Spec Miata Community   
search | help | calendar | games | forum home

  next oldest topic   next newest topic
» Hello Spec Miata Community » SpecMiata.com » Spec Miata » How much does HP and TQ mean in regard to lap time (Page 2)

 - Email this page to someone! | Subscribe To Topic
Page 2 of 2 1  2 
 
Author Topic: How much does HP and TQ mean in regard to lap time
David Dewhurst
Veteran Member

Posts: 574
Status: Offline
Icon 1 posted  Profile for David Dewhurst     Edit/Delete Post  Report this post to a Moderator

quote:
Originally posted by Jim Venable:
Bob,

Very nice video quality. What system is it?

Jim
"Nice Guy Jim Racing"

Video is from Greg Gauper's H production car. For contact go to the production car site members list & pm Greg.

[Wink] [Wink] [Wink] rightie , shall I through a request ask if we can remove the direction light stalk? It consistently looks bad turning left through T5. [Wink]

--------------------
Have Fun [Wink]

David Dewhurst
CenDiv
Milwaukee Region
Spec Miata #14

Zauskycop Verified Driver
Member

Region: Chicago
Car #: 45
Year : 1991
Posts: 115
Status: Offline
Icon 1 posted  Profile for Zauskycop     Edit/Delete Post  Report this post to a Moderator

Rightie...I sorta like that nickname ;-)

--------------------
Tracy Ramsey
Team Blenderblaster

Bellwilliam Verified Driver
Member

Posts: 26
Status: Offline
Icon 1 posted  Profile for Bellwilliam     Edit/Delete Post  Report this post to a Moderator

quote:
Originally posted by Bellwilliam:
doesn't the plate just choke off top end ? whereas a pro motor has more power everywhere.

since you were running with plate off (where gain is on top end only). gain would be less than if you were running a junkyard vs. pro motor (gain everywhere from 2k rpm to redline).

so it would be a little more than 1.2 second you seen. my guess is 2 seconds if it were a junkyard vs. pro motor.

B Wilson Verified Driver Series Champ
Gold Member

Region: Oregon
Car #: 68
Year : 91
Posts: 2359
Status: Offline
Icon 1 posted  Profile for B Wilson   Author's Homepage     Edit/Delete Post  Report this post to a Moderator

Okay I'm okay with 1.2 seconds. The car I was testing (down 7hp) also had shifting problems. I started compensating for that issue by shifting slower.

What does that tell about having a working transmission??? Can a good tranny can yeild .8 seconds better lap times? I think so!

-bw

--------------------
Bruce Wilson
2010 Oregon Region Champ
2010 Monte Shelton Driver of the Year
2010 25 Hours of Thunderhill E3 and Under 2 liter Overall Champion
Oregon Region SM Class Advisor

Mark de Regt Verified Driver Made Donation to Website
Veteran Member

Region: NWR/Oregon; ICSCC
Car #: 70
Year : 1991
Posts: 1111
Status: Offline
Icon 1 posted  Profile for Mark de Regt   Author's Homepage     Edit/Delete Post  Report this post to a Moderator

quote:
Originally posted by B Wilson:
Okay I'm okay with 1.2 seconds. The car I was testing (down 7hp) also had shifting problems. I started compensating for that issue by shifting slower.

What does that tell about having a working transmission??? Can a good tranny can yeild .8 seconds better lap times? I think so!

-bw

Well, except that was on a 2 mile course, with the chicane.

I have difficulty thinking that ten rwhp, which is significantly more than the difference between the typical crate motor and the typical pro motor, will yield only 1.2 seconds over a four mile course, under race or qualifying conditions.

I could maybe believe that in lap times on an otherwise empty track, but with other cars on the track, the ability to stay in the draft, especially on a long course, would, I think, translate to more difference.

It was my car Bruce was driving. I know that in the test day a week before the race, my lap times were less than a second slow, little enough so that I could convince myself that the car was ok, and the slightly slower times (and much later shift point on the long straight) were due to my rust. But in qualifying and racing, I was more than 1.5 seconds slow, on a 2 mile track, and I couldn't hang with anyone, even if I was on their tail, with a better exit from the last corner; forget about passing anyone.

These data are no more scientific than Jim's data (and, indeed, I have no idea how much down on power the car was; I know that all was back to normal when I put a new motor/transmission in), but there they are.

Jamie Tucker Series Champ

ARRC 2010 Champ

Region: CFR
Car #: 97
Year : 1990/99
Posts: 788
Status: Offline
Icon 1 posted  Profile for Jamie Tucker     Edit/Delete Post  Report this post to a Moderator

quote:
Originally posted by tony senese:
IMHO a fast driver in a slow car will always go faster than a slow driver in a fast car.....

