Tach Lag

[Dominic]

Something which was brought up to me a while back by Camaro_Zach and Magnus is the infamous late model tach lag.

You rev, and then look down to watch it still going up after the engine is back at idle... thats seriously how bad it is, and I think its GM's infinite wisdom trying to make the tach "smooth" instead of "responsive"

I know the 97's didnt do it, and nothing before them, so its a 98+ or 99+ thing. All the gauge clusters which have a coolant scale that starts at 160F are unaffected, anything else has tach lag.

Im not sure how to get rid of it, other than put in a shift light (this is assuming the PCM isn't lagging and its just my cluster). Anyone got any fix ideas for it? I've actually *gasp* thought about telling GM and asking.

[camaro_speedemon]

An aftermarket tach should fix the problem. AFAIK most cars have this, mabye not as bad, but I believe it can easily be fixed by a good aftermarket tack like autometer. My friend just got a digital one, it looks like a shift light, and has yellow LEDs that come on for a set RPM, but the center of it has Red LEDs that give the RPMs, it's pretty cool.

[WickEdSix9838]

i think its 99+ cars, my 98 isnt bad other than the fact that it reads 400 RPM too high

[Magnus]

its a 98+ problem. I tried a 98 cluster and it was horrible. My 97 V6 cluster in my LS1 with a tach signal converter is INSTANT.. god I love a fast tach..

No way to fix the 98+ tachs. You need to use aftermarket.

[navyblue2000]

this is all odd, as the 97+'s ALL got an updated interior.

I always believed it had something to do with the 99+'s electronic throttle causing a crappy tachomoeter.
maybe mine's retarded. maybe i do have a 5900 rev limiter :(

[Lord_Verminaard]

That blows. Do the 98+ Z-28 clusters do it as well? That really bothers me, especially since I still have stock exhaust and it's so damn quiet I can never tell where it is in the RPM's. If the 98+ Z-28 clusters with a signal converter fix it, I'd rather do that instead of adding an aftermarket tach.

Brendan
2000 Camaro L36 M49

[navyblue2000]

my brother's 98 Z28 has no tach lag at all.

[Dominic]

Maybe I should buy a 97 cluster and use it to fix the lag?

[Lord_Verminaard]

Will the 97 clusters work and fit with a 98+ car?

Brendan
2000 L36 M49

[Distephano]

Thats really strange. So its just a problem with the electroics that causes the lag?

How much of a lag is it?

I'm glad my '97 doesn't do it [img]smile.gif[/img]

[Magnus]

Its a 98+ problem as I previouly stated.

For those of you who think there is no lag, you aren't familiar with the 97 and prior tachs. They are INSTANT and responsive and update QUICKLY.. there is ZERO delay.

its an electronics problem that really cant be fixed.

97 cluster won't work in 98+ cars.

[navyblue2000]

is there any reason it won't?

97's share the same interior completely, same engine, most the same PCM stuff too...

[Magnus]

fuel gauges work differnetly. on 99+ coolant gauges work differently.

[Dominic]

THanks magnus, I wasnt sure because they are the same SHAPE at least. The coolant gauge range is different yeah.

[57s98Camaro]

Yeah, my tach lags bad. I thought it was just my clutch, but I'll see it like stick at 2K for half a second then jump up 400-500RPM.

Eh, I guess I can live with it. Sucks when I'm trying to run it up and tap redline before shifting though.