Headed to the Dyno. Any guesses?
- Thread starter LIME TWIST DART
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LIME TWIST DART
Well-Known Member
Post #40
LIME TWIST DART
Well-Known Member
How many pulls would you expect at a Dyno? As many as it takes? A givin number of pulls for your money? I'm sure it varies.
9secRR
Well-Known Member
your power and torque sound right to me for the parts you have.
I did 12 pulls on the dyno with my motor. we did 2 warm up pulls and after that it was timing and jet changes. I paid a flat rate of $600 for dyno time.
put it in your car and have fun.
I did 12 pulls on the dyno with my motor. we did 2 warm up pulls and after that it was timing and jet changes. I paid a flat rate of $600 for dyno time.
put it in your car and have fun.
Mopar to ya
Well-Known Member
Wait .... I thought the motor was in your car. Is this motor or wheel HP? Either way it's a boat load of power.
Mad Dart
Nothing to see Here!
Yes and if you need more just hit it some Juice!
I do believe that's crank HP as it's on a dyno. And you're right, it should make that A body scream.
LIME TWIST DART
Well-Known Member
moper
Well-Known Member
Dynos are funny - while they satisfy the greatest desires in all of us, they can also be fickle and play games. Same thing with dyno operators. So it may be fine. Without other numbers it's hard to tell.
The reason I questioned the head numbers is "if" your heads were averagely ported you "should" have around 265-270cfm @ .500 lift (with peak flow at or very close to 300cfm @ .600"+). That "should" be enough to exceed 550 horsepower with that cam but you're 8% or so below that . The BSFCs tell you how efficiently it's running. If it needs a lot of fuel to make the numbers you have - you may have an issue in there. What is the peak efficiency on it?
The higher indicated oil pressure will remove horsepower. Lots more than you might think at peak rpm. Ring gaps and cylinder wall finish and cleanliness can remove power if they are not "right". Valvetrain geometry can remove power... As can a belt driven water pump, cam driven fuel pump, or use of chassis specific headers rather than big tube dyno headers...
The reason I questioned the head numbers is "if" your heads were averagely ported you "should" have around 265-270cfm @ .500 lift (with peak flow at or very close to 300cfm @ .600"+). That "should" be enough to exceed 550 horsepower with that cam but you're 8% or so below that . The BSFCs tell you how efficiently it's running. If it needs a lot of fuel to make the numbers you have - you may have an issue in there. What is the peak efficiency on it?
The higher indicated oil pressure will remove horsepower. Lots more than you might think at peak rpm. Ring gaps and cylinder wall finish and cleanliness can remove power if they are not "right". Valvetrain geometry can remove power... As can a belt driven water pump, cam driven fuel pump, or use of chassis specific headers rather than big tube dyno headers...
Andwhy engine builders(really good ones...),and head porters(again ,good ones...),charge what they do.^^^^^^
My builder is charging me $500 to dyno my engine. That includes break in, setting the timing and carb (includes jetting), and the dyno pulls. I don't think there is going to be a limit to the number of pulls but if we hit our number early, I don't want to keep hammering on it, I want to get it into the bed of my truck!!
I'm sure if there's more left in your motor, the guys here will help you find it. Those numbers should be fun enough to keep you busy in an A body for a while until you sort it out. :cheers:
Mopar to ya
Well-Known Member
As I said earlier, we have a very close motor. Really close to the same. You have more compression and a little more go fast toys, so I expected us to be close but figured you to have 40 - 50hp more than I have. With everything in my motor I wanted more as well, but 500hp is a lot to get out of a sb without serious cash outlay. Here is what I got.
View attachment Dyno specs (567x800).jpg
View attachment Dyno specs (567x800).jpg
9secRR
Well-Known Member
it takes a lot to make 580-600 hp. i'm not knocking this build but it's an average 4'' stroker small block. we have all done basically the same build.
I did the same thing in 2009 before I stepped it up with my current motor. mine was a 410'' stage 3 eddie headed, 9.5:1 comp, 620 lift solid cam motor. never dynoed it but from mph and ET, it was right at the 500 hp range.
he will have lots of fun on the street with this motor and will have fun on the strip aswell.
it's a solid build without spending major $$$ and exotic parts.
I did the same thing in 2009 before I stepped it up with my current motor. mine was a 410'' stage 3 eddie headed, 9.5:1 comp, 620 lift solid cam motor. never dynoed it but from mph and ET, it was right at the 500 hp range.
he will have lots of fun on the street with this motor and will have fun on the strip aswell.
it's a solid build without spending major $$$ and exotic parts.
Fisher
Old Guy with a Cool car.
I ended up with 20 pulls on the dyno. Its better to keep the pulls down, and when you have the correct parts to begin with your not chasing after problems all day beating up your stuff.
Fisher
Old Guy with a Cool car.
And just for comparison, another small block ford on the dyno here. 434 CI hyd roller 8.5-1 compression trick flow heads, And one of the engine builders good race carbs. Made 614 HP. I would not have believed it either, but the combination of the heads and the cam profile work really well with this 434.
This is a procharger combo as well, with the belt on and some boost the motor made 870 HP.
This is a procharger combo as well, with the belt on and some boost the motor made 870 HP.
