I have a question......... I have a 78 camaro with a 402BB and a powerglide trans. When I hit the street, it seems to hit the RPM's a little on the high side when im driveing down the road and eating up a crap load of gas. My question is this..... Should I change the trans to a 3 speed or should I change the gears in the rear end. There are 410's in the rear now. I would like to do it the easiest and cheapest way possible. I DONT want to lose to much on the low end take off but.... whatever has to be done. Thanks for ANY help.

 

How much money do you have to spend? Swapping out the powerslide for a t350 will only give you one more intermediate gear. Final drive is the same for both, 1:1. So your "down the road" rpm's won't change, nor will your crapload of gas situation. Considering your 402 has a lot of grunt, I don't see a trans swap as being very beneficial for what you're after.
4.10's are fun. That's what I have, and I wouldn't want to go with a higher ratio. But I plan on replacing my t350 with a built up 700R4. An overdrive trans will give you the best of both worlds, a nice low first gear which would be noticeably lower than what you have now, and overdrive to lower the highway rpm's a good bit.
I would price out both a gear change and a trans, then decide which is more important to you.