Updated my website with a dyno results page....

[blykins]

Originally Posted by Cashburn

Corrected numbers? Graphs would be better.

What do you mean by corrected? Every stuska, dts, and superflow will correct to standard conditions. I have graphs for most, just takes time to get them up there.

[Cashburn]

Originally Posted by blykins

What do you mean by corrected? Every stuska, dts, and superflow will correct to standard conditions. I have graphs for most, just takes time to get them up there.

Then you should state STD Corrected are the numbers you have posted, since the printout has both columns right? Have you received any chassis dyno numbers from customers to compare? That's always interesting and would be a great resource.

[blykins]

Very few chassis dyno sessions....but I have had several drag race motors in cars and the engine dyno numbers jive with the ET and trap speed. In fact, the dyno I use is owned by a guy who builds nothing but drag and circle track engines.

The stuska does not spit out non corrected and corrected numbers, so STD corrected is all I have.

[DAVID GAGNARD]

Originally Posted by Cashburn

Then you should state STD Corrected are the numbers you have posted, since the printout has both columns right? Have you received any chassis dyno numbers from customers to compare? That's always interesting and would be a great resource.

I'm pretty sure my engine was dynoed on a SuperFlow,but it's been almost 10 years and it only had one printout and that was for "STD Corrected" numbers.....I just assumed all dynoes were like this.......

I remember when we were getting ready to fire it up, the operator read the weather dials in the dyno room and put in the temp/barometric pressure and a couple of other things, as well as the elevation (Mean Sea Level) of the dyno before ever starting the engine........

So the printout/graph on all things was for "corrected" numbers to that dyno, that day, with those weather conditions.......

David

[blown]

Most of those numbers are good but those engine's aren't very street able with well over .600 lift the valve train will start to fail I would think and then solid rollers require quit a bit of maintenance with valve adjustment being a constant I would think?

[blykins]

What I've learned over the years is that there are varying degrees of "streetable." Some guys like tow truck torque, right off idle, some guys like 5500-6000 rpm horsepower peaks, and some guys like to spin the engines up to 7500.

With the exception of the one 11.5:1 427 FE on my page, all of those engines are street engines. That 427 was for an FIA road race '63.5 Galaxie.

Days of .450-.500" valve lifts are long gone, especially in the past 20 years, where leaps and bounds have been made in valvetrain technology. Very rarely do I build an engine with under .575" valve lift, and most street hydraulic rollers are .600-.650" lift at the valve. Those engines have very mild cams and will last forever. Now granted, I don't use NAPA valve springs and Autozone lifters, my engines get high quality valve springs from Comp, PAC, PSI, etc., and lifters are Ford Racing, Morel, etc.

On the solid roller engines, there is a degree of maintenance not present with the other engines. However, lifter technology has also jumped by leaps and bounds, and now we have pressure fed and bushed lifters that will go 20-30k miles before inspection. Adjusting valve lash every week is also a wives' tale, and with the quality of parts that are available, it's essentially a "set it and forget it" mindset. Obviously race engines should get checked more often due to the amount of abuse they take.

[DAVID GAGNARD]

Originally Posted by blykins

What I've learned over the years is that there are varying degrees of "streetable." Some guys like tow truck torque, right off idle, some guys like 5500-6000 rpm horsepower peaks, and some guys like to spin the engines up to 7500.

With the exception of the one 11.5:1 427 FE on my page, all of those engines are street engines. That 427 was for an FIA road race '63.5 Galaxie.

Days of .450-.500" valve lifts are long gone, especially in the past 20 years, where leaps and bounds have been made in valvetrain technology. Very rarely do I build an engine with under .575" valve lift, and most street hydraulic rollers are .600-.650" lift at the valve. Those engines have very mild cams and will last forever. Now granted, I don't use NAPA valve springs and Autozone lifters, my engines get high quality valve springs from Comp, PAC, PSI, etc., and lifters are Ford Racing, Morel, etc.

On the solid roller engines, there is a degree of maintenance not present with the other engines. However, lifter technology has also jumped by leaps and bounds, and now we have pressure fed and bushed lifters that will go 20-30k miles before inspection. Adjusting valve lash every week is also a wives' tale, and with the quality of parts that are available, it's essentially a "set it and forget it" mindset. Obviously race engines should get checked more often due to the amount of abuse they take.

My race engine was a solid roller cammed engine with 625 lift and around 280 duration in a 331 stroker and could have easily been in a street car,it idled nicely at 900 rpms and had plenty of low end grunt,but yet ran up to 7000 rpms without a hitch.....I'd check the valve lash once a season, usually about 30+ hours of run time and barley had to adjust 1/2 the valves.......

My street engine is also a 331 stroker with a hydraulic roller cam, 525 lift and it idles nicely at 800 rpms and pulls like a freight train thru 6000 rpms....that's what I wanted in my street car,but could have made more power with more camshaft...

As you said Brent,engine technology has gone leaps and bounds since the 60's & 70's........

David

[Cashburn]

Originally Posted by DAVID GAGNARD

I'm pretty sure my engine was dynoed on a SuperFlow,but it's been almost 10 years and it only had one printout and that was for "STD Corrected" numbers.....I just assumed all dynoes were like this.......

I remember when we were getting ready to fire it up, the operator read the weather dials in the dyno room and put in the temp/barometric pressure and a couple of other things, as well as the elevation (Mean Sea Level) of the dyno before ever starting the engine........

