Worried I am hurting my car. Am I?
#22
TECH Senior Member
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
You'll snap off the landings inbetween the ring groves if you labour a motor too much for too long.
I worked for an engine builder and we had a few yonger fellas engines come in.
Mainly RB30's out of Holden VL commodores (old Skyline motor)
They drive around town in 5th gear at 50km/h (30mph) labouring them to make the exhaust rumble real low and the piston ring landings must vibrate too much and snap.
They stay in place and just float around
Best bet would be copy close to an auto's shifting points if your worried.
But in saying that, whats better than a rebuilt or new engine
I worked for an engine builder and we had a few yonger fellas engines come in.
Mainly RB30's out of Holden VL commodores (old Skyline motor)
They drive around town in 5th gear at 50km/h (30mph) labouring them to make the exhaust rumble real low and the piston ring landings must vibrate too much and snap.
They stay in place and just float around
Best bet would be copy close to an auto's shifting points if your worried.
But in saying that, whats better than a rebuilt or new engine
#23
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I shift at 2k. Averaged 22.6 mpg last tank 60% city 40% highway.
The tank before doing the same driving with a little more highway beating on it got 17 mpg. I believe its better on the engine to shift it early than to beat on it from every stoplight.
The tank before doing the same driving with a little more highway beating on it got 17 mpg. I believe its better on the engine to shift it early than to beat on it from every stoplight.
#24
12 Second Club
iTrader: (16)
Join Date: Mar 2008
Location: Amarillo, Texas
Posts: 444
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
well my friend has heads cam tuned m6 ss and he usaully shifts around 1800 intown skipping 3rd going to forth and keeps it under 40mph and he gets about 21-22mph with highway driving included at 60mph in 6th.
#25
Staging Lane
iTrader: (3)
Join Date: Jan 2006
Location: tupelo,ms
Posts: 75
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
mild cam, LT headers, LS2 intake, bigger injectors and 92 FAST TB, still get 26mpg unless i'm hammerin' on it...have never gotten less than 21 and change....i DO skip gears a lot, normal driving usually shift around 2k....
fuel shutoff....what's that ???
![Grin](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_grin.gif)
![Grin](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_grin.gif)
![Grin](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_grin.gif)
#26
TECH Apprentice
iTrader: (4)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Shift points are relative to throttle percent. More throttle = higher shift points.
Basically I'd say you want to shift right before the car stops accelerating in that gear. for example 1st gear at 1/2 throttle might be near 25 mph or so (sadly it's winter here and I can't remember the gearing on that car as I've got used to my dd that's also a stick)
Basically I'd say you want to shift right before the car stops accelerating in that gear. for example 1st gear at 1/2 throttle might be near 25 mph or so (sadly it's winter here and I can't remember the gearing on that car as I've got used to my dd that's also a stick)
#27
TECH Fanatic
iTrader: (2)
Join Date: Sep 2007
Location: Cairo, GA
Posts: 1,235
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
i usually shift around 2500 and try not to cruise too much lower than about 1400. my little rule of thumb for cruising with stock 3.42's is 3rd at 20mph, 4th at 30mph, 5th at 40mph, and 6th at 55mph.
#29
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I'll have to go against that there.
On the freeway in 6th gear at 110km/h (68 MPH) i get 11L/100km (21.4 MPG)
If i step it up to 125-130km/h i get around 8.5-9L/100km (26-28 MPG)
And if i cruise in 5th gear at 105km/h i get around the same as the 130km/h in 6th gear.
So my thoughts are they like to be around 2200rpm for good fuel consumption.
Any lower and they struggle.
Hook up a vaccume gauge and you'll see what i mean when it comes to the engine working harder in 6th gear
Actually might get a short vid next time im out on the freeway
On the freeway in 6th gear at 110km/h (68 MPH) i get 11L/100km (21.4 MPG)
If i step it up to 125-130km/h i get around 8.5-9L/100km (26-28 MPG)
And if i cruise in 5th gear at 105km/h i get around the same as the 130km/h in 6th gear.
So my thoughts are they like to be around 2200rpm for good fuel consumption.
Any lower and they struggle.
Hook up a vaccume gauge and you'll see what i mean when it comes to the engine working harder in 6th gear
Actually might get a short vid next time im out on the freeway
#30
TECH Senior Member
iTrader: (71)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I'll have to go against that there.
On the freeway in 6th gear at 110km/h (68 MPH) i get 11L/100km (21.4 MPG)
If i step it up to 125-130km/h i get around 8.5-9L/100km (26-28 MPG)
And if i cruise in 5th gear at 105km/h i get around the same as the 130km/h in 6th gear.
