IT prep Whp for honda VTEC's

[Greg Amy]

Interestingly, those numbers are about what a good ITS RX7 puts out at the wheels.

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.

What about the ITS Prelude? Ran second at the ARRCs until a rear wheel bearing failed, holds track record at Mid Ohio...seems like it's getting the job done...

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

[Knestis]

>> ...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.

Hey - don't point that thing at me, man. There's a big difference between "we're kind of stuck with current practice" and "don't think 100# makes a difference."

>>
What about the ITS Prelude? Ran second at the ARRCs until a rear wheel bearing failed, holds track record at Mid Ohio...seems like it's getting the job done...

Yeah - Danger, danger Will Robinson. One car, one track, one driver, no evidence of any controlling for other factors. Just like that kind of evidence shouldn't be support for what we DO, it should not be support for what we DON'T DO.

Gave this puzzle a little thought last night and I confess that I'm beginning to believe the "stock displacement-specific power" factor might have some value. Right now, we subjectively apply the "torque" adder (or subtractor) and I'm wondering if that ends up being a proxy value for what Bob brings up here. It's NOT a theoretical stretch to suggest what he suggests. And it could be repeatable and objective.

I still don't believe we're dealing with torque the way we might (as a possible starting value for the process) and a specific HP factor in the "IT power multiplier" might help address these differences. Note here that I'm totally cool with this consideration because it's more closely tied to engine architecture factors, and it would keep us from getting into make-model specific considerations, which is how the question here might be interpreted. (As though Hondas should be different because they're Hondas.)

K

K

[JeffYoung]

Kirk, not sure I fully understand your thinking so forgive me if I make assumptions that are incorrect.

In my view, once we move away from a strict (well, strict-ish) use of stock hp as the basis for a the process weight, and start trying to come up with a IT power multiplier that incorporates torque then we run into a huge problem: gear ratios and torque under the curve. We then have to start looking at where cars make power and torque and that to me is the beginning of a nightmare.

The stock hp X IT adder X class pwr/weight target seems to work. IT classing should be as simple as possible, and that is simple. I personally would throw out the brakes and suspension adders -- totally subjective and impossible to accurately quantify given what we can do with brakes and suspension -- but leave in the subjective torque adder as a "rough" means of dealing with the legitimate problem Bob identifies above and the FWD subtractor.

>> ...

I still don't believe we're dealing with torque the way we might (as a possible starting value for the process) and a specific HP factor in the "IT power multiplier" might help address these differences. Note here that I'm totally cool with this consideration because it's more closely tied to engine architecture factors, and it would keep us from getting into make-model specific considerations, which is how the question here might be interpreted. (As though Hondas should be different because they're Hondas.)

K

K

[Andy Bettencourt]

Greg,

Can you provide the ITAC with your statistical analysis on FWD 'adders' for our review? The more data the better.

That would be better than 'you guys never listen to me and therefor have it wrong again'. Right? Why not submit something proactively instead of telling us how much we suck because we have it wrong?

Wasn't so long ago that the ITS FWD adder was 50lbs.

[Knestis]

I wasn't proposing setting the power multipliers (as they are currently conceived) by considering torque. I was suggesting using something like Travis described - another factor in the power math - instead of futzing around with guesses about torque. This, plus a more sensitive FWD subractor might be enough to get us a repeatable, quantitative process without the big gaps we seem to fight over.

K

[JeffYoung]

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.

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

[Greg Amy]

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

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

[JeffYoung]

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.

[tnord]

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.

[lateapex911]

Given that most of you ("you" being the ITAC) think that a 100# weight difference from process is insignificant (thus effectively equal), GA

Stop right there oh quick to judge one. I've been beating that drum, running internet polls and being an general pain in the neck over this....

Things aren't perfect, and guess what, they never will be. But, we're working on it.

[IPRESS]

Tnord,
Email me and explain all this! I didn't know you had joined the "Frustrated Engineer Frat" that is such a big deal here on the IT board! Einstein would have been a mear tire changer among this group!!!

[tnord]

Tnord,
Email me and explain all this! I didn't know you had joined the "Frustrated Engineer Frat" that is such a big deal here on the IT board! Einstein would have been a mear tire changer among this group!!!

it looks a little complicated, but it's equally as archaic with the random "devide by 3" figure put in there. seems like it works for the most part.

it's a mathematical way of saying "with IT rules, you can only ever get x whp/liter, and the power adder we give you will be based on how close the factory already got to that figure.

it will take some refinement to work, because in my mind the maximum hp/L you're assuming will differ based on the basic architecture of the motor.....I6, I4, V6, DOHC, SOHC, pushrod.....etc.

[Bob Roth]

The 160 Hp Si was a Prelude, look at https://improvedtouring.com...ad.php?t=25399

[Bob Roth]

Jeremy, I think the HP calculation is where we need to look. Tell me where I can spend to make a 155 hp 1,6 VTEC motor a 175 hp motor? I can't make it rev 15% higher unless I cheat on the valve springs and port the head like a type r. Besides, the consensus is that the 1.6 intake won't flow sp unless I change the intake to type R, it won't make much difference.

