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Thread: IT prep Whp for honda VTEC's

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  1. #1
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    Actually Greg, the discussion about FWD deducts is well under way. So, yes, you got that wrong.

    There a number of pluses and minues to the RX7 v. the Integra. There is no reason to get into them here. The process focuses on pwr/weight, which is simple and fairly repeatable.

    It is amazing to me that someone who claimed to believe so strongly in a by the books, straight up scientific "process" with no subjectivity wants a 100 lb subjective deduct.

    All cars in ITS have significant subjective advantages and disadvantages vis a vis the others. We can't account for all of them. It's not possible.

    But since making arguments for and against subjective factors invariably is based on on track results (which can of course be prettied up and called dynamics and mechanics of driving X car), let's talk about that a bit.

    1. Has there being a 100% full on Integra build? Maybe Scott Seck?

    2. That Prelude ran 2nd at the ARRC. I believe a Corrado did once as well. Maybe the lack of FWD success in ITS is simply due to the fact that no one has built a full on 100% fWD chassis and then spent the years developing it that it takes to run and front and win the ARRC?

    3. I've certainly seen ITS Integras run good consistent races at enduros, at VIR and other places. So maybe tire management by the driver is key to doing well in an ITS FWD car. Others have to manage brakes - no 240Z has brakes that last a full race at 100% performance at CMP or Road Atlanta -- or rear tires. So what is different here?

    P.S. Pretty sure Huffmaster's RX7 was the previous ITS record holder at Mid Ohio. The ARRC winning one.





    Quote Originally Posted by Greg Amy View Post
    With only 90# more weight (and significantly better distribution) and rear wheel drive, there should be zero surprise that the RX-7 "does well" versus the FWD Integras (or FWD anything, for that matter).

    Given that most of you ("you" being the ITAC) think that a 100# weight difference from process is insignificant (thus effectively equal), what you're basically saying is that you think a FWD car and a RWD car with similar power and equal weights (e.g., less than 100# difference) are adequately classed. You're wrong, of course. Those of you that believe this simply don't understand the dynamics and mechanics of driving a front-wheel-drive car.

    How's that rethink on FWD adders comin'? Bet it ain't.


    Not to diminish the 'Lude's accomplishments - I was certainly impressed - but the ITS class at Mid-Ohio, as I recall, wasn't exactly awesome. And, also IIRC, in '07 their times were only fractions of a second faster than ITA (I remember thinking the Mosers would have given the winner a run for his money). Plus, that's the 'Lude driver's home track.

    Yes, Bob, it's probable that the Honda VTECs don't get quite the numbers with IT prep that, for example, the Nissan SR20DE engine does. But, them's the breaks, that's how "the process" works. But the real failure within "the process" is that is fails FWD cars when we get to the higher-horsepower classes where VTEC happens to reside (i.e., ITS and ITR). It's an unfortunate double-whammy.

    Needless to say, I personally don't believe the "match" is "right". - GA
    NC Region
    1980 ITS Triumph TR8

  2. #2
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    Kirk, oddly enough, I rarely remember that you're on the ITAC. And when I do I'm glad for it.

    Quote Originally Posted by JeffYoung View Post
    Actually Greg, the discussion about FWD deducts is well under way. So, yes, you got that wrong.
    Good! Now start thinking about logarithmic scale (or similar ideal) correctors based on torque output (or HP, if you feel better about that) instead of subjective, linear, or step wholly-out-of-thin-air hard numbers.

    If you understand the dynamics and mechanics of FWD, then you understand why.

    It is amazing to me that someone who claimed to believe so strongly in a by the books, straight up scientific "process" with no subjectivity wants a 100 lb subjective deduct.
    Not fair, Jeff, and a completely illogical inference of what I wrote (though not surprising).

    You simply cannot pull a subjective number out of thin air and hold it up as a sacred-cow-comparison to a mathematical process based on physical characteristics of a vehicle. In addition you will note, if you care to read carefully, that I supported "the process" of weight-setting based on the engine output versus Bob's contention that it dis-serves VTEC (do a search in my post for "them's the breaks").

    But to hold the "FWD subtractor" (or RWD adder,whichever is it) as a non-arguable part of that "process" (though that piece can hardly be called a process) is disingenuous.

    All cars in ITS have significant subjective advantages and disadvantages vis a vis the others. We can't account for all of them. It's not possible.
    So we're not going to try? And basically, "go pound sand if you don't like what we decide?"

    Are you on the ITAC now?

    But since making arguments for and against subjective factors invariably is based on on track results...
    Danger, Will Robinson! Kirk...?

    ... (which can of course be prettied up and called dynamics and mechanics of driving X car)...
    Jeff, don't even go there. If you want to make personal attacks, select the "PM" button above. I can assure you that my personal experience and mechanical aptitute is FAR better at predicting results of race cars - prior to them even hitting the track - than yours.

    Regardless, and as a result of comments such as the above, I am not going to get into a pissing match with you, Jeff, primarily because I believe you simply do not understand what you're talking about. I am confident that no matter how much fact and logic I bring to the table, that you and I will not agree on this point; and I'm confident I better know what I'm talking about, both from an education and an experience level.

