| Author | Message | ||
     Boarman |
Hi I had a 1997 buell s3t, but unfortunately some guy in a truck decided that i didnt need it anymore and destroyed it along with my wrist and knee. luckily the engine survived the crash. I also have a 1998 sportster that i put a 1996 s2 motor in. from what i understand the s2 motor is really nothing more than a stock evo motor, so i was going to put the heads and cams from the 97 s3 motor onto the s2. my question is if i do this is it going to make a difference, should i put the whole jug on, and basically what is the difference between the two motors? any help would be great thanks. | ||
| Sportyeric |
The heads that you have on the S3 are what were marketed as Screamin' Eagle performance heads in 1995, so they were at that time, supposedly worth spending $600 for the improved performance. They are now called Lightning heads, as they were stock on the S1 Lightning and the S3 in 97. Those bikes were rated at 91 crank horsepower. I think the S2 was rated at 76, half the difference being cams, the other half heads, IMHO. The chamber design allows a 10:1 compression ratio, rather than the 9:1 (or maybe 9.5:1?). However, compared to the Thunderstorm heads which came after, they don't flow well at high rpm. I've had just that head and cam set-up on my Sportster for years and I really like it. My stock S2 is really limp in comparison. I could win roll-ons anywhere from 3000rpm to 5500 against a stock 2000 M2 in spite of a 100 pound weight difference (the Sporty and my fat ass.) | ||
| Boarman |
ok, thanks alot for the info. I am definately going to switch over those heads and cams. | ||
| Sportyeric |
You'll want to use the S3's ignition module too. | ||
| Boarman |
i was gonna put something aftermarket on it, like a crane | ||
| Boarman |
also i was gonna use an s&s e carb | ||
| Sportyeric |
Ssounds like fun. The S&S carb will give a different throttle response than the CV. I've grown used to the stocker. Aftermarket ignitions seem to me to be extravagant for what they add to the mix but then I'm really cheap. My bike has the VOES modified to activate sooner. And a Screamin' Eagle coil (but that was a freebie.) I posted this Lightningstorm heads a while ago, describing my build plan. Still stalled out on it, but soon. (Message edited by Sportyeric on March 30, 2007) | ||
| Jimidan |
I have read dyno studies done by Aaron Wilson on aftermarket ignitions for stock motors, where he says that unless you engine is fairly modified, you get no increase by using them. It makes sense to me. See his study on his Nallin Racing web site. I have a Crane on my S2 with highly modified 88", and I do get some benefit. If my engine were stock, I would use the stock ignition though. The S&S carb will not give you any advantage either...and may be worse. They are really simple carbs that were more suited to the Flintstone's car than to your motorcycle. The throttle response of the CV is noticeably better. Keep the CV and buy yourself a set of nice tires! jimidan |
