Best diff gear for Boost in M6
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Best diff gear for Boost in M6 Hi guys,
I'm going to be putting a 9' in my LS1 Z28 in Spring and will be boosting the car the following year (D1SC).
I heard 4.10's are too much gear with my planned setup. What is best? 3.90's or 3.73's to put in my new rear end??
I want to get the most that I can out of my forced induction setup but also somewhat driver friendly.
I'm going to be putting a 9' in my LS1 Z28 in Spring and will be boosting the car the following year (D1SC).
I heard 4.10's are too much gear with my planned setup. What is best? 3.90's or 3.73's to put in my new rear end??
I want to get the most that I can out of my forced induction setup but also somewhat driver friendly.
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A 3.90 is not that different than a 4.10
I'm switching from 4.10 to 3.50 which is good for 140ish mph depending on how high you rev it and tire diameter
My recommendation is to search similar setups to determine an approximate mph in the quarter and select gears based on that.
I'm switching from 4.10 to 3.50 which is good for 140ish mph depending on how high you rev it and tire diameter
My recommendation is to search similar setups to determine an approximate mph in the quarter and select gears based on that.
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A 3.90 is not that different than a 4.10
I'm switching from 4.10 to 3.50 which is good for 140ish mph depending on how high you rev it and tire diameter
My recommendation is to search similar setups to determine an approximate mph in the quarter and select gears based on that.
I'm switching from 4.10 to 3.50 which is good for 140ish mph depending on how high you rev it and tire diameter
My recommendation is to search similar setups to determine an approximate mph in the quarter and select gears based on that.
I have a D1 with ~15psi of boost with 3.73s in my M6. There's sometimes that I think I'd rather have 3.42s instead since I blow off the tires in 2nd gear as soon as I hit boost. It's better now with the new R888s, but still, I think a 3.42 gear might be better.
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But overall 3.42's would be better huh?
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btw would the fact that I will be putting a blower cam in the car before I throw the blower on make any difference? Prob not but jw.
I want 140mph out my 4th gear. I dont want to run around on a 28" tall tire all the time so im putting in 3.25s
A 3.70 rear gear with a 28" tire works out to nearly the same as a 26" tire and 3.25s.
I have 3.70s (w/ 26" tire) in my car now and i hate them with a turbo. im out of gear just after 120 and the car is really starting pull at that point, it sucks. I wouldnt even be able to make a full 1/4mi pass without hitting 5th.
A 3.70 rear gear with a 28" tire works out to nearly the same as a 26" tire and 3.25s.
I have 3.70s (w/ 26" tire) in my car now and i hate them with a turbo. im out of gear just after 120 and the car is really starting pull at that point, it sucks. I wouldnt even be able to make a full 1/4mi pass without hitting 5th.
This is a good thread, as my build ill be keepin the built T56 i have, and im ordering a new rear end, and this thread just helped me pick what gears i want to run with my new rear end
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I want 140mph out my 4th gear. I dont want to run around on a 28" tall tire all the time so im putting in 3.25s
A 3.70 rear gear with a 28" tire works out to nearly the same as a 26" tire and 3.25s.
I have 3.70s (w/ 26" tire) in my car now and i hate them with a turbo. im out of gear just after 120 and the car is really starting pull at that point, it sucks. I wouldnt even be able to make a full 1/4mi pass without hitting 5th.
A 3.70 rear gear with a 28" tire works out to nearly the same as a 26" tire and 3.25s.
I have 3.70s (w/ 26" tire) in my car now and i hate them with a turbo. im out of gear just after 120 and the car is really starting pull at that point, it sucks. I wouldnt even be able to make a full 1/4mi pass without hitting 5th.
Im glad you think so man, I was searching for a similar thread before I posted but could not find anything really.
I would go with 3.25 cus im running and 26" tire (seems like you are too)
If i was going to run a 28" all the time, id go 3.50. Both of those combo's give me 140mph in 4th.
I should probably mention im only spinning my car 6k, so if you spin higher, youll get more out each gear combo.
A 28" tire and 3.70s will take you to a lil over 130 in 4th. A 3.50 rear gear with 26" tire will do the same thing.
Now what does change somewhat for each combo of tire/gear is your 1-3 shifts points. Some combos let you get a lil more mph in each gear which may or may not be what you want. if my memory is correct, then with a 28" tire and 3.50s i can stay in first gear to nearly 60mph. with a 26" tire and 3.25s i barely get over 50mph in first. (if my memory is wrong, then the opposite applies)
it may be beneficial to dyno your car, look at your powerband and go from there. its also easier to get traction with a 28" tire. just some food for thought
If i was going to run a 28" all the time, id go 3.50. Both of those combo's give me 140mph in 4th.
I should probably mention im only spinning my car 6k, so if you spin higher, youll get more out each gear combo.
A 28" tire and 3.70s will take you to a lil over 130 in 4th. A 3.50 rear gear with 26" tire will do the same thing.
Now what does change somewhat for each combo of tire/gear is your 1-3 shifts points. Some combos let you get a lil more mph in each gear which may or may not be what you want. if my memory is correct, then with a 28" tire and 3.50s i can stay in first gear to nearly 60mph. with a 26" tire and 3.25s i barely get over 50mph in first. (if my memory is wrong, then the opposite applies)
it may be beneficial to dyno your car, look at your powerband and go from there. its also easier to get traction with a 28" tire. just some food for thought
28" tires do simplify things though