Suggestion on New 3rd Member

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6

69Chrgr

Charger/Cuda
Joined
Jan 29, 2007
Messages
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Location
Midlothian, Texas
O.K., I have now less than a month to button everyting up and hand a Firebird his *** at the track. Will anyone give me a suggestion on picking a gear ratio for my new replacement 3rd member? Here is my current combo:

408 Magnum
Stock Eddy Heads
Speed Pro Forged Pistons
Square decked and cylinders honed with plates
Eagle Crank SIR Rods
10.5:1 compression?
Hughes Roller .555 Intake, .565 Exh., 242 and 246 @.050
Crane 1.6 Rockers
Milodon Windage Tray
MSD Ignition
Black Magic Electric Fan
M1 Single Plane
Quick Fuel 750 Q Series
March Underdrive Pulleys
Dynamic 9 1/2 converter, 3700 stall
998 with 2.74 first gear
Currently 3.91 Sure Grip, growling like hell and 235/60 BFG Drag radials that act like your driving on ice when you matt it.
Waiting on 275/60 M/T's to arrive.
What gear, and setup and from where to order?
Please help.
His car
87 Firebird, 350, Dart Heads, 750 Demon
His time so far in 1/8th which is what we'll run: 8.7 @ 83

Thanks Again!
 
I would go with a 4.56. I think with the 3.91 and no traction you should still run faster than an 8.70. My car has alot milder motor than yours just a 360 with mopar 292/508 cam, set of 587 heads with 2.02 1.60 valves and 4 speed. I am running a 3.55 gear right now, never had it to the track, but did race an 84 Camaro with a built 355, and he had 4.56 gears he runs consistant 8.50's. I beat him by about 1 car lenght in the 1/8th. Your car should be faster than mine.
 
Is it a street car or track only??...what car are we talking about,do you know how much it weights...
 
Street Strip. 68 Barracuda notchback, right around 3100 lbs. I presume. I went ahead and ordered a 3rd member w/powertraxx and 4.11's. Going from 26 inch diameter BFG's w/3.91's to 28 inch diameter M/T's w/4.11. Hope I don't lose too much gear. However right now it does nothing but spin the little BFG's and desperately need traction. I don't drive on the freeway as I live in a rural area. Just around town. Will trailer to 1/8th mile and 1/4 mile track.
 
69Chrgr said:
Street Strip. 68 Barracuda notchback, right around 3100 lbs. I presume. I went ahead and ordered a 3rd member w/powertraxx and 4.11's. Going from 26 inch diameter BFG's w/3.91's to 28 inch diameter M/T's w/4.11. Hope I don't lose too much gear. However right now it does nothing but spin the little BFG's and desperately need traction. I don't drive on the freeway as I live in a rural area. Just around town. Will trailer to 1/8th mile and 1/4 mile track.
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Sounds good i think you'll do well with the 4.11's who's building it for you?..as far as traction throw a set of drag shocks on the car,i'm running the Summit brand on my duster they're cheap price wise,and do help my car 60's in the 1.40's with nothing more then the shocks,h.d. leaf springs and a pinion snubber..as for the m/ts you'll need to experiment with them to see what pressure your car likes..mine hooks great at 15 psi's..
 
Thanks 340. I have competition engineering drag shocks all the way around, pinion snubber and s/s springs. Could you tell me a little about your combo and latest performance values at the track?
 
340srule said:
Sounds good i think you'll do well with the 4.11's who's building it for you?..as far as traction throw a set of drag shocks on the car,i'm running the Summit brand on my duster they're cheap price wise,and do help my car 60's in the 1.40's with nothing more then the shocks,h.d. leaf springs and a pinion snubber..as for the m/ts you'll need to experiment with them to see what pressure your car likes..mine hooks great at 15 psi's..
Click to expand...

Oh yeah, Randy's Ring and Pinion. Also installing green bearings while I'm at it.
 
Randys:thumrigh:i've had good luck with them,i'll be calling them soon myself to have another 489 with 4.30's and a spool built..my combo:340 stroked to 416,mopar crank,eagle rods,diamond 10.9 to 1 pistons,Edelbrock heads w/street port job nothing crazy just cleaned-up and polished,Comp magnum rockers,Lunati voodoo cam .533/.552,Air Gap intake port matched,quickfuel 850 carb,full msd ignition,tti headers..904 w/low first gear,3500 stall converter.8 3/4 w/3.91's and trac-loc unit..best e.t. so far 11.02@120 best 60' 1.42...hopefully i'll be in the 10's with the 4.30's...
 
