TonyPie

Has anyone replaced their 77 floor pan with a 70-74? I was told by a professional that it can't be done. My friend was told it can with some modifications.

Philhawk02

like with anything else, enough time and effort could make it work, but if I remember correctly the 75 model year had a subframe that was narrower in the back, and a smaller tranmission tunnel because you couldn't get the TH400 anymore so there was no need for it to be so big. I know they floor pans are listed differently, come in different sizes and look different. I'm sure someone can give you a better explanation and correct my mistakes. The parts or cheap enough to just order the correct pan though.

JohnnyBs98WS6Rag

iTrader: (1)

I think they had to modify the floor pan in '75+ to accomodate the (then new) catalitic converters. I'm not so sure about the narrower subframe thing. But if they discontinued a trans in '75, they may have shrunk the tunnel then while they were at it re-tooling for the cat. I'm betting if you don't run a cat, an earlier floor pan might work.

Camaroholic

iTrader: (1)

Yah, remember back in those days, the cats were HUGE. I seem to remember the single cat being about 18-20" long and like 16" wide, and 3-4" thick.

As for subframe differences, I did bolt a 79 subframe on to a 73 body, I seem to remember having to do "something" to the subframe, but all 4 body bolts did go in - so at least that much matched up. Ah well, that was too many years ago. Though I think it had to do with the rear bolts on the subframe being in a different location, so I had to cut or notch new holes or something.

TonyPie

Thanks for the help, I'll take your advice and purchase the 77 floor pan. The 74 was offered to me at cost, that's why I was thinking about it. Again, Thanks!

JohnnyBs98WS6Rag

iTrader: (1)

True 'dat. Just last summer I finally tossed out the cat I hacked off my '76 when I bought it 20 years ago. I have no idea why I had been keeping it, but it was huge by comparison to the little bread-loafs we have now, and it weighed like 70 lbs! In fact, I had also tossed the cat that was originally in the trunk of my '77 Camaro LT (replaced by a "test pipe" by prior owner) that I found sitting in my garage next to the one from the '76. It was much smaller, more like our modern cats. Not sure if the smaller size was due to tech advancements between '76 and '77 (doubtful) or due to the '76 being a 455 and the '77 being a 305. Both stock systems used a Y-pipe to a single cat, back to a 1-in/2-out muffler above the axle. I do remember that the '77 Camaro sounded much better than the T/A, even after I replaced the T/A's exhaust w/ a '74 non-cat system (dual pipes back to a 2-in/2-out muffler).