IT prep Whp for honda VTEC's

[Bob Roth]

Assuming a build with Hondata 300 with tuning, a quality header, and suitable intake filter, any opinions on what whp are seen for the following VTEC engines. In a separate thread see below, I am saying that the present formula that assumes we can get 25% more hp kills VTEC motors (see below) which are already at their maximum.

To start the discussion I'll give you what I have seen

D16 SOHC VTEC - 160 stock,??
B16 DOHC VTEC -- 160 stock, 150 whp
B18 GSR DOHC VTEC -- 170 stock,??
B18 Type R DOHC VTEC -- 197 stock, 185 whp

Here is my comments regarding the ITR classifications.

I think a root cause of the objection of V8's in ITR is the way the committee assignes clasifications and weights using OEM peak hp. I think this really puts highly tuned honda VTEC cars that have 100 hp/liter at disadvantage when classed against less than 33 to 45 hp/liter american cars.

I have put a lot of work into my VTEC delsol, (Hondata 300, Hytech header, tuned intake, extensive tyno tuning) to get your expected 25% hp increase . I got a bit of midrange but no substantial increase of hp. The result was 150 whp at 7400. Of course from a 1.6 liter engine thats darn good. Why would I expect more? 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).

Meanwhile, take you '80's smog motor that that at 33 to 45 hp/liter, put a big exhaust, intake system, and wake up the engine management, extend the RPM/hp peak from 5000 to 6000 rpm and a 25% increase to 40 to 60 hp/liter sounds doable.

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, it would be a lot easier to start cheating with a car who puts out 40 hp per liter than one with 100 hp, come on....

I looked at the ARCC results, no honda's are entered in ITS. The beauty of the modern japanese cars is that on the engine side, they are pretty fully developed and are near IT maximum as stock. Accordingly we are fighting with a way short stick in IT against low power to displacement V8's.

I really think the ITAC should use something other than OEM power when balancing cars. It puts modern cars at a disadvantage, and it puts VTEC hondas at a huge disadvantage.

If the ITAC fixes the way that hp, is rated, I would be fine with V8's in ITR. Don't, and I think more ITR owners will feel the way that current Honda VTEC owners do about their chances to be competitive.

For comparison from Andy's notes and using his formula (IT Weight = 9.95 * (Stock HP) + 890.8), here are ITR stock power per liter

BMW 325 --75 hp/liter
BMW 328 -- 70 hp/liter
944 S2 --66 hp/liter
Maxima -- 72 hp/liter
300zx -- 79 hp/liter
Supra -- 78 hp/liter
Acura type R -- 109 hp/liter

Camaro (5.8 liter) -- 33.3 hp/liter
Ford Mustang (5 liter) -- 45 hp/liter

For some time, the IT formula has killed competitiveness of VTEC honda's. Who knows, if we let V8 cars at 33 to 50 hp/liter use the same formula as 70 to 100 hp per liter nissans, porsche's and toyotas, maybe somebody other than the Honda VTEC racers will realize how unfair the present rating system is.

Please tell me how to get to 125 hp/liter in a honda legally and I will be glad to oblige in retracting these comments.

 

[lateapex911]

Bob, this is the same post you put in the V8 thread up in rules. should we delete this?

 

[Xian]

The D16 SOHC VTEC engine was rated at 125hp... those cars are classed in ITA (1992-1995 Civic EX/Si). The later 99+ Si cars used a B16 that was very similar to what's in your Del Sol.

A couple of questions... you mention that you've put time and money into the engine build. Have you take full advantage of the porting and compression bump allowances? How about an overbore?

As far as weight, I think the cars/engines you listed are reasonably classed and weighted. The GSR has been shown to be a podium runner when well driven, developed, and fully 10/10th's built. The Del Sol VTEC, and Civic Si in ITS are both 160#'s lighter with a smaller and less torquey engine... remember "no guarantee of competitiveness".

ARRC entries aren't really indicative of anything... especially this year with the economy iin the toilet. Add to this the fact that both Ivan and Greg Amy both wrote off very strong GSR's within a few months of the ARRC and you really just don't have much of anything there...

Christian

 

[bamfp]

Since Ivan's GSR is no more. It made 178 whp and 129 wtq. I built the engine when I worked at Sunbelt. This was on a fresh engine with about 30 minutes of break in and dino oil. I still needed to do some intake and exhaust testing. I felt that there was maybe a couple more hp there. We were able to turn it 8600 rpm. It made peak power at 8200. From the few laps that I got to drive it it was like driving and ITC car. It was all about momentum. It would not accel up turn 1 at Road A in 4th. You need to be above 7000rpm all the time. This meant you had 100wtq. So the GSR is about a 20% power increase.

 

[hondaracer48]

A comment on the GSR driving like an ITC car. Yes you do have to be in the power band, which requires you to be on the gas earlier at the exit of the previous turn. But how about changing the final drive? The 4.78 or the 4.90 final drive would make the GSR a beast in ITS.

 

[JeffYoung]

Interestingly, those numbers are about what a good ITS RX7 puts out at the wheels. Maybe a bit more power and little less torque.

They seem to do fine at Road Atlanta, and everywhere else for that matter.

