March 2011 Fastrack

[tnord]

132whp ties to 120 a lot better than it ties to 110. :shrug:

[Russ Myers]

K.
Throw the Pinto in with the Mustang please. Same problem with various years.

Russ

[GTIspirit]

Let me see...110 hp * 1.25 = 137.50 less 15% driveline loss = 116.87 at the wheels.
Am I right on this?

120 hp * 1.25 = 150 less 15% driveline loss = 127.50 at the wheels.

125 hp * 1.25 = 156.25 less 15% = 132.8.

Of course, the problem with dyno numbers, just like on track performance, is that you don't know if it is an 8/10ths build or a 12/10ths build.

Bob Clifton
ITB Dodge Daytona

There is also the problem of what kind of dyno was used for the measurement. Mustang Dyno or Dynojet? Then you have to decide, does the Dynojet read correctly and the Mustang reads low? Or does the Dynojet exaggerate numbers and the Mustang is more accurate? It's hard to define what's correct when at the end of the day hp can't be directly measured, it's just a number calculated from torque and engine/rolls speed. How the load is applied greatly affects the numbers, hence the very different readings between a Mustang Dyno and Dynojet.

My view is that because hp numbers are easily gamed, let the process determine a good baseline starting point then let competition adjustments come into play.

[CRallo]

132HP peak? At the wheels? From your car? On a reliable dyno? That looks like a pretty healthy number to me. I'd need a turbo to get that kind of power!!

Bob Clifton
ITB Dodge Daytona


132whp ties to 120 a lot better than it ties to 110. :shrug:

all depends on the dyno... AND it's got funky gear ratios that may or may not have been accounted for while dynoing.

[Knestis]

K.
Throw the Pinto in with the Mustang please. Same problem with various years.

Russ

Indeed. Also the Volvi (142/242), and the Fiat 124 that we dealt with at some length last year.

K

[Knestis]

...let competition adjustments come into play.

Sorry but, NO.

If you're talking about "competition adjustments" (bleah!) as are traditionally applied in the Club, defined as adding weight simply based on observed on-track performance, you are going to have a hell of a fight on your hands. The reason release of the ITAC operations manual is so historical, is that it is fundamentally against exactly that approach.

No. NO. NO.

K

[Andy Bettencourt]

I'm not trying to pick a fight w/ you Andy, but either you were on the ITAC at the time, were involved in the discussion, and know how the decision was arrived at, or you weren't, and have no basis to make a statement like that.

If it was just a general comment as to how you felt the ITAC acted, that's cool. I read it as something you were involved in.

And why would it be someone's personal opinion? Or was this another one of those things that fell through the documentation cracks?

I'm not taking as fight-picking. I'm just making a a general statement. See the facts, weigh the facts, make a vote. Easy. Each individual would have to weigh in with why they voted how on what number.

[shwah]

The Scirocco lost 100# along with the 83-84 GTI a few years ago. The weight difference between the two is a legacy.

I will say that my experience is that the low compression motors gain more than the high compression motors in the VW counterflow 8v world. I think the cars are a bit heavy still, but not triple digits heavy. Actually IMO right now I think an S-roc has the best potential at tight tracks like BHF.

[Hoof Hearted]

Actually IMO right now I think an S-roc has the best potential at tight tracks like BHF.

You and Mike kicked my ass at BHF... ...but that's more of a "dead weight" in the seat and less of a car issue.

[Bill Miller]

I'm not taking as fight-picking. I'm just making a a general statement. See the facts, weigh the facts, make a vote. Easy. Each individual would have to weigh in with why they voted how on what number.

Fair enough Andy. I misinterpreted your earlier comment to mean that you guys discussed the different ratings, did the research, and then determined which # to use, and then processed the car. I guess where I got crossed up is that I thought there would have been some kind of record as to why a specific # was selected, especially when it deviated from what was in the service manual.

Chris,

While the lower compression motors, and specifically the JH motors w/ the 'toilet bowl' manifold, may gain more than an HT or RD motor, they're not making the gains that would be required to justify the current weight. 125 chp or 106 whp is just not possible out of that motor, w/ a legal IT build. Ask any of the top shops that built those motors all through the 90's. I've got a file that's probably 2 or 3 inches thick, that was put together back in the 90's by folks like the Pucketts, Stu Brummer of BSI, etc., documenting what kind of power an IT-legal JH motor would make.

[Gary L]

132HP peak? At the wheels? From your car? On a reliable dyno? That looks like a pretty healthy number to me.

Yes... but I think they were bump-drafting. :p

[Harvey]

If we are looking at 132 at the wheels it certainly doesn't need a weight drop

[StephenB]

Yes... but I think they were bump-drafting. :p

I assume then that you agree that dyno numbers don't matter since I was not challenging the multiplier only the 120HP number. Note the past tense on that... I am no longer debating with them since the ITAC members here posted where they got that information. It is what it is.

Stephen

[StephenB]

If we are looking at 132 at the wheels it certainly doesn't need a weight drop

Not at the wheels and not done by expensive professional equipment.

Again I wasn't EVER challenging the multiplier which is why I have never submitted any of this info. It may be worthwhile for the MR2 guys but that is a completly different scenario.

Stephen

[shwah]

You and Mike kicked my ass at BHF... ...but that's more of a "dead weight" in the seat and less of a car issue.

Bill's old S-roc (now an HP car) and Bob's white one (which has not been out in a few years) are two cars I would like to spend a few weekends in out there. Just based on spending some straight away time with them and realizing what the weight difference should mean in braking/cornering. I could be wrong though...

[pfcs]

There's my favorite problem again-dubious chassis dyno data!!
Listen-in my opinion the cpe weight shouldn't go down. I base that on:
my experience (lrg) w/that family of 4/5 cyl engines and common sense;
my experience with the twins showing me their technical abilities vis a vis engine preparation was not terribly sophisticated (ie: not near 10/10)
my own experience on-track with those cars in a very well prepared/tuned/dynoed/competetive A2. (and numerous runs down the hill to big bend in the Blethems company)

But-don't even begin to give that dyno number (132hp) credibility. It is so typical of the bullshit #s coming off chassis dyno operators.

Sorry-maybe thats another subject, but as a practical matter I consider chassis dyno info to be useless in this context. For A/B/C comparisons they are useful, but not here. (IE: if you could put several cars on the same dyno on the same day, correcting for atmospheric conditions each pull-that info would be good data. Whether it would be good information would be questioned, but context is everything)

Point is, don't screw the pooch any further by running with this (132hp) information Steven has humbly (foolishly?) provided.