I put my 99 355 on our Dynojet today as I was curious about the numbers. It's 22k miles with high flow metallic cats, no secondary cats and a quicksilver supersports exhaust. Otherwise stock. Nothing extraordinary but seems to fall in line with some of the other dyno results I've seen for these cars. RPM is cut short as there was some interference with the RPM pickup but I pulled it to the rev limiter. Image Unavailable, Please Login
Sorry i dont understand what you are saying about the RPM. Was there a problem with the Limiter or not? The 355 dyno results that i have seen range anywhere from 310-330 RW bhp. If you had a problem with your RPM limiter then you cant have a true power figure. Here are two cars on the dyno, although one is a 348 it did read 304.8 . I cant post up the dyno sheet because i am out of picture posting space. The other is a 355 at over 325 RWP. I dont think one will ever get the same results from the same model cars. http://www.youtube.com/watch?v=UWaoWoBh0fU&feature=player_embedded http://www.youtube.com/watch?v=sqeF7zR17wA
In order to get the true engine power, the transmission oil has to be HOT, and the engine oil needs to be at least very warm. The best way to accomplish this it to arrive at the dyno after a 20 mile interstate drive just in time to be loaded up and tested. Sitting around idling to get the engine oil temp up will not get the tranny oil up to temperature. If you sit around and wait for the dyno, the enigne oil and tranny oil will be sucking power fromthe results. BTW the 355 dyno results I've seen seem to be anywhere from 298-320.
There was nothing wrong with the cars rev limiter. The problem is the pickup on the dyno had interference. The coolant temp was 190, oil temp was 170. (I've been tuning cars on our dyno for the last 9 yrs on a daily basis fwiw.) As for comparison we have some results from Fabspeed which were 280rwhp, also on a dynojet. http://ferrarichat.com/forum/showthread.php?t=237938&highlight=dyno And goths car was a bit more but still in the ballpark- http://ferrarichat.com/forum/showthread.php?t=201351&highlight=dyno One thing I did notice is my car seems to make peak HP earlier whereas most graphs I've seen peak after 8k rpm. I can't be certain as I didn't test backpressure but I think the quicksilver exhaust may be a bit restrictive at high rpm. (it actually seems louder in the midrange than high rpm).
James, I know you just bought the car a while back...the earlier HP peak could be from cam timing among other things. I hope real soon to have my engine dyno set up to test these engines, the first thing on my agenda is to test "generic" cam timing vs proper cam timing. And since you have been working on dynos before, just to let others know, numbers can vary from one dyno to another depending on many variables. The main thing is to know where the numbers are, then to re-test to verify tuning and mods, as I'm sure you know. Two different operators working with the same dyno can come up with very different results.
Gary, Yes I agree on all counts. I don't have any concerns, just figured I would post the results for those who are interested. The numbers seem reasonable to me and that's what I wanted to know. If it spun up like 220rwhp or something than obviously there is a major problem. I was told the cam timing was checked during the major and I have no reason do doubt that but on the other hand after working on cars for half my life I tend to only believe what I see For now, other than addressing the exhaust I will just continue to drive and enjoy the car. It certainly feels quicker than the dyno numbers suggest.
similar to the curve I have seen on goth's car using a Dynajet. He's getting a bit more output though. Goth's car was also having some issues with the rev pick up and we figured it was interference due to those damned bundled spark plug wires running in those tunnels you gel heads have. Your car could be hitting 300 rwHp at just before cut off. Car should be warm but not too hit, or the values slip.
