3x8 Dyno Charts

very interesting, thank you for sharing.

Now we can compare the shape of the real Dyno chard to the officiali power diagram released by Ferrari.

Here below is the famous early carbed Euro cars official power output diagram, the 255 HP one (that in reality were 230, i think no car had 255 hp, maybe they tested it without the airfilter and muffler).


ciao
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My Vetro (full euro-spec dry sump) was dyno'd after a full rebuild of the engine, of course after running-in miles. The engine is completely stock spec, only with "oversized" pistons due to the overhaul/re-bore, I don't know the correct translation but I'm sure you'll understand.

Can't post the diagram right now: new laptop & I can't find the CD with software from the scanner.. The runs were done on a Dynojet model 248 dynamometer by BCCP, Gramsbergen, NL. Torque (Nm) and horsepower in DIN, measured at the wheels.

RPM/Torque/HP :
2000 199,0 55,9
2500 212,9 74,7
3000 223,2 94,0
3500 237,9 116,9
4000 242,9 136,4
4500 244,5 154,5
5000 246,7 173,2
5500 244,0 188,4
6000 233,8 197,0
6500 218,4 199,3
7000 198,7 195,3

Max torque 247,2 @ 4900 RPM, max horsepower 199,6 @ 6400 RPM.

Nice thread !

Best regards, Emile

 

MY 1980 production 308 euro dry sump Italian DOT papers say as omlogated power "229 HP @ 6600 RPM". Those datas were the result of an official test on a dyno done by Italian DOT when a new model came out.

ciao

 

When I bought the car it came with some copys of Italian documents which are for me harder to read then for you Alberto !

On a copy there is stated "pot. max CV 229 giri/1'", which of course is for maximum power 229 HP at 6600 RPM. Maybe we are talking about the same piece of paper.

When looking at the dyno results from my car, and the way the drivetrain is built, some 30 horsepower loss from crank to the wheels seems about right. The number "255 HP" should then lead to some 220 HP at the wheels, I doubt that one would ever measure such a value.

 

CV stands for "cavalli vapore" = steam horses, literally. It means Horsepower.

The 229 CV at 6600 giri/min (=RPM), the datas you read on your car documents, were measured at flywheel during omologation test done by Italian DOT when the dry sump engine was introduced on the market and were the same for all dry sump engines ever produced.

That's what papers say, no more, no less.

As I wrote in the other discussion, they are probably less than expected because during the official DOT test they had to lower the fuel air mixture ratio to meet the CO limit: less fuel, less power.

If i have to say what i felt (no measures), i would say that, comparing the cars i have (and also the ones i just drove) in the actual conditions, the dry sump is way slower than the 86-89 turbo intercooler and than the 328, but it's faster than the first 82-85 turbo, faster than the 2 valves GTBì I drove and more or less as fast as the GTS QV I drove.

As the turbo intercooler claims 254 Hp and the 328 claims 270 HP, the even lighter 308 dry sump cannot have 255 HP, or it would be as fast as the others two, and it isn't at all.

230 looks to be the real power, more or less


But the carbed is a very pleasant engine, with a great sound and a very good power.

ciao

 

Does this count? This is the one I had...pretty accurate I would say, too
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My results are in this thread.
http://www.ferrarichat.com/forum/308-328/367751-euro-308-qv-dyno-results.html

 

Some more data for you. I performed pre/post dyno runs after beta testing Dave Helms' SRI GCK on my 86' 328 (see post #5 for actual dyno graphs: http://www.ferrarichat.com/forum/308-328/408593-328-love-story-scuderia-rampante-gold-connector-kit.html). All runs performed on a Dynojet. Car is in stock configuration with the exception of GCK, Tubi exhaust, and Fabspeed cat. Pre GCK max HP 225.5, max torque 189.3. Post GCK max HP 231.9, max torque 192.3

Post GCK #'s
RPM HP Torque
3000 92 161
3500 114 171
4000 133 174
4500 154 180
5000 176 185
5500 200 192
6000 216 190
6500 228 184
6865 232 178
7000 230 173

Max HP 231.9 @ 6865rpm
Max Torque 192.3 @ 5575rpm

 

Is this printout acceptable?
Originally a. 3.0 QV
360 crankshaft
Haltec ecu
EFI
Custom cams
Custom oversize Pistons
Custom oversize valves

 

Admittedly I am on my phone, but I cant read the numbers. Can you post those (although they are probably posted elsewhere on the forum).

I am fascinated with all you have done with your car of course.



PDG

 

I am on the phone as well. The numbers are visible on a laptop or desktop computer I think. If not I have the actual printout somewhere.
Found it: sorry I have reversed HP and Torque columns

Mustang Dyno

RPM Torque HP
2831 165 90
3412 172 111
3996 193 150
4579 194 172
5162 200 200
5744 210 230
6327 205 250
6910 197 263
7493 187 270

Eng Torque T WC (Ft-Lb) 213
Eng Power T WC (Hp) 270

 

Does this make any sense? If so then my graph doesn't really show true against the others ;
It all depends on the dyno and how it is reading and computing the power / load ratings. There are "inertia" dyno's that give a particular number, and there are "load" dyno's that give an entirely different number. Why do they do this you ask? If you took a typical DynoJet dyno (chassis dyno) and ran a car on it, it would give you a given number based on inertia and the spool-up speed of the drums. If you took that same car and put it on a Mustang Dyno or SuperFlow "load" dyno, you would get a much lower number simply because they are measuring power under different circumstances (under a load).

