IcemanG17

Doc
Well said.......

I believe the strength of the 928 platform on a racetrack is its ability to put power down IN the corner....earlier than most other "Race cars"....this with its high TORQUE engine means getting a nice jump off that corner....

MK gained 1.5-2 seconds from 55whp...but in reality he went from 300 to 400 ftlbs..... Flame suit on.....as MK will be typing like crazy soon

I'll be "testing" in the real world again, this Friday.....I look at it as non stop development program.... Hopefully there will be more ZR1's out there

James Bailey

Give them HELL !!! you are having too much fun !

mark kibort

No, this is very very wrong brian and you should know this!
again, the GT3 vs viper is the best example i can give of the "term" comparison. if both have 500rwhp, and both have 500rwhp at any point of the race track, even off the turn, they will accelerate the same. Greg is still living in the past when there were 911s vs mustangs with V8s and they both had distinct advantages. Now adays, the vets are as light as the 911s.
point is, my 55hp was a REAL 55hp, not like the S2000 guys that gain 150hp peak hp and really average is only about 50. Remember Blackey in the S2000 with the supercharger and 420rwhp???? i studied his HP curves before the race and found out i actually had an advantage average HP was near the same, even though i had 372rwhp vs his 420rwhp.

and as a side corrective note. i went from 330rwt to 420rwt and then detuned to 400rwhp. for 70ftlbs and 55hp. Point is there, the 55hp was REAL 55hp gained, and thats a big deal.. its not due to torque, or the shape of the torque curve as actually it is falling after 4500rpm quite hard, but thats what you get with a FLAT hp curve. which many 928s have . sorry Greg, real world racing use of HP and torque, shown in my example and descriptions. those that cant get off the turns in a GT3 (*and none of them have not been trained in using the proper gear or reading HP curves. )

so, two things with greg. He must not be able to remembrer much , or he just doesnt understand the basica laws of physics, both in practice and in reality.

watch much speed GT or ALMS?? i just think its a crackup when the anoucers used to say, "watch the vet come off this turn with the V8 grunt vs the porsche" and then the porsche actually closes off the turn, and down the straight. notice why Greg Kramer doesnt say that anymore. Yes, he read a heated debate one time, joked about it on TV once and then stopped doing it. you are living in the product of marketing world if you dont understand that its power that is the KEY. its the rate of change of kinetic energy which, by definition IS acceleration!!

GregBBRD

I guess, in the end, I really don't know very much, compared to others.

I just try and repeat the lessons that I've learned, in real life. And having built and raced cars virtually my entire life, I have learned a couple of lessons.

With everything else being equal, on an individual car, I'll trade top end horspower, for mid range torque, every single time.

Let's all try to remember:

Apparently, it takes "more hammer" than 900 hp to power a 928 faster than 205mph. Someone said that trading all that torque for top end horsepower wasn't going to work....

Who was that?

mark kibort

Greg, i know you well enough to jab you now and again. yes, what we are saying is both right , but what im talking about is the torque alone, as a value. it means very little. (unless RPM is associated to it) so, when you beef up the torque, as porsche did, (RPM DIDNT CHANGE MUCH) you broaden the HP curve. again, we both are saying the same thing in effect.

BUT NO!!! top end up for mid range does just the opposite, if done in proportion , why???? becuase you spend more time in the higher RPM range becuase acceleration is harder there to come by! acceleration does down with speed, proportionately, even if you had a flat HP curve with a infintely variable gearbox.

so, this is why the euro 290rwhp vs the us 240hp with actually less peak torque than the US, was MUCH faster. because its HP-seconds! area under the HP curve, period!! try it, it will prove right every time with every one of your experiences.!!

Mk

IcemanG17

Wise men on this page....................

I LOVE IT....when "we" (which means my mechanic) make a change, I go out on track and the car feels BETTER......then I review the data & the car went faster....

Right now its small alignment differences.... For example, I was debating going lower ride height but my setup of short S4 upper arm with early lower arm makes for LOTS of camber going low (too much, MK was right)...and my tire temps are great across the tread right now...so why mess with it....125mm-155mm sounds high....but the car is handling great....

When the car was really low (95mm) my front camber was between 3.3-3.5' and tire temps were hotter on the inside by 40F & they were cording on the inside 1st....

Its a never ending work in progress!!!

James Bailey

Kibort you live in a delusional world you "race" with a bunch of ******* and sometimes win. The chest pounding gets real old, real fast. Which is about the only time Kibort and fast belong in the same sentence. You have clearly avoided racing with Anderson or Fan and with good reason your nearly unlimited ego can not handle the reality check. But, but, but, adjusting for weight tires temp atmospheric pressure the phase of the moon ............ then have the audacity to post as an "expert" sorry but I am not buying it. Comparing your experience at Laguna in a LOCAL club race with Greg at Daytona IMSA event, not even in the same league literally.

IcemanG17

Umm.....I disagree with this....my current 243whp USA-ish-I dunno what engine it is FASTER than the 290whp 5.0L hybrids....