I would have to agree! I know when I got my first pro engine I just knew I was going to be running up front. Unfortunately my lap times did not change and I was still a mid-pack driver. The next race I had another driver qualify my car since I was not going to be there on time; he put it on the pole. When I started the race I went back to mid-pack so fast I had to turn on my reverse lights. I will make a guess that we are looking at .800 of a second; which of course is a lot if you are racing against other fast cars. I ran one of my 99s at PBIR a few weekends ago in ITS and was less than 1 second faster without the plate and that is a 10 HP and 7 TQ increase.

--------------------
2010 ARRC Champion
2010 CFR Champion
2010 instigator of the year
2010/2011 Andrew Von C Wingman

Drago Verified Driver Made Donation to Website Series Champ
MegaModerator

Region: mid south
Car #: 2
Year : 1999
Posts: 4275
Status: Offline
Icon 1 posted  Profile for Drago   Author's Homepage     Edit/Delete Post  Report this post to a Moderator

quote:
Originally posted by Mark de Regt:
[QUOTE]Originally posted by B Wilson:
[qb]
I have difficulty thinking that ten rwhp, which is significantly more than the difference between the typical crate motor and the typical pro motor, will yield only 1.2 seconds over a four mile course, under race or qualifying conditions.


Well my laps is up, so you can see for yourself... http://www.mylaps.com/results/showevent.jsp?id=540308

This was done to win a race, not to prove some type of a point, I drove 10/10 in both races, if anything, I had to drive harder in STU, SM race I was able to drive my pace from the pole.

Jim

--------------------
Jim Drago
East Street Auto Salvage
jdrago1@aol.com
2006-2007 Mid-West Division
07,09 June Sprints Champion

EAST STREET RACING

Mark McCallister Verified Driver Made Donation to Website
Just graduated from novice to rookie!!

Region: Central Florida
Car #: 40
Year : 1991
Posts: 393
Status: Offline
Icon 1 posted  Profile for Mark McCallister     Edit/Delete Post  Report this post to a Moderator

It might be the case that the lap time difference between a 110 hp car and a 120 hp car is not the same as the difference between a 120 hp car and a 130 hp car.

Sean Yepez Verified Driver
Team Keeblerspeed

Region: SF
Car #: 94
Year : 94
Posts: 671
Status: Offline
Icon 1 posted  Profile for Sean Yepez     Edit/Delete Post  Report this post to a Moderator

quote:
Originally posted by Mark McCallister:
It might be the case that the lap time difference between a 110 hp car and a 120 hp car is not the same as the difference between a 120 hp car and a 130 hp car.

Or 128 vs. 138. [Big Grin]

10 horsepower is huge on a Spec Miata.

--------------------
2008 San Francisco Region SMT Champion

Mark de Regt Verified Driver Made Donation to Website
Veteran Member

Region: NWR/Oregon; ICSCC
Car #: 70
Year : 1991
Posts: 1111
Status: Offline
Icon 1 posted  Profile for Mark de Regt   Author's Homepage     Edit/Delete Post  Report this post to a Moderator

quote:
Originally posted by Drago:
This was done to win a race, not to prove some type of a point, I drove 10/10 in both races, if anything, I had to drive harder in STU, SM race I was able to drive my pace from the pole.

I believe you. What I don't believe is that the data would be the same as the difference between having, say, 110rwhp and 120rwhp on an otherwise identical Spec Miata, driving in an otherwise identical SM field.

Your data involved changes in your car to accommodate the rules of two different classes, so that your car was highly competitive in both classes. So you had the benefit of drafting, etc. in both classes. And, as pointed out, it's probably not 110 vs. 120 we're talking about, but significantly higher numbers (and, hence, less significant as a percentage).

Not trying to knock the data; just offering some caution about how applicable the data are to a junkyard motor vs. pro motor analysis for Spec Miata.

Drago Verified Driver Made Donation to Website Series Champ
MegaModerator

Region: mid south
Car #: 2
Year : 1999
Posts: 4275
Status: Offline
Icon 1 posted  Profile for Drago   Author's Homepage     Edit/Delete Post  Report this post to a Moderator

I think you are missing my point... both laps were set with the car indentical conditions and trim, literally even same tires. The only difference was plate. Both laps were out by myself. There was no special prep done for STU except pulling the plate. I think the 1.2 seconds is a a very far assessment at that track with that car and me driving, could it be a few tenths either way, sure it could. Could the difference be more or less in a 1.6, a pro vs non pro motor and several other scenarios? Sure it could. Just thought it interesting and figured many others would as well. I truly expected 2-2.5 seconds and it just didn't happen.


Also, car on my dyno does make 127/128 hp, not 120. so we are probably talking 127 vs 137.

Also, my first inclination was that over 4 miles the HP would make the most difference. The opposite may in fact be true? We may need even more HP to propel the car significantly faster down the straights and that is all we are really talking about. It may very well be that you get the same gain or perhaps more at a track like Barber with more stopping and going and not hitting max velocity on the long straights? No idea here, just thoughts.

