Shift light, tach, by ear, rev limiter; what's your choice

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Rev limiter and tach marked 100rpm lower that Rev limiter. Of course shift by ear would be learned very quickly but would not be as consistent as a tach.
 
light for me. You get to focus where you're going and only need to anticipate the flash to be consistent.
 
Shift by tach, has a shift light in it I think, but I don't use it. Rev limiter chip in the 6AL. Love my VDO replay (not recall) tach. Poor mans data logger. Shows rpm in the burnout, launch rpm, and all shift points, and finish line rpm. Come to think of it, I think it has multiple shift light rpms too.
 
So I usually hang out at N&P but was cruising along here and saw this thread. I am very lucky to have a neighbor who has a nitro funny car, got to join the team, we are all green.He has driven top alcohol before but never nitro. Have not made a race yet, trying to get the motor to cooperate ,she is having nothing to do with us yet. Man it is nothing like being around a nitro motor, the smell, the burning of the eyes, and of course it's loud as hell. We are going to do funny car chaos series, to hell with NHRA,chaos more relaxed and fun. Just wanted to chime in guys,:confederateflag: thank you:usflag::usflag::thumbsup::thumbsup:
 
Have the 6AL rev limiter set at 6K as my current cam is starting to tappet off. Going by ear and feel now, but I’ve been known to bound the rev limiter a few times and flat foot shift it through the gears.

Cars should have 3 peddles… :poke:
 
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Shift light!! Let me say that when I raced my mid-12 sec 69 Charger, it was always a tach. No issues, easy peasy...the car was just a gentleman going down the track. Set the tach red arrow at 6200 and shift it there.

Then 30 years later, I built the avatar 408 Demon. I thought I would shift by the tach in it too. OOPS...big mistake. First, the car leaves pretty hard, MUCH harder than the Charger and its 4260# of girth ever did. 1.51 60' was its best last year. Second, the TC stalls right at 5000 rpm so a shift is due really quickly after leaving. Need to find the best shift point but it's somewhere in the 5900-6300 range. Foot brake car so you just stanbed the gas and get thrown back, the front end is up. and you cannot be looking at a tach!! You have to have the light to tell you when to shift. I laughed at myself the first time out...there was NO WAY to look at the tach. The shift light was ordered and installed before the next weekend when we took the car to the track again. The shift light made it very easy to know when to smack the Cheetah shifter.

Now there are LOTS of people with cars way faster than mine on here, let's hear some more from them!
 
I never considered myself fast enough at mid 11s to justify a high dollar rev limiter, so I just used a big autometer tach. Had a manual valve body, so it shifted RIGHT when I pulled it.
 
I shift by feel. If you know your engine you will feel it get to peak by the way the car is moving out. Can't hear anything with another car next door at full song.

If I rev it too far the window switch turns off the nitrous. 1st sign to shift. If I am still on vacation it hits the limiter. 2nd sign to shift. By now we are losing and the rest is arbitrary.
 
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I'm also a shift light guy. Too much going on to watch a tach so that bright yellow light is the key
 
When the tack needle is at high noon it's time for me to shift.
 
So, next question. If you use a light, where do you set it? Assume you want the shift at 6000 (for the sake of argument), and the shift ACTUALLY happens 300 rpm after the lever is moved (auto only).
I used the tach in my nine second car, but it was a glide car, so the shift wasn't almost instantaneous off the line. My 11 sec 727 car needed the 1-2 shift quite a bit sooner....
As a spectator, at night at the drags, I see shift lights on for longer than I would like, in some cars.
 
So, next question. If you use a light, where do you set it? Assume you want the shift at 6000 (for the sake of argument), and the shift ACTUALLY happens 300 rpm after the lever is moved (auto only).
I used the tach in my nine second car, but it was a glide car, so the shift wasn't almost instantaneous off the line. My 11 sec 727 car needed the 1-2 shift quite a bit sooner....
As a spectator, at night at the drags, I see shift lights on for longer than I would like, in some cars.

I see that a lot in nitrous cars. I think some folks set the limiter n/a and spraying the car seems to extend the shift point rpm. I turn my beater up from a 6200 to 6700 otherwise I blow through the window switch deactivation rpm. With spray the engine accelerates quicker than running it n/a, however the driver stays the same (on vacation).
 
Tach. 273 HP, Isky E-4 solid lifter cam, single Commando exhaust, 833 O/D, 64-65 Hurst A Body shifter and linkage, power shift, 3.91 Power Lok sure grip.
 
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So, next question. If you use a light, where do you set it? Assume you want the shift at 6000 (for the sake of argument), and the shift ACTUALLY happens 300 rpm after the lever is moved (auto only).
I used the tach in my nine second car, but it was a glide car, so the shift wasn't almost instantaneous off the line. My 11 sec 727 car needed the 1-2 shift quite a bit sooner....
As a spectator, at night at the drags, I see shift lights on for longer than I would like, in some cars.


Exactly. You have to set the light at an rpm to start and then test. You can’t anticipate the light like you can watch the tach needle. So there is a big delay from the time the light comes on until the driver throws the lever. There is then a delay from when the lever is thrown and the transmission actually shifts.

There are far too many variables to say if you want to shift at 7000 you set the light at 6800 or some other number.

I know guys who have their lights come on 700 rpm before they want to shift.
 
Exactly. You have to set the light at an rpm to start and then test. You can’t anticipate the light like you can watch the tach needle. So there is a big delay from the time the light comes on until the driver throws the lever. There is then a delay from when the lever is thrown and the transmission actually shifts.

There are far too many variables to say if you want to shift at 7000 you set the light at 6800 or some other number.

I know guys who have their lights come on 700 rpm before they want to shift.
I use 450 under desired point. But I am old and slow!
 
So, next question. If you use a light, where do you set it? Assume you want the shift at 6000 (for the sake of argument), and the shift ACTUALLY happens 300 rpm after the lever is moved (auto only).
I used the tach in my nine second car, but it was a glide car, so the shift wasn't almost instantaneous off the line. My 11 sec 727 car needed the 1-2 shift quite a bit sooner....
As a spectator, at night at the drags, I see shift lights on for longer than I would like, in some cars.
I have mine set at 450 under target.
 
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