Tta Vs Gn

[Cleaner13]

I was just wondering what the difference was between the TTA and GN

I met a guy last night with a TTA and he has practically nothing done
exhaust
chip
injectors
walbro fuel pump
and he ran a 12.30

that got me really jealous so I was wondering whats the huge difference between them and the GN

also does anyone know the flow differences between the TTA heads and GN heads?

thanks

Carl

 

[UNGN]

I didn't even have injectors and ran 12.20's in my TR on radials. If the same guy owned a TR he'd probably run 12.5's with the same mods. Because you can't doesn't mean noone can

All things equal, it seems a TTA will run around 3-4 mph and .2 faster than a TR. The gears, heads and aerodynamics all play a smal part. A difference, but not a huge difference. Put 28" tires on the regal and the difference will be smaller.

 

[Tow Man]

Originally posted by UNGN
I didn't even have injectors and ran 12.20's in my TR on radials. If the same guy owned a TR he'd probably run 12.5's with the same mods. Because you can't doesn't mean noone can

Well, You got my attention!

I have an 87 GN with the following mods; Big mouth cold air, 3" dual exh, 3" THDP, Thrasher 100, Walbro 340, adj FPR.

19 PSI boost, launching on slicks the best I could do is 12.90 at 105 with a 1.7 60' time! Hell, I thought this was pretty good until now!

Can you help me out?

I also have a bone stock TTA 10,000 mi. The TTA still "feels" faster than the GN. Haven't taken it to the track yet.

 

[UNGN]

to start, 105 mph means you need to lock the converter, use a chip with more timing in 3rd gear like a Thrasher 108 and maybe new valvesprings.

If I had to do my 12.20 era of my life over again, I'd use 28" tall tires and leave harder (more air in the airbag, a line lock so the brakes wouldn't get so over heated, etc.) I'm convinced those 12.20's could have been 12.0's or quicker.

 

[Tow Man]

Would locking the converter make that big of a difference? I forgot to mention, I do have air bags and new 100Lb valve springs. The car only has 22K miles and probably didn't need new springs, but better safe than sorry.

I run the air bags at 5 psi left and 15psi right. I launch at 10 psi. 10 psi is about all I can hold.

Aside from cranking boost to 23 PSI, and a race chip, I'm out of ideas where I can squeeze more out of it. I run the Thrasher 100 because I can get away with it on the street with a pump gas "mix". I run 112 octane leaded at the track!

I have most of the 11 second recipe sitting on the shelf but want to max out what mother Buick gave me first.

Sorry for picking your brain, but have to learn somehow! LOL

 

[rastaz]

Being an owner of both I can honestly say my TTA is a quicker car than my GN was with the same mods. I believe the TTA's advantage mostly lies in the heads and that they are generally 100-200 lbs lighter than most GN's.

 

[Tow Man]

Cleaner13 " I was just wondering what the difference was between the TTA and GN "

Sorry for steering the thread in another direction.

As Rastaz said, The heads flow better, they are much lighter than the GN (amount depends on options), and higher 3:25? rear gears give it an awesome top end charge

I'm sure the TTA guru's out there can give you all of the specific details. I remember a big TTA head discussion and comparison in the TTA section a while back. Try doing a search on TTA heads.

 

[turbov6joe]

As far as the GN/TTA comparable parts are concerned. The TTA has the GNX high efficiency intercooler, vacume brakes, and the FWD heads which soposedly flow better. The TTA has 3.23 gears verus 3.42 of the Regals, and has a smaller Borg Warner rear with a panhard bar and torque arm set-up, much like the GNX. The TTA has a cross drilled crank the TR's do not. The TTA has better designed headers that do not crack and a 3" single shot exhaust with a cross flow from the factory. The TTA came with a 237 fuel pressure regulator from the factory as well. The TTA has the 1LE performance brake and handling package, you know about the sucky Regal brakes/suspension. That's about all I can think of for now. I once owned a 10 second GN and sold that car to buy my TTA.
IMO, the TTA is all the things the TR's should have been and more!

