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719 views 7 replies 5 participants last post by  ZumpTA 
#1 ·
I'm looking in too a 96 Formula Firebird 5.7 long tube headers, with 3in exhaust , cam, 150 HP wet shot of nitrous, 4 10 gears with superior axles, new front and rear struts , Brakes, tires ,nice car.. really nice .
My question is it worth buying w 4 10 gears of I wanna drive daily & cruze? Probably won't be using the nitrous
 
#2 ·
Depends whether it's a T56 (6-speed manual) or a 4L60E (4-speed automatic).

The 4.10’s go very well with the T56 because of the steep overdrive 5th (0.74:1) and 6th (0.50:1) gears. Still be loping along at reasonable RPM in 6th gear on the freeway. The 4L60E likes a set of 3.73’s better, with the 0.70:1 O/D 4th gear.

Interesting they only upgraded the axles. The 10-bolt rear carrier with the 7.625” ring gear is the weak point. Heavy mods + N2O + sticky tires will break things up.
 
#3 ·
Uh..it sounds like you like to quote the racy features. Are you sure that's what you want for street driving? I would.... but then I am insane ;-) Also, INTO is one word!
 
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#6 ·
I'll have to disagree, other than the fact the RPM with stock setup is 1,800 @ 80 MPH. My spreadsheet for the T56 with stock 3.42 gears shows 1,793 RPM @ 80 MPH.

With the stock tire diameter/3.42 rear, shift points at 5,800 RPM:

1 - 48 MPH
2 - 72 MPH
3 - 99 MPH
4 - 129 MPH

Throw in a set of 4.11's:

1 - 40 MPH
2 - 60 MPH
3 - 82 MPH
4 - 107 MPH

Where is the problem?

OK... if you're running 110+ MPH in the 1/4-mile you get forced to shift into 5th O/D. Although most likely to run that MPH you would be shifting a modified engine higher than 5,800 RPM.

Don't confuse the 1994-2002 T56 (2.66:1 1st gear) with the 1993's two T56 options, RPO "M28" 3.36:1 first gear, or "M29" 2.97:1 first gear. The 93's would turn into stump pullers with 4.11's.

I swapped in a Strange 12-bolt with 3.73's. Even with a slightly modified LT1 engine that was happier at 6,000+ RPM the 3.73's were disappointing. 9% more grunt with the 3.73's can't come close to the 20% extra with 4.11's.

And, I believe I already indicated that 3.73's are preferable for most 4L60E owners.
 
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#8 ·
Don't confuse the 1994-2002 T56 (2.66:1 1st gear) with the 1993's two T56 options, RPO "M28" 3.36:1 first gear, or "M29" 2.97:1 first gear. The 93's would turn into stump pullers with 4.11's.
Before YouTube existed, there was an auto-centric video sharing website called StreetFire.Net. There was a guy I was subscribed to with a "bolt-ons" '93/M29 and 4.11's. His thing was completing the 1/4 before an import could cover the 1/8th. Never got old watching the import start from halfway up the strip, only to be passed in the last second by the T/A. ...good times!
 
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