Speedometer delayed......
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Joined: Dec 2010
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From: Maricopa, AZ
Speedometer delayed...... So today I was racing a C5 ZO6, no vids sorry, and noticed my speedometer was really really slow.
I know my Tach shows off, I shift at 7K on the dash but that's about 6300 actual to the engine (someone really needs to make a re-calibrated tach printout to go over the IP cluster).
But every time I shifted it was further and further off. I have verified the speedometer reads about 3% lower than my actual speed when cruising, and during normal driving there is no delay. But when I'm gunning it, it is WAAY off.
At the track when I cross the 1/4 traps my speedo would read 98-99mph, but my slip would read 107-108 (high DA's dammit).
So today while racing the Vette I noticed my speedo meter from 3rd to 4th showed about 100-101 when my rpms were right at 6800 on the tach. But, third tops out at 110 at 6300 rpms. Then at 4th to 5th it showed only about 115-120, same shift point (I only had time to glance). But, 4th tops out at 143 at 6300 rpms.
I know I was going much faster than my speedometer showed because when I grabbed 5th, I was easily 10 lengths ahead. And he was racing, he got the jump both times. And both times it was the same thing, speedo reading really slow, and Vette behind by 10 lengths at the end of 4th.
Anyone else experience this? How do I fix this?
Even my Data logs show me shifting from 1st to 2nd at about 51mph (1st tops at 53.81 at 6300 rpms), but my speedometer shows 45 when I shift.
This only happens at full throttle. Is it normal to be delayed? See sig for mods.
I know my Tach shows off, I shift at 7K on the dash but that's about 6300 actual to the engine (someone really needs to make a re-calibrated tach printout to go over the IP cluster).
But every time I shifted it was further and further off. I have verified the speedometer reads about 3% lower than my actual speed when cruising, and during normal driving there is no delay. But when I'm gunning it, it is WAAY off.
At the track when I cross the 1/4 traps my speedo would read 98-99mph, but my slip would read 107-108 (high DA's dammit).
So today while racing the Vette I noticed my speedo meter from 3rd to 4th showed about 100-101 when my rpms were right at 6800 on the tach. But, third tops out at 110 at 6300 rpms. Then at 4th to 5th it showed only about 115-120, same shift point (I only had time to glance). But, 4th tops out at 143 at 6300 rpms.
I know I was going much faster than my speedometer showed because when I grabbed 5th, I was easily 10 lengths ahead. And he was racing, he got the jump both times. And both times it was the same thing, speedo reading really slow, and Vette behind by 10 lengths at the end of 4th.
Anyone else experience this? How do I fix this?
Even my Data logs show me shifting from 1st to 2nd at about 51mph (1st tops at 53.81 at 6300 rpms), but my speedometer shows 45 when I shift.
This only happens at full throttle. Is it normal to be delayed? See sig for mods.
My stock 96 has a slow speedo and a tach that reads about 300 rpm high according to a datalogger. I thought it was just kind of the norm for these cars.
It's funny because the speedometer is pretty much perfect on my Z28, but the tach lags way behind in the lower gears.
It's funny because the speedometer is pretty much perfect on my Z28, but the tach lags way behind in the lower gears.
Thread Starter
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Joined: Dec 2010
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From: Maricopa, AZ
I'm gonna try removing the cluster and cleaning it out real good. Maybe it's just dirty and causing the needle to drag and reducing it's ability to accelerate as fast as the car is.....
Thread Starter
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Joined: Dec 2010
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From: Maricopa, AZ
Huh.
Well, I tried to clean it out. And while it was a little dusty it made no difference on the MPH delay. But, I was able to re-clock my Fuel and Tach needles. Now at half tank it reads half tank and at idle it reads 850 instead of 1100. So all is not a waste.
I guess I'll just deal with it.
Well, I tried to clean it out. And while it was a little dusty it made no difference on the MPH delay. But, I was able to re-clock my Fuel and Tach needles. Now at half tank it reads half tank and at idle it reads 850 instead of 1100. So all is not a waste.
