la meanred

Well like i said i need some good gears for the 4l80e. My truck is a 2001 ex cab 1500 silverado it has a lq9 6.0 243 stock heads and a 236/242 580/590 cam 112 lsa and full bolt on except for the crank pulley o and a multy disc 3800 rpm stall. The truck has 373 with an eaton locker when i had my 4l60e with the same size conveter it would roas the tire from a 45 roll in cold weather dma nually shifting i loved how it pulled when it had traction. I BROKE too many 60s and i just stepped up to the 80e but now it wont even spin them from a 30 and first gear goes to 60mph then second to 80 or 90 and i im getting beat by a lot of people that count even catch up, i was thinking to go with 4.30s or 4.56 my tuner said that its bets to go with 4.56s but i think it would be too much i run 275/60/17 with are close to 30inch tires well if any body knows please help me out.:bang

best time 13.8 with street tires and a base tune on the 80e .:

fredkj3

iTrader: (1)

I run 4.30s and i am shifting out of first at 6300 and that was about 45mph on a 29.7" tire... 4.30s are enough... its almost too much.. this thing is at 2500 at 70 miles an hour

la meanred

Ok man thanks for the info I new 4.56 were too much thanks again.

GMCtrk

iTrader: (27)

The 80 is a power hogging parasite, but it's worth it for a reliability.

I went 13.73 on street tires with a stock cam 6.0, headers, and a 3600 10.5" stalled 80e.
Yes, the 80e does absolutely kill the thing out of the hole, it felt way stronger with the 60e, I do have 4.10s though.

fredkj3

iTrader: (1)

i actually like the 80e better on the street.. the truck isnt a big burnout anymore.... haha

sintered

I'm going to make the jump to an 80e/4.10s in my 05 yukon when the supercharger goes in, but will miss the tall OD. Gearing calculators show that 80e/4.10s in 1st and 2nd gear is very close to a 60e with 3.42s for shift points to give you an idea. You'll be turning ~2500rpm at 75 versus 2000 though. As long as your exhaust doesn't drone at that rpm the only real problem is MPG difference. 6.0s get thirsty above 2000.

Not knowing how deep your pockets are, there are lower ratio 1st/2nd planetaries available. But the good ones are expensive and require a complete rebuild of the PCM's shift tables. FLT advised me to stay away from the TCI units due to quality issues. Coan has the same ratios available but, again, real expensive to buy and install them. Machining is needed. http://www.coanracing.com/Catalog.asp?CatClass=02TU scroll down to the planetary section near the bottom. I explored this route but the cost ran me away. $1500 difference makes 19mpg vs 16-17mpg (plus a little more noise) go a long way before paying for itself!

la meanred

Man its hot out side but thanks guy for some more good info but i am just going to get some 4.30s hopefully i wont be so slow anymore lol.

fastnblu

iTrader: (2)

I was gonna suggest this, but see you're all over it.
I thought the lower planetaries were ~$875 or so. Those may've been the TCIs tho. Also, check out a guy named John Kilgore. He might be in that ballpark, again IDK since I'm not runnin a 80E. I know he was a THM400 wiz tho, so ...

IDK how long it would take to make up that difference in price & MPG (19mpg vs 16-17mpg (plus a little more noise) go a long way before paying for itself!), but it's not just price & MPG, but off the line ratio advantage that may be more important instead.

The nice 3.06 in the 60E vs the 2.48, & these planetary gearsets for 80E are just a few little things that kept me in a 60 series trans. If I ever cross the too much power bridge, well... when I get there I'll look closer at a 80, & only if I have to.

MPFD

iTrader: (5)

I run a 4.56 on a 255/70/16 street tires and it runs 2500 at 70 mph, 2730 at 75 mph (per snap on scan tool). I feel like thats very acceptable for the pick up in E.T. and MPH at the strip. I'm extremely happy with it, but I am running an FLT 4l60e and with the 3.06 first gear and 4.56 it pulls hard 60ft. times on 28" slicks...

oldred95

3.73s with 32 inch tires that measure 31 inches. 4L80E from a 6.5 turbo diesel truck and I'm still using that converter. It brake stalls to about 1500, maybe 1550. It can still get rubber from a 30 mph roll on a 2-1 down shift. I come out of 1st around 60 and 2nd at 88-90 right now at 5400 and 5600. To me it seems ideal. I know I wouldn't want any lower gears at this point. Just my 2 cents.