Enzo Posted August 1, 2006 Posted August 1, 2006 I just got back from a long session to have a custom map made for my V11 'Cobra.' I have never actually had a proper map for this thing. Boy, it was running terribly and the map was WAY rich. Just swamped in gas. Anyway, I pulled 89 back wheel horses and 68 pounds of torque on a good level chart. Is there a place on this site to look at other dynos?
Enzo Posted August 2, 2006 Author Posted August 2, 2006 Enzo's Cobra with Two-into-One Enzo replica top end racing piple - Mark Seven:
Enzo Posted August 2, 2006 Author Posted August 2, 2006 I don't like how the torque falls off at 6300. I'm making a couple small adjustments and a possible big experiment. It may be good and it may be a disaster. I'm going to go back in to have another pull when my mad tweeking is done. I want to see 90 hp. Here I'm at 89.1 and it killed me that I couldn't reach 90. At least the torque goes over 60 and stays up there till about the end. Stay tuned......
guzzi jon Posted August 2, 2006 Posted August 2, 2006 Still the best torque curve I've seen on one of these.... Mods that move the torque curve up could kludge the power down low, sure looks sweet where it's at. Breaking 90 should be easy with a bit o fiddlin I don't like how the torque falls off at 6300. I'm making a couple small adjustments and a possible big experiment. It may be good and it may be a disaster. I'm going to go back in to have another pull when my mad tweeking is done. I want to see 90 hp. Here I'm at 89.1 and it killed me that I couldn't reach 90. At least the torque goes over 60 and stays up there till about the end. Stay tuned......
Baldini Posted August 2, 2006 Posted August 2, 2006 Enzo, aside from exhaust what other mods are in the bike? Curve does look nice. KB
Enzo Posted August 2, 2006 Author Posted August 2, 2006 Thanks all...... It has the FBF 11:1 pistons. K & N filters with no air box, Pete Roper's sump tray. That's it - well, my Cobra pipes. My dyno guy thought that the tube between my air filters and throttle bodies were a bit long and that I could possibly get more top end with a shorter tube, so I picked up new foam pod filters that don't even have tubes. We also found that my bike actually runs better with the old Mistral can placed back on it. We ran it wide open, we ran it with my 'cone' end piece, and we ran it with my old Mistral placed back on. The best results as you can see are with the much longer system with can. Good news for the sound. I was getting tired of all that racket. I'm having the can welded in place today. I'll send pics later, but now the entire system is quite long - longer than stock I think. This is weird because I still get very good top end. But playing with pipes is a black art.
Skeeve Posted August 2, 2006 Posted August 2, 2006 I don't like how the torque falls off at 6300. I'm making a couple small adjustments and a possible big experiment. It may be good and it may be a disaster. I'm going to go back in to have another pull when my mad tweeking is done. I want to see 90 hp. Here I'm at 89.1 and it killed me that I couldn't reach 90. At least the torque goes over 60 and stays up there till about the end. Stay tuned...... I wonder if the PHAAAT bottom end & torque peak @ lower rpm than stock [check the dyno charts thread; seems like V11s torque peak is above 7k rpm, the cruiser/CAs being down around the 6k you're experiencing...] are related to the Cobra's merging on the right vs. the Griso pipe's left-hand merge, ie: the Cobra has a longer header for the left cylinder vs. Griso has longer rt. side exhaust tract. Due to the Guzzi firing order, this subtle difference could have a profound affect upon the resulting powerband. No offense to your efforts Enzo, you know I've been very interested in & respectful of your experiments, but you'll have to excuse my suspicion that the Guzzi factory engineers know more about this topic than you, & would be trying to milk the most h.p. out of the stock configuration for the Griso (if only because their continued livelihood depends upon the factory selling a lot of Grisos!) and so made the choice to run the 2->1 collector on the left side of the bike for that reason. Neither the Cobra pipes nor the Griso have equal length headers, the way the Dr. John endurance racer replica pipes have [pics of which I've seen elsewhere on this site in old threads.] Clear as mud? Trust ol' Mr. Gizzard to 'splain things as obfuscatingly as possible!
