[Speargun]

I finally made my first trip to Gainesville Raceway today with my '67 Firebird for test & tune. This was the first time I've run down the track in over 30 years, but it's just like riding a bicycle.

In full street trim and a set of wore out Nitto 555's, my first pass down the track was 12.42 @ 112mph. With 20 psi in the tires, traction was non-existent until I pedaled it out past the 60' which was 2.047.

I ended up making 7 passes with the best of 12.02 @ 113.58 and a 1.84 60'.
Most of my 60' times were from 2.04 to 2.12 & the ET's were around the 12.40 mark but almost every run was in the 113.xx mph range.

My last couple of runs I noticed that the TH-400 was taking it's sweet time to shift into second and the trans temps were in the 210-240 range at the end of the runs. The last run I hit 2nd gear & the rpm's kept climbing I ended up double bumping it right into 3rd. This netted me the worst run of the night at 12.802 @ 111.21 with a 2.070 60'.
I thought it odd that I totally skipped second gear and only lost 2 mph.

By my 4th or 5th run the track was covered in water, sand, & marbles. The crew never blew it off and the mini Coopers & Honda's had drug half the parking lot onto the groove.

I think that there is close to another second to be had out of this car with a couple of changes. I was running a Victor intake tonight which is probably more than what the car needs so I think I'll switch back to the HSD or Torker II & see how things run.
I need new tires. The Nitto's did best with 16 psi, but the center section is about gone and wasn't near as sticky as the outside, less worn, sections.

The Caltracs were in the bottom hole with about 1/8 turn pre-load on the split mono's and the car seemed to launch & run straight. There are cheapo Summit adjustable shocks on the rear set on the softest setting and the QA-1 coil overs up front may need a little tweaking, but seemed to be okay where they are.

Besides swapping the intake & new tires, do you have any other suggestions?


My Combo:
'67 Firebird w/AC
VFN "Tony Orts" 4" bolt on glass hood

455+.060 - 469cid
Fitech 1200pa
Victor Intake
72cc E-heads with gasket match only
Block was decked & squared with the BRC 23cc dish pistons .003 in the hole
Static CR= 10.23:1 - Dynamic CR=8.65
HR camshaft = .583/.561 236/248 @ .050, 106CL & 110LS
Continental tight converter 3200-3400 stall, but flashes 3600.
TH-400, Dana 60 with 3:54 posi.
Nitto 555 275/60 R15
Doug's headers with 1 7/8" primaries, Pypes 3" X pipes through Dynomax turbo mufflers to rear quarter exits.
MSD is controlling the timing with a base of 18* that ramps up to 26* - 28* @ 1800 or 2000 rpm, then jumps to 36* by 3400 rpm. (iirc)

The dyno says...........
410.25hp @ 5200 & 459.18tq @ 4350 at the wheels.

[dragracerx2813]

I would start with tires first. Then go back and see where your at. If you go and make a bunch of changes before you go to the track, you won't really know what worked and what didn't work.

[prostreet64]

Ditto. I would work on traction first. Sorry you had so much trouble with trying to get the car hooked up. Prep at Gainesville Raceway can be anything from great to non-existent. A lot of street cars makes it even more of an issue. I usually try to make my first pass as soon as the lanes are open, and then right after they do the mid day cleanup and respray. I would start with tires for sure and then go from there. Would like to be at the track when you make your next test and tune so we can compare notes. Maybe my son can have his 69 there as well.

[ponyakr]

Wouldn't even attempt to make any serious track runs with that much motor, without big sticky tires.

At the very least, I'd run the M/T DOT street radials. And those only if I had to drive to the track with 'em. Better to run real slicks. I'd run the biggest tires that will fit on the car that won't rub. The rule of thumb is that the softer the rubber, and the bigger the contact patch, the better the traction will be. I don't see any way you can have too much traction.

We never had Cal-trac bars. All we ran were slapper bars, some of which I made, because of low budget. Ran some no-prep tracks/airport runways. I added weight in the trunk, to help traction on the really bad tracks. I raised the body with shackles & ran 13 x 30 slicks. To me, bigger was better.

