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440 Build Dyno Results

wsutard

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Just got back from the engine dyno today. Had a blast with the pros learning and wrenching.

Hopefully someone will find this info useful in trying to figure out their build plan.

Top Torque: 550 @ 4000 (HP 491)
Top HP: 499 @ 5100 (TQ 541)
Pic of full numbers below.
Initial Advance: 10
All in Advance: 32
92 pump gas (octane booster had 0 effect)

My initial thoughts are that the HP is on the low side for this build. We tried to find more but it just wasn’t budging over the 498 number. However, at the end we realized that the dyno was running 1 3/4” headers while I will be running 2” Doug’s. Based on some YouTube test videos the extra flow of the 2” should result in 15-20hp gains ¯\_(ツ)_/¯

We tried more and less advance and it kept wanting 32. We even tried a 1” carb spacer with minimal effect on the numbers.

Specs:
‘77 block +.04
CR: 10.6
Forged crank, stock stroke.
Molnar H beam rods
Icon ic822 Pistons
Huges Solid Flat Tappet Cam (238/242 -109ºLS)
Hughes Flat Tappet EDM Lifters
Smith Bros Custom Pushrods 3/8”
Edelbrock Performer RPM Heads with a light smoothing of the ports and bowls. Measured at 79cc.
Hughes Springs (452#@.700”)
Comp retainers
Mancini Racing 1.5 adjustable roller rockers.
Edelbrock Performer RPM Intake
Holley 850 Double Pumper

Dyno Results:
Torque Run
E7867EDF-D7BC-40ED-958B-CD0CC78DA479.jpeg


HP Run
D3C88349-D037-4213-A340-8937E5AA61EC.jpeg
 
Dyno days are always a good time. Good to see your engine made good numbers.

It's easy to start to believe that every engine needs to be / is 700 plus HP. How many guys do you hear say, "I want 750HP that idles in traffic and runs on pump gas"?
500HP is a good, reliable and fun area to be in, IMO
 
Dynos vary. The good news is its not a dog and all the parts stayed in the block. Put it in the car and run it. My car has been flogged with the same engine combo; carbs, cam, compression, intake, heads, headers for 6 years. Picked up from 9.40 to 9.00. Time to hammer on it.
Doug
 
I agree with both of you. I'm not going to hunt for more HP. I wont even use all that I have now. I am ecstatic about the TQ number as I think that is what I will enjoy.

One thing that was strange about the runs was the first run back from a cool down was always the low run. We would do about 3 runs then let the oil cool down a bit, think about and make changes and then 10 minutes later make some more runs. The first run back was always low, the second run would then jump back up to around where we left off. The operator commented on how he thought it was due to the oil temp and the change in viscosity.

The really cool thing to see was how you could tell by the graph how the rings were seating themselves. The dyno operator pointed it out to me.

These guys were true old school pros. the operator was a former NASCAR engineer on Richard Petty's team, the tuner (owner of the shop) had one eye, smoked a cigarette while tuning and would sit in the engine room without ear protection with the engine at 5000 RPM adjusting the timing and looking things over. The shop itself had old playboy pictures decorating all the walls. Even the screen saver of the dyno was playboy pics.
 
Nice numbers! That is real close to my build. Same cam, 10.4:1cr, 800cfm Eddy, Stealth heads with blending in the bowls and Holley SD intake.

I am currently waiting on a few pieces to install the Hughes rocker arms and trying out a different set of springs than what Hughes has listed for the cam.
 
Nice numbers! That is real close to my build. Same cam, 10.4:1cr, 800cfm Eddy, Stealth heads with blending in the bowls and Holley SD intake.

I am currently waiting on a few pieces to install the Hughes rocker arms and trying out a different set of springs than what Hughes has listed for the cam.
Would love to hear how the springs go for you.

The Holley 850 was perfect for AF right out if the box. Didn’t need to touch it the whole time.
 
Close to my build also, mine is probably a little less as I run a comparable sized hyd ft cam and 10.2:1, has pushed my 4150lb sled to 12.8 @ 112mph with street tires and 3.23"s so probably good for mid to low 12's on tire and gear.
 
I think your initial timing is a little low for that cam, I would have thought somewhere around 18 would be in the ball park. I'm sure it would pick up vacuum and response with the increase, did you try a higher setting.
 
I think your initial timing is a little low for that cam, I would have thought somewhere around 18 would be in the ball park. I'm sure it would pick up vacuum and response with the increase, did you try a higher setting.
I asked about initial and they said it’s just for reference I guess on the dyno. Since we never really were at idle or even close to it. When I get it in the car I will change the initial and the curve so it drives better. Just will lock it all in at 32.
 
The cam is close to mine. You will like the torque.

440 bored .030=446
KB 237 pistons .003 deck height
Forged crank .010 under
Eagle 4340 H-beam rods
Comp is 10.25:1
Eddy heads 84cc with stage 1 and bowl blend
Straightline Cam 234/[email protected] 540/525 solid with 112 lsa (4* built in) installed straight up
6-pack aluminum manifold with stock carbs. (Using ProMax stuff)
Comp pro-magnum 1.5 rockers with 3/8 Smith Bros. pushrods
Comp EDM Lifters
Shop Headers 1 3/4
MSD 8546 dist.

It was dynoed at 491hp/535 torque
 
I think your initial timing is a little low for that cam, I would have thought somewhere around 18 would be in the ball park. I'm sure it would pick up vacuum and response with the increase, did you try a higher setting.

Mine (same cam) will run great set at 23° initial. My total is around 34° as higher it would ping on pump 91.
 
What rockers and did you optimize your rocker arm geometry especially if roller rockers
nice build and results
 
What rockers and did you optimize your rocker arm geometry especially if roller rockers
nice build and results
Mancini Racing 1.5 rockers. I will risk the flame that might come with this but I just bolted them up. I did look at where they sat when bolted and unloaded and they looked to sit in the center of the valve stem.
 
Nice job. Similar build to my 493 but i have less cam then you. Be interesting to compare results though as i have the 74cc heads.

My buddy just completed a dyno run on his new 505 stroker a week or so ago. 440 Source rotating assembly, 590ish lift solid Comp Cam. 1.6 Harland sharp, Stock six pack carbs / intake and trick flow 240 heads.

619HP at 6000 rpm / 650 ft lb at 4500 rpm . Pump fuel and idles nice at 750. My god it sounds mean at idle! Went for a spin and when the outboards kick in it is frightening with the 4 speed (yes its an 18 spline /dana 60) Cant wait to see what it will do on the track.
 
center of the valve stem has nothing to do with it- mostly unless way off
how wide is your pattern? you want it narrow or you are loosing both torque and efficiency
http://www.b3racingengines.com/techpages/MoparRockerArmGeometry1.asp
Ok, I’m on my third read now. I’m trying to figure out how to determine when the geometry is correct.

Assuming I use the shaft shims I would expect that the geometry is as close to correct as possible when the valve experiences the most lift?

This seems like a simple setup to check for since a dial indicator setup on the spring would provide the measurement.
 
Some things are worth chasing after, others not so much. Before you go chasing after the perfect rocker geometry, take your car and some tools and go to the track a few times. You'll find 20+ HP (2 mph) and improve you're et buy a few tenths or more, and you'll have a pile of fun doing it.
 
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