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Architecture owns me
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2,351 Posts
Discussion Starter #1
would I be turning? With 30" tires and 4:56 gears? In 4th gear of a old '68 k20?

I know it's a weird question and I don't even know if I gave near enough info, but I figured someone might know an average.

My dad drove home the '68 for the first time yesterday since we bought it in pieces and he said at 45mph and in 4th gear it felt like he was turning at least 3k rpm's.

Here's the only pic I have and it's an unfinished pic I haven't got any finished pics as it's not totally finished, but licensed and driveable.

actually now that I realize it I never took and full on shots during the build so this is the best for now:
IMG_0102.jpg
 

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Architecture owns me
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2,351 Posts
Discussion Starter #2
OOO and btw I wouldn't have to post this if it didn't have a tach. so there's a heads up
 

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The Green Seal
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3,721 Posts
trans?
 

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GMFS slowest truck :read:
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5,501 Posts
4 speed manual (1:1 4th gear) would put it at about 3300 rpms at 65.
 

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Architecture owns me
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2,351 Posts
Discussion Starter #6
Sorry forgot to mention it's a 4spd

4 speed manual (1:1 4th gear) would put it at about 3300 rpms at 65.
Well I know he wasn't going anywhere above 50 and he said he had his foot to the floor and he couldn't get anymore out of it because it sounded like it was already turning 3k rpms. I think we are going to get a tach. for it.
 

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Bayou Surface Drive, LLC
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7,077 Posts
50 mph= 2555.924 in 1:1
55 mph= 2811.516 in 1:1
60 mph= 3067.108 in 1:1
65 mph= 3322.701 in 1:1
70 mph= 3578.293 in 1:1

This is my program i made to calc out rpms. I had posted it up for you guys to DL to your comps. but those are accurate only if your tires measure 30" rolling circumference.
 

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Architecture owns me
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2,351 Posts
Discussion Starter #8
Ok thanks for the info I'll have to relay it to my pops
 
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