Well my solid roller 383 was finally wrapped up and dynoed today on the engine dyno. The combo is an EB ported AFR 220's, Accel pro ram intake, 259 267 108 lsa cam .57x lift, T&D rockers with 12.15-1 compression. The car is set up for fuel injection but the shop does not have the ability to use fuel injection on the combo so I borrowed a 750 carb to put on the combo for the dyno and a standard mechanical advance distributor. We only made one pull to 7200 rpms with a very conservative tune and the combo made 520hp@6500rpms and 480 ft/lbs@5000rpms. The egine builder says that the 750 is way undersized and he has no doubt a 1050cfm dominator would net another 60-70hp as he said the power flattened out at 6500rpms. The engine made 472ft lbs at 4000 rpms so it is a torquey engine. The engine builder said there was no use in him dialing it in (more $$) as I am fuel injecting it anyway but I wanted to have it dynoed and valves adjusted etc so that is the only reason I dynoed it this way. The combo was also dynoed without the crankcase vacuum pump which should also net me another ~10-15hp. All in all I am very happy with the numbers and expect somewhere around 600-620 crank horsepower once the engine has the fuel injection, vacuum pump and proper dyno time/ break in. I am shooting for mid to high 10's NA and low 9's on the bottle.

Matt

 

mine runs mid 10's with a 750 carb and a stock ported head 128 mph

I would hope your is faster.

 

Me too...but I will have to work against 3.70 gears (for the bottle) and a 3500 raceweight so if goes mid 10's set up for the bottle I will be happy.

 

I'm 3500#

the only thing that will probly hurt you is your converter...... I have a o.k. 60' low 1.4's

 

Very nice, please post up the final dyno #s and track times when it's all sorted out.

 

I also forgot the mention that this was dynoed with standard 1 3/4" dyno headers and I am using 1 7/8" hedman race headers with the stahl flange so I should be able to pick up a decent amount with the exhaust as well.

Lloyd Elliot speced the cam and said that the cam is optimized for big tube headers so I am confident in my expectations.

 

Very nice Matt and would like to see those on my 383...

Question: Where does he get those inflated no's by going to a 1050 CFM? From my analysis, I show that pretty much you can only pick up 4-6% of your HP going from 750 to 1050. In your case, this would be 0.04 X 520 = 21 to about 0.06 X 520 = 31 HP.

I really want to know if I am doing my analysis wrong.

 

Your analysis looks good. The engine builder was refering to dialing it in with the 1050 carb. They only made one pull with the engine with conservative jetting and timing. So with tuning alone it would pick up ~30hp and probably another ~30-40hp with the carb. I should have made that clear in the posts above. The goal was 600+ N/A horsepower with the combo.

 

What was the AFR and the timing at?

 

They did not have a wideband on the combo so they just went by EGT's. I am not sure what they were but I thought I remember him saying they were around 132x degrees. The timing was at 36 degrees. (I am posting from a friend's house under his login)