3.55 or 3.70/3.73
03-15-2004, 08:38 PM
#1
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3.55 or 3.70/3.73
Still trying to figure this one out. It is my next mod in a month or two. Currently have 3.08.
Whata you think?
BTW, coming out of paint shop this week.
Whata you think?
BTW, coming out of paint shop this week.
03-15-2004, 08:43 PM
#2
Race Director
Re: 3.55 or 3.70/3.73 (OHSIXX)
4-spd? With a 4-spd, either one will be real blah on the freeway.
If you only plan on tooling around town in the car, I'd go with 3.70s.
Personally, unless the car is a drag race car, I don't really see the point of going higher numerically than 3.36, unless you have O/D. Even then, I think 3.08s with a ROD is the way to go.
-Steve
If you only plan on tooling around town in the car, I'd go with 3.70s.
Personally, unless the car is a drag race car, I don't really see the point of going higher numerically than 3.36, unless you have O/D. Even then, I think 3.08s with a ROD is the way to go.
-Steve
03-15-2004, 08:52 PM
#3
Safety Car
Re: 3.55 or 3.70/3.73 (Pacin'California)
With 1:1 ratio 3.7? is pushing 3400rpm's at 70. I had changed my 3.08 for 3.55 before I got the overdrive and take-off's were alot better. Now that I have the 200R4, I would like to have the 3.7?
03-15-2004, 08:57 PM
#4
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Re: 3.55 or 3.70/3.73 (redwingvette)
Is 3.55 the middle ground for city driving?
03-15-2004, 09:08 PM
#5
Re: 3.55 or 3.70/3.73 (OHSIXX)
i have had two 78's one with a 3.55 and one with the 3.08, the 3.55 car has a huge difference in the acceleration dept, but i can really tell the difference on the highway. I am one who does not like to rev my engine all that high for a long period of time. with the 3.55 my car turns 3000 rpms at 68 mph. I am not sure how fast you want to go either, but i have a huge problem with a friend of mine that blows by me in his mitsubishi eclipse at will. the car with the 3.55 is at 5000rpms at around 113mph. i will probably put the 700r4 in that car to get that overdrive. now after all that rambling, i like the 3.55 better.
03-15-2004, 09:11 PM
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Re: 3.55 or 3.70/3.73 (OHSIXX)
I would go 3.55. I have 3.73 and a 700R4. Acceleration is fun, but try to keep with the C4/C5 crowd on the interstate with their 6 speeds.
03-15-2004, 10:43 PM
#7
Team Owner
Re: 3.55 or 3.70/3.73 (BSeery)
BSeery - I don't understand your statement of not being able to keep up with C-4 or C-5. I have been driving around with a 700R4 since the late 80's. Like 1988 with a 4.11 with the over drive and it makes the rear ratio @2.87 in .70 final drive.
This also shows the beauty of 700R4 lockup transmissions. I'm not even doing half of my 7500 rpm at @104 mph
This also shows the beauty of 700R4 lockup transmissions. I'm not even doing half of my 7500 rpm at @104 mph
03-15-2004, 10:59 PM
#8
Team Owner
Re: 3.55 or 3.70/3.73 (gkull)
My speedo is a little fast - I tried to calibarate it. Here's the table, This doesn't allow for tire dia. growth.
