Trans gear and other recommendations needed.

I recently purchased a top dragster and am going through the “discovery” phase right now. The owner was the driver only and doesn’t know anything about the car. The crew chief passed away so I have absolutely no information on the setup. I’m tearing into it now, starting with a clean slate so to speak. Th idea is to do it right and get it setup properly.

I happen to be heading to Utah tomorrow so I decided to bring the B&J 2-speed trans with me and have Steve put a new trans gear in it. It currently has a crazy high 2.10+ gear! I talked to Steve and he recommended a 1.55 gear but I would love to hear others thoughts.

Here are the basics of the car…

300” Top Dragster. Don’t know weight but est. 2200 – 2400 lbs.

464ci BAE Fathead 5 Hemi. PSI – D rotor. MSD 44. Have not torn into the motor yet so I do not know anything about cam, compression, bore/stroke, etc… I will be changing out rods, pistons, bearings, cam/lifters, springs, etc and can put in whatever compression and cam which makes sense. Fuel system needs to be setup as well so I’ll be sending it out to Randy A. at some point.

Quick drive w/Chance converter (converter will go to Chance once I finalize the motor/driveline specs)

Strange top loader – 4.29 gear. I am open to change this but would prefer to try to make it work (if it makes sense.)

B&J 2-speed, 2.10 ish gear currently.

Tire are currently 34.5x17x16 Goodyear’s but they are old and must be replaced. Recommendations are welcome?

There was no computer or timing controls on the car. So I have a RPM Performance logger and a Grid coming.

Operational Objectives:
1. Low maintenance/high reliability and consistency.
2. Wide tuning window. Not swinging for the fences, just looking for a combination that doesn't run on the edge.
3. Able to safely make the HP to run the number (~6.10 ET) at any density alt.


At this point, any recommendations on trans gear, rear end gear and tire size would be much appreciated. Also, any recommendations of reputable nearby engine builders would be appreciated. I am up near Reno, NV.

Thanks to Will for creating such a great forum and all of you who take the time helping others ~!


-Bill

 

There’s nothing wrong with going back with the Goodyears. Some folks like the Hoosier and some top dragster guys like the Mickey “big bubba”. The 4.30’s and 1.55 is in the ball park, that sure will tame it down and make it more consistent. Set your engine combo and figure out a rough weight before you call Marty. The more accurate info you give him, the closer he will get your converter. Any idea on what overdrive you have or what overdrive you are allowed? Are you planning on running any sort of fuel management? You should invest in a weather station and some software or your choice to compensate for the weather. There are a couple of options available.

Just out of curiosity why did you chose to go with the grid and RPM Logger?

 

Thanks for the input. Good to know that Goodyears are good to go.

Steve tore apart the B&J and found out that it is actually a 1.50 gear. Guess I need to figure out how to measure shaft turns, lol. I'm going to stick with it for now and see how it goes.

Good advice, I'll borrow some scales and get a weight for Marty before I send it back.

There is no limit on OD in NHRA Top Dragster. I'm not sure what OD I'm going to target. Probably shoot for higher OD (110 - 115). My theory is that if I get the fuel system base lined at for higher OD, I can remove OD if the pump falls off. Then I can just take out power when/where I need it with timing management.

I wanted to stay away from fuel management and eliminate the risk of a malfunction of a fuel system component.

I like the RPM Performance stuff because it does what I need it to do for a lot cheaper. I'm also impressed with Randy's customer service. I also like supporting the little guys when it makes sense.

As far as a grid goes, it seems to have everything I need. I'm an ex Mallory electrical engineer so I nerd out a bit on ignition management also

Thanks again for your help ~!

 

Thanks Will, I'm in Hawaii but will call you when I get back next week.

Thanks for the correction on the O.D. limit too