just a random question who would win??? a grand national or a turba trans am in the 1/4??? i'm new to the boards and was just wondering

 

TTA would beat a grand national. There's one here in Tucson with slicks that went a 12.9.

 

TTA is approx. .4-.6 seconds quicker in the quarter on average.

 

yeap, basically the same engine, but the trans am weighs less and is more aerodynamic.

 

What about the TTA vs. GNX?!? Both cars -- :hail:

 

hmm the TTA would beat a GN, but TTA vs. GNX would be a heck of a race.

 

The big problem is that a lot of these cars are far removed from what they were stock.

I believe the TTA would win if both were stock, but on the street it's impossible to call if you don't know what each has under the hood.

 

the TTA would win hands down, it's more aeordynamic, less weight, and has a better engine in a way. It has a more efficient intercooler, better flowing heads out of the box and a higher ratio rocker arm.

I THINK it was Motor Tend that did a GNX vs. TTA battle back in the day. The GNX took the first 2 races but the TTA spanked the GNX in the 3rd race after the driver learned how to launch the TTA

 

HMM I m noticing that in every post by MDFormula350 on this board, all he does is recap what everyone else says! Um, ok...quit post whoring MDFormula350!!

 

Lol, you just noticed that?

Just picking on ya man

 

Yeah, just noticing for the past 7 months!

 

Well, I guess I'll just second what I've read above. But I sure want to get that GN in my neighboorhood to line up with me. I want to see that thing move. ^_^ I know i"ll lose badly though.

 

one more question, whats the difference between a GN and a GNX???

 

maybe I should try that

 

Cutting and pasting from last week....Different Intercooler (more fins/inch I think), different turbo (ceramic materials for faster spool), different chip, wheels, different rear suspension, reworked valve body, and some other stuff.

 

sounds like a significant difference, whats the difference in the 1/4?

 

13.1-13.3 compared to 13.8-14.2

 

I also believed the GNX motor had some help from Lotus in its design,or atleast some of its tweaks to differ it from the standard GN.G0D I cant wait to get a GN.soooo sweet :hail:

 

The engine's the same. At one point in time I think they'd thought about porting the heads but found that it wasn't needed to get the power they wanted. They also thought about using a TH-400 instead of the 200.

 

heres the differences between a GN and a GNX if you wanna know.a little more knowledge never hurt!!
-245/50/16 front & 255/50/16 rear tires mounted on 16x8black "honeycomb" wheels
-fender flares on each wheel well
-functional air louvers on the front cowls
-analog instrument cluster with Stewart-Warner gauges
-auxiliary transmission cooler mounted behind the front grille
-"improved" Garrett turbo with ceramic impellers and a custom GNX cover
-"improved" intercooler with serial number
-GNX emblems
-serialized plaque on dashboard
-ladder torque bar and panhard rod for better traction
-GNX graphic differential cover
-"improved" hydraulics in the transmission for firmer shifts
-dual exhaust from cat-back with separate mufflers for each pipe
....this car is the ultimate in my eyes.i mean c'mon,it even has a damn ladder bar stock! :hail: GNX

 

I think you're thinking of the LT5 in the ZR1 vettes

 

lol yeah i knew that too,but i coulda sworn that some other company had a part in the GNX.could be wrong though
oh well I STILL WANT ONE!!!:lala:

 

The GNX also had aluminum rear brake drums I believe.

 

Aerodynamics don't really play a role in 1/4 mile racing unless you are really moving.
A buddy of mine has a Regal T-type with some mods on the car.
Ran a 10.40 at 138mph spinning through the 8th mile. The t-type is pretty much the same as a GN.

 

TTA wins.

Besides the weight advantage, I used to have a dyno comparison of rear wheel hp/tq on TTA vs GNX. Believe IIRC the TTA had about 20 more hp and about 25-30 more torque...at the rear wheels. low 13s vs high 13s/low 14s like someone mentioned above.

You can buy the TTAs for reasonable prices. Good luck on the GNX.