--------------------
Jim Drago
East Street Auto Salvage
jdrago1@aol.com
2006-2007 Mid-West Division
07,09 June Sprints Champion

EAST STREET RACING

wheel Verified Driver Made Donation to Website
Member

Region: kc
Car #: 20
Year : 92
Posts: 1801
Status: Offline
Icon 1 posted  Profile for wheel     Edit/Delete Post  Report this post to a Moderator

Jim,
I think you are correct, about longer tracks. As these things reach terminal velocity, the HP requirement goes up exponentially. So, much more HP and TQ would be required to gain the same increase in speed at 120 as at 70. I bet your lap times, at Hallett, would come down by a bigger percentage.
wheel

d mathias Verified Driver Made Donation to Website
Member

Region: OVR
Car #: 88
Year : 1991
Posts: 2401
Status: Offline
Icon 1 posted  Profile for d mathias     Edit/Delete Post  Report this post to a Moderator

Sooooooo, the point of all this would be... [Big Grin]

wheel Verified Driver Made Donation to Website
Member

Region: kc
Car #: 20
Year : 92
Posts: 1801
Status: Offline
Icon 1 posted  Profile for wheel     Edit/Delete Post  Report this post to a Moderator

That depends on to which "this" you are referring.

Drago Verified Driver Made Donation to Website Series Champ
MegaModerator

Region: mid south
Car #: 2
Year : 1999
Posts: 4275
Status: Offline
Icon 1 posted  Profile for Drago   Author's Homepage     Edit/Delete Post  Report this post to a Moderator

quote:
Originally posted by d mathias:
Sooooooo, the point of all this would be... [Big Grin]

To see what size restrictor plate to put on the 1.6 of course! [Eek!]

--------------------
Jim Drago
East Street Auto Salvage
jdrago1@aol.com
2006-2007 Mid-West Division
07,09 June Sprints Champion

EAST STREET RACING

pat slattery Verified Driver Made Donation to Website
Veteran Member

Region: cincy
Car #: 79
Year : 92
Posts: 1495
Status: Offline
Icon 1 posted  Profile for pat slattery     Edit/Delete Post  Report this post to a Moderator

quote:
Originally posted by Drago:
quote:
Originally posted by d mathias:
Sooooooo, the point of all this would be... [Big Grin]

To see what size restrictor plate to put on the 1.6 of course! [Eek!]
[shame] [Mad]

Pat [Big Grin]

--------------------
keeping the faith for the 1.6

Arrow Karts

d mathias Verified Driver Made Donation to Website
Member

Region: OVR
Car #: 88
Year : 1991
Posts: 2401
Status: Offline
Icon 1 posted  Profile for d mathias     Edit/Delete Post  Report this post to a Moderator

quote:
That depends on to which "this" you are referring.
Is that you President Clinton?

davew Verified Driver Made Donation to Website
Veteran Member

Region: chicago
Car #: 72 and ?
Year : 90 and 90
Posts: 1051
Status: Offline
Icon 1 posted  Profile for davew   Author's Homepage     Edit/Delete Post  Report this post to a Moderator

Quick math, GT1 car has 800 horsepower. So it has 6 times the hp of an SM. But it does not go 6 times faster.

There are a lot of things called physics that come into play. GT1 at Road America 175mph lap time 2:08, SM 125mph 2:45

So if 600% increase in the horsepower gets you 40% increase in speed, I would expect a 10% increase to only gain a couple mph.

One of my cars did the exact same thing as Drago, ran SM and STU with the only change to the car being the removal of the restrictor plate. About 1 second per lap average difference. So Jims data is confirmed by my data from a 99 with stock, untouched 100,000 mile motor.114hp

Using Sundays Road America SM race best laps, if the 10th place driver had 10 more hp (resulting in 1.2 seconds faster) he would move from 10th to 7th. And that is on a horsepower track!!!! On a 2 mile twisty track I bet the difference is 0.2-.03 sec

Will 10 hp move you up in the finishing position? About 3 places!!!!!!!!

These cars are sooooo close and so underpowered that the driver is WAY more important than the engine.

Dave

--------------------
Advanced Autosports, The Midwests leader in Spec Miata Service, Parts and Rentals
608-313-1230
Authorised Spec Miata service center
www.advanced-autosports.com

Drago Verified Driver Made Donation to Website Series Champ
MegaModerator

Region: mid south
Car #: 2
Year : 1999
Posts: 4275
Status: Offline
Icon 1 posted  Profile for Drago   Author's Homepage     Edit/Delete Post  Report this post to a Moderator

quote:
Originally posted by davew:
Quick math, GT1 car has 800 horsepower. So it has 6 times the hp of an SM. But it does not go 6 times faster.


