Anyone else ever noticed when you pin it and let off the throttle, the speedometer will continue to go up for about half a second? I find if I pin it from like 40km/h in second gear, just enough to get to full boost and let off, the speedometer will still go up 15km/h after I've let off the throttle...

I don't think anything's broken, I think my car is just too fast for the speedo, lol.

 

Yup, it's been brought up a few times before, the tach and the speedo are slow...our cars are just too damn fast...lol. If I punch it it's a good few tenths of a second behind and it will keep rising after I left off the throttle.

 

I have had that problem with my SS/SC since I installed the 2.8, but I can let off the gas AND hit the brakes for a second before my speedometer starts to go down

 

I brought that subject up a few times now in different threads. It lags behind when accelerating or decelerating, up to 6-7 mph in some cases.

 

Ah, sorry, didn't even think to search...

It does make me wonder though...I always felt my 0-60 times were just a tad slow, so now I know I can attribute some of that to this.

 

It is ok. I used to wonder too.

 

what if the speedo is not off, have you ever thought that you are getting so much momentum and inertia built up that when you let off the car still is excelerating for that tenth of a second. That is what I think it is.

 

Not possible. You can't accelerate without an applied force. As soon as you take your foot off the pedal the car is slowing down due to wind drag and rolling resistance. No way in hell it is still accelerating.

 

its a time delay, the needle is in fact slow
the RPD on the other hand is much more instantaneous

 

RPD digital speedo FTW!

I;ve noticed that the RPD and analog speedo can be off by at least 4-6 mph at times. RPD says I'm at 60 when analog say I'm at 55!

 

Mine are spot-on. Do you mean when accelerating/decelerating? If so, then I can see that.

Well, technically as you're letting off the gas, there are fractions of a second where you are in the process of letting off the gas, no matter how fast you're doing it. The throttle plate is in the process of closing and the bpv vacuum line starts building vacuum until it bypasses the air charge. During that time, you are slowing your acceleration, but still accelerating nevertheless.

 

yup, when accelerating! When I'm cruising they're spot on, but accel/decel the digital speedo is more accurate!

 

My car was hitting 111-112 mph on the dyno at 6800 rpms but the speedo was saying 105-106 mph. When I do the calculation 111.4 mph is what I get a 6800 in third gear so it is indeed quite slow when accelerating.

 

your just travling back i time

 

LOL the car is too fast for the gauges!

 

that's funny!

 

Yeah my gauges are slow as well, I got the dashdaq and during acceleration it can read 5-6 mph off same with the tach

 

Yes, it bothers the HELL out of me. I HATE how slow the speedometer is, and a slow tach is un-excusable.

It's not due to the car continuing to accelerate after you get off the gas. If you want to prove it, do the test in reverse...come to a stop QUICKLY, and you'll see the speedometer climbing down even after you're at a dead stop. So stupid. I routinely let off the gas when the speedometer indicates 40, only to have it come to rest at like 47mph.