 

some guys have dyno'ed their bone stock TTA's and have got up to 301RWHP, not bad for "outdated technology" as some LS1 guys say

 

back when my dad was alive in 2002 he picked up a t-type for 1500 dollars. none of my friends knew what it was but they were like man why did your dad buy that. after doing some tuning to the turbo and spending about 1000 on aftermarket parts i took it out. one of friends had a gst with some mods and was like" you wanna see what a real car can do??" well we took off and when the t-type hooked it was bye bye gst. that thing was crazy fast. and quite too. best of both worlds/

 

138MPH isn't really moving? Aerodynamics play a role after second gear, IMHO.

I've raced both a GN and a TTA on the street in Tucson. My torque gave me a car on the GN out of the hole but he was catching up hard at 100 mph. The TTA just... left.

 

Its like chosing between which of your kids do you love the most.... only if i had kids would i understand... i say TTA cause its a thirdgen..

 

Well, we were talking about stock cars which run about 105 in the quarter.

 

Ahhh, okie.


(Stock cars are boring IMHO as well. )

 

ASC MClaren played a part in the development/tweaks of the GNX. no, aerodynamics dont mean too much on cars under 200mph, weight on the other hand is very important. i concede the tta has many advantages stock for stock over a gn but how many are stock anymore?

 

A 1989 TTA has a coefficient of drag of around .31. The total frontal area is around 24 square feet. So using this data we can figure out how much force is put on the front of the car at speed, and how much horsepower is being used to overcome that force. (Assuming sea level.)
<PRE>
Speed F (lb/ft2) HP
50 51.46 6.86
80 131.74 28.10
100 205.84 54.88
150 463.150 185.25
</PRE>
Even with drivetrain losses and counting for rolling resistance, a TTA could make 150 MPH after awhile.

A vehicle with close to the same horsepower (245) but totally different aerodynamics (.45 CD, 25.9 ft2) is the 1993 Jeep Grand Cherokee V8. Let's see what horsepower is required to push this brick down the road.
<PRE>
Speed F (lb/ft2) HP
50 78.09 10.41
80 199.92 42.64
100 312.38 83.29
150 702.86 281.134
</PRE>
This brick will never see 150 MPH in it's lifetime. Weight has no factor in these calculations, and if you added the 5 HP to the Jeep, it's still severely lacking.

Now in regards to my original argument that aerodynamics play a role in slower speeds in the 1/4 mile. Look at the numbers in the charts below 100. A TTA is using a full fifth of it's horsepower within the 1/4 mile, just to overcome the air. On a smaller, less aerodynamic car, there's a large percentage of the engine's power used to push the air out of the way. My 1961 VW (.49 CD, 19.37 ft2) runs a 27.2 @ 56 MPH in the 1/4 mile stock. At the end of the 1/4 it's using approx 10 horsepower to push the air out of the way... a full quarter of the engine's power. If it had the same drag coefficient as the TTA, it'd be using 5 horsepower.

Judging from screwing around with the math... aerodynamics become a serious factor at around 75 MPH. At 138 MPH as stated above, a TTA would be using around 130 horsepower just for air. So I'd say it's a factor in the 1/4 mile.

And if anyone wants to use this as an essay in school.... tell me what grade ya get. I just saved you over an hour of math.

Many thanks to my coworker Jennifer Rehwinkle for helping me with my bad math.

 

Synapsis: where did you find all those numbers? I'd love to give that paper a good read.

 

The hard data about the coefficient of drag and frontal area was found here: http://www.teknett.com/pwp/drmayf/tbls.htm

Most of the concepts were on a website hosted by nasa.gov, but I don't have the link because it was given to me by Jennifer, along with other information from her college texts. She works on the Solar Car race team for the University of Arizona and a major factor in the design of the car is drag because of the low horsepower... and she just happened to have her texts with her that day. I made an Excel document where you enter the frontal area and Cd and it calculates the horsepower required for that car to do certain speeds in increments of 10, but that document is at work, I can attach it Monday if you'd like.

 

I would very much like that.

thanks


Wow...talk about a brick in the wind. My 91 mustang GT vert was a coefficient of .4! That, is painfull.

 

I know its off topic, but 98+ firebirds are the most aerodynamic american production car, and they get 30 mpg....

Just something to think about.

 

I always thought the 91-92 birds were the most aerodynamic?