 

[UNGN]

Originally posted by Tow Man
Would locking the converter make that big of a difference?

I've personally seen a stock injector car go from 108 to 112 mph by only locking the converter. No other changes. 108 had been the cars "best mph ever" too.

I've always "locked mine at the line", meaning I turn the switch on when I stage and the converter locks after the 1-2 shift. It's worth .2 and 2 mph in the 1/8th mile, so that can translate to even more for the full 1/4.

You need to have enough octane to overcome the load this puts on the 2-3 shift, though. I had the tranny gone through recently and had them inspect for any damage that racing a stock trans like this causes. In five+ years of abuse, the damage amounted to damaged splines on the stator shaft and in the original 90K mile D5 converter (you replace thos anyway), some signs of burning on the 2nd gear clutches and layer of clutch powder in the goo on the bottom of the pan.

Because of the low HP peaks, we either need taller tires, taller gears or both.

 

[19TTA89]

Hey Carl....It was nice meeting you...You left out one other thing..Im also running a ta-49...not sure of the diffrence over stock@20psi..But either way its a great turbo..I am actually going to try the stock injectors next time at the track with a thrasher 108 and some chernoble fuel.. .And hopefully pick up unough MPH to go 11's..We'll see...ILL shoot you an e-mail when Im heading to e-town next.....And thats a real nice GN you got there..Shawn....

 

[TurboDave]

Originally posted by Tow Man
Would locking the converter make that big of a difference?

You bet it will. If you've got a healthy converter, and a tranny that can take it. Locking the TCC (where I do, right after the 2-3 shift) nets me 4 mph in the 1/4

 

[Jebadias]

Originally posted by UNGN
You need to have enough octane to overcome the load this puts on the 2-3 shift

I never thought about that. I've been trying to tune my car in without locking the TC. I didn't want the extra wear on it when I was just screwing around. I suppose I need to start locking it up for tuning too eh.

 

[kenmosher]

As far as the gearing issue ...

The TTA has shorter tires than the TR, so the overall gear ratio is equivalent (stock for stock).

 

[TTA850]

Stock for stock the GN came with a 26.0" tall tire while the TTA came with a 25.64" tall tire,though switching to 255's out back is common and being 26.04" tall it brings everything back in line.

Steve

 

[RobR]

The TTA had a 2.75" cat back exhaust as stock, same as any other single cat TPI V8. The downpipe necks down to under 2" at a couple points to clear the frame/suspension.

As for locking the converter, here's my dyno comparison. Run 001 is unlocked and 002 is locked. This was back when it was stock(K&N, 160 thermo, Thrasher 92, cat pipe, valve cover breather)

http://mywebpages.comcast.net/tta1387/dyno.jpg

 

[UNGN]

Originally posted by TTA 1387
As for locking the converter, here's my dyno comparison. Run 001 is unlocked and 002 is locked. This was back when it was stock(K&N, 160 thermo, Thrasher 92, cat pipe, valve cover breather)

http://mywebpages.comcast.net/tta1387/dyno.jpg

Great graph! look at the difference in area under the curve with the converter locked. Torque is increased across the board.

Also note the hp and torque nosedive above 5K RPM. And this is with the slighlty better flowing TTA heads. More argument for steeper gears (ala TTA) or taller tires to keep the R's below 5K with a stock longblock.

 

[Snorman]

How do you lock the convertor? Can this be done via a chip?
S.

 

[UNGN]

Originally posted by Snorman
How do you lock the convertor? Can this be done via a chip?
S.

It can be done with the chip at a given mph or with a Switch as outlined on GNTtype.org

 

[Snorman]

UNGN,
Thank you very much!
Today, I think I'll do the TB bypass and TCC lockup switch.

S.

 

[1BADDAM]

The TTA has better designed headers that do not crack [/B]

They do crack. Trust me