There is typically a 140 or so HP difference between an inertia dyno and a load dyno. Then you have to take that number and divide it by .85 to get the close approximation of power at the flywheel. Now, some people will argue about the .85 number and say you just need to figure on about a 60HP loss through any typical chassis, so you simply take the rear wheel power number and add about 60 to it and you'll be in the ball park, but most dyno shops will tell you it is an average of 15% - 18% loss through the chassis (on average). Well, .88 to .85 IS 15% - 18% when you are doing the math.

So let's say you have a 450BHP engine (at the flywheel), that would be about the same as 380 RWHP on an inertia chassis dyno. You typically lose about 15% - 18% through the chassis, so 380 divided by .85 = 447HP at the flywheel (basically 450HP). Now, with a "load" chassis dyno, you will typically have about 140 LESS power than you would with a "non-load" (inertia) type of dyno. So take that 380 at the rear wheel and drop that down by 140HP, which comes out to 240 RWHP under a load. So, 240HP under a load 140 variation HP = 380 basic RWHP, now divide that by .85% and you get approximately 447HP at the flywheel.

Your car made 290 RWHP and you blew the doors off of two new Vette's which are quite powerful cars and run fairly easy 12 second quarter mile times. 290 HP isn't enough to run 12's in the quarter mile, not even with a hurrican for a tail wind, so I have to assume that your 290HP was a "loaded" HP reading. If it wasn't a loaded reading, then your engine was only making 341 Flywheel HP (BHP) and that just isn't a number that is very capable of blowing the doors off of two new Vettes, so it had to be a loaded number.

So, 290 RWHP under a load, plus the 140 variation you normally have between inertia dynos and load dynos = 430 non loaded RWHP. Take that and divide it by .85 and you are making in the neighborhood of 505 BHP (at the flywheel).

Just for the sake of argument, some people say to only add 60HP to make-up for the loss through the chassis. OK, then you take your 430 non loaded RWHP and ad 60 more to it to compensate for chassis loss and you come out to 490BHP. That is pretty damn close to the number you get when you divide by .85. Which one is more accurate? Honestly? I don't know, (and couldn't know), unless we first dyno'd the engine and then stuck the engine into the car (making NO tuning changes or modifications) and running it on the chassis dyno and seeing what we got as far as a difference between the engine itself and the loss through the chassis.

 

So I took the 140-60=80 and corrected the Mustang numbers:
170
191
230
252
280
330
343
350
This should better correlate with the other curves.

 

Emile,

Three quick remarks from me, if I may;
-I always had in mind that the empirical formula you use "in your head" to quickly find the horsepower loss form crank to wheels is 16 to 17%; it matches your figures.
- I won't go into details about the actual power of the Ferrari V8 through its different versions, as much as already been written about this, and this is not a new subject; but my guess is that as you are from the Netherlands, there is a good possibility that you read german (?).
Should it be the case, then get a copy of "Autos, die Geschichte machten: die Ferraris 308 und 328" by Dirk-Michael Konradt (Motorbuch Verlag 1990).
In the main of the text and also in the annexes are the results of the tests by the German TÜV on the different variants of the engine, when the cars appeared on the market: if my memory serves me well, these were 235 hp for the wet sump engine of the 308 GT4 and 229 hp for the dry-sump carbed V8.
- When the french magazine "Sport-Auto" had its first road test of the then new "Vetroresina" in the spring of 1976, the figure for the power of the engine given is once, and only once at "255 hp"; then in the text it is always said: "230 hp".
255 was probably obtained using SAE figures, but at the time, most people were aware that the "true" power of the engine was 230 indeed.

Of course, Ferrari knew those figures very well, but they didn't do anything to clear the confusion; they knew also very well that the true weight of the "Vetro" was 1240 kg (which is the exact figure that is on the official certificate of homologation they made with the Italian Ministry of Transportation) but some marketing brochures were nevertheless quoting “1150 kgs” and some even quoted “1090kgs”. They didn’t do anything to clear that confusion either.
Why? Because it was more advantageous to let some people believe that the figures were 255 bhp for 1090 kgs, rather than say these were 230 bhp for 1240 kgs (which were the true figures…have a look at the certificate of homologation, which is accessible on the net )
This is how legends are born; and some still survives to this day, because you will still find today in a lot of publications that a “Vetro” has 255 hp for 1090 kgs…

Rgds

 

Correct, Bruno. No carbed V8 cars went out from the factory with 255 Hp (DIN measured). None weighted 1090 kg. The 8,8 compression ratio euro carbed engine (dry sump) has 229 CV @ 6600 RPM, those are the only true homologated data. The wet sump has two or three more CV (hp) due to the saved loss of "pompa di recupero" (oil draining pump), that the wet sump hasn't.

