Video - BamaChips 91 Race Tune - Awesome!
10/20/06, 10:02 PM
#61
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The idea of sacrificing power for torque doesn't make a lot of sense. The engine is going to make max horsepower with a specific combination of AFR, ignition timing, and cam timing at a specific rpm. Whatever torque/power it makes at 4500 rpm has nothing to do with what it produces at 6000 rpm. If you look at a typical ignition curve, timing at full throttle advances starting at ~1500 rpm, maxes out at ~2500-3000, and stays the same up to redline. This is a generalization going back to the days of distributors and carburetors, but the principle still holds true. Cam timing has a huge effect on power production. Advancing the cams favors lowend torque whereas retarding them improves high rpm power. Since our engines have VVT we get the best of both worlds-advanced cams at low rpm and retarded cams at high rpm. You don't have to choose one over the other. The other variable is throttle opening. The faster and farther the throttles open for a given gas pedal movement, the faster the car feels. I suspect that this is what Doug does with the Race tune. The car FEELS faster because the throttles are opening farther and more rapidly with a given pedal movement. However, I suspect that if you dynoed both tunes there would be no difference in horsepower. BMW does this on certain models. I had a 2003 Z4 3.0 with a "Sport" button. In Sport mode the throttle response was much quicker and the car felt a lot faster, at least at part throttle. All the sport button did in reality was increase the rate of throttle opening, creating the illusion of more power. It felt way better and was much more fun to drive in Sport mode, but it wasn't actually faster. Regardless of what Doug calls it, the Race tune makes the car even more fun to drive.
10/21/06, 06:36 AM
#62
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I think the deciding factor for most (and me) was the fact that Doug will e-mail you your tune if it needs any adjustment from adding/deleting a mod. Where as Brenspeed, you'll have to send your XCal2 unit in for the update. If I'm wrong here, please let me know. I just compiled this info based on what I've read in this forum.
10/21/06, 03:13 PM
#64
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Well, I now have new respect for the perf tune. On the way home tonight I started playing around on the wet roads and as long as I kept the RPM's up, it took no effort at all to make her fishtail... at ANY speed.
The perf tune really makes me see how much the tq tune takes the 4.6 in the direction of a pushrod V8. I think of it like this. If this was a scale or a spectrum, put a high pereformance Honda at one end, a 5.0L at the other end, and a stock 4.6L 3v right in the middle. The tq tune moves the 4.6L over towards the 5.0. Not all the way TO the 5.0, just towards it. The perf tune takes it towards the high reving Honda. Feels almost stock in the low RPM's, but get 'em up and it can be just as much fun (and just as dangerous) as a 5.0.
I'm guessing (and hoping) the Race tune will almost be a combination of both tunes since a 5.0 takes a little finess with the gas pedal compared to a 4.6.
Sorry for the long winded post. Had a little time to think on the drive home.
The perf tune really makes me see how much the tq tune takes the 4.6 in the direction of a pushrod V8. I think of it like this. If this was a scale or a spectrum, put a high pereformance Honda at one end, a 5.0L at the other end, and a stock 4.6L 3v right in the middle. The tq tune moves the 4.6L over towards the 5.0. Not all the way TO the 5.0, just towards it. The perf tune takes it towards the high reving Honda. Feels almost stock in the low RPM's, but get 'em up and it can be just as much fun (and just as dangerous) as a 5.0.
I'm guessing (and hoping) the Race tune will almost be a combination of both tunes since a 5.0 takes a little finess with the gas pedal compared to a 4.6.
Sorry for the long winded post. Had a little time to think on the drive home.
10/21/06, 03:36 PM
#65
Team Mustang Source Legacy Member
Why couldn't you make a tune that had the Torque under 3000 and all out race tune acceleration for 3000 and up because anytime i'm above 3000 i'm pretty much going to want all the throttle response and power i can get. Seems like you would have the best of both worlds? I'm wondering as to why we can't have both in one tune?
I don't think that's right. I just got back a few responses from Brenspeed about purchasing a tune. It's a little pricey since I didn't buy a tuner from him, $110 for a single tune. I haven't done it yet but was thinking about it just to have a different one. Also since I have Airaid CAI Brenspeed say they prefer the MVT tube removed which utilizes the entire 4" diameter tube. Brenspeed says they got more power out of it that way so I was thinking of trying it at some point. So as far as I know I could call them, give them the specs and he'll send me a tune for $110.
10/21/06, 05:32 PM
#67
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Well that's what Bamachips also said but Brenspeed said they *did* get more power out of it with MVT out so I might try it out for the heck of it.
10/21/06, 09:00 PM
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10/21/06, 09:14 PM
#70
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