- Thread starter
- #61
Oh and I was using a GPS speedo app on my iPhone. Have not calibrated the Dakota Digital instrument cluster yet. It said I was going 20mph. 
ARCHIVE 5.3 Vortec FJ40 build - CruiserCrap's Delivery Truck
- Thread starter mmw68
- Start date
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Interesting. That is with a 4 speed? Good numbers there.
What rear axle ratio do you have?
Thanks for the input.
What rear axle ratio do you have?
Thanks for the input.
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- #63
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- #65
I'll be happy to video it... And why would I make this up? Unless the direct fee from the ecu is wrong.
If you are geared to run 65 at 1300 rpm, if you rev to 5500 rpm in high gear, you should be doing 275 mph according to the math. Are you really geared that tall?
- Thread starter
- #67
275 MPH in a FJ40... I would like to see that!
I am sticking a 5.3 in a FJ40 with a four speed and have already been playing with the rpm calculators. They say the rpm should be at least twice what you listed.
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Based on your numbers
1300 rpm = 65 mph
2600 rpm = 130 mph
3900 rpm = 195 mph
5200 rpm = 260 mph
5500 rpm = 275 mph
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- #70
I'll reset the Dakota digital and take another reading .
- Thread starter
- #71
What rear end and tire size Are you using?
What are the odds you were driving 35 mph?
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- #74
I have 4:11, and 33 inch tires, I just went out and adjusted the electronic speedo - it's now dead on with my GPS.
I will go for another drive and make sure the Tach is also set correctly.
I will go for another drive and make sure the Tach is also set correctly.
The GM PCM puts out a 4 cylinder tach output. Your tach is likely reading half the rpm's. Switch the input on your tach to 4 cyl and it will be accurate. If you double your recorded numbers it comes out pretty close for the mathematically calculated figures.
- Thread starter
- #76
Watty - I think your correct, I spoke with the engine builder today, and he mentioned the same thing. I'll make that change and report back...
kling-on
Kool Arrow
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Looking good glad I could help
- Thread starter
- #78
@Wattsy and @Flipper1938 Thanks for the catch and on my RPM's I've reset the Dakota cluster to 4 cylinder tach output, and things look more normal now.
I was also able to adjust the speedo for 33 inch tires. There is a cool feature on the Dakota cluster that lets you adjust the speedo to match reading on a iphone GPS app . Once the instrument panel is in the adjustment mode, it shows your speed on the left LCD screen, and you hold down a button to move the reading up or down.
I was also able to adjust the speedo for 33 inch tires. There is a cool feature on the Dakota cluster that lets you adjust the speedo to match reading on a iphone GPS app . Once the instrument panel is in the adjustment mode, it shows your speed on the left LCD screen, and you hold down a button to move the reading up or down.
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- #79
This weekend I hacked into my garage opener remote - and added a pull knob on the dash to control the garage.
- Thread starter
- #80
Here is what I did:
I removed the button on the circuit board:
Then made a jumper using some red and green wires:
Then I hooked those red and green wires to a old school pull switch I had laying around, when you pull the switch - it's like pushing the button. I then shoved the remote up under the dash, and mounted the switch.
I removed the button on the circuit board:
Then made a jumper using some red and green wires:
Then I hooked those red and green wires to a old school pull switch I had laying around, when you pull the switch - it's like pushing the button. I then shoved the remote up under the dash, and mounted the switch.