Well we all know that is because SM drivers are twice as fast as your average GT1 driver! [Big Grin]

--------------------
Jim Drago
East Street Auto Salvage
jdrago1@aol.com
2006-2007 Mid-West Division
07,09 June Sprints Champion

EAST STREET RACING

Brandon F. Verified Driver
Member

Region: NNJR
Car #: 48
Year : 1996
Posts: 191
Status: Offline
Icon 1 posted  Profile for Brandon F.     Edit/Delete Post  Report this post to a Moderator

quote:
Originally posted by Drago:
quote:
Originally posted by d mathias:
Sooooooo, the point of all this would be... [Big Grin]

To see what size restrictor plate to put on the 1.6 of course! [Eek!]
You just made me LOL - and everyone in my office just looked at me.
[laughing]

ToddW Verified Driver Made Donation to Website
Objects in review mirror are losing

Region: SFR
Car #: 67
Year : 92
Posts: 59
Status: Offline
Icon 1 posted  Profile for ToddW     Edit/Delete Post  Report this post to a Moderator

More than lap time improvements, having optimum HP and Torque helps during the race to hold or gain positions. If you have to work yourself and the car extra hard in the corners/braking just to lose it on corner exit and the straights, it can be a long (but eventful) race as you deal with challenges from behind...while the cars ahead drive away.

David Dewhurst
Veteran Member

Posts: 574
Status: Offline
Icon 1 posted  Profile for David Dewhurst     Edit/Delete Post  Report this post to a Moderator

[/qb][/QUOTE]To see what size restrictor plate to put on the 1.6 of course! [Eek!] [/QB][/QUOTE]

Here, fishy fishy fish............. [Razz]

--------------------
Have Fun [Wink]

David Dewhurst
CenDiv
Milwaukee Region
Spec Miata #14

oem steve
Member

Region: South East
Car #: #92
Year : 91
Posts: 189
Status: Offline
Icon 1 posted  Profile for oem steve     Edit/Delete Post  Report this post to a Moderator

I think a question on Drago's test would be how much of a differance on the dyno does his motor make with and without the plate and where does the differance show up at (ie) above 6000. If the plate only drops power above say 6000 then at tracks that you have to pull lower RPM out of the corner it shouldn't make much of a differance. I would like to see acomparison with say a crate motor and a pro built motor. IMO

--------------------
email: standrewsexpress@bellsouth.net
visit us at http://www.standrewsexpress.com

Under powered and under driven

Bellwilliam Verified Driver
Member

Posts: 26
Status: Offline
Icon 1 posted  Profile for Bellwilliam     Edit/Delete Post  Report this post to a Moderator

nobody answered my question.

plate vs. no-plate is NOT the same as pro vs. none-pro motor.

no-plate makes 10 more whp, but high end only, basically the same hp curve as plate, except 10 more whp at 6,000rpm +.

whereas, pro motor makes more power everywhere (vs. none-pro motor).

is this correct ?

Drago Verified Driver Made Donation to Website Series Champ
MegaModerator

Region: mid south
Car #: 2
Year : 1999
Posts: 4275
Status: Offline
Icon 1 posted  Profile for Drago   Author's Homepage     Edit/Delete Post  Report this post to a Moderator

You are correct, but we never dip below 5000 rpm and only hit 7000? The plate really shows up at 5500-6000 and above. I think you are splitting hairs maybe, but agree with the principle.

--------------------
Jim Drago
East Street Auto Salvage
jdrago1@aol.com
2006-2007 Mid-West Division
07,09 June Sprints Champion

EAST STREET RACING

Jay Lutz
Member

Region: Indy
Car #: 33
Year : 1994
Posts: 422
Status: Offline
Icon 1 posted  Profile for Jay Lutz     Edit/Delete Post  Report this post to a Moderator

The real question should be: how much more total work does the no plate engine do (compared to the plate engine) over the RPM range in question. Citing a single torque or HP number ignores the fact that some configurations make a lot more torque on the way up to peak RPM.....and this is important.

Remember, HP is just a calculation and is not measurable....you measure torque on the dyno only. HP=(torque*RPM)/5252 So by definition, all engines make equal torque at 5252 RPM....just plug in the numbers to prove it to yourself.

Back in my HP Sprite days when we were doing a lot of dyno testing at Comptune in Medina, OH we actually did a spreadsheet calculation on total work for all data points between 6000 and 8500 rpm. We always went with the configuration where this was maximized....and frequently the peak HP numbers were a little down compared to other configurations.

--------------------
"In our sport if you go out of bounds you're most likely not coming back" Michael Waltrip

 
Page 2 of 2 1  2 
 

   Close Topic   Feature Topic   Move Topic   Delete Topic next oldest topic   next newest topic
 - Printer-friendly view of this topic | Subscribe To Topic
Hop To: