I’m not picking up what you’re laying down here.
A 4.11 or 4.56 will need a full manual valve body so he can leave in 2nd gear. I’d not recommend that. It is would be cheaper and more user friendly imo to put in a mid 3.__ something ratio.
Rear end gearing
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A 4.11 or 4.56 will need a full manual valve body so he can leave in 2nd gear. I’d not recommend that. It is would be cheaper and more user friendly imo to put in a mid 3.__ something ratio.
With your 28" tall tire and the 4L80's final drive of .75:1 and 4.11 gears my calculator indicates that with a highway speed of 70mph would be @ 2650 RPM. Having said that, is your converter a lock type? If not I would imagine your highway RPM to more like 2900 to 3000.
https://www.roadrunnerconverters.com/product/10-4l80e-3200-3600-stall/ this is the converter I got. I believe it is lockup
The link to that converter indicates it's a lockup converter. That is a good price for a 4L80 billet converter. I'm very curious as to how it works out.
What are you using for engine management/ecm?
What are you using for engine management/ecm?
TCI Auto Gear Ratios - TCI® Auto
Are you looking TCI Auto Gear & PG Low Gear Ratios? Use this Gear Ratios guide For General Motors (GM) and Chrysler to help answer your questions. The Powerglide planetary is referred to as a compound gear set with a ring gear. Figures on this page demonstrate the various elements of this...
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200-4R:
4L80E:
and old muscle cars:
I don't see the problem here?
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I'm just concerned about the turbo. They like load so I didn't know if it's gonna be okay with 4.11sTCI Auto Gear Ratios - TCI® Auto
Are you looking TCI Auto Gear & PG Low Gear Ratios? Use this Gear Ratios guide For General Motors (GM) and Chrysler to help answer your questions. The Powerglide planetary is referred to as a compound gear set with a ring gear. Figures on this page demonstrate the various elements of this...
200-4R:
View attachment 171373
View attachment 171374
4L80E:
View attachment 171377
View attachment 171378
and old muscle cars:
View attachment 171379
I don't see the problem here?
You're correct Mike, the car will drive at the given rpm's with a 28" tire at 70. At 75 with the 4.11's he'll be at 2800. Yes that will work, but why do it? It will be harder to launch (bad) , he'll be in OD at the end of a 1/4 (very bad), and it will run just fine at 22-2400 RPM'S on the highway.
The BTR stage 2 turbo cam is not a 'big' cam in old school standards. The LSA is more a 70's grocery getter LSA, and the ICL is around 111 IIRC, which is not old school 'big'. I'm saying that the motor will run easily at highway speeds below 2500 - why not use it if he needs the gears at the big end of the track and to help launch the car anyway?
Seeing that he already has quite a nice plan, i.e cam, converter, trans, turbo, then if he has a MPH goal for a 1/4, then that should dictate his gearing. I know I fubar'd with this and am living with what I have until the time comes. I know that I have to change gears only because of the speed at the line - my 3.73's are too low for me to get over 145mph. I think the OP will be in a similar situation. I know I'm going to have to decide to go to either a 3.55 or 3.31 (Ford) when the time comes. If the OP puts in the 4.11's, he'll be needing to change gearing the 1st time he can make a 17-20psi hit for the length of the track.
The BTR stage 2 turbo cam is not a 'big' cam in old school standards. The LSA is more a 70's grocery getter LSA, and the ICL is around 111 IIRC, which is not old school 'big'. I'm saying that the motor will run easily at highway speeds below 2500 - why not use it if he needs the gears at the big end of the track and to help launch the car anyway?
Seeing that he already has quite a nice plan, i.e cam, converter, trans, turbo, then if he has a MPH goal for a 1/4, then that should dictate his gearing. I know I fubar'd with this and am living with what I have until the time comes. I know that I have to change gears only because of the speed at the line - my 3.73's are too low for me to get over 145mph. I think the OP will be in a similar situation. I know I'm going to have to decide to go to either a 3.55 or 3.31 (Ford) when the time comes. If the OP puts in the 4.11's, he'll be needing to change gearing the 1st time he can make a 17-20psi hit for the length of the track.
My point is there are many factors at play here, many of which have not been thought through or discussed. I must have missed OPs goals... and complete build specs. Because the only question I am answering is will a turbo 5.3 backed by a 4L80E on 28" tall tires and 4.11 gears work on the street: Which is yes, and just fine.
Is it best suited for a 8 or 9 second car? Don't know. OP didn't state an exact combination or goals. So we are doing a speculative @*ss grab in the dark here (must be Friday). Just can he drive around on 4.11s and it will perform fine. Do a gear swap if you can afford it, and you have specific goals in mind. Optimize the combination.
The whole "turbo load" issue is relative to the application. Me? I am fine giving up some "load" off the line to protect my fragile rearend and transmission. One thing I am not worried about is going 7000+rpm through the traps with a junkyard engine... especially with a suitable cam.
Is it best suited for a 8 or 9 second car? Don't know. OP didn't state an exact combination or goals. So we are doing a speculative @*ss grab in the dark here (must be Friday). Just can he drive around on 4.11s and it will perform fine. Do a gear swap if you can afford it, and you have specific goals in mind. Optimize the combination.
The whole "turbo load" issue is relative to the application. Me? I am fine giving up some "load" off the line to protect my fragile rearend and transmission. One thing I am not worried about is going 7000+rpm through the traps with a junkyard engine... especially with a suitable cam.
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