Since Ivan's GSR is no more. It made 178 whp and 129 wtq. I built the engine when I worked at Sunbelt. This was on a fresh engine with about 30 minutes of break in and dino oil. I still needed to do some intake and exhaust testing. I felt that there was maybe a couple more hp there. We were able to turn it 8600 rpm. It made peak power at 8200. From the few laps that I got to drive it it was like driving and ITC car. It was all about momentum. It would not accel up turn 1 at Road A in 4th. You need to be above 7000rpm all the time. This meant you had 100wtq. So the GSR is about a 20% power increase.

 

[hondaracer48]

Yeah but RX-7's are on the dark side VTEC Power baby!!! I really think that GSR's will rule ITS very soon!!

 

[bamfp]

But the RX-7 does not have 1700# on the front wheels. That is one of the differences.

 

[hondaracer48]

Yes I agree. Tons of differences to speak of, but what really matters is which car would cross the finish line first.

 

[lateapex911]

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...

 

[Andy Bettencourt]

Since Ivan's GSR is no more. It made 178 whp and 129 wtq. I built the engine when I worked at Sunbelt. This was on a fresh engine with about 30 minutes of break in and dino oil. I still needed to do some intake and exhaust testing. I felt that there was maybe a couple more hp there. We were able to turn it 8600 rpm. It made peak power at 8200. From the few laps that I got to drive it it was like driving and ITC car. It was all about momentum. It would not accel up turn 1 at Road A in 4th. You need to be above 7000rpm all the time. This meant you had 100wtq. So the GSR is about a 20% power increase.

170*1.25=212.5

Assuming 15% drivetrain loss, that is ~ 180.6whp. I think that is pretty darn close. You did good.

 

[JLawton]

Assuming a build with Hondata 300 with tuning, a quality header, and suitable intake filter, any opinions on what whp are seen for the following VTEC engines. In a separate thread see below, I am saying that the present formula that assumes we can get 25% more hp kills VTEC motors (see below) which are already at their maximum.

To start the discussion I'll give you what I have seen

D16 SOHC VTEC - 160 stock,??
B16 DOHC VTEC -- 160 stock, 150 whp
B18 GSR DOHC VTEC -- 170 stock,??
B18 Type R DOHC VTEC -- 197 stock, 185 whp

Here is my comments regarding the ITR classifications.

I think a root cause of the objection of V8's in ITR is the way the committee assignes clasifications and weights using OEM peak hp. I think this really puts highly tuned honda VTEC cars that have 100 hp/liter at disadvantage when classed against less than 33 to 45 hp/liter american cars.

I have put a lot of work into my VTEC delsol, (Hondata 300, Hytech header, tuned intake, extensive tyno tuning) to get your expected 25% hp increase . I got a bit of midrange but no substantial increase of hp. The result was 150 whp at 7400. Of course from a 1.6 liter engine thats darn good. Why would I expect more? 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).

Meanwhile, take you '80's smog motor that that at 33 to 45 hp/liter, put a big exhaust, intake system, and wake up the engine management, extend the RPM/hp peak from 5000 to 6000 rpm and a 25% increase to 40 to 60 hp/liter sounds doable.

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, it would be a lot easier to start cheating with a car who puts out 40 hp per liter than one with 100 hp, come on....

I looked at the ARCC results, no honda's are entered in ITS. The beauty of the modern japanese cars is that on the engine side, they are pretty fully developed and are near IT maximum as stock. Accordingly we are fighting with a way short stick in IT against low power to displacement V8's.

I really think the ITAC should use something other than OEM power when balancing cars. It puts modern cars at a disadvantage, and it puts VTEC hondas at a huge disadvantage.

If the ITAC fixes the way that hp, is rated, I would be fine with V8's in ITR. Don't, and I think more ITR owners will feel the way that current Honda VTEC owners do about their chances to be competitive.

For comparison from Andy's notes and using his formula (IT Weight = 9.95 * (Stock HP) + 890.8), here are ITR stock power per liter

BMW 325 --75 hp/liter
BMW 328 -- 70 hp/liter
944 S2 --66 hp/liter
Maxima -- 72 hp/liter
300zx -- 79 hp/liter
Supra -- 78 hp/liter
Acura type R -- 109 hp/liter

Camaro (5.8 liter) -- 33.3 hp/liter
Ford Mustang (5 liter) -- 45 hp/liter

For some time, the IT formula has killed competitiveness of VTEC honda's. Who knows, if we let V8 cars at 33 to 50 hp/liter use the same formula as 70 to 100 hp per liter nissans, porsche's and toyotas, maybe somebody other than the Honda VTEC racers will realize how unfair the present rating system is.

Please tell me how to get to 125 hp/liter in a honda legally and I will be glad to oblige in retracting these comments.

I hear what you are saying Bob, but how would YOU suggest on setting up a fair and equitable system that was repeatable for EVERY car??

You're very willing to say the system is broken but offer no alternatives.

Yes, the VTECs are going to have a little more problem getting off the corners that the V8s....... But also seen Greg and Jeremy's car, with almost a stock engine, when the VTEC kicks in scream by cars on the straight like they're standing still. Do you thing the Honda's can out brake the Pony cars? How about out corner? Yes and yes, right? Should they get special allowances for that?

 

[ltblouis]

6 years ago I had an ITS Delsol with B16 DOHC vtec , the engine was built by Sunbelt and dyno sheet showed HP 162 with only 115 torque.

 

[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]

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.