Looking for pros and cons of high gear only vs quick shift from low to high....4.60 dragster

What's the "go to" high gear-only trans brake valve body......

Pros of leaving in high is the high gear clutches are locked up when the car leaves. Shifting early the transmission is trying to shift when the converter is at max torque multiplication.

Cons are the cost of a high gear brake.

If I may ask what are you trying to achieve by leaving in high or shifting early?

!st gear went out this weekend in Vegas so I had to footbrake high gear only. I did shyt foot braking but I sure liked the smooth leave of high gear only.....lost .6 in et and a fat tenth in 60" but et repeated pretty well....I've seen people rave about high gear only consistency, and getting opinions/advice...

If you run a high gear trans brake make your you have the delay box safety lock out turned on and set for atleast a minute so you don't accidently hit the TB button going down the track and lock up the trans, I promise you it wont end well. I had a high gear TB once in my dragster and accidently hit the button going thru the pits and the car stopped instantly and almost thru me out of the seat

What you experienced are some of the pros of high.

When the rounds start going quick I need to put a modified leaf blower on the converter and trans pan.

Id honestly find some that can build you a cast iron high gear brake. If you can't find someone FTI sells aluminum high/lo brakes. I was struggling with inconsistent reaction times when I first got them. I made a few modifications and they got better I honestly have no idea what fixed them but I do it to them all now.

quote:

Originally posted by Big Steve:
If you run a high gear trans brake make your you have the safety lock out turned on and set for atleast a minute so you don't accidently hit the TB button going down the track and lock up the trans, I promise you it wont end well. I had a high gear TB once in my dragster and accidently hit the button going thru the pits and the car stopped instantly and almost thru me out of the seat

What he said. I use two buttons in series or use SLE the output and relay to send power or ground to the TB button.

Since heat is an issue is there someone that makes a high-gear TB in cast iron?

Dave I am sure most any builder like FTI or Abruzzi will convert yours or sell you a HI/LOW valve body.

The heat issue is with the converter because its going to be loose and slip down low so your going to need some way to cool it and the trans down between runs

One fella on site runs hi gear only lots. I think it is Curtis not sure maybe he will chime in.

I had Marco build me a new glide this year with 1.65 low gear and hi gear VB. He only builds the hi gear VB from cast VB's. He will convert yours as well. I'm a 2450lb door car and I double most races and heat isn't really an issue until getting late in the rounds. A normal summer run 2500-3000DA would be 5.03-5.08 @ 137 in low gear and in hi it runs 5.45-5.50 @ 134.5-135. Car is crazy consistent but I am struggling with reaction time inconsistency from time to time. Don't know if it's me or the car. I'm assuming it's me but I've talked to others that have tried it and also struggled with consistent reaction time.
It is a good tool to make people scratch their heads as they try and figure out how a 5.50 car drove around their 5.30 car.

Wouldn't it help with reaction times if you left in low the shift to hi at say .500?

With the TD I never pulled any timing before .300 for the same reason, I didn't want the timing to affect the RT

If this was responding to me it would certainly make the reaction quicker but not sure about more consistent. I'm bracket racing with a delay box so not really a concern on quickness. With that said I take .020-.025 out of the delay box when running high gear.

quote:

Originally posted by Big Steve:
Wouldn't it help with reaction times if you left in low the shift to hi at say .500?

With the TD I never pulled any timing before .300 for the same reason, I didn't want the timing to affect the RT

I have done a lot of high gear racing. My application is different though because I am a footfeeder. One thing I can tell you is that my car is stupid consistent that way. Shifting early into high to kill ET has never been even as consistent as leaving in low on a normal pass.

I have to up my leave rpm from 2500-2700 in low to 3200-3500 in high to hit the tree the same. Again this is off the foot.

Heat can be a problem if you are doubled. I carry a carpet drying fan to blow under the car when I'm running high only.

I can tell you that running high only is fun because it looks different to the guys you're racing and it can cause mistakes on their part.

What kind of trans temps are you getting in high gear only?

quote:

Originally posted by SP 124X:
What you experienced are some of the pros of high.

When the rounds start going quick I need to put a modified leaf blower on the converter and trans pan.

Id honestly find some that can build you a cast iron high gear brake. If you can't find someone FTI sells aluminum high/lo brakes. I was struggling with inconsistent reaction times when I first got them. I made a few modifications and they got better I honestly have no idea what fixed them but I do it to them all now.

Some are using leaf blowers to cool converter. I prefer to set it up to handle heat as much as possible on its own.

I have not seen any of these in a long time but maybe they need to make a come back. I think it was Shogun? That made a fan that fits between converter and flex plate and I think those things moved a lot of air when you needed it most. Any thoughts on them? Does anyone still use them?

On last car I built I put a large transmission cooler and a Derale Transmission thermostat that returns most of fluid back to transmission until it reaches temp and then it starts directing it through the cooler. Then I got opportunity to drive another car and really do not have many laps on the car to tell you how well it works.
You can also use a thermostat on the transmission cooler fan that turns on at desired temp.

quote:

Originally posted by TomR:
What kind of trans temps are you getting in high gear only?

If I'm doubled in the summer I can see 230° or more at the end of a pass. Obviously round call times will vary how bad it gets.

Some may not have as much of a problem depending on how good their cooler set up is. The heavier the car the worse it can be, the faster the car the same. I'm only a 6.0-6.10 car running high gear and 1985lbs.

Speaking too the temp issues I have run dual coolers in series for years keeps trans at about 160 atleast till semi finals has worked in my old car-2300lbs. and in new ride at 2900lbs.

Heck, the way I left the starting line and with everything else I screwed up I might have run high gear only.

Dave, you coming to Bakersfield in a week?

F I hope so Mike.....I hurt my transmission in the dragster over the weekend and having some trouble finding someone to fix it.....it would be SOOOO nice to race there after many years....

BTW, do you know what they're running? Brackets, indexs, pro or full tree? 1/4 0r 1/8 mile? A flyer maybe?

Thanks