    If you ("you" = the rest of the ITAC) want suggestions on how to properly address this situation, feel free to ask. Otherwise I'll assume, as I have accurately in the past, that my efforts will fall on deaf ears, and are thus pointless.

    GA

  3. #3
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    Oh yes, I fully admit you have more mechanical and driving experience than me. You win that prize, hands down.

    So let me give you a little advice, from someone who negotiates, discusses, argues and compromises for a living. Think a little a bit how you say things as much as what you say, and maybe what you say won't fall on deaf ears. Because you've got a LOT of work to do in that area my friend.

    Now, let's talk about the FWD deductor. We have in IT, and in particular in ITS, balance. Lots of chassis that can win. Whether that was via blind luck with the process, or hard work on it, I don't know -- I'd like to think it was more of the latter.

    But the process -- which has proven to work -- is simplistic by nature because IT HAS TO BE. We have 300+ cars to "roughly" balance out. I would respectfully suggest that a complicated attempt to deal with power to weight in IT via displacement or engine architecture is far more likely to royally screw up the balance we have achieved than removing washer bottles, etc.

    The simple process, with as few subjective adders/deducts as possible works for this category of cars.

    Yes, I am on the ITAC and yes I'll listen to anything you say, although as I said above I'm more likely to listen to it if it is written politely and in the manner in which adults talk.

    So, give me your mathematical fix for the FWD "handicap." I'll listen. But just remember, as soon as you try to objectify a subjective on track performance issue others will do the same. Without doubt, we'll soon see folks running calculations on swept area on their brakes and asking for adjustments as a result, or calculations on frontal area and drag in an effort to get an aero deduction for their car, etc. etc. etc. etc. ad infinitum.

    But I'll listen, so if you have the answer lay it on us.
    Last edited by JeffYoung; 01-18-2009 at 12:01 PM.
    NC Region
    1980 ITS Triumph TR8

  4. #4
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    the last time this came up, it was said that the FWD "adder/subtractor" was correct for ITA, but for ITS and ITR it wasn't enough. so i actually took some time to see just what would happen, if we used the same % weight break for ITS/R as we do for ITA FWD cars.

    i took 18 popular ITA cars, and came up with an average % weight break of 2.08. going through the list of FWD cars in ITS/R, % weight breaks for FWD ranged from a low of 1.58% for the Mitsubishi 3000GT, and a high of 2.06 for the Celica GTS. applying the 2.08% to all of these cars didn't change much, with 16lbs more coming off the the aforementioned Mitsu. the cars everyone likes to complain about flowed through as follows;

    Integra GSR; -5lbs
    Civic Si; -2lbs
    Prelude VTEC; -11lbs
    GTi VR6; -7lbs
    Acura RSX-S; -6lbs
    Celica GTS; -1lb

    it appears the former champions of that arguement have since moved on to a new approach in getting what they want for their specific car, instead this time based on hp/tq. if we're forced into determining a power multiplier based on *something else* then i like kirk's idea of coming up with a formula based on specific output of the stock motor. picking something out of the ITCS that is currently thought to hit the 25% factor right on the nose we can use it as a baseline. i don't know which vehicle that is, and i think it actually makes more power than 25%.....but just for funzies i'll use the ITA Integra

    with minimal effort, i'm having a bit of a difficult time coming up with a formula that works for all cars. i took the specific output for a handful of different cars that challenge the current process like the BMW 325, Integra Type R, S2000, CRX Si, and a couple miatas and a neon thrown in for fun. if i take the % variance from "ideal" factory specific output, then devide that by 3, and apply that variance to the baseline 25% to get a new multiplier, it looks to be pretty close for the most part.

    examples;
    92 ITA Integra --- 140hp/1.8L = 77.8hp/L baseline specific output.
    Integra GSR --- 170hp/1.8L = 94.4. ((77.8-94.4)/77.8)/3 = -7.13%. 25% - 7.13% = 17.87% multiplier
    Type-R -- 195hp/1.8L = 108.3 ((77.8-108.3)/77.8)/3 = -13.08%. 25% - 13.08 = 11.92% multiplier
    Honda S2000 -- 240hp/2.0 = 120. ((77.8-120)/77.8)/3 = -18.08. 25% - 18.08 = 6.92% multiplier
    Honda S2000 -- 240hp/2.2 =109.1. ((77.8-109.1)/77.8)/3 = -13.41. 25 - 13.41 = 11.59 multiplier
    Nissan SE-R -- 140hp/2.0 = 70. ((77.8-70)/77.8)/3 = 3.34. 25 + 3.34 = 28.34% multiplier
    Miata -- 116hp/1.6 = 72.5. ((77.8-72.5)/77.8)/3 = 2.27. 25 + 2.27 = 27.27 multiplier.
    CRX Si -- 108hp/1.6 = 67.5. ((77.8-67.5)/77.8)/3 = 4.41. 25 + 4.41 = 29.41 multiplier.

    looks pretty decent, no? i'm not sure how this would flow all the way through to process weight though.

    but here's where it fails....

    BMW 325 -- 190hp/2.5 = 76. ((77.8/76)/77.8)/3 = 0.77. 25 + .77 = 25.77% adder. we all know that's no where near enough.
    Last edited by tnord; 01-18-2009 at 12:44 PM.
    Travis Nordwald
    1996 ITA Miata
    KC Region

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