So as I have posted about on here I have done a rebuild with a Summit/Blueprint sbc block. It is 30lbs heavier than the stock block used previously.

I was running the stock block with all the exact same parts with the exception of the block. The last outing in March with the stock block I ran this>>

1.241 3.657 5.756 115.06 weather>> 70° 29.29bar 23% 27 water grains 30° dew point 1989lbs

last weekend was the first outing with the new block combination. I ran>>>

1.258 3.666 5.758 115.62 weather>> 96° 29.16bar 48% 129 water grains 73° dew point 2019lbs

Both are the second time trial so everything heated up and running all out with the sun out. Putting this through the Wallace calculators - HP from 1/8 mile with Correction.

It gives me a hp number from March of 466 and hp from August of 450. Did I really lose 16hp based on the numbers above? I'm on alcohol. Help a dumb guy out.

.

I don't know what the correction amounts to, but considering the difference in atmosphere, you're actually going to make more HP in comparable atmosphere.
MPH is your best indicator of HP.

quote:

Originally posted by Goob:
I don't know what the correction amounts to, but considering the difference in atmosphere, you're actually going to make more HP in comparable atmosphere.
MPH is your best indicator of HP.

That is my thinking. Running the same in worse air should take more hp.

Maybe fat fingers on the keyboard? I don’t know. I honestly don’t think you lost any power. Worse air and heavier, you ran the same basically. That to me indicates more horsepower not less.

Don't see anything to worry about at all, put a dial on it and race.

Are you racing for Tulsa at the bracket finals this weekend?

quote:

Originally posted by Big Steve:
Don't see anything to worry about at all, put a dial on it and race.

Are you racing for Tulsa at the bracket finals this weekend?

I am not because I wasn't sure how this engine was going to work out so I didn't sign up or plan for it. I wish I were but it's quite a drive.

quote:

Originally posted by Wooley:
Maybe fat fingers on the keyboard? I don’t know. I honestly don’t think you lost any power. Worse air and heavier, you ran the same basically. That to me indicates more horsepower not less.

I did it multiple times and get the same answers. Just not sure what I am missing that the math is picking up. I do believe I picked up hp, I'm just a little confused.

I would suspect something amiss in the calculator. Do you have the corresponding D.A. figures for the weather conditions on those 2 runs?

Those numbers appear to me to have No Correction Factor applied.
Regardless, you obviously did a good job on the build, and it should easily outperform your baseline numbers when that good Fall air rolls in.

quote:

Originally posted by FootbrakeJim:
I would suspect something amiss in the calculator. Do you have the corresponding D.A. figures for the weather conditions on those 2 runs?

Those numbers appear to me to have No Correction Factor applied.
Regardless, you obviously did a good job on the build, and it should easily outperform your baseline numbers when that good Fall air rolls in.

Jim, I use the Altronics Altitude from my weather station not the standard DA but these number are

1516 March
3711 August

You're also 30# heavier, which, in popular legend, could be up to .03 in ET.

quote:

Originally posted by CURTIS REED:

quote:

Originally posted by FootbrakeJim:
I would suspect something amiss in the calculator. Do you have the corresponding D.A. figures for the weather conditions on those 2 runs?

Those numbers appear to me to have No Correction Factor applied.
Regardless, you obviously did a good job on the build, and it should easily outperform your baseline numbers when that good Fall air rolls in.

Jim, I use the Altronics Altitude from my weather station not the standard DA but these number are

1516 March
3711 August

Does it calculate Vapor Pressure?

I've always gotten about 35+ HP difference on the Wallace calculator between calculated by ET, or MPH.

My car is super efficient @ 60'-330', but doesn't MPH very well.

Based on Weight & MPH, I am getting 471 HP for the first run, and 485 for the second run.

Using Weight& ET, I get 550.0 and 557.72

These numbers are all from the Wallace calculator, with No Correction factors.

Can you correct runs before at a sea-level correction then do the same for the new combo?

Ok I see it in Wallace now.

I do not see anything to worry about. The new motor ran under much worse air conditions and still ran basically same.

looks to me like your making more power (MPH as someone indicated) and your 60ft times and 330ft are not as good (likely track conditions) and car made up some in the last 1/2 where it was better able to hook.

Put a dial on it and work on making sure its consistent. Who cares if its 5.7, 5.8, or 6.2. I usually only care about where I put the 3rd digit.

Well the question was more about why the calculator was showing a loss when I hoped for gains. I thought maybe there was an anomaly I was missing and someone smarter than me could point to what I was doing wrong.

To be honest though most but not all of us care what it runs. I mean, who wants to slow down? I certainly don't. Yes consistency is what rules our world but I like being the faster car most of the time.

You ran the same ET 30 lbs heavier, and in 100 more water grains.

Am I seeing that right?

My car slows considerably from 20s water grains to 120s.

You can't burn water.

quote:

Originally posted by moparacer:
You ran the same ET 30 lbs heavier, and in 100 more water grains.

Am I seeing that right?

My car slows considerably from 20s water grains to 120s.

You can't burn water.

I did after changing to the aftermarket block and everything else staying the same.

Even the same machinist for both. The older combination with the stock block pulled 10" of vacuum and the aftermarket only pulls 6"-7". I had my pistons coated with Line2line abradable coatings and we were a little tighter on the PtoW clearance of the stocker than this one.

quote:

Originally posted by CURTIS REED:

quote:

Originally posted by moparacer:
You ran the same ET 30 lbs heavier, and in 100 more water grains.

Am I seeing that right?

My car slows considerably from 20s water grains to 120s.

You can't burn water.

I did after changing to the aftermarket block and everything else staying the same.

Even the same machinist for both. The older combination with the stock block pulled 10" of vacuum and the aftermarket only pulls 6"-7". I had my pistons coated with Line2line abradable coatings and we were a little tighter on the PtoW clearance of the stocker than this one.

Wait to see what it runs in comparable weather. I would have to do some figuring but I bet my car would slow up a tenth if you add 100 grains of water. At least. I am on alky.

I am a huge fan of L2L coatings. I had my pistons coated due to piston to wall clearance issues 2 years ago and its still quiet as a mouse. Used to sound like a diesel when it was cold.

quote:

Originally posted by moparacer:

Wait to see what it runs in comparable weather. I would have to do some figuring but I bet my car would slow up a tenth if you add 100 grains of water. At least. I am on alky.

I am a huge fan of L2L coatings. I had my pistons coated due to piston to wall clearance issues 2 years ago and its still quiet as a mouse. Used to sound like a diesel when it was cold.

Barry, BP758 on here, gave me a good review of it so I tried it. Same problem for me I had large clearance on that old block. It's really good stuff.