Tire Diameter 26.8 inches
Rear Gear Ratio 4.11:1
MPH
RPM 1st 2nd 3rd 4th 5th 6th
1000 6 12 19 28 0 0
1500 10 18 29 42 0 0
2000 13 24 39 55 0 0
2500 16 30 48 69 0 0
3000 19 36 58 83 0 0
3500 22 42 68 97 0 0
4000 25 48 78 111 0 0
4500 29 54 87 125 0 0
5000 32 60 97 139 0 0
5500 35 65 107 152 0 0
6000 38 71 116 166 0 0
6500 41 77 126 180 0 0
7000 44 83 136 194 0 0
7500 48 89 145 208 0 0
8000 51 95 155 222 0 0
Maybe 3600 rpm was pretty close to 104 mph :flag
[Modified by gkull, 10:04 PM 3/15/2004]
[Modified by gkull, 10:05 PM 3/15/2004]
[Modified by gkull, 12:08 PM 3/16/2004]
Tire Diameter 26.8 inches
Rear Gear Ratio 4.11:1
MPH
RPM 1st 2nd 3rd 4th 5th 6th
1000 6 12 19 28 0 0
1500 10 18 29 42 0 0
2000 13 24 39 55 0 0
2500 16 30 48 69 0 0
3000 19 36 58 83 0 0
3500 22 42 68 97 0 0
4000 25 48 78 111 0 0
4500 29 54 87 125 0 0
5000 32 60 97 139 0 0
5500 35 65 107 152 0 0
6000 38 71 116 166 0 0
6500 41 77 126 180 0 0
7000 44 83 136 194 0 0
7500 48 89 145 208 0 0
8000 51 95 155 222 0 0
Maybe 3600 rpm was pretty close to 104 mph :flag
[Modified by gkull, 10:04 PM 3/15/2004]
[Modified by gkull, 10:05 PM 3/15/2004]
[Modified by gkull, 12:08 PM 3/16/2004]
03-15-2004, 11:13 PM
#9
Team Owner
Re: 3.55 or 3.70/3.73 (gkull)
Years ago I entered a Nevada open road race. It's called the Nevada Silver State classic. It's 92 miles of blocked off 2 lane hiway. During testing with 28 inch road racing slicks I tried to hit the speed gun at right on at 6000 rpm. My mph was 174 with 4.11 in OD.
03-16-2004, 11:17 AM
#10
Melting Slicks
Re: 3.55 or 3.70/3.73 (gkull)
I have 3.55's and also a serious problem with traction. I wouldn't go any smaller though.
[Modified by SuprJames, 10:18 AM 3/16/2004]
[Modified by SuprJames, 10:18 AM 3/16/2004]
03-16-2004, 11:24 AM
#11
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Re: 3.55 or 3.70/3.73 (SuprJames)
Looking at your mods, I think you would be happier with the 3.55. The 3.73 might be a little too much for your engine and you might run out of rpms a little too soon. Also going from a 3.08 to a 3.55 is a nice jump and you would be pleased.
03-16-2004, 11:26 AM
#12
Team Owner
Re: 3.55 or 3.70/3.73 (lotahp)
Looking at your mods, I think you would be happier with the 3.55. The 3.73 might be a little too much for your engine and you might run out of rpms a little too soon. Also going from a 3.08 to a 3.55 is a nice jump and you would be pleased.
03-16-2004, 12:15 PM
#13
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Re: 3.55 or 3.70/3.73 (GrandSportC3)
Thanks everyone. Going to go with the 3.55s. :)
03-16-2004, 12:44 PM
#16
Melting Slicks
Re: 3.55 or 3.70/3.73 (OHSIXX)
I think I have the 3.70 rear. It is great fun around town, but on the highway it is :nonod:
3000RPM at 60, 3500RPM at 70.
3000RPM at 60, 3500RPM at 70.
03-16-2004, 03:16 PM
#19
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Re: 3.55 or 3.70/3.73 (lotahp)
Is Bairs the best place to buy? So, I need the Ring and Pinion and differential rebuilt kit? What else? Should I get a new rear end cover?
03-16-2004, 03:19 PM
#20
Race Director
Re: 3.55 or 3.70/3.73 (lotahp)
Norm,
even with 3.73s, once my '82 gets into 3rd gear at the strip (5000 RPM?/60 MPH?), it just doesn't "pull" like it does in the lower gears, like it can't 'pull' the 3.73s (what do you EXPECT from a 'Cross-Fire'?).
I go 71+ MPH in the 1/8-mile, and trap just 20 MPH higher (90.89-best), at 4200-4300 RPM. If I had 4.10s, I think it'd go MUCH faster MPH in 3rd, making-up ET as it went.
:banghead:
[Modified by Glensgages, 3:26 PM 3/16/2004]
even with 3.73s, once my '82 gets into 3rd gear at the strip (5000 RPM?/60 MPH?), it just doesn't "pull" like it does in the lower gears, like it can't 'pull' the 3.73s (what do you EXPECT from a 'Cross-Fire'?).
I go 71+ MPH in the 1/8-mile, and trap just 20 MPH higher (90.89-best), at 4200-4300 RPM. If I had 4.10s, I think it'd go MUCH faster MPH in 3rd, making-up ET as it went.
:banghead:
[Modified by Glensgages, 3:26 PM 3/16/2004]