CK5
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Crusing Speed RPM
- Thread starter CHEVY 4WD
- Start date
well with my 3.73s and 36"s i run about 2200 at 65. but i'm going to 4.56s soon which will put me at about 2800 i think.
Shaggy
3/4 ton status
<font color="green"> Anywhere between 2200-2800 is fine. Even as high as 3000 should be OK. Maximum effeciency, IIRC, is around 2400. Lower than 2200 it might bog a bit when you pass. </font color>
</font><blockquote><font class="small">In reply to:</font><hr />
Lower than 2200 it might bog a bit when you pass.
[/ QUOTE ] it does /forums/images/graemlins/frown.gif
Lower than 2200 it might bog a bit when you pass.
[/ QUOTE ] it does /forums/images/graemlins/frown.gif
87sm465np208
1/2 ton status
my cruiseing speed with my 1:1 ratio in the 465 and the 3.08 gears puts me at about 2K rpm at 55mph, so yea OD does help on those long trips, unless yur pulling a heavy trailer. /forums/images/graemlins/thumb.gif
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89GMCSuburban
1/2 ton status
I found 2200 to be perfect for me. With my 31's and 4.10 gears (was cheating, I have a 700r4), I cruised about 2200 at 70. Now that I'm getting 36's, I wish I'd gone 4.88.
MilpitasK5
1/2 ton status
So would it be safe to say that 1600-1700 in OD is bad for my junk? I've have had this coversation with others and haven't used OD since.
GMslave
1/2 ton status
Whoa, hold on!! You said </font><blockquote><font class="small">In reply to:</font><hr />
I turn 3K and am doing about 70.
[/ QUOTE ] Are you sure? Cuz I turn 3000 at 70 mph (as per GPS and Autometer) but I'm on 35's. Your bio sez you're on 33's with 4:10's, has that changed? I assumed I had 4:10's in my 77 3/4 ton, but that doesn't seem to make sennse. Did the factory offer 4:56 stock? /forums/images/graemlins/confused.gif I've never had the covers off of it, and now it's freezing outside. Does this seem right to anybody?
I turn 3K and am doing about 70.
[/ QUOTE ] Are you sure? Cuz I turn 3000 at 70 mph (as per GPS and Autometer) but I'm on 35's. Your bio sez you're on 33's with 4:10's, has that changed? I assumed I had 4:10's in my 77 3/4 ton, but that doesn't seem to make sennse. Did the factory offer 4:56 stock? /forums/images/graemlins/confused.gif I've never had the covers off of it, and now it's freezing outside. Does this seem right to anybody?
I ran my 383 a lot around 3K rpm since with 3.73's my overdrive wasn't much use. I didn't have the best motor longevity, I had cam bearings crap on me and the piston fit isn't that great anymore. This is within about 100K miles over the span of about 7 years and I wasn't exactly gentle with it. I ran some pretty big passes on a regular basis as fast as the truck would go. It is a short rod setup.
In my 'burb with the 4.56's and 315/75's in OD it runs OK but could still use more power. I figure I'm doing 2250 to 2300 rpm and more wouldn't hurt. 4.88's or 33" tires would do the trick I think, or adding some more power. I have a stock EFI 350 in the 'burb.
In my 'burb with the 4.56's and 315/75's in OD it runs OK but could still use more power. I figure I'm doing 2250 to 2300 rpm and more wouldn't hurt. 4.88's or 33" tires would do the trick I think, or adding some more power. I have a stock EFI 350 in the 'burb.
