1972 Thunderbird 429

Picked up a 72 Bird. LOVE this car as a king sized luxury sports car! Ive had the trim removed. Body cleaned up. Painted. Looks the part now, not a grandpa cruiser! I can burn rubber from pure power but the car is not fast... at all...

I drive it daily to and from work. Would like the ability to pass on the freeway.

Need more juice from the 429 2bbl...

Thinking:

Holley 670 4bbl
Weiland Stealth 8012
Lunati voodoo cam 10340702
Lunati springs/retainers/locks 73815k5
rhodes lifters 9008
summit gear drive SUM-G6712
Hooker Headers HOK-6126HKR
(will have to do header back custom since no kits available)
B&M shift kit BMM-40262

Thoughts?

I would drop the gear drive and go with a good double roller chain and get holley 750 vacuum secondary carb

From what I have heard/read, a regular Edelbrock Performer 2166 intake would be a better choice compared to the Weiand 8012.

69F100 wrote:I would drop the gear drive and go with a good double roller chain and get holley 750 vacuum secondary carb

X2

Add some gear to it??? 3:50 or so???

You've got a real land barge, there. Very cool ...very comfy ...very heavy . It's a good thing that "fast" is a relative term.

Seriously, keep the power peak down low to get the acceleration you're after. Keep the gearing sensible and rely on the downshift for that freeway passing ability.

X3 on ditching the gear drive.

Hey thanks for the replies!! yes it is a dang OX!

Whats the knock on the gear drive vs double roller? from my research the gear drive is more durable and the chain drive requires adjusting. no dyno proven HP loss to my knowledge unless someone can point me in a different direction.

Also i have the Holley 670 already... whats the loss in that over the 750 in this application? Im not opposed to selling the 670 and buying a 750 was just using what i have if no noticable difference.

As for re-gearing. Whats involved there? part numbers to hunt?

Thanks all!

The gear drive transmits bad harmonics from the bottom of the engine into the valve train. Timing chains are proven for millions of miles in production cars, and never need adjusting even if you could. As far as the carb the 670 is only 170 cfm or so bigger that your 2bbl carb. A standard Autolight 4bbl carb is around the same cfm. Get the bigger carb and nix the gear drive, get the dist. recurved, add some gears and have fun. Oh and if you want to go crazy port the heads a little and get a quality 3 angle valve job.

okay thanks.

listened to some gear drive clips and the sound is not pleasing. will swap out the gear drive for the:
Cloyes Street True Roller Timing Set

save a few bucks too.

as far as gears, have part number recomndations for whats being suggested for this whale? I guess a factor would be the weight... Close to 5000#s with driver. and tire size:
rear: 255/55/18
front: 225/55/18

ThunderCat wrote:okay thanks.

listened to some gear drive clips and the sound is not pleasing. will swap out the gear drive for the:
Cloyes Street True Roller Timing Set

save a few bucks too.

Make sure the timing set you get is for a pre-72 application. The factory replacement set for a 72 retards the cam timing which hurts performance.

ThunderCat wrote:as far as gears, have part number recomndations for whats being suggested for this whale? I guess a factor would be the weight... Close to 5000#s with driver. and tire size:
rear: 255/55/18
front: 225/55/18

If it was mine, I'd put it together with the gears that are in it, then drive it a while to decide what gear change is necessary.

While You could wait until you do the engine mods then see what gears you need, but with that wheel and tire combo I think you are leaving a lot on the table. That tire/wheel is almost 29" in diameter, coupled with a stock 2:70-3:00 gear it will not accelerate like it did when stock with 24-25" stock tires. There are plenty of calculators on line to help figure out the optimum gear ratio with your tire and wheel combo.

If you have a 9-3/8ths differential , finding gears will be tough. Good thing is a 9" 31 spline diff will drop in it's place.

some cars just look like Ch*t with those big wheels, like putting bicycle tires on a semi.....

the Coug wrote:some cars just look like Ch*t with those big wheels, like putting bicycle tires on a semi.....

I can see that said about 20s and larger on older cars. I don't think 17s and 18s are bad. Especially if you can put some tire on them. Not running rubberbands here...

Timing sets are for the engine series so years span the production. The Cloyes is same pre 72 as 72. Should be good right?

Make sure the timing set you get is for a pre-72 application. The factory replacement set for a 72 retards the cam timing which hurts performance.[/quote]