Tony's BHP

[Alky V6]

I think that dyno number is optimistic the reason I say this is don Cruz made 800 on the dyno and he runs 124+ in the 1/8 and his car weighs 3560# also if the turbo rolls over slow the number would be lower. 25% drivetrain loss would nessatate a major revamping!!!!!!

I'm just going by what the dyno guy across the way from me has told me. He would consider 20% loss with an auto and racing TC to be very optimistic. He considers 20-25% loss just to be a start for any stall over around 2200 rpm.
Tony. Have you had yours on a chassis dyno?

I agree with you. My numbers are optimistic. Without having had the car actually on a chassis dyno, it's really hard to guess. I can only go by what chassis dyno operators are telling me.

 

[Alky V6]

20% drivetrain loss with an automatic and production type of torque converter is a real common number that chassis dyno operators throw around. It does get worse with higher than stock stall type torque converters.
We all know how much more heat higher stall torque converters generate. That heat translates directly to hp loss. Any heat generated anywhere in the drivetrain translates directly to hp loss. We know TCs generate the most heat in the drivetrain. A racing TC under full load generates an enormous amount of heat.

The cooling system of the engine absorbs roughly 30% of the horsepower generated inside the cylinder. It's amazing how much hp is lost before the tire patch.

 

[bison]

Don if you look at the actual fuel consumption vs stoic and your drivetrain loss prediction you will see one of them way off the mark when you assume your hp numbers. There is no way in hell mine or anyone i mentioned is losing 25% through their drivetrain. Well maybe you are but the rest are not. A racing converter will work better than a POS converter built with off the shelf crap. They are able to zero in the stator and direct the fluid path so that the least amount of power is lost and the einge is held at the power band the longest. In case you havent noticed the PTC converters a lot of us run work on both ends extremely well. I have about 3% slip up top. I typically see cars around 500hp picking up 50 ft lbs peak at the wheels or more on cars that had back to back comparisons with other converters vs a 9.5" PTC. They also pick up a lot of road hp/tq all the way across the board.

 

[Alky V6]

Don if you look at the actual fuel consumption vs stoic and your drivetrain loss prediction you will see one of them way off the mark when you assume your hp numbers. There is no way in hell mine or anyone i mentioned is losing 25% through their drivetrain. Well maybe you are but the rest are not. A racing converter will work better than a POS converter built with off the shelf crap. They are able to zero in the stator and direct the fluid path so that the least amount of power is lost and the einge is held at the power band the longest. In case you havent noticed the PTC converters a lot of us run work on both ends extremely well. I have about 3% slip up top. I typically see cars around 500hp picking up 50 ft lbs peak at the wheels or more on cars that had back to back comparisons with other converters vs a 9.5" PTC. They also pick up a lot of road hp/tq all the way across the board.

Have you actually done an engine dyno pull and compared it to a chassis pull using the same engine? Until someone comes up with hard copies on a test like that, I'm not going to bother getting into a debate about whose assumption is correct. I think I'm smart enough to realize I could be totally off base on this, since I'm only taking the word of someone else and have no real world comparison to go on to think otherwise. On the other hand, if you have some hard data, please share it. What I mean by hard data is like I stated above. An engine dyno pull that gives us a BHP number, and then that engine put into a car and run on a chassis dyno with an automatic transmission and whatever torque converter you choose to use.

 

[Alky V6]

Bison. How much hp, percentage wise, do you think your efficient torque converter saves compared to an average race TC?

 

[Otto J]

Have you actually done an engine dyno pull and compared it to a chassis pull using the same engine? Until someone comes up with hard copies on a test like that, I'm not going to bother getting into a debate about whose assumption is correct. I think I'm smart enough to realize I could be totally off base on this, since I'm only taking the word of someone else and have no real world comparison to go on to think otherwise. On the other hand, if you have some hard data, please share it. What I mean by hard data is like I stated above. An engine dyno pull that gives us a BHP number, and then that engine put into a car and run on a chassis dyno with an automatic transmission and whatever torque converter you choose to use.

I am hoping that on one of my next customer builds with an aftermarket ECU to get it on an engine dyno,gotta days worth of setup for a fuel injected,intercooler turbo motor though and gotta find a customer willing to pay for it.
When i build my next car it will be engine dynoed for sure before its installed

 

[HighPSI]

Have you actually done an engine dyno pull and compared it to a chassis pull using the same engine?

