Can Anyone Tell Me What Rpm A 5 Spd Car Turns At 70 With 4.10 Gears ? Also How Much Can I Expect To Gain In The Quarter Going From 3.55 To 4.10 ?

 

I just had 4.10 gears installed last week. Previously (with 3:55 gears) my
car ran 2000 rpm's @ 70mph. Now it turns 2400 rpm's.

Great mod, no regrets.

 

Thanks, guess that's next.

 

4.10's rock; get them. No-brainer...

 

Yeah, I would think they would rock, but if you drive 100+ miles a day on the highway, how much more $$$ will you spend in a years time in additional fuel cost???

 

That's why they make Chevy's

 

Well, I don't think you will lose more than 2 mpg, but if fuel mileage is your concer , may I suggest some nice 2.73's?

 

or if you are going for some land speed records

 

I'm looking for my UDP's to balance out the 4.10's.....
I'm real happy with the gears.

 

I wonder if we could get a MPG at 80mph in 5th with 4.10s vs. 3.55. We do have a MPG meter on our vehicles. Not too scientific unless the same vehicle. But I am willing to post what MPG I get on level interstate at 80 MPG with my 3.55 gears.

Procedure: Get up to 80 mph. Reset average MPG and average Speed. Drive 20 miles. Try not to change lane, follow vehicles, level road, a/c off, radio off, lights off, full tank of gas, etc. FWIW, Sunday morning is perfect to repeat conditions like this.

 

3.55 Gears, 68 MPH, 5-spd, 93 Octane, UDPs, Racer Intake = 29 MPG
Combination of Hwy and City yields 22 MPG.

Same combination roaring down the highway gets about 22 MPG.

I can't see how 4.10s are going to kill any MPG unless you do a lot of high mileage 70+ MPH trips.

It's the 1/4 Mile launches that will kill your fuel consumption and tire life. This is the most cost ineffective part of 4.10s. If you're simply concerned with RPM, go ahead and pull the trigger on the swap.

 

I've only got 1500 miles on my car, but so far it is only showing to be getting 18.5 mpg . I hope that gets better with more miles. (07 gt 5spd 355 gears)

 

I still have to get to the track with the stock gears. With the 3:55's you can get through the quarter in 3rd, with the tune's raised redline, I get over 70mph out of 2nd. And the only way to get proper MPG is to measure/calculate it at fillups. I was coasting to a stop in 5th the other day, hit reset, and got 55mpg. If I had to drive the way required to get 23mpg out of my car, I would be in danger of falling asleep at the wheel.

 

I know this is a gear thread but without changing any driving habits I have gotten 2 more MPG since I installed the Spyder 1 piece driveshaft.

 

You will get better mileage. Mine got better after 5K miles. I did oil analysis the whole time and it finally was "broken in" after that period. Adding a tuner and underdrive pullies will give you about 5 miles per gallon. I put a C&L Racer on the wife's 06 GT Vert Auto and she went from 18 MPG to about 21.6 MPG. The manual is going to be much better on fuel and mine has UDPs on it as well.

You should expect 20 to 22 MPG when it is broken in and you drive "civil" on all Hwy. If you do the Intake, Tune, UDPs, DriveShaft and Electric Water Pump it seems you could theoretically touch 30 MPG.

Anyone hit 30 MPG?

 

I have 4:10's and they are awesome. However it all depends on your route to power...if going FI then you will be ok with 4:10's wouldn't suggest any lower.

If staying N/A might want to look at 4:30's or lower since we have a higher powerband starting around 3500 rpm, you can keep the car where it needs to be while going through the gears. Got a friend with 4:30's and all I can say is WOW...

just invest in some good wide rubber and you will like the result...

 

I have 3.31s and 18s". I think I cross the finish line in 1st.

 

LOL!!! That's how I felt when I traded in my 05 (3.55's) for my 07 (3.31's). I HATED that gear! Took me a couple of months of hating driving the 07 to finally break down and get 4.10's. Now I love it!!!! The ONLY downside is crossing the traps at the track in 4th instead of 3rd.

 

Can a Ford shop install FR 4.10's? Would my warranty still be normal with a 4.10 install?