3Deuces

I realize I might be in enemy territory here but I was wondering if someone could refresh my memory please. I recall that the Callaway Twin Turbo came out a few years before the ZR-1 as a regular production option but never received anywhere near the notoriety of the ZR-1. Does anyone have the stock specs of the two of them side by side? Which had more HP?, Torque? Just wondering.

Thanks


[Modified by 3Deuces, 11:40 PM 8/4/2001]

90 Corvette ZR-1

If I remember right the TT made something like 500 FTlbs. But I know from talking to a few of my friends that have the TT, that the like the blow connecting rods

90Callaway

Here you go... better get a magnifying glass to read it though!! I believe these are both 1990 models. Stock to stock the Callaway is marginally quicker. But what fun would it be to leave them stock! :D



This is a good article from Corvette Magazine comparing the two.
http://www.corvettemagazine.com/2000...callawayp1.asp

Enjoy! :chevy

Canzr1

No problem, both of these machines are world class, I can tell you without reservation that my next Corvette will be a '90 or '91 TT. I also believe the TT may edge the ZR in most categories, its really apples to oranges as we are talking DOHC V8 to a stuffed pushrod motor. I adore the TT, Here are some facts I have on the 1989.....
382 hp @ 4259 and a whopping 563 lbs ft @ 2500.
0-60 4.46
0-100 10.52
12.88 @ 111.58
Top speed 192 mph

These stats are with the Aerobody installed. AWESOME!!! :chevy

OldZR-1Guy

I know I'm a broken record on this, but the manufacturers numbers on the '89 TT were highly optimistic. AeroBody or not, a car with 382 HP, a power peak at 4200 rpm and a 3.45 rear end is not going 192 mph. I had an '89 TT (non Aero) and 165 mph was about it. Just based on revs, and despite the weight disparity, the ZR-1 would walk the TT on top end. 0-60 and the quarter mile would be a toss up depending on the driver. As a quick comparison, note the Ferrari 360 Modena: just under 400 HP, a little over 3000 pounds, and a redline around 8 grand. The top speed of the Ferrari is a bit over 180, and this is with excellent aerodynamics. Just a little dose of reality. ;)

SurfnSun

So you ran a Callaway TT to a max speed of 165mph and thats all it had??? My 85 will run close to 150(ive seen 144mph and it was still pulling) and its down 150hp and 200lb/tq. :bs




[Modified by SurfnSun, 10:53 PM 8/6/2001]

OldZR-1Guy

Yup. Foot to the floor. 165. As I mentioned before it's a question of the power peak of the engine and the gearing. When you hit 4200 rpm the car was just done. You could keep your foot in it but the car wouldn't gain any speed. Could my car have been down on power? Not likely. But just for the sake of argument let's say it was down 25 HP for some reason. What would that get me? Once you get past 150 each mph takes a lot more horsepower. I suppose a different car might go 175, but that's a long way from 192.

SurfnSun

Look at the graphs above....

At 5000rpm the Callaway is still making 350lb/ft of torque....thats only 25lbs less that the ZR1s total. Don't think thats enough power to still pick up speed? What gear were you running? Something's amiss.....A friend of mine in an LT4 saw 163 I think

90Callaway

OldZR-1Guy - I must respectfully disagree that your TT was in peak operating condition. I've seen you post before where it didn't have any power above 4200rpms. Stock TT's are good for at least 5000rpms before they fall off. Mine with intake work is still pulling like a freight train at 5500rpms + and would probably keep right on pulling. I won't take it past that even though it's got a bullet proof bottom end (not stock). I have not done any top speed runs.

There are two forum members, who don't seem to post here much any more, that have TT's and have run them up to at least 200mph. That's with stock bottom ends. They would be UltraSlow and 8388.

Sorry your car didn't live up to it's potential...

RatRacer

I agree, in speaking with Ultra Slow he indicated that TT's often don't run up to snuff because of various issues. In fact, I was going to buy the car he owns. When I test drove it I was disapointed with it's performance. It turned out to be a bad turbo or something. It was a long time ago so I don't remember exactly what but he fixed it and now it's 500+ rwhp.

Cameron

USAZR1

I've been following this thread for awhile and am curious about a few things,90 Callaway. What trans are these TT's running? ZF or auto? What kind of gearing are these "supposedly" 200mph cars running? Running the numbers,a TT with 3.45 gear would not get anywhere near 200 mph(actually 162mph) at 5,500 rpm in 5th (ZF trans) so 6th gear would have to be used. It's hard to believe that a TT or almost anything else could pull 5,500 rpm(244mph) in 6th gear. According to my gearing charts(3.45 gear, 315/35/17 tires, .75 5th gear or .50 6th gear), a TT would have to be able to pull 4,600rpm to see 204mph in 6th gear. Not impossible but a tall order.
Your comments are welcome.
Clint

SurfnSun

Torque man, Torque....look at the torque mountain..err curve :D If shifting to sixth put put the car at around 3k rpm I think itd be safe to say it would still pull. If 4600rpm=204 then to say that the car would pull to 3800-4200 would leave you in that 190 range, right?

In the Z06 Forum OldDude posted that "192 in fifth would be a strech"....of course it would gear ratio/rpm tell us that wouldn't happen in a B2k car!! Callaways used 6th gear to top out. Why?? you ask.....it all goes back to torque. Hp is a function of it. Do you think that 18wheelers have high hp engines? I'll give you hint, they redline at about 3k rpm.

Heres a thought provoking question......
How fast would the TT car go if it had enough gears to stay around its torque peak?


[Modified by SurfnSun, 6:42 PM 8/7/2001]

SurfnSun

Was that the 88 or 89 that you drove?

