S/G Launch RPM
 

I am finishing up re-doing a 27 Roadster I bought turn key in the fall. This is my first drag car to have a Trans-Brake and will be my first car to run on a pro tree. I was wondering if anyone could share what they are setting the launch rpm at on their cars to give me an idea were to start with mine. Hoping to license the first weekend in May! 509 BBC backed by a ATI ProGlide, Dana 60 4.11 gears. Thank you all in advance, this will be a huge learning curve coming from my footbrake 11 second nova.

Re: S/G Launch RPM
 

5000 is a decent place to start. First of all you need it to be high enough to cut a light, then you can play with it up or down according to what the car seems to like.

Re: S/G Launch RPM
 

Lenny, that seems a touch high to me. Given its a big block roadster and likely pretty lite, I'd say it won't take much. I try to keep my stuff as calm off the starting line as possible to mitigate the risk of looping the tire or darting one way or another. I have mine set to 4200, but I have quite a bit more gear than this guy. It might take 5k to get it to move with a 4.11 gear, but I'd start low and work my way up if I had to.

I've got mine set up where I have just enough bulb to run .005-.010 delay everywhere I go. Prints 60ft tickets and never gives me the weenie, at least off the starting line.

Re: S/G Launch RPM
 

Thank you both for the tips! The car is supposed to weigh 2300 with me in it. Have not fully finished it to get the scales out yet. I think I will meet you both in the middle and start around 4500. I do truly appreciate you guys taking the time to give me advice!

Re: S/G Launch RPM
 

That seems reasonable. Especially with getting used to a new car that is much different than you are accustomed to, starting low is probably a good choice. You can always bring it up if you need to.

Good luck with it!

I see you're a D5 guy; maybe I'll see you out on the trail this year. I should be at all of them.

Re: S/G Launch RPM
 

I leave between 4500-4800. 2140 lbs. I carry .030-.040 in delay. Good luck!

Re: S/G Launch RPM
 

Lenny- I plan to license at BIR the first or second weekend of May then be at Tri State for the double National Open if all goes well!

Re: S/G Launch RPM
 

I may be at that second BIR weekend, but I'm always slow to get my stuff ready and get started.

Grove Creek for Memorial weekend should be happening, then Tri-State for the first divisional event.

Re: S/G Launch RPM
 

It's crazy that D2 will have had 4 divisionals before y'all have your first. This spring has been an absolute marathon between 4 divs and 2 nats, plus outs if you wanted to go to La.

Re: S/G Launch RPM
 

Same here in D7. Well kinda 3 nationals and 4 Diisionals for those that chase

Re: S/G Launch RPM
 

I leave at 5,000. But then again, I have 1014 Ib-Ft. (Foot-pounds of torque).

So, the question you ask yourself:

Is it better to have more torque or horsepower?
Well, if you just want to go fast and hit 140 mph, then horsepower would be more effective for you. However, if you want a strong car that can pull boulders and take off quickly, a high torque might be more important to you. In short, torque makes your vehicle quick. Horsepower makes it fast.

Re: S/G Launch RPM
 

I found in my 27 Roadster that it depends on HP and converter stall.. I was running a 565 with 1030 HP, and the stall is 6500 RPM.. I started at 5000 RPM, and moved to 5300 RPM to help with the tree.. I'm now running a 540 with 970 HP, and the stall is 6400 in OK weather.. still leaving at 5300, and having no problems with the tree.. I weigh in at around 2150 lbs.. 5000 would be a good starting point, and see how the car reacts.. with good power, these 27 Roadsters can be a weeeeeee bit violent, requiring adjustments..