at wrong number anyway tq is what is prob winning it for me, but I assure you it pulls hardest when shifted around 72-7300 and runs faster mph than shifting anywhere below, this was experimented with over many passes. I know for a fact the gear and converter change will improve this time. I understand you need evidence and I assure you I am not a teenager nor in my 20's. I am trying to find his trick, bc I didn't buy his combo at first, skeptic, but it has performed. He wouldn't give me cam card or share certain specifics. Dude head design is way more important than you are leading on. Why don't racers use stock vs aftermarket heads. I have always been told heads are best investment. You can't change cylinder design they are cast in. You can bore them, but that's about it. The pressures you refer to are controlled by cam timing and head all the piston does is move up and down the only variance would be in ring seal as to whether or not the 'cylinder' was efficient at drawing or expelling air. If the heads are the limiting factor it wouldn't matter if you had a perfect circle and seal. They control the flow of the air pump or as some call em motor. A lot can be done as you said to tweak pressures, but it is relavent to flow restriction and that is in head not cylinder. That is why increasing velocity increases torque and increasing volume increases hp. Usually when you have a high velocity due to smaller ports you have a tq motor, bigger but slower is what some call a hp motor. Truck pulling/ drag car. I am familiar with all this. Thanks for all of your replies. I am not saying this is faster than all others btw I get beat at track by trailer queens all the time. I am just trying to figure out how it runs the way it does.
This calculator was one I used. The gear is skewing the numbers. 2.06 avg 60'. I usually mph most around me by 4-7. So I figure it would run a better 1/4 than calculators represent but have no evidence. I do know I am pulling the cars that are near me at line even if they get to line first I am mph them. My buddy is now trying to tell me 305 camaros came with 2.41 in 78 and v6 and 350 came with 2.73 with perf opt being 3.08 for auto. can anyone verify this bc I feel like it is 2.73. So far nothing has been mod so I assume gear hasn't. Cruising at 70 nets about 1900 rpm with 25" tire.
7.98@97
1,900 elev.
65*
45%hum.
About 3300 with gas, I weigh 200.

Calculate HP with HP Correction from 1/8th ET- Wallace Racing

 

I've found that the wallace calculators are some of the best and I've compared them to numerous time slips of mine (300+)

Again, I make over 500hp at the wheels and run over a second faster then you to the 1/8th mile and about 12mph more. This is on a tight nitrous converter but WITHOUT nitrous, so comparing apples to apples.

I do believe you're right that a good converter/gears will wake the car up, but your mph will still show through and its not.

I will be very interested to see what you actually make on a dyno as Gorn has said, we've all heard the car show guys say how they have a 500hp small block blah blah blah. I'm skeptical to say the least.

 

Yeah I agree. We will just have to wait and see. I figure like you do in that I will see et drop but mph to be within 3-5. Again I am looking at flywheel not rw. I know I lose about 15-20%. I have seen cars run .5-.7 faster and have slower mph. I am skeptical too. I asked for 500 ft lbs as the goal of the build so would like to know if I got about what I paid for. Was cheaper than a comparable crate by quite a bit and I am happy.

 

http://www.strokerengine.com/StrokedEngines.html

Here is an interesting article written by engineers and people with experience I read a while back and have been able to track down. Technology has come a long way in 15 yrs. one thing the build sheet doesn't reflect is the attention to detail. Like the billet main caps and ever heard of crank girdle. Ah that's how it turns so fast and not explode. I have personally seen 2.02 valve 383's eclipse 500 at less than 7k. I had 2.05 valves put in and after cnc'ing i believe were a true 206cc port perfectly smooth entry. If I had more CA in my intake I bet I could shift at 7500 and still be making power. I took out as much material in critical areas of intake as I could by hand in areas cnc couldn't get. Trust me I am one of you and know what a skeptic is. I deal with retard import owners all the time. I like saying its just a smallblock anyways. The number question is my personal curiosity not to brag about it. I am happy if it has 300 hp as long as I keep winning races. I wish I had sprung for dyno but all my $$ went in build. I feel it is a waay better build than blueprints claim of 485 hp 500ft/lbs 396 they are selling all over the net. That is what piqued my curiosity to begin with. A buddy asked me why I spent so long on it when I could just have bought one of those. Cost was about the same as theirs dressed but I had dressings..lol I feel like I have a better build as I can out rev it by over 1k rpms. It has more cr, but I have bigger valve and more lift to rev more.

