Quest for 9's

[forcefed3.8's]

245" Weber stroker girdled with stock caps
224 billet roller
old casting GN1's ported by myself
1.65 T&D's
cometic headgaskets
GTQ76 turbo
home ported stock intake
stock throttlebody, Hemco upper
Cotton's front mount
Pete Tomka 4" intake with 4" drop in Z06 sensor
95lbs injectors
ATR double pumper
3.5" TH DP and single exhaust
stock headers cut open and ported by myself
0 pump 5 disc Vigilante 3000 stall
Full billet Janis trans
Eaton Posi, 30 spline Moser axles, C-clip eliminators
21psi 20deg timing 8psi launch shifting at 5400
1.48 60'
6.52@106 1/8
10.20@134 1/4
The car went 6.49@109 at 25psi running dangerously lean before. It was running lean here as well from a user problem with the translator:redface:. I got the translator and wideband tracking figured out, hopefully I can get one more trip with more boost before the snow flies. It is impossible to tune on the street, not to mention unsafe. Traffic and turns come up in a hurry.

 

[BEATAV8]

Are you going to try shifting at a higher RPM next time out? That cam will go a lot more than 5400.

 

[forcefed3.8's]

I was planning on running it out some this past time, but I was trying to figure out the fuel issue. I figure shifting around 6000 might help out some.

 

[79TurboCutlass]

I was planning on running it out some this past time, but I was trying to figure out the fuel issue. I figure shifting around 6000 might help out some.

I'm scared of RPMs. You'll get there. That thing is an animal.

 

[GNBRETT]

Sounds like a beast. Must be fun on the street.

 

[forcefed3.8's]

It's useless on the street. 21psi breaks loose 28/10.5 slicks. Drag radials, forget about it. 25psi makes the slicks feel like drag radials. I am doing a frame notch and some suspension work over the winter. I would like to do a PTC converter and a transbrake, but like the driveability of the Vigilante. It feels stock, I know a PTC will be sloppier around town. It would be easier to race with a looser converter though. The car is so nice to drive anywhere, it is stupid. I have only had it to the track twice this year, but have driven it to work, car shows, store to buy beer all summer. For the size of the turbo and converter, it comes up on boost pretty quick. I can't wait to crank up the boost again. I might run TSE at BG unless I get carried away with the notch. I really want to fit 315/60's. I would just be happy with making it to BG for the first time. I have been racing this car since 1998.

 

[BEATAV8]

I would like to do a PTC converter and a transbrake, but like the driveability of the Vigilante. It feels stock, I know a PTC will be sloppier around town.

I'd give the 9.5" PTC more credit than that. I have one in a deep 10 car and it drives very nice around town. Just like a vigilante... it's no big deal for drivability.

Originally Dusty gave me a PTC 19-27, which was too loose for my combo. Even that one drove nice though. I switched to a 17-27, which is 400 RPM tighter. The 17-27 pulls the engine down to ~5000 on the shifts and gives me an extra 20mph worth of 2nd gear over my old Vigilante, and only 7% slip through the traps. When I say "an extra 20mph", I mean it shifts 2-3 at 70mph instead of 50mph. Gotta love that. The 17-27 converter combined combined with a KC valve body and a BR governor shifts all by itself at 6k RPM. Just wanted to bring that up because if you do change to a PTC, be ready to re-tune your governor (or switch to a KC VB) along with it.

 

[Super6]

Ptc

yes the PTC is great around town..i love it...it's loose but that's what is fun. i just put a new set of 275/60 MT drags on mine and it hooks great even on the street..get a new set of MT's and try them....Bob

 

[forcefed3.8's]

I have MT slicks and drag radials 275/60. They both break traction like crazy. I also have a set of BFG DR's 275/60's that might as well be coated with oil. I would like to do some governer modding to up the shifts. The trans is coming out this winter for freshening, so maybe a PTC will end up in there. The 0 pump Vigilante works great as far as rpm drop. I would just like quicker at the tree spool up for bracket racing.

 

[Dusty Bradford]

I think you'll be suprised how well the driveability of the 9.5 compares to your Vigilante if you decide to swap to non lock. It will most likely spool faster than your current converter yet drive very similiar. There are several guys in your area running them. You might try getting up with some of them to see what they think.

 

[forcefed3.8's]

I will probably switch this winter. Two of my friends are running PTC's. One has a big 4 bolt 76 TSL turbo and the other a 66GTQ. I am not sure how they would compare to what would be spec'd for my combo. I would love to have a PTC and a transbrake next year.

 

[Dusty Bradford]

Anything with a 76mm on 245ci will have to be fairly loose. The car with the 4 bolt 76 would be a good comparison. For great driveability a smaller turbo like a 70mm could be used but the 76 is still very streetable.

 

[Super6]

Ptc

my car spools up fast on the foot brake or trans brake..i have the .81 4 bolt housing on mine..Dusty hit my car right on the first time....Bob

 

[Super6]

believe it or not my DR's hook better than my slicks on the street..the slicks are 28.5" by 10.5" Phoenix..not sure if the DR's will do better at the track..only have one pass on them..i will find out in Reynolds.....Bob

 

[forcefed3.8's]

It would be interesting to see back to back DR vs slick times. I have heard DR's roll out better, so will require less boost on launch to 60', and also mph more. I am going with Hoosier DR's next year. I heard they hook better and are lighter than M/T's. I am either going with a 315/60 or 325/50 with a full notch and a mini tub.
At 21psi, the slicks and MT DR's aren't too bad. At 25psi, the car is all over the road.
I want to switch to a PTC, it all depends on how much I end up dumping into a cage and suspension work this winter.