LIME TWIST DART
Well-Known Member
Here are the Print outs.
The numbers are corrected.
I think there are a few contributing factors to the lower numbers.
1) The heads were never flow tested,(lesson learned) and maybe they didn't get worked to the level of my expectation. Although we discussed stage 3, my invoice shows stage 2 and is described as Competition street/strip Bowl blend, open exhaust and intake ports, radius short turns and port match. Also, a valve job. I did get lots of pics before they were installed, but not sure what can be discerned from them.
2) They ran the motor with 1 5/8" headers. That's what they had.
3) There probably could have been a little more timing. It is @ 36.
4) They never tried running it without the tapered 1" spacer I provided or different jets, but they did feel the initial setup performed well and the carb was built specifically for this motor.
5) High oil pressure.
6) There were 2 soft pulls to 3K that showed 100 psi.
Put in thinner oil. Then 6 more full pulls from 5K to 6k+ that settled in at 75 psi. The 5th peaked at 520-TQ/506-HP and the 6th at 518-TQ/516-HP. I think a few more pulls would have showed some more power.
Of course there could be problems with the build itself. Hopefully not. I hope to enjoy the motor for a few years. Time will tell and for now, I'm satisfied. Tomorrow? Who knows. Lol.
I have to say I am pretty much a rookie at all this stuff. So, this is definitely a learning experience. Both in terms of the technical aspects as well as making sure all the steps/procedures are performed and followed through on. I hope the motor is healthy and delivers on reasonable longevity. I guess its part of the process. I plan to put the motor in and look at the oil pressure situation again. I expect it will drop a little more. If not, I'll look to make a change.
These are pulls 2 to 6.
The A/F needs to be adjusted -2. So, if it reads 15, it's actually 13. Calibration issue.
The numbers are corrected.
I think there are a few contributing factors to the lower numbers.
1) The heads were never flow tested,(lesson learned) and maybe they didn't get worked to the level of my expectation. Although we discussed stage 3, my invoice shows stage 2 and is described as Competition street/strip Bowl blend, open exhaust and intake ports, radius short turns and port match. Also, a valve job. I did get lots of pics before they were installed, but not sure what can be discerned from them.
2) They ran the motor with 1 5/8" headers. That's what they had.
3) There probably could have been a little more timing. It is @ 36.
4) They never tried running it without the tapered 1" spacer I provided or different jets, but they did feel the initial setup performed well and the carb was built specifically for this motor.
5) High oil pressure.
6) There were 2 soft pulls to 3K that showed 100 psi.
Put in thinner oil. Then 6 more full pulls from 5K to 6k+ that settled in at 75 psi. The 5th peaked at 520-TQ/506-HP and the 6th at 518-TQ/516-HP. I think a few more pulls would have showed some more power.
Of course there could be problems with the build itself. Hopefully not. I hope to enjoy the motor for a few years. Time will tell and for now, I'm satisfied. Tomorrow? Who knows. Lol.
I have to say I am pretty much a rookie at all this stuff. So, this is definitely a learning experience. Both in terms of the technical aspects as well as making sure all the steps/procedures are performed and followed through on. I hope the motor is healthy and delivers on reasonable longevity. I guess its part of the process. I plan to put the motor in and look at the oil pressure situation again. I expect it will drop a little more. If not, I'll look to make a change.
These are pulls 2 to 6.
The A/F needs to be adjusted -2. So, if it reads 15, it's actually 13. Calibration issue.
MRL Performance
Well-Known Member
Looks to me that it is running WAY to lean. Scary lean! And going by the air flow thru the engine, if its right, you should be making 550-575HP.
You want to see the A/F ratio around 12.6-13.2 at WOT. Its running to lean.
You want to see the A/F ratio around 12.6-13.2 at WOT. Its running to lean.
LIME TWIST DART
Well-Known Member
Just wanted to make sure you saw my note regarding the A/F. The print out is a misread.
Apparently there was a recalibration and it showed, prior to my pulls, that the actual A/F is 2 less than shown. So, a 15 is actually a 13 and so on.
Thoughts?
3406pk
Well-Known Member
What did you change from run 5 to run 6. Run 6 was much better in that the peak hp came higher at 6100 rpm and tq was up at that rpm also. Run 5 was peak hp at 5700 rpm and tq was down 20 pts at comparing to #6. Run 6 had more torque at all the upper rpm points.
LIME TWIST DART
Well-Known Member
These were the only 2 pulls I witnessed for myself. Unless something can be done from the control room, I would say no changes between 5 and 6. The motor was never shut down between these two runs and they were back to back. Maybe a minute apart. No one went into the Dyno room between these pulls.
I just checked. I have audio for the last 2 pulls. I know the motor wasn't touched between the 5th and 6th pulls. The 5th pull was about 20 seconds long. Then at idle for 40 seconds. Then 6th pull for about 24 seconds.
Also, the motor was at rest for 30 minutes prior to 5th pull. They had done a few pulls, but were waiting for me to show up for the last couple. So, the motor would have been "warmed up" more on the 6th pull than the 5th. Its the only thing I can think of worth mentioning.
MRL Performance
Well-Known Member
Ok, I missed that on the A/F.
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