I have done this I will see if the customer is willing to share the data. I am pretty sure Chris Lyons also did this. I will say the engine dyno is able to load the engine at a lower rpm and give you much, much higher torque figures.

 

[Alky V6]

I have done this I will see if the customer is willing to share the data. I am pretty sure Chris Lyons also did this. I will say the engine dyno is able to load the engine at a lower rpm and give you much, much higher torque figures.

That's why I played with the NC TC so long. It allowed me to load the engine in fuel map areas that you can't get to with a higher stall TC. Those areas aren't useful after switching to a higher stall, but I still did it just for the research value. Cheap man's engine dyno.

 

[John Wilde]

Id love to see one of them nasty TSO engines in a 2300lb tube chassis. Id bet another $500 that they would go at least 195mph and likely closer to 200mph.

Brian,

Len Freeman has already gone 6.979/201.73 at more than 2400lbs.
Kenny has real dyno numbers for that combination too.
Now I realize that they run twins instead of the GT47 Based 88mm turbo that everyone in TSO runs, but we can get the idea.

BTW: I am so happy to see you contributing!

 

[turbobuick]

I have done this I will see if the customer is willing to share the data. I am pretty sure Chris Lyons also did this. I will say the engine dyno is able to load the engine at a lower rpm and give you much, much higher torque figures.

Yes we did, spent two weeks on a DTS dyno testing several cam profiles learned a lot. HP and VE table #'s are still different than what is seen on the track and on a chassis dyno. Engine dyno loads motor more than track and chassis dyno seems to load it less. Very hard to duplicate track conditions on a dyno with a turbo motor since they seem to be so load dependent.

20% drive train loss is a lot IMO especially with today's TQ conv tech. My old car was no where near that with the Bradco conv I ran.

 

[Alky V6]

Yes we did, spent two weeks on a DTS dyno testing several cam profiles learned a lot. HP and VE table #'s are still different than what is seen on the track and on a chassis dyno. Engine dyno loads motor more than track and chassis dyno seems to load it less. Very hard to duplicate track conditions on a dyno with a turbo motor since they seem to be so load dependent.

20% drive train loss is a lot IMO especially with today's TQ conv tech. My old car was no where near that with the Bradco conv I ran.

Sure would be nice to see some exact figures, or at least an exact percentage based on the numbers in question. Can you provide those?

 

[turbobuick]

Sure would be nice to see some exact figures, or at least an exact percentage based on the numbers in question. Can you provide those?

What is in question and what do you want to know?

 

[bison]

Bison. How much hp, percentage wise, do you think your efficient torque converter saves compared to an average race TC?

5-7% peak hp maybe. The average hp/tq vs mph is huge compared to other converters ive seen. Thats what accelerates the car not the peak gain. Imo engine dynos dont leave you with any predictability. Taking the converter out of the question changes the picture so much its almost useless data. Another thing to note is that we have seen a lot of lower rpm torque gain when switching to the PTC. Some cars we only saw about 10 peak but they seemed to pick up a lot of torque at low rpm and a lot of road hp. Another thing to keep in mind is that most of the cars were real street cars that are driven thousands of miles a year. This changes a lot of things about the cars combo since its built around running for many hours compared to a race engine that may run 10 minutes and see about 2 minutes of WOT time.

 

[bison]

Brian,

Len Freeman has already gone 6.979/201.73 at more than 2400lbs.
Kenny has real dyno numbers for that combination too.
Now I realize that they run twins instead of the GT47 Based 88mm turbo that everyone in TSO runs, but we can get the idea.

BTW: I am so happy to see you contributing!

That car is a totally different animal and comparing it to a TSO car is about useless. Id bet the TSO engines of Gomes and Fiscus would run damn close to that in the same chassis with some track time combo adjustment and the next 3 or so fast TSO guys would be right there also. Id also bet that if they were to throw on a single 106 and spray it they would run as fast as the valvetrain in their engines would allow them. Probably crossing a fine line of running out of room up top (or not) before huge mods to the valvetrain would be needed to make room for the cam. Im not sure what block is in the Gallina car but id again bet it doesnt share the same dimensions as a TA or S2 block. There is a lot that can be done when the $ doesnt matter. Making room for more lobe and throwing a lot of turbo and N2O on there would be a killer if it made it down the quarter.

