RPM at 70MPH ???????
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RPM at 70MPH ???????
I am trying to set up my gear ratio for my 13b in VW bug, If you know what your RPM is at 70 MPH, that will help me to decide what gear ratio to use. Please post what year and what engine (Turbo/ N/A) and Manual or auto...Thank you...
#2
Top Down, Boost Up
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In what gear?
Top Speed Calculator
You'll find transmission and differential gear ratios, along with tire sizes, in the standard spec sticky: https://www.rx7club.com/new-member-r...atures-963417/
Top Speed Calculator
You'll find transmission and differential gear ratios, along with tire sizes, in the standard spec sticky: https://www.rx7club.com/new-member-r...atures-963417/
#3
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In what gear?
Top Speed Calculator
You'll find transmission and differential gear ratios, along with tire sizes, in the standard spec sticky: https://www.rx7club.com/new-member-r...atures-963417/
Top Speed Calculator
You'll find transmission and differential gear ratios, along with tire sizes, in the standard spec sticky: https://www.rx7club.com/new-member-r...atures-963417/
#8
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I did go through all the #'s with different tire size options. I really appreciate the info you sent as it was very helpful and contained other cool facts that I didn't know about...
i just wanted to see what other people were getting for their stock and other modified setups...
#9
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Originally Posted by red94yj
I have a first gen with a 12a carb'd. I'll let you know in about an hour
With my stock 12a with stock trans and rear gears im about at 3400 rpms around 70mph
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#11
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0.806 5th gear (jspec transmission), 4.1 rear end and 225/45/17 tires puts my car at 3150 RPM @ 70 mph & 3600 RPM @ 80 mph.
An S5 us-spec TII transmission with 0.719 5th would be nicer at 2800 RPM @ 70 mph, 3200 RPM @ 80 mph. But I do find it very nice to have plenty of passing power in 5th.
An S5 us-spec TII transmission with 0.719 5th would be nicer at 2800 RPM @ 70 mph, 3200 RPM @ 80 mph. But I do find it very nice to have plenty of passing power in 5th.
#13
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I'm already seeing alot of differnt #'s.
This is very interesting to me. Please if you can, specify as many details as you can. Such as: Turbo/non-turbo
Maunual/automatic
modified/stock
tire size
gear ratios if known
Miles per gallon Average
This is very interesting to me. Please if you can, specify as many details as you can. Such as: Turbo/non-turbo
Maunual/automatic
modified/stock
tire size
gear ratios if known
Miles per gallon Average
#14
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Gearing information for rx7's. I dunno about auto trans gearing, but it was 4-speed, thus the taller final drive:
Transmission
Differential Interchanges
Are you doing this for fuel efficiency? I'd shoot for 3000 rpm and choose whatever gear gets you near there. Best case scenario, you're going to pull low (mayyybe mid) 20's constantly driving at 70 mph.
Transmission
Differential Interchanges
Are you doing this for fuel efficiency? I'd shoot for 3000 rpm and choose whatever gear gets you near there. Best case scenario, you're going to pull low (mayyybe mid) 20's constantly driving at 70 mph.
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Gearing information for rx7's. I dunno about auto trans gearing, but it was 4-speed, thus the taller final drive:
Transmission
Differential Interchanges
Are you doing this for fuel efficiency? I'd shoot for 3000 rpm and choose whatever gear gets you near there. Best case scenario, you're going to pull low (mayyybe mid) 20's constantly driving at 70 mph.
Transmission
Differential Interchanges
Are you doing this for fuel efficiency? I'd shoot for 3000 rpm and choose whatever gear gets you near there. Best case scenario, you're going to pull low (mayyybe mid) 20's constantly driving at 70 mph.
Fuel efficiency was the main goal in tuning the RPM to the 1800Lb. VW beetle. I feel (just a gut feeling no real data) that I can max out my MPG at around 2600 RPM. Because it will be carbureted at first my MPG might not be as good as it will be once I tune it with mega squirt. Plus there wont be any emissions to lower the MPG. I was just wondering what other configurations were out there in the RX-7 community. I am some what limited on my gear configurations (that is with out spending big $$$). My 4 final gear configurations put my RPM at either 3700, 3400, 3000, 2700. Then I might be changing to larger tires later.
#17
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1987 N/A 13B EFI, stock ECU and everything else except exhaust and emissions delete, swapped into 2300lb. 1979 SA22, .711 OD (FC 5spd NA trans), 3.90 rear gear, 23.4 inch tall rear tire. RB header, dual 2.5" exhaust, 2800 rpm @ 70mph. 26mpg highway in need of a tune (which I'll get to one of these days )
#19
I was looking for the 70MPH RPM in fifth gear. Thats the only one that matters to me. What I'm trying to find out is what the best RPM at 70 MPH for my rotary powered VW bug should be. I figured that since the RX7 is around 2900, that I could go to a lower RPM with my much lighter VW , but aerodynamics matter too...
#20
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12a stock
My bone stock 83 gsl revs around 4 grand doing 130 km/h ( about 80 mph) in fith. I can't remember what it does around 70, it's been wintering in storage for the last 5 months. Not sure it this helps.
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