I will agree that the track is faster now, but 2:03.7 for Scott on much wider tires with 50whp & 40 torque more....I think his is slightly lighter too since I'm at 2719

How is this possible? It must be the GEARING

James Bailey

Yes track time can be expensive but it is also PRICELESS !!! will be at Cal speedway Fontana this weekend doing the infield course....too much fun !!

James Bailey

Yes and my lap times have been better the a GT3....so what ?? it is not the car. Plus many of the cars at a "track day" are NOT RACING !!! Just having fun....The guy with the GT2 RS which I drove had no interest in putting his $300,000 car in the wall. My $2,000 928 .....no problem !! Hang it out ....

inactiveuser1

ZR1 torque is impressive at 604 lb.-ft. of torque at 3800 rpm
Its has good torque the stroke is longer than 928 as ZR1 is 3.62 inches.
High torque 928 engine?At 3.11" stroke its more on par with old Chevy or any Ford 302 as they were short stroke 3inch.
You must be thinking of Gregs stroker motors,those are way longer stroke and those would have torque.
Longer stroke motors are have more torque,thats why people build strokers for the pulling power.


Street cars drivers are just out there cruising at speeds they feel save at to have a good time.
On cruise control ZR1's are probably pulling 400ft lbs of torque part throttle lol Titanium valves and rods from factory is a nice setup on the Chevy motor.
At the drag strip they have alot less chance hitting the wall even thou it does happen.
Thats when the street cars are driven more all out.

http://www.chevrolet.com/corvette-zr...ml#Performance
638 horsepower at 6500 rpm and 604 lb.-ft. of torque at 3800 rpm.


For new car performance ZR1 is alot less than Euro or Italian cars.People are paying more for those since our dollar is so weak.

mark kibort

its so funny, everyone wants to re-invent the wheel! with all the testing ive done, (and most of my starting points came from anderson who raced at a high level before I did) why not use what WORKs first>> anyone that doesnt start at 1.7 degrees front and 2degrees rear camber, 110/140mm ride height, 0 toe, is starting out re-inventing the wheel! even if i doesnt work, it can work, its proven, but NOTHING so far has been posted that works better than above, so why not start there and adjust. there is a reason i can build a 928 racer, adjust it at home and have it run a race WITHOUT even a test day and have it run the exact same times as its predicesor. its called "set up specs".

we are lucky to be able to exchange information here, but some folks just want to figure it out on their own. they are the ones with corded tires, loose/pushy cars, slow laps, and all sorts of other issues!

I know you were just anxious to get out on the track and still are,but some things will help you get faster much quicker, because you can start from a proven starting point

mark kibort

James, you havent clearly, been paying attention. i beat anderson all things being equal, except for his 200hp extra that he wasnt able to use during a PRO GTGP race .



also posted better times in the lemons racer at sears and thunderhill. you are delusional if you discredit 15 years of racing and bonified lap times with a known quantity. You know marks time in pro racing at laguna , sears and other world class tracks. you know what my car is. Mark A ran a 140.1 at the 2000 WCGT race, and i run 1:36-7 on similar tires and 50 less hp?? You are too impressed with lap time. there are so many bozos that get their lap times down. you see it at EVERY Grand Am , WC, races. the difference between a good pro and the decent club guy is the decision making you make on the track. this includes knowing their equipment. I'm pretty sure, Mark and I would turn similar times in my car on a given day. we ran almost identical times in the Lemons car But i can say with certainty, i wouldnt be able to beat his time in his car. Mark is real good at driving a fast car real fast. It would take me some time to get up to speed in his car, i would imagine.


Gregs IMSA experince doesnt make him a physics professor. Im just quoting basic laws here. you cant get better than a flat HP curve for a racer. the closest thing is a close ratio gear box or a wide HP curve for a given HP level. more hp in any area of a HP curve, is better, which is done by making more torque in those areas. dont confuse the two.

Now, put the ego down and listen up. what i tout is pure physics. it is the reason that one car is faster than another. (in a straight line or off a curve) if you understand it, you can use it to make your car go faster, if you dont, you can jump on marketing band wagons and stay in the dark. its all about HP and the HP curve, but more accurately, HP -seconds! HP includes torque, its a bonus factor because it contains so much. use toruqe if you want, but you better have a set of gear ratios and tire diameters handy to really understand what you got

again, acceleration = Power/(mass x velocity)

any car , coming of a curve with the same HP as another, regardless of torque values, will accelerate the same. this is a fact.

mark kibort

you are so funny. thats why they call slicks "ego tires". put the DOTs back on, specifically RA1s that were my throwaways and try and post a 2:02.

he only has 290rwhp, and torque i think is in the 280 range. i think you are probably in the 260rwt range, but thats a guess.

tires my boy. and his weight is the same. no set up on his at all for many many years. the biggest difference is driver and tires, for which you clearly have more right now by a long shot vs scot.

mark kibort

you are finally speaking some logic here!