So my thoughts are they like to be around 2200rpm for good fuel consumption.
Any lower and they struggle.
Hook up a vaccume gauge and you'll see what i mean when it comes to the engine working harder in 6th gear
Actually might get a short vid next time im out on the freeway
On the freeway in 6th gear at 110km/h (68 MPH) i get 11L/100km (21.4 MPG)
If i step it up to 125-130km/h i get around 8.5-9L/100km (26-28 MPG)
And if i cruise in 5th gear at 105km/h i get around the same as the 130km/h in 6th gear.
So my thoughts are they like to be around 2200rpm for good fuel consumption.
Any lower and they struggle.
Hook up a vaccume gauge and you'll see what i mean when it comes to the engine working harder in 6th gear
Actually might get a short vid next time im out on the freeway
#32
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
And also why are guys over here claining to get batter fuel consumption with higher diff gears 3.73's and 3.9's.
Proofs in the pudding
I found that when on highway cruising fuel consumption dropped after putting in the 3.9's, this seem to be that the motor isnt loading up as much on some of those long hills as its cruising at a slightly higher rev range .
Last edited by mjr_350; 06-11-2009 at 02:27 AM.
#34
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
The newer VZ (04-06) has 3.73:1 diff ratio for the 6 speed and 3.07:1 for the auto
What final ratio do you have in your T56 LS1 powered cars
Last edited by mjr_350; 06-11-2009 at 08:52 AM.
#35
TECH Resident
Join Date: Jul 2006
Location: North Dallas
Posts: 828
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
You are not hurting a thing. You should know if you are lugging it, it will kind of surge or buck and just not feel right. Now cammed cars, on the other hand, don't like low RPMs. Mine does not like to cruise below 1600.
Here is a fuel economy question though. I took a road trip recently and got better mileage when my average speed was higher (80-85 vs. 70). Is the cam more efficient with a little more RPM? I actually measured 28.8 from Georgia to Louisiana! Oh, I have 3.73s too.
Here is a fuel economy question though. I took a road trip recently and got better mileage when my average speed was higher (80-85 vs. 70). Is the cam more efficient with a little more RPM? I actually measured 28.8 from Georgia to Louisiana! Oh, I have 3.73s too.
#36
LS1TECH & Trucks Sponsor
iTrader: (34)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Shifting or cruising THAT low might actually hurt your MPG, but it won't hurt your engine if you aren't under load. You will find that many people here get better mileage at 78-80mph than at 70mph. Lower RPM doesn't mean greater gas mileage if it's in an inefficient RPM range for the engine. Sometimes slightly higher RPM is a more efficient operating range of the engine and you will see better mileage at the higher rpm.
__________________
![](https://ls1tech.com/forums/signaturepics/sigpic3451_2.gif)
800-456-0211 / PM / Facebook
WHIPPLE Superchargers, Procharger, Magnuson, Powerbond Sale, HPTuners packages!, Trickflow, AFR, PRC, CHE Trunion upgrade, $100 7.400" pushrod set, Custom Cam of your choice
![](https://ls1tech.com/forums/signaturepics/sigpic3451_2.gif)
800-456-0211 / PM / Facebook
WHIPPLE Superchargers, Procharger, Magnuson, Powerbond Sale, HPTuners packages!, Trickflow, AFR, PRC, CHE Trunion upgrade, $100 7.400" pushrod set, Custom Cam of your choice
#38
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
y ai got this dudes back all my homies and me shift at 2000 or 2500 rpms saves u gas if u keep the rpms lower haha and try not to have the rpms at like 1300 thats a lil to low that berns more gas then at 2200 rpms
#39
12 Second Club
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
^^^ rpms have little to do with MPG, they count, just not as much as you would expect. Your MPG is determined by how much vacuum your pulling. If the throttle has to be wide open at 1200 RPM to maintain speed you will get crappy mileage. If the throttle can be almost closed at 2600 RPM for the same speed your MPG will go up.
You want to be in which ever gear allows you to use the least ammount of skinny pedal.
You want to be in which ever gear allows you to use the least ammount of skinny pedal.
#40
12 Second Club
iTrader: (12)
Join Date: Jul 2007
Location: NH
Posts: 806
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
35mph in 5th gear is usually fine as long as its down a hill or on a flat surface. When going up a hill either go faster or downshift. I typically shift anywhere between 1800 - 2500 rpm depending.