1979 Pontiac Trans Am 4 speed

1979 Pontiac Trans Am 400 4 speed WS6 . We all know a 400 cubic inch motor will roast the tires, so I just did a quick 0-60. You can hear the tires 255/60/15's protesting through 1st gear. Love that Pontiac torque.
Original 400 engine which is low compression 8.1.1 with a Compcam XE 256 and headers. Enjoy.

Category:

Autos & Vehicles

Tags:

• 1979
• Pontiac
• Trans
• am
• 400

[Dhoylandrules84]

I know the 403s real problem is their heads and cam but im just trying to get an accurate idea here. Im new to these motors so im trying to get a hang for them. Im thinking probably 10 to 20 horsepower and a noticably improvement in throttle respone and smoother idle. What would you think?

[mattspontiacta]

A cam with a duration of 212 -218 duration @ .050 would really wake up the engine. Probably close to 25 hp. Headers would add another 25-30hp over the factory set up. This power can be acheived with the current heads and low compression. Bump up the compression in the 9.5.1 range and step up the cam to a 218 intake / 224 exhaust, and you would have a real strong performer.

[Dhoylandrules84]

Those stock 79 400s rated at 220 horse were underrated right? I heard from a few places they has closer to 300. You think thats true? Your car really took off nice. I know you got some mods like a cam and stuff but you still got low compression and it seems real healthy. I got a 403 in mine. Love these cars

[mattspontiacta]

The 1979 TA 400 were rated at 220 hp. Pete McCarthy often refered as the "pontiac bible" person said these motors actually were closer to 260hp from the factory.

Desktop dyno 2000 program with my engines specs produced 313 hp and 415 TQ at the flywheel. Torque is what these motors produce very well. Over 400 TQ from 2000 rpm to 4000 rpm. These cars are also close to 4000 lbs. The 403 Olds is a good motor and respond well to the same mods as a Pontiac 400.

[mattspontiacta]

Headers -Hooker SC's 1 3/4" primaries,

New OEM Dynomax turbo mufflers (they are small ) then the factory tailpipes.

[TheMKEWERBY]

That's STOCK? WOW!

[grngs1]

Mine had 185 hp

[MrTransAm1979]

@Dhoylandrules84 im guessing only some 403's had problems mine has over 500,000 miles and its still making the tires cry

[tonidmc]

Beautiful and powerful T/A!

[Dhoylandrules84]

woah thats crazy torque for a late 70s motor no wonder why they could still do 0 to 60 in 6 seconds with a 220 rating. Thanks for the info. Also as for my 403 i just put in a new blue printed dist with a ignition curve and a 55k coil and welded in two flowmaster 40 series in place of oem type muff on a older true dual system with no cats. My compression is good in all cylinders so what would you think im making for power realistically with that set up?

[bugdewde]

Wow... that's my car exactly. Nocturne blue, blue decals, silver 8" wheels....I have camel interior. '69 block but with stock W72 heads and equipment. No headers. Torque monster. Check out my vid