Now if spending a ton of money to get to 175 means re-allign bore the block to get 12 to one compression, I think we hace a rule problem don't we. There is a reason why 100 hp to liter is an accomplishment. Bottom line is the things that help a 70 hp per liter motor have already been done on the 100 hp per liter motor.

Ps, Jeremy, remember me? I almost bought your GSR last year for endurance racing, small world huh.

[Jeremy Billiel]

Jeremy, I think the HP calculation is where we need to look. Tell me where I can spend to make a 155 hp 1,6 VTEC motor a 175 hp motor? I can't make it rev 15% higher unless I cheat on the valve springs and port the head like a type r. Besides, the consensus is that the 1.6 intake won't flow sp unless I change the intake to type R, it won't make much difference.

Now if spending a ton of money to get to 175 means re-allign bore the block to get 12 to one compression, I think we hace a rule problem don't we. There is a reason why 100 hp to liter is an accomplishment. Bottom line is the things that help a 70 hp per liter motor have already been done on the 100 hp per liter motor.

Ps, Jeremy, remember me? I almost bought your GSR last year for endurance racing, small world huh.

Your point is taken Bob. My only point is there are examples out there with cars making 25% so perhaps for the 1.6L a weight adjustment can be made, but for a couple of the other motors it will be hard to push the ITAC when they have dyno sheets to show a 25% gain.

It is a small world! How is the Type R working for you? You did by a Type R, right?

[jimmyc]

Jeremy, I think the HP calculation is where we need to look. Tell me where I can spend to make a 155 hp 1,6 VTEC motor a 175 hp motor? I can't make it rev 15% higher unless I cheat on the valve springs and port the head like a type r. Besides, the consensus is that the 1.6 intake won't flow sp unless I change the intake to type R, it won't make much difference.

Now if spending a ton of money to get to 175 means re-allign bore the block to get 12 to one compression, I think we hace a rule problem don't we. There is a reason why 100 hp to liter is an accomplishment. Bottom line is the things that help a 70 hp per liter motor have already been done on the 100 hp per liter motor.

Im not sure what dyno you use, or anything but...


If you are struggling to get 160hp to the wheels out of a B16a, i have a few people you could talk to.. The tq isn't going to be there but we have had a few 160-170whp b16a

Sure you need to do a full legal IT build to get it, but that isn't the rules falt.

Also i am not sure who you get your info from but there is NOTHING wrong with the IM on the B16a, you do know that it is the exact same one on the b18c5?

This is the same IM with IT 1" porting that can support 200whp or more on b16a and b18c5.

[jimmyc]

Jeremy, I think the HP calculation is where we need to look. Tell me where I can spend to make a 155 hp 1,6 VTEC motor a 175 hp motor? I can't make it rev 15% higher unless I cheat on the valve springs and port the head like a type r. Besides, the consensus is that the 1.6 intake won't flow sp unless I change the intake to type R, it won't make much difference.

Ok the head casting between the B16a and the b18c5 is the EXACT same, the b18c5 head was NEVER ported, hence why it was let in IT.

Torque (ignition timing, displacement, and compression ratio) are already good, and the engine is limited by valve float at over 8000. So, no surprise it realy can't be improved upon when its already 100 hp per liter. What do you expect; 125 hp per liter?? That would be a world challenge motor. Forget it.

(ps our 1.8 liter Integra Type R is 184 whp or essentially 100 whp/per literin IT trim and 109 street hp/liter per stock oem rating).


The last point is, cheating. At 100 hp/per liter, something like a type r has nothing to work with (it always has a race cam, and it is already reving to 8400 rpm); do I need to use nitrous?. Besides, if cheating is my goal,

This is two times you mention valves floating. And in the second quote you mention your B16a floats them at 8,000rpm.

I have never really heard this before, as 8,000 is the OE red line.

After reading what you ITR makes, there is something going on, either the engine build isn't up to snuff, the dyno tuning needs work, or the dyno just reads low. I'd guess it isn't number 3 though.

We have several 100% stock from honda internally, with intake, DC header, Hondata and exhaust that are making 185whp.

Have you thought about looking to other engine builders? Or even other tuners?

[Xian]

I glanced thru the for sale ads and didn't see anything that jumped out at me. Do you have a link for the car/ad? What generation/year Civic are you talking about?

Thanks,
Christian

The 160 Hp Si was a Prelude, look at https://improvedtouring.com...ad.php?t=25399

Ahhhh... gotcha. Your original post referencing a 160hp D-series VTEC engine is what I was asking about and kept throwing me off.

Agreed that the Prelude looks like a great car for the class and looks like a more competitive package than the GSR/DelSol/Civic Si.