 

[Alky V6]

What is in question and what do you want to know?

The question is, how much crankshaft hp is lost through a drivetrain with an automatic transmission and a racing torque converter?
We're looking for an engine dyno test result (BHP), and then a chassis dyno test result after that same engine is installed in the car (RWHP).

 

[Alky V6]

5-7% peak hp maybe. The average hp/tq vs mph is huge compared to other converters ive seen. Thats what accelerates the car not the peak gain. Imo engine dynos dont leave you with any predictability. Taking the converter out of the question changes the picture so much its almost useless data. Another thing to note is that we have seen a lot of lower rpm torque gain when switching to the PTC. Some cars we only saw about 10 peak but they seemed to pick up a lot of torque at low rpm and a lot of road hp. Another thing to keep in mind is that most of the cars were real street cars that are driven thousands of miles a year. This changes a lot of things about the cars combo since its built around running for many hours compared to a race engine that may run 10 minutes and see about 2 minutes of WOT time.

I'm not sure how this figures into the whole picture, but at low rpm/high load the torque converter can quite possibly be in torque multiplying mode. I wonder how that muddies the results?

edit: Is the torque multiplication making up for losses experienced?

 

[turbobuick]

The question is, how much crankshaft hp is lost through a drivetrain with an automatic transmission and a racing torque converter?
We're looking for an engine dyno test result (BHP), and then a chassis dyno test result after that same engine is installed in the car (RWHP).

I did my dyno testing back in 2004. The reason we did it was to test cam profiles. On an engine dyno we were able to hold the motor at 4000rpm till full boost then run the motor through the rpm range which gave us a nice power curve that reflected what the cam profile was as opposed to one that was increasing due to boost increasing with load.

We then designed a TQ conv based on that info. Plus the motor I ran in 2004 was VASTLY different from the motor I ran in 2009, BUT much of what we learned in 04 was applied in various ways. So I don't have any concrete data that you may be looking for to compare.

As far as datalogs from last year believe it or not I only have one good datalog from last fall on my car since I was having issues with the datalogger bugging out when I launched the car. The one log I have was a pass at PRP with trap rpm 7410 and MPH 170.20 with 3.79% slip (3.50 gear 28" tire).

Earlier passes when the car was running a 3.70 gear trap mph 167.76, rpm 7640 and slip was in the 2.57%. I have a bunch of passes in this range all about the same.

FYI I have a pic of my car at the end of the track @ norwalk with 325 radials on it at 168mph and they do grow quite a bit. Without much TQ conv loss I would say my overall drivetrain loss where pretty minimal since TQ losses are the majority of the traditional 20% drivetrain loss most speak of.

In a turbo car if you want to measure HP on the track the only real way to do it IMO is to datalog actual fuel consumption and calculate it from there.

 

[S2V6RACER]

In a turbo car if you want to measure HP on the track the only real way to do it IMO is to datalog actual fuel consumption and calculate it from there.

What does 926.3 cc's work out to be with base fuel pressure of 44psi?

 

[S2V6RACER]

That car is a totally different animal and comparing it to a TSO car is about useless. Id bet the TSO engines of Gomes and Fiscus would run damn close to that in the same chassis with some track time combo adjustment and the next 3 or so fast TSO guys would be right there also. Id also bet that if they were to throw on a single 106 and spray it they would run as fast as the valvetrain in their engines would allow them. Probably crossing a fine line of running out of room up top (or not) before huge mods to the valvetrain would be needed to make room for the cam. Im not sure what block is in the Gallina car but id again bet it doesnt share the same dimensions as a TA or S2 block. There is a lot that can be done when the $ doesnt matter. Making room for more lobe and throwing a lot of turbo and N2O on there would be a killer if it made it down the quarter.

One would have to wonder what the power gains alone from twins vs. the single 88's used would be. I'm pretty sure Gallinas car is running about 2500hp worth of turbo and we are running above the HP ratings of our turbos at this point.

 

[turbobuick]

What does 926.3 cc's work out to be with base fuel pressure of 44psi?

You measured this with a fuel flow meter?