 

I have sat on the bench long enough. You want opinion here's mine.

I studied your build sheet and things stick out to me left and right. Nothing to say this guys a liar or anything but more of a this is a stump puller. I'll start with the 1205 intake runner. All that CNC work and thats as big as he went? Why? The valve seams small too. Why not go to 2.08? These are things I am used to on a 7000 rpm motor. Also all a CNC does is cut what ever program is installed, crap in = crap out. If he has a solid port file then so be it, the CNC just replicates it over and over.

The cam isnt that wild and while you say he didnt give you the card he gave you enough. Its not that much different than mine. 232*@.050" is a bit small for the rpm. Mine is 232/239 and is done at 6200 rpm. ICL is the same.

Here are my thoughts. Your motor is a torque monster and over coming the rear gear issue. Its a Looong stroke with small runners.

One thing that stuck out the most is the Bob wieght. Its 200g less than mine and I have a long rod 383. I have fairly light pistons because of this. The extra .300 of rod length isnt worth 200g. I suspect this is why it freely turns so high.

Notice I havent given an answer? All the horse trading should have saved you enough to dyno it. You wanna know then dyno it! Myself, I have a hot small block. My neighbors though I had a street stock car until they came around the corner. Dunno power. The BS stops when the green light pops.

 

Thanks 77nomad. That is the way I feel. I just get asked all the time how much hp you got. I don't know what it has is what I tell them. That is another point if it truly is a stump puller and overcoming gear would a gear help or hurt. I questioned him all along the way and he seemed to be able to explain the reasoning. The guy is like an uncle almost. He did mention the bob weight was lighter than a 350 and it would rev quick. Also has 10" converter but only 2200 stall. He did not like the intake and said all he could do was open it up some. Said I would have to use a 2" phenolic. It runs .1-.2 quicker and 2-3 mph shifting at 7200 then at 6200( maybe I need to check accuracy of tach?). So that says it is still making power there right? Tried in increments of 300 over three passes each and averaged results to get shift point since I have no dyno. If it is monster tq low hp a gear would hurt. I have been out of racing for ten yrs and things have changed to say the least..lol back when I was in school 350hp made you king of the hill. 383's were exotic back then. I'll just stick to its just a plain old sb until I get $ for dyno. Oh he builds roundys and strip motors for a living so I bet he has several programs would be my guess on the Cnc. He has a good gig it seems. Track tech and builds motors.

396ci Small-Block - Chevy High Performance Magazine

Chevy 383 Engine - We Build a Small-Block That Makes 500HP and 500 LB-FT - Hot Rod Magazine

Air Flow Research
It seems to me .03 valve size equals 500 rpm increase in rpm redline.
Was curious so I googled 396 hp output and a few others. Don't usually read mag articles but found interesting.

 

I read the first one. It confirms my thoughts. They used a bigger valve. A cam with 242* @ .050" and shaft rockers with a 1.75 ratio. That put their cam at .667" of lift.

It did make around 550hp with a cam similar to yours. But still the induction is much more free flowing. BUT this is a car rag motor and I will almost certainly bet they inflated some numbers.

 

If your time slips are quicker shifting at 7200 vs. 6200, it doesn't mean your engine is making more HP at 7200 than at 6200. It could mean that your rearend ratio and trans ratios make it quicker to hold the shift off for another 1,000 rpm's. This also will only be proved with a dyno run, so you'll know where it makes peak HP.
Even though your engine is set up for torque, it will still be benefitted with a lower geared rearend. In the 1/8 mile you're probably not even getting into drive, as the combo you're running and 7200 rpm shifts will finish the 1/8 before you ever get done with 2nd gear. Even with 3.73 gears in mine I barely get into drive in the 1/8 mile, and I'm shifting way lower than you are. If you were to swap to a 3.55 or 3.73 rear gears, I'd think you would gain a half second in the 1/8 mile.