The dry sump system wasn't intended to gain power but to be better suited for track days with no oil emulsion, no oil pump cavitation, no dry working at high revving, all problems you could have with a wet sump at high revvs and high g forces, a conditiond you can have in a race track or similar use.

USA cars have less power and MUCH more weight.

The 255 HP were CUNA measured (that gave usually a 12-13% more power, due to water pump and alternator disconnected). 229 x 1,13= 258

All the official and homologated power were DIN.

End of story.

ciao

 

I absolutely agree Alberto; I was only trying to explain why those figures (255 hp / 1090 kgs) are still quoted by some today.

Rgds

 

I think we could write a book about those cars. You know more things than me but i know more cars: let's do it!

ciao

 

@ Nerofer: But of course you may !! After importing the car in 1995, and the scrutiny for the dutch license plates the car was weighed and the scales hit 1270 kg, which is stated in the dutch license documents. When I took the car out for a testdrive back in 1995 my first thoughts were something like "oh oh, it's not exactly very fast..", the Alfa Romeo Alfetta GTV with 3.0 Busso I drove those days wasn't slower, not for a bit. And compared to my current daily driver (Alfa Romeo 156 GTA with lightly tuned engine, 287 HP/335 Nm, 1385 kg) the Vetro doesn't stand a chance in whatever circumstances. On the Dutch "Circuit Park Zandvoort" track (4,4 km length) the Vetro is some 5 seconds slower than my trackday Alfa Romeo Giulia Super (180 HP/210 Nm/910 kg) Of course the Alfa's are no match for the Vetro when atmosphere and charisma is regarded. I would lóve to have an extra engine tuned to some 300+ HP, keeping the original engine should I ever decide to sell the car. It's just that I don't have unlimited resourses, how annoying..

Thanks for the tip ! I speak German on a daily basis, so no problem with reading it at all.

Cheers, Emile

 

warmed up 105's are a boatload of fun on the track. not a lot of people published street drive 308 laptimes for good reason!

 

The differences are a bit more complex. First thing we need to understand is that comparisons between dyno's are apples and oranges. So many variables in play make it nearly impossible to compare them.

Dynomometers measure velocity and force, or velocity and time. Not a single one can measure torque directly, indirectly yes. Then power is calculated. There is one dyno that is a bit odder in that it calculates power then back calcs torque.

Inertia dynos like the dynojet use a known mass (the drum) and use dv/dt to calculate the torque and power needed to accomplish that. The mass of the drum can be a problem for the vehicle depending on the weight delta between them. Also where the tangent contact point is between the wheel and drum will affect applied power. as does tire pressure, low pressure will induce more losses. This type of dyno is still a load, but it's only useful for WOT runs, the dv/dt can't be calculated when the velocity or v does not have a delta. But it's still a load to the engine.

Strapping of the vehicle also creates spurious readings, best case scenario you only want to hold the vehicle from moving past the roller. When they strap and pull the vehicle down onto the rollers it reduces the measured power.

Eddy current and constant load dynos are different from inertia dynos in that instead of a large known mass there is a reactive load applied to the drum roller to measure power. How they measure power is different. a strain gauge is used, however a strain gauge only measures force. either in N (newtons) or Lbf (pound force) This force would be the same as you stepping on a scale. It can be also called tractive force. I'll try and keep it simple by leaving out the vectors and scalars of the physics involved. So by now having the applied force to the strain gauge the power can be calculated.

With all dyno's having the engine RPM is not needed to calc the power. All calcs are done first in relation to drum velocity. Now one dyno brand uses the linear velocity and not the angular velocity of it's rollers to calculate the power output. I have picky issues with that. That brand is the dyno dynamics and also why in my opinion it reads lower than all the dyno's. The dyno jet inertia dyno is the closest to trap speed HP calcs one can get short of the drag strip as long as your vehicle weight is very close the drum weight. Other wise you'll get incorrect data for obvious reasons, esp turbo engines as load is directly related to boost development.

Eddy dyno's run into issues with 'ramp rate' that is the load applied over a fixed period of time to measure the power output. As we can see that would require knowing the exact gear ratio and losses thru the drive train to properly load the engine for an accurate measurement. I can't think of a single dyno operator or shop that goes to that trouble. so est are used developed by the dyno mfg or in some cases it's a fixed amount for all vehicles that roll into that shop. This is applicable to WOT power pulls. For steady state tune the strain gauge is a valuable output for seeing in real time the effect your changes have. being a vector-less number keeps confusion down as well. (more on why in a bit) However to be the most accurate the load applied to the engine during that steady state requires matching drivetrain losses and air resistance at that speed that the vehicle would actually have. once again that's not easy. So est are used.

The force measurement of the eddy dyno if you can get it displayed in real time is most useful as it's not having to back calc torque to the roller. Strain gauges are highly sensitive and thus can measure force in very minute amounts very quickly.

---- breaking into a second post----

 

Hi Scott. Always enjoy your in depth contributions. All this is very interesting but it doesn't help me try to verify my normalizing effort on my numbers to try and help them correlate better to the Dynojet numbers for comparison. In your opinion what should I use as an approximation?