Improve Performance For 79 TA With 403CI

[79TACONVERTIBLE]

I have a 1979 Trans Am with a 403 cubic inch (6.6L) engine.

It has the California emissions package, which reduces HP output.

Any advice about what’s involved and possible considerations to remove the CA emissions kit?

Any negatives about doing so (Car is no longer in CA).

 

[Pontiac Trans Am]

Are you looking to remove the equipment or disconnect and leave it on?

Thank you,
PTA Staff

 

[79TACONVERTIBLE]

That’s a good question.

Although I am not looking to sell it any time soon, would it hurt the value if I removed it but kept the parts?

I want to improve the car‘s performance.

The car looks fantastic, but frankly, it’s unimpressive power-wise.

Would there be any difference, performance-wise, disconnecting versus removing?

Based on the published stats, the CA emissions setup reduces HP by 30 or so. (I don’t live in CA).

What are the pros and cons of removing versus disconnecting if I want to further enhance by converting the 4 BL carb to EFI and EFI fuel tank, larger exhaust manifolds, etc.?

 

[79TACONVERTIBLE]

Are you looking to remove the equipment or disconnect and leave it on?

Thank you,
PTA Staff

Remove most likely.

 

[71 455 HO TA]

It appears your '79 has the Oldsmobile engine that lacked power, even without the California restrictive emissions.

Converting to an EFI, if correctly set up and tuned for your 403, would improve performance and get much better gas mileage than with a carburetor.

 

[79TACONVERTIBLE]

Thanks. Is this correct?

To convert to am EFI I need the EFI and manifold; a new, more powerful alternator & battery plus a new fuel tank with an electronic fuel pump.

Anything else?

Any recommendations as to brands and models for aforementioned?

What about recommended brand and model for improved headers and exhaust system?

 

[71 455 HO TA]

Your questions about upgrades to your 79 SO REMINDS ME OF MYSELF about four decades ago, when I began my life-long PMD F Body love affair.

I'm hoping I can help you make YOUR best sensible decision.

If driving a fun, fast car that gets excellent gas mileage with the pettiest cash spent in the shortest time possible is the goal ( And for me, that's what IS important ), your 2nd gen Convertible may not be the best choice for you.

Your ride is cool for sure, but it would take a CROWD of time and money to be a "FUN" car.

Go for a ride in a 1998 thru 2002 4th gen TransAm (or Formula) LS model 6-speed.

You'll be floored at their performance, and they get decent gas mileage when driven right.

I had daily drivers of a 70 TA in College in 1985, then in 1971, 455HO was my daily driver for about two years. I LOVED them; both were fast and fun, but they were Gas-Guzzlers, and it was expensive to drive; I could NEVER do it with current gas prices.

IMHO, "Dr. Oldsmobile" would cost a small fortune to do your upgrades, and it just couldn't replicate the LS engine's performance and economy.

You don't NEED to swap out five grand for a fantastic ride that has 40-year-old technology.

My first time diving a '98 Ram Air LS Formula with a six-speed was WORLDS ABOVE both of the earlier models I drove.

Drive what you want to drive; KNOW what you are in for with the MEGA-project your '79 would be.

 

[79TACONVERTIBLE]

Your questions about upgrades to your 79 SO REMINDS ME OF MYSELF about four decades ago, when I began my life-long PMD F Body love affair.

I'm hoping I can help you make YOUR best sensible decision.

If driving a fun, fast car that gets excellent gas mileage with the pettiest cash spent in the shortest time possible is the goal ( And for me, that's what IS important ), your 2nd gen Convertible may not be the best choice for you.

Your ride is cool for sure, but it would take a CROWD of time and money to be a "FUN" car.

Go for a ride in a 1998 thru 2002 4th gen TransAm (or Formula) LS model 6-speed.

You'll be floored at their performance, and they get decent gas mileage when driven right.

I had daily drivers of a 70 TA in College in 1985, then in 1971, 455HO was my daily driver for about two years. I LOVED them; both were fast and fun, but they were Gas-Guzzlers, and it was expensive to drive; I could NEVER do it with current gas prices.

IMHO, "Dr. Oldsmobile" would cost a small fortune to do your upgrades, and it just couldn't replicate the LS engine's performance and economy.

You don't NEED to swap out five grand for a fantastic ride that has 40-year-old technology.

My first time diving a '98 Ram Air LS Formula with a six-speed was WORLDS ABOVE both of the earlier models I drove.

Drive what you want to drive; KNOW what you are in for with the MEGA-project your '79 would be.

Thank you for your advice, as I took it to heart.

So far, here’s what I have done: Removed the smog pump, put in new, larger exhaust headers/manifold, and rebuilt the exhaust all the way back to the tailpipe, including having a true dual exhaust all the way back.

In addition, I put in a new transmission torque converter and 3.40 gears / posi traction in the rear axle.

This brought my HP and Torque to 260/325 vs. factory for this California-compliant model of 185 and 315 (respectively).

The distributor and carb needed rebuilding.

In all, the cost was about $7800 for parts and labor.

This was my first step towards performance improvements.

If it seems fast enough, I will stop there.

If not, I will explode hydraulic lifters, valves, rings & cylinder heads.

Right now, I am just going to enjoy it.

 

[Mhack1]

Thank you for your advice, as I took it to heart.

So far, here’s what I have done: Removed the smog pump, put in new, larger exhaust headers/manifold, and rebuilt the exhaust all the way back to the tailpipe, including having a true dual exhaust all the way back.

In addition, I put in a new transmission torque converter and 3.40 gears / posi traction in the rear axle.

This brought my HP and Torque to 260/325 vs. factory for this California-compliant model of 185 and 315 (respectively).

The distributor and carb needed rebuilding.

In all, the cost was about $7800 for parts and labor.

This was my first step towards performance improvements.

If it seems fast enough, I will stop there.

If not, I will explode hydraulic lifters, valves, rings & cylinder heads.

Right now, I am just going to enjoy it.

Did you fill in the 4 threaded ports on each side of the block from the old exhaust?

 

[79TACONVERTIBLE]

I had a professional performance shop do the work, so I am unsure.

I did get the impression, though, that where the headers attached were an exact fit, so the holes would have lined up and reused.