Dam. That's one nasty little ride. What car? Any pics? Awesome combo. I also have a Quick fuel, however it's just a 750 D.P. With my current combo, do you think I can break 11's?
 
Heres a photo from e-town,if you get that thing to hook i don't see why 11's would be out of the question,you might benefit from a bigger carb though

DSCF0101.jpg
 
DEfinite a bigger carb I have a 825 and I wish I bought a 950.With that set up you should be in the 11s .What rpm does it cross the stripe with and what rpm is your cam?
 
Awesome car! Never ran the car before, so I don't know. Cam spec's from Hughes
Roller
242 and 246 @.050
.525 intake and .535 exhaust spec'd for 1.5's and I have 1.6 Crane rollers.
 
With the 275 60 15 the 410 isnt going to be much diff from the 391. But I would guess for street 410-430 and loose as much weight as poss. try the new tires with the 391 get a feel for what rpm your motor likes.
 
The motor combo sounds great.Is this going in a 69 charger? I have 410 in the scampi and run mid to low 11 hopefully low low 11 this year . I built the motor for 12s.but I weight 3140 with me in it.
 
No, it's going in my 68 Cuda Notchback. I went from power to manual steering(flaming river) and of course iron to aluminum heads, Centerline whees, 3.5 frontrunners, etc. I have a 998 w/low first gear and Dynamic converter @3700 stall. The Charger is getting a Ray Barton 528 Hemi later this year. I guess I would also like to know what you think I'd run in the 1/8th. Thanks for so much positive and honest feed back from you all.
 
69Chrgr said:
Street Strip. 68 Barracuda notchback, right around 3100 lbs. I presume. I went ahead and ordered a 3rd member w/powertraxx and 4.11's. Going from 26 inch diameter BFG's w/3.91's to 28 inch diameter M/T's w/4.11. Hope I don't lose too much gear. However right now it does nothing but spin the little BFG's and desperately need traction. I don't drive on the freeway as I live in a rural area. Just around town. Will trailer to 1/8th mile and 1/4 mile track.
Click to expand...

I'm glad you got a Powertraxx instead of a Auburn.

I installed a Auburn in my 03 Dodge Ram in 2005 and the Auburn broke last week. ??? :angry7:
 
You should have good luck with the trac-loc,thats whats in my pumpkin now..by the way whats Randys charging now for a center chuck set up now..
 
About $1400.00 for 3rd member assembly including PowerTraxx, Ring and Pinion w/warranty, Green Bearings, oil, and installation hardware and handling and shipping. Pretty much the whole ball of wax to do it right. Tracking it right now, should be here this afternoon. After that, I'll be visiting a certain little Trans Am at a local 1/8th mile track.
 
i dont think you have anything to worry about with the bird even with the 3.91s
 
340s that lunati 305 for big blocks really rocks for a hyd cam, ramps faster than any other hyd cam ive used,the faster the valves open and close the better . specs are .533 int. .552 exh 242 duration at .50 int 252 on exhaust, very sweet street cam for big block also, actually best ive seen, nice choice this cam will outperform the mp .509 all day and night long
 
mopar1962 said:
340s that lunati 305 for big blocks really rocks for a hyd cam, ramps faster than any other hyd cam ive used,the faster the valves open and close the better . specs are .533 int. .552 exh 242 duration at .50 int 252 on exhaust, very sweet street cam for big block also, actually best ive seen, nice choice this cam will outperform the mp .509 all day and night long
Click to expand...

Lunati cams will out perform any mopar cam...
 
340srule said:
Randys:thumrigh:i've had good luck with them,i'll be calling them soon myself to have another 489 with 4.30's and a spool built..my combo:340 stroked to 416,mopar crank,eagle rods,diamond 10.9 to 1 pistons,Edelbrock heads w/street port job nothing crazy just cleaned-up and polished,Comp magnum rockers,Lunati voodoo cam .533/.552,Air Gap intake port matched,quickfuel 850 carb,full msd ignition,tti headers..904 w/low first gear,3500 stall converter.8 3/4 w/3.91's and trac-loc unit..best e.t. so far 11.02@120 best 60' 1.42...hopefully i'll be in the 10's with the 4.30's...
Click to expand...
that lunati cam ramps super fast. I have one with the lifters brand new 284 int 252 exh. .050 242 int 252 exh jeez and it a hyd cam, 11.os is amazing ,good job, think im gonna hold onto this one and stuff it into a 0.35 over 400 block and a 383 steel crank I have. the voodoo is good but your #s surprise me. well done
 
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