1980 Trans Am (Again)

**GTP231** · 02-03-2010, 01:38 PM

Originally Posted by wheeliE-maxx

That was the "will still be a turd" part of my post

Ahhh still left out the worthless part though

***SMWS6TA*** · 02-03-2010, 01:38 PM

Gut engine, fix rust, install LS6, new paint = win

just my .02 cents

**big hammer** · 02-03-2010, 02:56 PM

Originally Posted by GTP231

The 8.5:1 compression will still be a worthless rusted slug even after that and not worth it

it would be lucky if it's even 8.5:1

i think the 454 in my truck is 7.8-ish. i'm running a 150 shot on 87 octane. it's sweet.

**wheeliE-maxx** · 02-03-2010, 03:03 PM

I think olds were at 8:1. Switch to some earlier 350 olds heads if they have closed chambers and bam you're back in business. 403 has a bigger bore than a 454 chev, it the heads will allow for breathing it will really breathe. Bottom end is fragile

**wheeliE-maxx** · 02-03-2010, 03:06 PM

Note: The information contained in all of the "Engine Detail" sections should be read before proceeding with modifications, etc., because some information that applies to all engines, or all small blocks or all big blocks, might not be duplicated in every section.

The 403 was made from 1977 to 1979 and used across the Buick, Olds, Pontiac and Cadillac vehicle lines. It was also used in other applications like motor homes, boats and some industrial applications. It was sort of meant to replace the previous use of big block engines in the BOP line. Stock specs on a 1977-79 403 are: 185hp@3600 RPM, 320ft/lbs torque @2200 RPM, 4.351 x 3.385 bore/stroke, 8.0:1 compression ratio.

Big pistons and a short stroke are an excellent combination for a high-RPM engine, but here the other inherent 403 weakness comes into play: Windowed main webs, and to a lesser extent, siamesed cylinders. The bottom end of this block is not suitable for extended use at high rpm with very high cylinder pressure.

**justinmc978** · 02-03-2010, 04:10 PM

after reading this entire thread i would say $2-3.5k would be fair, i like the 79-81 nose second to the 70-73 nose, i would keep it the original dark blue color with gold accents, trash the old motor an go with an LS-, theres 2 more cents

**fbod91** · 02-03-2010, 04:19 PM

Originally Posted by wheeliE-maxx

Try women instead of getting a new car. They are generally smaller and lighter. Also with an old car nine times out of ten there is more problems than you think. You will also get raped on fuel.

yep and enines blow on them sometimes too

**SHines-IT** · 02-03-2010, 04:26 PM

Originally Posted by justinmc978

after reading this entire thread i would say $2-3.5k would be fair, i like the 79-81 nose second to the 70-73 nose, i would keep it the original dark blue color with gold accents, trash the old motor an go with an LS-, theres 2 more cents

Hey, you think like me. I always wanted a late 2nd gen in that dark red color or NBM... Then an early second in and white/blue.

**big hammer** · 02-03-2010, 04:27 PM

Originally Posted by wheeliE-maxx

I think olds were at 8:1. Switch to some earlier 350 olds heads if they have closed chambers and bam you're back in business. 403 has a bigger bore than a 454 chev, it the heads will allow for breathing it will really breathe. Bottom end is fragile

olds engines were bearing eaters if you fed the rpm to them

you can even put 5.7 diesel heads on the 403--- REALLY gain compression... lolz