So the printout/graph on all things was for "corrected" numbers to that dyno, that day, with those weather conditions.......

David

I've gotten over 100 engines dyno'ed over the years by various builders and at different dyno "shops" (primarily on Superflow) and they all have a column of corrected and uncorrected numbers for both HP and TQ. It's where the rubber meets the roller though we see the numbers with accounting for actual headers, exhaust, air cleaner, etc. in use.

I know the first engine on Brent's page has been on a chassis dyno so he has access to those numbers (and graphs, and corrected) if he wants it.

[blykins]

I'll see if Gary will give me the numbers. If I remember correctly though, he wouldn't let the operator pull the engine up as high as we did on the engine dyno, so the results will be skewed. Also, the carb was set up in the car so that the linkage wouldn't let it open up all the way. Gary found it later and noted that it felt like a completely different car at WOT.

I've seen dyno numbers vary from builder to builder. I know for a fact that one engine has been dyno'd on the dyno that I use and then was taken across town to a Superflow and showed 5% higher. You'll also see builders dyno at 120 deg water temp, where I try to dyno closer to 160-170, a temp that is closer to what the car will see, but isn't hot enough to cause issues under a full load.

I also really don't agree with comparing engine dyno numbers to chassis dyno numbers, especially in a Cobra. One member here (Excalibur) stuck his car on a chassis dyno, made a pull, then removed his side pipes and made 100 more RWHP. There can not be a direct correlation when golf-ball sized pipes are used, when restrictive air cleaners are used because of hood clearance, etc. All of those things play a big part in numbers, and if the engine wasn't dyno'd in the exact same setting, then it's bogus.

[Cashburn]

Originally Posted by blykins

I'll see if Gary will give me the numbers. If I remember correctly though, he wouldn't let the operator pull the engine up as high as we did on the engine dyno, so the results will be skewed. Also, the carb was set up in the car so that the linkage wouldn't let it open up all the way. Gary found it later and noted that it felt like a completely different car at WOT.

I believe that could be due to the removal and reinstall to address the head gaskets and or the intake gasket... then again it could have simply been the stretch in the throttle cable.

The main difference in the car he mentioned to me was pulling off the dry sump.

But yeah, the chassis dyno is a world of difference in setting up the car with the engine. Too bad ours was not completely installed when Gary's car went through since it would have been good to baseline it against 40 other or so engines in the same car by different builders etc.

Keep working on the charts, it's a great resource to offer.

[blykins]

Originally Posted by Cashburn

I believe that could be due to the removal and reinstall to address the head gaskets and or the intake gasket... then again it could have simply been the stretch in the throttle cable.

The main difference in the car he mentioned to me was pulling off the dry sump.

But yeah, the chassis dyno is a world of difference in setting up the car with the engine. Too bad ours was not completely installed when Gary's car went through since it would have been good to baseline it against 40 other or so engines in the same car by different builders etc.

Keep working on the charts, it's a great resource to offer.

Thanks.

As long as everyone remembers that dyno numbers *should* be used as a general tuning tool, things shouldn't get out of hand. However, my intent was to just show what typical engine combos make, where they make the horsepower, etc. Its nice to be able to look and see what difference a set of heads can make, what difference a camshaft should make, etc.

And what David says holds true in every respect. It's very difficult to dyno an engine here or build a carb here and it be in perfect tune as you send it to a different region in the US.

[DAVID GAGNARD]

Originally Posted by Cashburn

I've gotten over 100 engines dyno'ed over the years by various builders and at different dyno "shops" (primarily on Superflow) and they all have a column of corrected and uncorrected numbers for both HP and TQ. It's where the rubber meets the roller though we see the numbers with accounting for actual headers, exhaust, air cleaner, etc. in use.

I know the first engine on Brent's page has been on a chassis dyno so he has access to those numbers (and graphs, and corrected) if he wants it.

I just wanted my engine dynoed to get the most out of what I built....I brought along my headers and air filter and it was dynoed with my headers/air filter on and also my water pump on it,so it was fairly close as to how it would be in the car....the only thing not on it at the time was the alternator.....

The printouts I saw all had "STD Corrected" on them, so I just assumed that's how it's done...

I know air density/elevation plays a big part in HP... Down here in Louisiana at sea level it's one thing,other areas are another.......I used to drag race my street car a fair bit down here and one year went to Tulsa for the Shelby meet and ran it there.....I was 4/10ths off my "normal" time and asked others if saw the same thing, one big time racer said that was normal because of the elevation change....
I couldn't believe that would make that much difference, but it does....

David

[Cashburn]

Originally Posted by DAVID GAGNARD

I just wanted my engine dynoed to get the most out of what I built....I brought along my headers and air filter and it was dynoed with my headers/air filter on and also my water pump on it,so it was fairly close as to how it would be in the car....the only thing not on it at the time was the alternator.....

The printouts I saw all had "STD Corrected" on them, so I just assumed that's how it's done...

I know air density/elevation plays a big part in HP... Down here in Louisiana at sea level it's one thing,other areas are another.......I used to drag race my street car a fair bit down here and one year went to Tulsa for the Shelby meet and ran it there.....I was 4/10ths off my "normal" time and asked others if saw the same thing, one big time racer said that was normal because of the elevation change....
I couldn't believe that would make that much difference, but it does....

David

Yes sir. Exactly.