Re: Not awake...cant think.. have the fever bad
vigman said:
So the 3:08's didn't do as much as I thought..It's better.. but the top end feels only slightly better ( engine rev's VS ground speed)
If I'm thinking correctly...
The only way out of this problem is an overdrive.. what are my options?
If I went with a shorter tire.. that would make my problem WORSE right?
They don't make 2:59's for a 64.. right?
( actually now a 1975 pumpkin)
So richmond.. here I come?
HELP!
Vig~
Ya know... Oh NO.. I never actually checked my OLD pumpkin ratio.. I assumed it was 3:70.... Oh I got a bad feeling about this...
DOH!
Vig,
You are starting to worry me. Grab a cup of decaf and hit the recliner. We need to talk about this. Pull the Rear End Ratio Caculator out of the Toolbox under the Tech Center tab at the top of the page and let's think this over.
With a 15" tire of around 27.5 inches tall, which would be a good average for a Mid Year compatable tire, you are only turning a little over 2600 rpm at 70 mph. 2200 at 60. I know you are going to build a new engine and this is at the bottom edge of the recommended cruising rpm of most modern profile street performance cams. If you slow the engine down much more you will end up having to slip the clutch to get it rolling and have to down shift to get the engine in the power band every time you want to pass or accelerate briskly. Sure the '81 and '82 had a 2.72 rear but the '81 4 speed had a 2.88 1st gear and the 700R4 of '82 has a deep low gear too. They also had the advantage of computor controls and cam profiles designed to work with this setup. I fear you are heading for a top end Bonneville machine that will be a slug in daily driving situations.
A mid year with a 327/300 horse, 4 speed and 3.36 rear gears is considered to be one of the best all around driver Corvettes of all times. 3000 rpm at 70 is not a bad thing. I used to pull 18.5 mpg at 70 in my '65 so equiped back in the '70s. This is not stressing a small block at all. Granted, these new high tech fuel injected, roller cammed and electonically controlled engines of today will pull strong from the teens on up but that isn't what we are dealing with here.
If your tach is showing a different rpm than the Calculator it may need re-calibrated. Not uncommon. (Something else for your list).
A 3.08 with a 1:1 4 speed is going to give you more top end than you will ever use and keep out of jail. In 1967 (here he goes with another old fogey story) I worked in Indianapolis during the week and went home to NE Indiana on the weekends. My ride at that time was a new '67 Olds 442 with a turbo 400 and 3.08 rear and a 2 row radiator. It had 14" 2 ply wide ovals that probably weren't any taller than 26.5 at the most . Maybe less. At the time I had to go north around 20 miles from town in Friday night traffic to pick up the interstate (I-69). It didn't go all the way to Indy yet.
After I hit the big road I would run a minumum of 90 mph and a max of 115, or 120+ if someone wanted to play, all the way home except for at Anderson where the cops were always sitting. Down to 80 there. The goal was US6 in less than 3 hours. This was a weekly thing for about 6 months weather permitting. Yes I was nuts. The car had 9 1/2 inch drum brakes that were useless. Hit them hard at 120 mph and by the time you slowed to 110 you had no brakes. From 65 a hard brake application would render them null and void by 45 mph. Sometime the good old days weren't so good; downright scarey.
I never broke or cooked anything and when I sold the car a few years ago to a collector it was showing 148,500 miles. Never apart and would still pin you to the seat.
Sorry for rambling but my point is the 3.08 is the highest (low numerically) I would consider going on your car if you plan on enjoying it both in town and on the road.
Tom
