Dynoed my engine yesterday

[rumrumm]

After breaking the engine in and tuning the carburetor and distributor, the dyno shop did three pulls yesterday on my 383. It made best power with 32 degree total advance: 450 hp and 467 ft.lbs. of torque. Sure sounded pretty at WOT! What a rush!!

[Dirk35]

Wow, thats really good! You must be pleased.

[40]

Those are pretty impressive numbers....bet you're stoked! Now get it finished and put those ponies to work!

[Mikej]

Lynn, thats great. What a thrill I'm sure.

[Bruce Dorsi]

After breaking the engine in and tuning the carburetor and distributor, the dyno shop did three pulls yesterday on my 383. It made best power with 32 degree total advance: 450 hp and 467 ft.lbs. of torque. Sure sounded pretty at WOT! What a rush!!

==================================

Congrats,Lynn!

I know you did your homework while selecting components for this engine, and it appears you chose wisely!

....Would you mind sharing some info about the carb, cam, heads, compression, etc, that you selected to achieve these results?

....What were the hp and torque curves like?

(p.s.-- I'm catching up on some posts that I missed while away.)

[rumrumm]

I had the shortblock built using an Eagle rotating assembly with 6 inch connecting rods and SRP forged pistons, 10.6:1 static compression, 8.46 dynamic compression; AFR 190 heads, Pro-magnum roller rockers, CompCams 280 magnum cam, Edelbrock RPM manifold port matched to the heads and Edelbrock 750 carburetor and MSD distributor. The best dyno results with total timing at 32 degrees:

RPM TQ HP
3100 432.5 264.7
3200 441.5 268.7
3400 435.3 282.0
3600 438.4 300.4
3800 443.6 320.9
4000 455.1 346.4
4200 463.1 376.0
4300 467.7* 387.3
4400 467.0 395.5
4600 463.0 410.8
4800 457.5 425.1
5000 455.8 434.5
5200 445.6 441.5
5400 431.2 443.5
5600 415.9 444.1
5700 404.9 449.8*
6000 378.1 431.3

Even though the DCR is on the edge, I had no problems with detonation due to the chamber design of the AFR heads and the 6 inch connnecting rods.

[purplepickup]

Congratulations on what looks like a really good build, Lynn.  It should be lots of fun.   And thanks for the parts list and dyno run data.  I've got a roller block I'd like to build into a 383.

[1FATGMC]

I had the shortblock built using an Eagle rotating assembly with 6 inch connecting rods and SRP forged pistons, 10.6:1 static compression, 8.46 dynamic compression; AFR 190 heads, Pro-magnum roller rockers, CompCams 280 magnum cam, Edelbrock RPM manifold port matched to the heads and Edelbrock 750 carburetor and MSD distributor. The best dyno results with total timing at 32 degrees:

RPM TQ HP
3100 432.5 264.7
3200 441.5 268.7
3400 435.3 282.0
3600 438.4 300.4
3800 443.6 320.9
4000 455.1 346.4
4200 463.1 376.0
4300 467.7* 387.3
4400 467.0 395.5
4600 463.0 410.8
4800 457.5 425.1
5000 455.8 434.5
5200 445.6 441.5
5400 431.2 443.5
5600 415.9 444.1
5700 404.9 449.8*
6000 378.1 431.3

Even though the DCR is on the edge, I had no problems with detonation due to the chamber design of the AFR heads and the 6 inch connnecting rods.

I like your parts selection and with that wide torque curve that is going to be a very fun motor .  I hope to have some AFR heads on a motor myself someday.

c ya, Sum

[rumrumm]

One of the moderators on the Chevytalk Performance forum told me with a roller cam and a Victor Jr. intake, it would have made 500 hp, but I could not justify this much extra money on overkill. My ego isn't that big.

[purplepickup]

One of the moderators on the Chevytalk Performance forum told me with a roller cam and a Victor Jr. intake, it would have made 500 hp, but I could not justify this much extra money on overkill. My ego isn't that big.

I don't need that much either but I do like the roller cam profiles available and I already have the block.   I'd stick to a dual plane intake instead of the Victor too.   I don't like to have to twist the daylights out of an engine to get power.  

At this point it's more just talk than anything else.   The engine in the pickup runs really nice and I'm still pretty serious about getting rid of everything else.  

....I'm saving your stats tho.

[Bruce Dorsi]

Impressive torque curve, Lynn. --- 'Ya done good!!

Thanks for sharing the details!

Out of curiosity (not criticism),  to what do you attribute the relatively-large drop off in hp and torque between 5700 rpm and 6000 rpm?  .....Could that be attributed to a too-small carb, the cam profile, or ?

Also, how did you arrive at the dynamic compression number?  ....Is it calculated, or from a computer simulation?  

Thanks in advance for making me smarter!

[PeterR]

RPM TQ HP

5200 445.6 441.5
5400 431.2 443.5

And you all know I can not resist asking silly questions, so not to disappoint you here it is.  

What would have happened at 5252 and why?

[nomobux]

Sounds like a great combo. Gobs of street power w/o twistin the h--- outta it. Good job.

[Dirk35]

Wow!
Nice indeed. I hope to get even close to 400hp with my 302 i fI can ever get the pulleys on it sorted out.

[OzRod]

That's 383 power! Can't wait to see you put that power to the ground. Good job in selecting parts.

Some good DCR (dynamic compression ratio) info here. It delves deep into camshaft theory, but really complicates things in my opinion. When selecting components I won't rely on it, just 'keep it in mind'.
http://cochise.uia.net/pkelley2/index.html

Building a 383 myself, very similar combination, and very streetable