Citroen SM/Maserati dyno figures

I stumbled on this video on youtube today and thought it yielded some interesting numbers. The engine is a newly rebuilt stock Euro spec 3L Maserati V6 with dcnf carburetors in a Citroen SM being tested in a Dutch shop. The dyno pulls were around 175-176bhp at the wheels which translates to about 205bhp at the flywheel (approx 17% transaxle loss factored). The best pull was 182bhp after jet tuning (not shown in video). Maserati rated this engine at 190bhp at the flywheel in the non-SS variant which could conclude that Maserati was far more honest in their figures regarding this particular engine than that of their Maranello neighbors. Keep in mind that a stock carb 308 engine pulls the same figures but of course Ferrari claimed far more power than that. This being the case, I would not at all be surprised if a stock Merak SS engine produced near 200bhp (220bhp at the flywheel) at the rear wheels considering that vast modifications made to that particular engine when compared to the earlier which would be in line with Maserati's claims.

So for the first time I have personally seen, the Merak SS engine in its stock form appears to be greater than that of a 308 engine in any of its stock variants. This also helps to support that Maserati's bhp claims were more forthcoming than others at the time.


http://www.youtube.com/watch?v=3xgyd3-24ew&feature=related

 

Very interesting and certainly a good find!
It is interesting to cross compare contemporary 3 liter sports car outputs. The 1979 911 SC, also a 3 liter engine strangled by K-jetronic, initially was rated at 180hp, later upped to 188. FChat sponsor Carobu essentially stock blueprinted a 1974 308 GT/4 engine and on the engine dyno got a best output of 234 hp, while Ferrari claimed that engine was good for 255 - I would imagine most factory engines were below Carobu's 'perfect engine' power. Most US K-jetronic 2v cars do rear wheel dyno around 170, suggesting flywheel numbers at 17% loss at around 200 hp. Of course, while it is always dangerous to cross compare rear wheel dyno numbers, I've seen some tired 3.0 QV Dyno-jet near 180 hp.

As hard as it is to believe, Lamborghini was claiming 260+PS from their 3 liter Urraco, but subsequently downrated the 3.5 liter Jalpa to around a more believable 255.

I'd agree that the Maserati claims are more realistic and believable. A solid 200 hp with torque, and certainly anything above, are good numbers for engines fighting those contemporary emissions standards with the available technology.

It's been my experience that Ferrari dyno vs factory claimed numbers did not start getting close (i.e. more truthful) until the late 80s when dynos became more prevalent on the open market. By the 3.2 liter engine, the factory stated and actual dynos were pretty close.

 

not a direct link but check this P300 out.... maybe 220-235 whp? all dyno's are different of course....

http://www.lamborghiniregistry.com




1976 Lamborghini Uracco P300
Chassis #20342
Engine #20342
Built Oct 1976

This car was purchased new in November 1976 by Walter Zambelli of Palestro Italy. Rein Vosari of Conneticut, USA purchased the car from Classic Cars Co. in Milan, used it in Europe and then brought it to the US in 1984. It has had the suspension modified to run Yokohama 008R tires which can be seen in the photo above. The current motor is heavily modified and has been dyno'd at 282 HP. It is in very good original condition other than extensive mechanical modifications /improvements. Currently in Connecticut, USA.

Check out photos of the rebuild of engine #20342done by Rein Vosari of Connecticut Classic Cars.

 

The only 308QV I have seen dyno'd was a Euro version and it was in very decent shape. Definitely not a newly rebuilt engine, but very servicable still. It yielded 188rwbhp which is great IMO.

As for the Urraco, I have only heard anecdotal evidence about those engines being dyno tested and nothing concrete. Would love to hear about their figures at the time.

Being a former Porsche owner and fanatic turned Ferrari fanatic (sorry Pelican Porsche guys), I know that Porsche quoted their bhp figures as a minimum number rather than a maximum or median number. My stock '86 911 Carrera yielded 199rwbhp which was more than factory claims. The engine had 90k miles on it so I can only imagine that new figures were possibly 8-10bhp more than what I had tested. Funny thing is, my '76 308gtb feels much faster than my 911 all day long even though it probably isn't.

I owned a Merak SS for a while and kept the engine stock most of the time I had it. I had driven 308QVs before getting into the Merak SS, but the power delivery between the two cars was incredibly different. The Merak engine was tuned to be more of a 'stump puller' in that it had a considerable amount of torque available much lower than that of a 308 engine. There was definitely more neck snapping going on, but I could feel the power cut off right around 6300rpm. The Ferrari power started at a bit higher rpm and pulled smoother to a higher operable rev range. The difference was the Ferrari felt like it would rev forever because the power didn't just fall off a cliff as in the Merak. The Merak SS definitely felt a little faster because of the torque though. I wish I still had one I could stick on the dyno so I can settle this inner battle I have going here. I find it impossible to compare the two engines to my current GTB because of how different they all are.

Perhaps someone on the forum has a Merak ss they will dyno test for historical purposes ?


For those of you who have never heard this strange little 90 degree Maserati V6, there was a great video made showing a bench running of this engine as well as tips prior to starting a freshly rebuilt engine (it is mostly informative tech tips but wait to the end). The revving sound at the very end of the video is quite impressive! Undoubtedly a close second place sound-wise to a Dino V6. http://www.youtube.com/watch?v=XDWkx-XNpHc

 

Just send me the $. My account is in Bermuda. LOL

Ciao,
George

 

http://www.youtube.com/watch?v=WkqbTIM5RbI

140 whp for this euro spec 2.5.... wonder wat the de-tuned usa specs did?