[JOE ALLAN]

Originally Posted by NHRASuperStock455SD

27.99, 90+ degrees, 50% humidity and it pulled an actual 685HP? That is one killer engine.

Lynn

SIR: You are correct.. In that weather if everything is rite then it is one hell of a motor, Now a question for you Lynn, you are a super stock racer so i think you understand weather correction factors....if you had a motor on a dyno say at a phyical elevation of 1600' and the weather was 93 degrees - the humidity was 50% and the uncorrected barometer was 27.99.. what corrected altilude would this correct to by your numbers? Thank You for any response.........Joe Allan.................ps. not try'n to take anything away from anyone, just try'n to understand.

[Jack Gifford]

I need to point out that I am also in awe of the work on Jim's heads, and have no doubts that it's a killer engine. The only reason I posted here, is to learn why a dyno program (or operater, whatever) would add a "friction" value to the torque measured by the dyno's absorption unit.

[BVR421]

Originally Posted by pontiac jack

I need to point out that I am also in awe of the work on Jim's heads, and have no doubts that it's a killer engine. The only reason I posted here, is to learn why a dyno program (or operater, whatever) would add a "friction" value to the torque measured by the dyno's absorption unit.

Im not sure anyone knows other than the people who make dynos. LOL Maybe a email to Superflow would answer that? FWIW, when Keorner Racing was tuning my HiPort 482, Jeff told me he thought the friction factor was silly because "what motor operates with no friction?" Furthermore the friction tables are pretty generic using bore and stroke to calculate. While making pulls he used the software without a friction correction as his tuning preference, not sure why, then added the correction in when we were finished just so the numbers would be "like every other dyno"
Speaking of pulls, a tractor pulling a sled has to be the ultimate dyno! Go or No Go LOL

[NHRASuperStock455SD]

Originally Posted by JOE ALLAN

SIR: You are correct.. In that weather if everything is rite then it is one hell of a motor, Now a question for you Lynn, you are a super stock racer so i think you understand weather correction factors....if you had a motor on a dyno say at a physical elevation of 1600' and the weather was 93 degrees - the humidity was 50% and the uncorrected barometer was 27.99.. what corrected altitude would this correct to by your numbers? Thank You for any response.........Joe Allan.................ps. not try'n to take anything away from anyone, just try'n to understand.

Just got our Computech weather station out. This unit is pretty accurate. As a base run we input a 9.85 run @ 3462 feet. This is an actual run at Joliet last summer. If we do the ET at a sea level run it would run 9.60. This calculates to 568HP for the 6X motor corrected to sea level.

Now lets put Jim's motor into our Grand Am with 685HP. This calculates to a 9.26@147mph. Now let us correct to sea level. [email protected].

The calculated HP 90 deg, 27.99, and 50% is 773HP from the actual dyno sheet corrected to sea level.

Lynn

[65nss4spdGTO]

Lynn,

Since we are talking about high horsepower and head flow, what is the fastest a D-port head and round-port head pontiacs have gone is legal super stock?

[JOE ALLAN]

Lynn: Thanks for get'n back to me with that info, Jim will have a hard time run'n the et because he's one of them 10.5" tire guys......If he's got the power he claims he'll have a hell of a time try'n to hook, I just got back from the races this weekend, talk about cold and windy but lots of fun....Later Joe

[goquick]

Lynn,
Does the 428 block code such as say a YH small valve block have to use the small valve heads or could it be used with say #16's?

[R 70 Judge]

Originally Posted by JOE ALLAN

Jim: Thanks for get'n it straight....I just went out and got my numbers and stuff, this was before i saw you last reply, so using my numbers and using the 1900' because i hadn;t seen you new post that said the phycial elevation of the dyno shop was 1820' i came out with a corrected elevation of 4862'.. now my numbers are always about 400' different that thoughs that use the altimeter because i just correct the uncorrected barometer...(which was -.8 which made the corrected barometer 27.19 - same factor you had) but when corrected .....my figures if your hp is rite for (1820) 1900' the 685 hp does correct to 805+ hp....that said even though we got different ways to get the results we come out with the same final numbers. So far we are on the same page just doing it different.....Ok.....now you say that Abilene drag strip has a static altitude of 1719' which is rite for when the weather is 60 degrees-0humidity and a barometer reading 29.92..........now when we get that bad texas weather it changes the altitude to be more like 3300' thats why when we race we have to use correction factors or a weather station info to change the dial in......i know the static elevation did not change but the poor weather make the car engine feel like its run'n at a higher altitude.....Ok.....Now by my Power to weight figures and useing you T/A weight of 3565lbs. ... and just for example we say the Corrected weather at Abilene raceway is about 1900' (Good Day) you have to divide 3565 by 685 HP giving you a P/W factor of 5.204 which by my numbers says you should run (131.00 in 10.07 et in the 1/4) 1/8 th mile should be close to 107.00 mph in 6.30 if you are using a trans-brake.........with out it maybe 6.55 et....... last time i seen you run you had 10.5'" tires on your car so hook'n is gonna be hard to do unless the track has been prepared......now at sea-level i got close numbers of 139+ mph at 9.55 et in the 1/4 mile and 113+mph in 6.00et for the 1/8 th mile............now this is just my quick figure'n.. not down to the ants ibrow....... the et all depends on the weather conditions and how good the track is........the mph is more easy to figure so it will be closer......now all you got to do is run that thing and we'll see if you got the hp.........them heads are pretty but in life i learned to watch out for things that were pretty.. hahahahahahahaha........now they can all pick on me and leave you alone..........Joe

Originally Posted by JOE ALLAN

Lynn: Thanks for get'n back to me with that info, Jim will have a hard time run'n the et because he's one of them 10.5" tire guys......If he's got the power he claims he'll have a hell of a time try'n to hook, I just got back from the races this weekend, talk about cold and windy but lots of fun....Later Joe

BTW - The car backed up the dyno numbers at the track. 6.1@113.

[pastry_chef]

Originally Posted by R 70 Judge

BTW - The car backed up the dyno numbers at the track. 6.1@113.

Ummm.... BTW NO the car did NOT back up the numbers at the track!

I know a 467 bowtie with a REAL Honest 800 Horsepower (well 795.8 to be exact) the car is a few hundred pounds heavier and runs two tenths faster!

[R 70 Judge]

Originally Posted by pastry_chef

Ummm.... BTW NO the car did NOT back up the numbers at the track!

I know a 467 bowtie with a REAL Honest 800 Horsepower the car is a few hundred pounds heavier and runs two tenths faster!

Same track on the same day? Too many variables with weather and elevation to honestly compare the two. Besides, everyone knows the BBC stuff can easily run circles around all of our boat anchor Pontiac junk

This is what I'm going by. Is this calculator wrong?

http://www.wallaceracing.com/hpcalculatoreigth.php

6.1@113 at 3565lbs

Your HP computed from your vehicle ET is 794.92 flywheel HP and 715.43 rear wheel HP.
Your HP computed from your vehicle MPH is 839.35 flywheel HP and 755.41 rear wheel HP.

[pastry_chef]

Robertson car race weight was 3200 Lbs, DA was 1150'
http://forums.maxperformanceinc.com/...6&postcount=96