Since this is the race section, I don't know if this is a street car, street/strip, or strip only. And don't remember reading your gear ratio. Anyhow, if I was gonna try any competitive bracket racing, I'd pick the tallest slicks made, that won't rub the fender, in the widest tread width available, even if they stick outside the body slightly. But there are quite a few '68 Bird Stockers running mid tens with 9 x 30's, Cal-tracs, & spit mono-leafs. BUT, those cars run on well prepped tracks with sticky starting lines.

https://www.summitracing.com/parts/hoo-18150d06

https://www.summitracing.com/parts/hoo-18155

If a 28" won't fit, here's a 26.4".

https://www.summitracing.com/parts/hoo-18131

Here's a pic of one of our low buck '68 Birds, launching at the Tyler TX track. TJ won lots of races with this car. We ran the same rear tires/wheels on both cars, so we'd only have to carry one spare with us. Couldn't afford narrowed rear ends with tubs & 14 x 32 slicks, like most of the quick cars had. But we did OK, considering the low budget.

[prostreet64]

Curtis and I run the M/T 275-60x15 drag radials, dot rated. They have worked very well for us since we drive our cars on the street and to the track. On the '69 I believe the wheels have a 4.5" backset and that puts the tires nicely in the wheel wells; IIRC I did trim a 1/4" off of the upper wheel well lip to give a little extra clearance.

[ponjohn]

You have enough mph for 11.80's and the combo looks like it could run in the low 11's.

I'd work on the 60 ft. New tires, loosen front end.

Great you had fun.

[dragracerx2813]

Originally Posted by prostreet64

Ditto. I would work on traction first. Sorry you had so much trouble with trying to get the car hooked up. Prep at Gainesville Raceway can be anything from great to non-existent. A lot of street cars makes it even more of an issue. I usually try to make my first pass as soon as the lanes are open, and then right after they do the mid day cleanup and respray. I would start with tires for sure and then go from there. Would like to be at the track when you make your next test and tune so we can compare notes. Maybe my son can have his 69 there as well.

Gainesville track prep on TNT nights isn't the best . If you go on a point race night , the track will be much better .

[Torquewar]

Nice car and more potential. I agree ...tires first and suspension mods. Your 60 ft can be cut to 1:60s... takes some time .
You easily have a mid 11 ride.

[Scott Roberts]

Make one change at a time....you have plenty left in that combo!

[68blackbird]

A set of loose front shocks will help a lot. I thank Cal Tracs recommends 5+ inches of up travel. I had worn out shocks, changed to some 90/10 shocks and was surprised how well the car hooked. I don't have the power you have, but losing the front and tires should make a massive difference.

[Mark G]

Well congrats ..as long as you know if bitten by the bug there is no known cure for the disease.... ..

[chiefbigb]

Tuning seems to take a while. Weight transfer and decent tires as stated should net you good results. You have allot of torque. Once you get the 60ft under control work on shift points timing and jetting.

[straycat]

As mentioned tires will get that 60ft down and along with that are lower ETs. That mph says 11s possible.

[Speargun]

Since most of my miles are on the street, I'm going to order some new Nitto 555r's & see if I can find a set of slicks for the occasional track visit.
I think that with the right intake & good traction, the car should run an easy 11.50 or better.

Thanks for all the tips! Keep 'em coming.

[Torquewar]

Should be interesting with new slicks....keep us posted. The 2 best things i did was to free up the control arms and installed coil overs (UMI ) with adjustable compression /rebound. I went to tubular arms last winter. It all helps with weight transfer . Once the racing bug bites ... i budget for the components that are bang for the buck.
I may get in 30+ runs a yr so the shocks work well for what im doing.
I was struggling like yourself ...180..sometimes worse, now 155-160 s . Im running 11.0 s and a fist full of 10: 90s . Not a blistering fast race car but its sorted out. Of course the track prep dictates the outcomes..