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Originally Posted by Patrick Olsen,Nov 7 2004, 12:51 AM
The S2K ... develops little to no torque...
I agree with you Pat, the S2000 has little to no torque... compared to cars with turbo's, superchargers or larger displacements. We now live in a world where people get this silly idea that STI's are torque monsters (just kidding) since my idea of a torque monster comes in a shape of a blown crate-motor Hemi sitting in a Cuda riding on a Dana rear-end. We're talking old-school.
While I wondered about this also a very long time ago, I can't think of any car packing a motor 2.0L or less with no help from boost that has more torque (and hp ) compared to the S2000.
I'd like to see what your Mustang is all about though... those suckers can be damn quick!
Great explanations on pretty much everything Jimmy. I also was wishing that we had a way to regulate everyone's ECT's. I was very shocked to see that Mike came in with lower numbers with his Amuse header/exhaust combo than he did with a baseline that he did 2 weeks ago. I refuse to believe that this netted him losses (4 hp)! The funny thing is that Mike's car was sitting outside the dyno shop parked for 2 hours before being strapped on, while Nate just drove in and waited less than 30 minutes to get his run, and yet had the better results by 10 hp. You would think that Nate's car would be the one that would be suffering from heat soak if any. Maybe he does have a ringer, as he is very mildly modded with only intake and exhaust canisters. I wish we had more S2000's to be able to make a better judgement.
The guys at Hypersports did a great job, and even checked our tire pressures for us. Mine was at 10 psi!!! I think Conor gave me a bum set of old rubber when we swapped since I filled them all to 32 psi when I got it from him (I'm sure it wasn't intentional). No matter, my Mugen wheels were supposedly shipped from R&D Motorsports around Sept. 17 so it should get here anyday now...
Pat, coming from an AWD guy, I'm surprised at your comment on drivetrain losses.
I've got to say something about Puugee's car... IT ROCKS!! When it was on the low cam, it sounded like a normal K20A3 engine, but as soon as it hit the high cam, BAM! it really came alive. The sound was awesome! He did have some work under the hood. He mentioned the Hondata reflash, as well as some type-R cams. I'm sure there is more, as I saw other aftermarket parts (exhaust for sure), though I'm not familiar with anything other than s2k parts.
I can't wait til next week to do it again. I'm hoping to get the oil change, and throw in the IK24 plugs that Jimmy has waiting for me. I'm sure the biggest change (if any) will be the ambient conditions (particularly the humidity?) and possibly if my Mugen ECU 'learned' anything in a week (it was just plugged back in before my run, since I lent it to Mike).
In any case, it should make for a better comparison between participants in group 1 and 2.
Oh yeah, one question Jimmy. Do you think that the differing driving patterns can affect the dyno numbers? I know I've read on these forums that the factory ECU "remembers" driving patterns and adjusts the maps accordingly. IOW, if you rarely, or never VTEC your car, your ecu learns a more conservative map, and if you really hit the high cam a lot, it remembers a different map.
I don't know if it's true, but I always make sure to hit VTEC quite liberally on my way to HRP before an autocross event (good excuse, huh? ). Would this mean that Nate is a little heavy on the pedal? :: I think it might have even been UL who mentioned that, though I would have to dig into his old posts to be sure.
Speaking of UL, since he rarely posts useful information anymore, I think you should be the next UL. Let's chip in and get Jimmy a dynapack and a shop!!
Hmm, I can't say I've ever heard any difference between FWD and RWD. A gear set is a gear set, it doesn't really care which way (directionally) the power is going. So a FWD car goes engine-clutch-tranny-diff-CVs-wheels, and a RWD does the same thing but with a driveshaft added in there. In either case, there are 2 gear interactions - the tranny and the diff - so drivetrain losses should be nearly equivalent. In my AWD Subaru, there are 4 - a tranny and 3 diffs - hence the significantly higher drivetrain loss. I'm simplifying, obviously, but that's the basic gist of what I've always read/heard.
As Jimmy said, though, there are so many variables that one can run into when dynoing a car that it's really difficult to say which is better or worse. There are very few examples of the same exact engine being used in FWD and RWD configurations, so getting "proof" is gonna be tough.
Pat
PS - Whenever I can get the damn thing to a dyno and tune it properly the Mustang should be in the 375rwhp range. Naturally aspirated, of course - gotta love cubic inches.
I dunno guys, I'm puzzled by my results. I really want to be there next saturday to see how the other plots come out. One thing I noticed is that my A/F curves were much closer to 13 than the other cars (I was running leaner), the other plots I saw were richer at 11 and 12. I don't have any A/F electronics in my car but I have reset my ECU every other month (for one reason or another) for the past six or seven months, which is all I figure that I might do different.
P.S. I wear size 13 shoes, my big feet can't help mashing down on the pedal. If your ever driving on Nimitz between the Airport and Pearl Harbor at about 3 minutes to seven (the time I'm supposed to be at work) you'll see what I mean.
how do you reset your ecu and will it really make a difference? i thought you only had to reset your ecu when you got new breathing mods because the car had to "learn" what to do with the increased air? it seems in nate's case that resetting the ecu was beneficial. my entire a/f curve pretty much stayed below 12 from 4k rpms on. i wonder if the 02+ ecu's run richer than the 00-01? and all this time i have been reading that the 02+ cars made a little more power because of a revised ecu...
Originally Posted by Patrick Olsen,Nov 7 2004, 10:14 AM
Hmm, I can't say I've ever heard any difference between FWD and RWD. A gear set is a gear set, it doesn't really care which way (directionally) the power is going. So a FWD car goes engine-clutch-tranny-diff-CVs-wheels, and a RWD does the same thing but with a driveshaft added in there. In either case, there are 2 gear interactions - the tranny and the diff - so drivetrain losses should be nearly equivalent. In my AWD Subaru, there are 4 - a tranny and 3 diffs - hence the significantly higher drivetrain loss. I'm simplifying, obviously, but that's the basic gist of what I've always read/heard.
Actually Pat, there's a penalty for power loss each time you change the direction of power. Here's a statement from Puma Race Engines on their products
The 2% increase in losses over front wheel drive is because the differential has to turn the drive through 90 degrees at the back axle which soaks up a bit more of the engine's power. Copyright David Baker and Puma Race Engines"
This is a rather simplistic way to do this math, however as a general rule... for each set of gears the transmission has mulitply that number by 7% (this value varies from car to car), and this doesn't take into account the power loss outside the gearbox (such as at the diff, tires, etc.)
For example, a FWD drive has 2 sets of shafts to pass power through at...
The input shaft and the output shaft
2 X 7 = 14% power train loss
In a RWD layout, you have 3 sets of shafts to pass power through...
The input shaft, the counter shaft, and the output shaft.
Ahh! So, that's your secret your high HP on the dyno. Just need to use the all purpose tuning tool. The "hammer" was a great invention and cheap. Trick is you got to know how big a hammer, where to hit and how much force is needed.
I've used the "hammer" banging technique on Chevy starters that refuse to turn over. Works most of the time.
11-07-2004, 02:36 AM
(just kidding) since my idea of a torque monster comes in a shape of a blown crate-motor Hemi sitting in a Cuda riding on a Dana rear-end. We're talking old-school. 
) compared to the S2000.
). Would this mean that Nate is a little heavy on the pedal? :