Enzo Posted August 3, 2006 Author Posted August 3, 2006 The two Cobra headers are the exact same length going to the collector so it doesn't matter what side of the bike they collect. My new pipe is very long. It now collects on the right side - RUNS UNDER THE BIKE TO THE LEFT SIDE - and then under foot and 45 degrees out to the rear. This set up is several inches longer than stock. As for stock headers and design - it is VERY expensive to twist pipe in a fancy way. Much cheaper to put out a single curved header pipe and then straight to the back. If Guzzi wants or needs to make more power, they will have to spin the engine faster or go to their own variable exhaust system. I don't know what the Griso puts out. Is there a dyno on the Griso I could look at? Also, I can't find the dyno thread on this site. Can someone give me a link? I'd like to study them.
Skeeve Posted August 3, 2006 Posted August 3, 2006 The two Cobra headers are the exact same length going to the collector so it doesn't matter what side of the bike they collect. My new pipe is very long. It now collects on the right side - RUNS UNDER THE BIKE TO THE LEFT SIDE - and then under foot and 45 degrees out to the rear. This set up is several inches longer than stock. As for stock headers and design - it is VERY expensive to twist pipe in a fancy way. Much cheaper to put out a single curved header pipe and then straight to the back. If Guzzi wants or needs to make more power, they will have to spin the engine faster or go to their own variable exhaust system. I don't know what the Griso puts out. Is there a dyno on the Griso I could look at? Also, I can't find the dyno thread on this site. Can someone give me a link? I'd like to study them. Don't have a Griso dyno chart; from reports, I just don't expect them to have the flat, flat torque curve your Cobra is putting out. I guess the "different length" headers is just an optical illusion; better look for the answer somewhere else then... The Dyno Gallery thread is here. Yes, more power = spinning the motor faster or having higher BMEP. Shorter stroke & lighter valvetrain components allow the former; more valve port area might get you the latter, but it requires keeping the intake velocity up: that's where the valve overlap & a proper 2->1 header design comes in! Kudos on the results you've managed from the Cobras, Enzo. Don't fall into the trap of going snorkleless on the sock filters: air doesn't like turning sharp corners! Ride on,
rocker59 Posted August 3, 2006 Posted August 3, 2006 No offense to your efforts Enzo, you know I've been very interested in & respectful of your experiments, but you'll have to excuse my suspicion that the Guzzi factory engineers know more about this topic than you, & would be trying to milk the most h.p. out of the stock configuration for the Griso (if only because their continued livelihood depends upon the factory selling a lot of Grisos!) and so made the choice to run the 2->1 collector on the left side of the bike for that reason. Neither the Cobra pipes nor the Griso have equal length headers, the way the Dr. John endurance racer replica pipes have [pics of which I've seen elsewhere on this site in old threads.] Clear as mud? Trust ol' Mr. Gizzard to 'splain things as obfuscatingly as possible! Both Enzo's Cobra and Dr. John's 2:1 have equal-length headers, if I'm not mistaken. Keep in mind that the factory has more parameters to deal with than just dyno performance. 1) Cost of production. 2) Ease of assembly. 3) Noise emmisions. 4) Exhaust emmisions. 5) Aesthetics. 11:1 pistons in a factory Guzzi would worry the hell out of the warranty department. Neither the Cobra or Dr. John pipes could meet Euro 3 or DOT 85db. I submit to you that the Griso's left-side exhaust was an arbitrary decision made by Marabese, or whomever penned the original concept. The Griso's un-equal length headers are strictly due to styling and cost/ease of production issues. And, the Griso's exhaust kink is a packaging issue brought on by having to plumb around the footpegs and lower frame while keeping the exhaust can on the same side as the headers...
Enzo Posted August 3, 2006 Author Posted August 3, 2006 That link you've given me goes to Wildguzzi and a small conversation about the Griso. Still looking for a link to some V11 Dynos.
guzzi jon Posted August 3, 2006 Posted August 3, 2006 Enzo, On this site there are a few posted http://www.v11lemans.com/forums/index.php?showtopic=8556
Skeeve Posted August 3, 2006 Posted August 3, 2006 That link you've given me goes to Wildguzzi and a small conversation about the Griso. Still looking for a link to some V11 Dynos. Sorry 'bout that; it's been corrected. Bad copy & paste...
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