I bought my new gears and was wondering if you guys think that I'm going to lose alot of et in the 1/8 mile going from a 4:88 to a 4:10? I am currently running a 7.64 @ 94mph w/a traction limited 1.79 60 ft. I can only give it about half throttle for the first little bit or it spins badly. The reason I'm changing gear ratio is so that I can finish the 1/4 mile. I currently rev out at the 1000 ft mark. I can't wait to hit the track!!

Deano

I think you will improve your ET by going with a 4.10.
If you fine tune your launch, I would say that you might see an improvement in 60' times and ET with 3.73:1 gears.
Let us know how it works out.

i think your et will improve also because it will help on the launch,less tire spin .you really need to work on suppension some you shoud be 60 footing better than that if you are running slicks anyways

I have the near exact same situation with my car, I ran 94.6 in 7.6X with a 1.77 60ft. I had a 4.56 gear and had to let off just past the 1000ft mark, it went 11.7 in the quarter even after lifting. I have changed to 3.73s and will get back to the track friday night to see what the change is. I'm hoping for quicker.

I'm not running true slicks but I am running BFG drag radials, and the car only hooks if I'm very gentle with the pedal.

Kamero please let me know how your car runs this friday it will be very interesting to see! Good luck

Deano

It should pick up. Big Blocks don't need a lot of gear.

I have the same situation as Kamero68 i too just went from 4.56 to 3.73. I would really kike to know how it affects the track performance. so far i really like the 3.73 on street.

I'll let you know what happens friday night with the gears. I've got a new 950 carb that I want to try also, its replacing the 750 that I had on the small block that was in my car, but I'm not going to mess with the carb untill I make a few runs. I want to see what the gear change does with no other changes.

Rain is in the forecast, so I hope we dont get rained out. errrr

dirve it like you stole it kamero!
Eric B

OK, results are in. Made some runs tonight with the new 3.73 gears.

Old best with 4.56 and running out of gear....
60ft=====1.77
1/8 =====7.67
1/8 =====94.6 mph

1/4 =====11.79
1/4 =====113 mph

new best with 3.73s and crossing finish at 5700rpm
60ft=====1.67
1/8 =====7.36
1/8 =====95.99 mph

1/4 =====11.49
1/4 =====118.86 mph

other 2 passes, 11.66(first run) and 11.55(3rd run) and all runs were 118.xx mph

Shaved off a full .3 seconds, picked up 5 mph, dropped the 60ft .1 and drove the 40 miles to the track and back at 65mph instead of 52mph. I guess that shows a long stroke bbc would rather torque than rev.

Cant wait till next races, I'll have the 950 carb on by then. I cant help but feel the 750 carb on it now is way to small for a 505 bbc.

I hope your gear changes work as well for all you. good luck.

Scott
http://www2.hotboat.com/image_center/data/506/226IMAGE047-med.JPG

Wow Kamero i hope mine picks up like that! i was running 117 with the 4.56's so maybe i will break into the 120's. I cant wait to try.

A gear change will definately help. But, I feel you have other issues like suspension tuning if you can't currently hook on a 315/60 drag radial. That is a stinking HUGE tire.

With your weight & power, you should easily be able to dead hook on that large of a drag radial tire going to WOT immediately off the line. If you can't, then either your suspension needs tuning, or you need a better converter.

5mph, not bad... the HP950 should put you over 120mph.
then just work on the 60ft.

Yea Rafel, after I test and dial in the carb at the track next week, I'm going to start tuning on the suspension, and I'm still running those 28/12.5 ET streets I bought from you a couple of years ago. I dont know how much you used them, but I have put 3000 street miles and 38 track runs on them. So some new tires might help the 60ft too. My wife taped a couple of runs last weekend, and in slow mo you can tell the tires are spinning for the first couple of car lenghts.

Let us know how you car does Yellow68ss