90Callaway

Well Clint I wasn't there so I don't know what gear they were in. I do know that these guys are not BS'ers so if they say they went 200mph, I believe it. I'm not about to go out and try it tonight to prove a point.

I'm almost positive that we're talking about ZF6 equipped cars with most likely 3.45:1 rear end gears. It would not surprise me if they were able to pull 4600rpms in 6th. I think you've proven that it's the only way it could be done. SurfnSun pretty much summed up the reason... incredible torque.

USAZR1

I wasn't necessarily doubting Matt's word but his TT has been heavily massaged,hasn't it? If anything can pull the tall 6th gear, a modified TT car could. But,it would probably take over 600rwtq to do it and even that's not for certain. Sure would be fun to try,though.
Clint

OldZR-1Guy

To '90 Callaway: Well how would you know what kind of shape the car was in? The answer is it was in perfect shape. I always kept it in mint shape inside and out. I'm not disparaging the car, I really loved owning it and driving it. The point of my postings has been to debunk what are inflated claims as to the top end speed of a stock Callaway TwinTurbo from '88-89. I simply state that the torque peak of the car was 4200 rpm and there was not much use in pushing the car past it. It would run out of breath and you were better off changing gears. Re-read Clint's post concerning stock gearing and top end. His calculations are right in line with my experience of several top end runs. You say your car still pulls to 5500 rpm. But you also say that your car has a revised intake and bottom end. And from you sig I gather it's a '90. I didn't say anything about what that MY will do because I have no idea. I did own an untouched Bloomington Gold certified 1989 Callaway TwinTurbo and I can speak with some authority about the characteristics of that car. I noticed that you have not done any top end runs. I urge you to make an earnest run at 175 mph. I would be interested to hear if the car could get there and in what gear. You will need several miles of road. There's no way in the world that my car would have pulled top end in 6th. It's an overdrive gear and the engine did not make enough power to get that done. 190 mph is a very tall mountain and I have a hard time believing that a stock '88-89 car could do it. Hell, I'm driving a '92 ZR-1 with 520 HP and I'm not positive that car could top 190 even if I had stock rear gears in it. I think it'll do 180 with the 4.09s but I haven't found the right road to try it. The point here is that this car would stomp my old TT like it was a Ford Taurus and I'm still not convinced it would do much better than 190 with 3.45s. As for someone topping 200 with a stock '88-89? Not possible. Reeves Callaway told me that the AeroBody needed 512 HP to top 200. Meaning an '89 with the AeroBody is 130 HP short. The AeroBody was not offered in '88.


[Modified by OldZR-1Guy, 11:31 PM 8/7/2001]


[Modified by OldZR-1Guy, 11:33 PM 8/7/2001]

JoBy

Hello!

Personally I have never had the chanse to drive (or ride) in a ZR1 or TT.
I have an 84 Cross-Fire that I put a Vortech supercharger on with very good results.

Anyway ...

I took a street dyno run I made.



I was playing around with the dyno numbers in Excel.

Instead of plotting the hp and tq against rpm I used vehicle speed as x-axis.

Speed is easily calulated using tire size, rear end ratio, gear ratio in tranny and engine rpm. I made one table for each gear and plotted them in the same chart. I also multiplied the tq value with total gear ratio to get rear wheel tq for that gear. I divided the rwtq value with the weght of the car to get a SOTP number.

I have 3.45 in the rear end and a th700r4.


I used blue for hp (scale to the right)
pink is SOTP.



The speed (0-300) is km/h in the graph.

For maximum acceleration you should use the gear that gives you the highest hp / rwtq value. The optimum shift points are where the curves intersect. Both hp and tourqe intersect at the same speeds.



[Modified by JoBy, 1:19 PM 8/8/2001]

SurfnSun

Simply b/c a car is mint looking inside and out doesn't mean the turbo system is in perfect working order. I test drove an 87 Callaway with 19000 miles, the car was mint. BUT the car was having boost problems of some sort, it wasn't much quicker than my 85.

Did you mean the hp peak was 4200? The torque peak of the Callaway was around 2500-2800rpm.

Topping 200 stock?? No one ever said that, Stock and stock bottom-end are totally different. You said the car won't go 190. We said it will or will get very close. Ultra Slow has 2 Callaways an 88 and 89, the 88 has 520hp and the 89 600hp I think. Yes his cars do over 200. Aerobody is only good for 5 to maybe 7mph, the purpose was to cancel body lift and stabilize at high speed.

Maybe I'll send a link to Ultra Slow and see if we can get his input.


[Modified by SurfnSun, 9:30 AM 8/8/2001]

scorp508

What are the 5/6 gears in the ZF6 again? .75 and .50? I forget. I have no doubts that a properly tuned TT could pull 6th gear. Heck, my '87 can/will hit top speed (154, I've seen 151 so far) in both of my last gears (4+3 tranny) of .90 and .68. Then again my Dana 44 is a 3.07 gearset.

And she's only got 211 rwhp and 315 rw ft/lbs!

RatRacer

Both Matt(ultraslow) and 8388 TT's are running essentially stock engines with a lot of boost. Matt's TT that I drove was a '89 with an automatic tranny. It has around of 600 ft/lbs of torque if memory serves me. To give you an idea how fast these particular TT's are 8388 ran 4cefed's '90 ZR-1 with his TT from a rolling start. The TT pulled the ZR-1 3-4 carlengths by the time 4cefed grabbed the next gear.

BTW, 8388 has a 4+3 tranny in his TT.





[Modified by Cam Potter, 10:30 AM 8/8/2001]