Too much gear? Not enough converter?

So after running my car this weekend with these new heads and cam it's obvious I've got some room to improve. Here's the setup:
D9TE block, two bolt mains, not filled.
4.390 bore
4.140 stroke, cast crank
Venolia 6.700 aluminum rods
Ross 14:1 pistons
Comp solid roller speced by Blake Cartwright
.786 .798
274 282 duration @.050
108 LSA
TFS raised port Mafia heads by Charlie Evans
Intake Exhaust(no pipe)
.100 70 52
.200 150 107
.300 238 150
.400 301 184
.500 344 215
.600 365 250
.700 376 262
.750 381 265
.800 385 267
Intake: new trick flow mafia intake.
1050 holley...for now.

The converter is a BTE 9" that only goes 4700 wide open on the brake. 9" rearend with a 5.00 gear. Seems to me that the converter should be more like 53-5500 and the gear a 4.30. Just need some opinions on where to start. I have fought sluggish 60 foots ever since I built this car and i thought all this new power would cure that. Apparently I've still got some work to do Would it be silly to go ahead and change the gear and have the converter loosened at the same time? Or do one at a time?

what tranny and tire height? 1/8th only or some 1/4?

Glide with a 29" tall tire, 1/8th mile only

With the kind of torque you are generating, use much less gear so you can run both 1/8 & 1/4.

i.e. I'm running 31" tires, 4.30 gear, glide and 9" 5500 converter. 1/8 mile passes are no issue while running 116-118mph and 1/4 mile runs = 7000-7100 rpm at 143-145mph.

3200#

Converter needs to be 5600-5800, I'd use a 4.57 or so gear.

Restalling a 9"converter to those numbers may make it not very aggressive up top.

D. Sea wrote:With the kind of torque you are generating, use much less gear so you can run both 1/8 & 1/4.

i.e. I'm running 31" tires, 4.30 gear, glide and 9" 5500 converter. 1/8 mile passes are no issue while running 116-118mph and 1/4 mile runs = 7000-7100 rpm at 143-145mph.

3200#

You run the same gear for both 1/8 and 1/4 mile?

richter69 wrote:Converter needs to be 5600-5800, I'd use a 4.57 or so gear.

Restalling a 9"converter to those numbers may make it not very aggressive up top.

So it wont pull hard in high gear? Please explain.

Is it still a good rule of thumb to shift a 1000rpm over the converters stall?

Race Ready Fabrications wrote:

D. Sea wrote:With the kind of torque you are generating, use much less gear so you can run both 1/8 & 1/4.

i.e. I'm running 31" tires, 4.30 gear, glide and 9" 5500 converter. 1/8 mile passes are no issue while running 116-118mph and 1/4 mile runs = 7000-7100 rpm at 143-145mph.

3200#

You run the same gear for both 1/8 and 1/4 mile?

Yep.... BBF Torque!

I shift into High gear about the 330' mark

A good rule of thumb is to stall 200 rpm below peak torque and shift 200 rpm above peak HP. Sometimes you will need to loosen the converter up if you have a heavy car or one with a lot of parasitic loss in the power train. Loose wil also be more consistant, to a point.

I agree w/Damon. A 4.30/4.57 would be best for 1/4 and 1/8. I can't believe you picked a 5.00 gear for a BBF. Its not a high winding small block that needs a big gear to keep the rpms high. You will be amazed what a gear change will do. Good Luck brother

we run a 5.00 in our high winding small block deal...............

bbf-falcon wrote:I agree w/Damon. A 4.30/4.57 would be best for 1/4 and 1/8. I can't believe you picked a 5.00 gear for a BBF. Its not a high winding small block that needs a big gear to keep the rpms high. You will be amazed what a gear change will do. Good Luck brother

The gear choice was more of just what I had laying around. I've got a set of 4.10's I can try, is that gonna be too much change?

It will be better than what you got imo. Use it until you get what you need.

Race Ready Fabrications wrote:

bbf-falcon wrote:I agree w/Damon. A 4.30/4.57 would be best for 1/4 and 1/8. I can't believe you picked a 5.00 gear for a BBF. Its not a high winding small block that needs a big gear to keep the rpms high. You will be amazed what a gear change will do. Good Luck brother

The gear choice was more of just what I had laying around. I've got a set of 4.10's I can try, is that gonna be too much change?

get the converter happy it will be fine.

richter69 wrote:we run a 5.00 in our high winding small block deal...............

we run a 3.50 in our high winding small block

Try the 4.10's You may be surprised how well it works with a 29" tire...

when you change to 4.10's your 60' will suffer,mph will be better,and may run same et.the heavier the car,the more important the converter will be for the 60'numbers,but dont get too hung up on 60'. what rpm you come off the brake?

cool40 wrote:when you change to 4.10's your 60' will suffer,mph will be better,and may run same et.the heavier the car,the more important the converter will be for the 60'numbers,but dont get too hung up on 60'. what rpm you come off the brake?

Right now I have the 3 step set at 4000. I think its gonna like the gear change alot. Because now with such a low gear it's hitting the tires so hard it spins after the initial hit no matter what I do. This has been a problem for 3 years now, it's just uglier now with all the extra ponies.

the gear will calm it down but i'd be looken at a 8"converter to make it 60'.you got a lot of et left in it when you get it worked out.

cool40 wrote:the gear will calm it down but i'd be looken at a 8"converter to make it 60'.you got a lot of et left in it when you get it worked out.

So what's the advantage of an 8" over a 9" converter?

More to it than a diameter, and I dont think an 8" is whats needed here. You need to talk with a converter expert like Lenny at UCC.

the converter you have wont act the same with 4.10's. you should figure out what gear you want then talk to Lenny,he's very good.i've tried a lot of converters and the more "stall" you put in a converter,be it 8"or 9"or even a 10",you'll notice it in the mph.it becomes a trade off,good 60",pissy mph and very little et.it's hard to get the best of both worlds but Lenny would be a good place to start.

cool40 wrote:the converter you have wont act the same with 4.10's. you should figure out what gear you want then talk to Lenny,he's very good.i've tried a lot of converters and the more "stall" you put in a converter,be it 8"or 9"or even a 10",you'll notice it in the mph.it becomes a trade off,good 60",pissy mph and very little et.it's hard to get the best of both worlds but Lenny would be a good place to start.

Ok cool, I'm just gonna stick this thing back together with the looser converter and 4.10's. She'll either go or blow. I'm already tired of screwing with this thing and it's only march.....

Race Ready Fabrications wrote:

cool40 wrote:the converter you have wont act the same with 4.10's. you should figure out what gear you want then talk to Lenny,he's very good.i've tried a lot of converters and the more "stall" you put in a converter,be it 8"or 9"or even a 10",you'll notice it in the mph.it becomes a trade off,good 60",pissy mph and very little et.it's hard to get the best of both worlds but Lenny would be a good place to start.

Ok cool, I'm just gonna stick this thing back together with the looser converter and 4.10's. She'll either go or blow. I'm already tired of screwing with this thing and it's only march.....

your just gettn started! converter issues are a real PIA.do give Lenny a try on it if you buy another one.he's up on the BBF torque.it'll come together

I'm good at swapin gears...............converter removals will be much easier now..............I never get tired of messin with it................its half the fun.