I guess I'll just deal with it.
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I'd say thats maybe even more important than the speedo! Nothing more annoying than the difference between my dash tach and my Autometer ~400rpm. That and running out of fuel @ 1/4 tank
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Well, I tried to clean it out. And while it was a little dusty it made no difference on the MPH delay. But, I was able to re-clock my Fuel and Tach needles. Now at half tank it reads half tank and at idle it reads 850 instead of 1100. So all is not a waste.
I guess I'll just deal with it.
Well, I tried to clean it out. And while it was a little dusty it made no difference on the MPH delay. But, I was able to re-clock my Fuel and Tach needles. Now at half tank it reads half tank and at idle it reads 850 instead of 1100. So all is not a waste.
I guess I'll just deal with it.
So now that we have that situation cleared up!
Lets do something to make these fuel guages more acurate. At least on mine. If I add 2 gallons of gas from empty it reads a little less then half a tank. I find that kind of weired but I always thought it was a f-body thing.
Lets do something to make these fuel guages more acurate. At least on mine. If I add 2 gallons of gas from empty it reads a little less then half a tank. I find that kind of weired but I always thought it was a f-body thing.
Thread Starter
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Joined: Dec 2010
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From: Maricopa, AZ
So now that we have that situation cleared up!
Lets do something to make these fuel guages more acurate. At least on mine. If I add 2 gallons of gas from empty it reads a little less then half a tank. I find that kind of weired but I always thought it was a f-body thing.
Lets do something to make these fuel guages more acurate. At least on mine. If I add 2 gallons of gas from empty it reads a little less then half a tank. I find that kind of weired but I always thought it was a f-body thing.
I'm gonna run through a couple tanks as is and see how the needle compares to actual fuel refills.
Thread Starter
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Joined: Dec 2010
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From: Maricopa, AZ
Well, I already knew the tach was off. Mine was off by 250 at idle and about 700 at redline. Now, it wont be so bad. The fuel gauge should be more accurate now but I'll have to get used to the new needle position in relation to actual fuel left in the tank. But, I didn't expect the speedometer to lag soo much during hard acceleration. In normal driving there's not an issue. But it does explain why it took me so long to get to 110mph...
Thread Starter
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Joined: Dec 2010
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From: Maricopa, AZ
Well, I was able to have my better half read out my data log and GPS while I was driving and reading the dash. The Data log and Dash match, tit for tat at low throttle and cruising. Still dialing in the GPS.
At full throttle or hard acceleration the speedometer doesn't catch up until I let off. Weird.
At full throttle or hard acceleration the speedometer doesn't catch up until I let off. Weird.
Well, I was able to have my better half read out my data log and GPS while I was driving and reading the dash. The Data log and Dash match, tit for tat at low throttle and cruising. Still dialing in the GPS.
At full throttle or hard acceleration the speedometer doesn't catch up until I let off. Weird.
At full throttle or hard acceleration the speedometer doesn't catch up until I let off. Weird.
Thread Starter
TECH Addict
Joined: Dec 2010
Posts: 2,610
Likes: 4
From: Maricopa, AZ
I doubt it because it keeps up fine in my data logs. 1-2 shifts happen at 51-53 mph in my data log. But my speedo says 45ish. When my wife was reading the data log and GPS for me I was driving nice. I never throttled it.
She doesn't like it when I drive like an idiot, she broke her back a while ago so it hurts her when I drive aggressively. So I avoid it with her in the car. My kids though, they LOVE it!
Maybe I should pull my IP cluster and replace it with a tablet screen and Tuner Pro RT Dash mode........
She doesn't like it when I drive like an idiot, she broke her back a while ago so it hurts her when I drive aggressively. So I avoid it with her in the car. My kids though, they LOVE it!
Maybe I should pull my IP cluster and replace it with a tablet screen and Tuner Pro RT Dash mode........
