Alwyn678

I am thinking of switching my 3:08's for 3:55's How are they at highway speed?? and off the line??

Shark Racer

Off the line, they're great. Good pull in first and second gear. TERRIBLE ON THE HIGHWAY. Get an o/d transmission if you plan on running on the highway, I was in the 3300-3500 range most of my highway travel. Hated it.
-Steve

QuickVet

my car came with 355s and i thought they were ok on the highway. now that i have 411s the car is not driven on the highway much. i would drive it ALOT more on the highway if i put the 355s back in. i think they are a good gears.

Monty

I 3.55'sin y car, and they are a good compromise between off the line acceleration and decent cruise rpm. I've always had an over drive transmission and generally cruise at 60mph at about 2100 rpm or so. I had 3.08's before, and thye provide much better acceleration.

GreyGhost

I like'm :D

73Ken73

I like my 3:55s . I take long trips and the highway isn't too bad. Would like to have a 5 speed and have it all but the 3:55s are a good comp.

LT1man

I have two 71's. One with 3.55 and the other with 3.70. I much prefer the 3.70 for off-the-line and mid-range. Highway travel with the 3.55 is marginally more comfortable than the 3.70.

Chris Fowler

I don't mind my 3:55 on the highway...it's a little high and I'd like an overdrive, but it's bearable

Chris69

Hated mine before the overdrive went in. Now hate it 'cause with the overdrive I could have used 3.70's. :rolleyes:

:nopity

RatRacer

I took mine out and put the 3.08 back in. Even brief highway time bothered me because the engine was revving so high. The 3.36 is a good compromise.

Garson

I have a 74 L-82 with a four speed and 3:55 rear gear. I make several long trips a year and find that at 70 MPH I am turning 3,000 RPM. Seems to be a good compromise for me.....

Garson :chevy

Stingy74

I used to have 3.55's behind my 700-R4. Reved something like 2100 at 60 some odd mph. I also had 3.08's (1900) and 4.11's (2600 I think). The 4.11's were the best but I wouldn't hesitate on the 3.55's. They are plentyful so that's a good thing.

Larry B.

A lot depends on the transmission and tire diameter. With a manual 4spd and stock 225/70/15 (27.4" dia.) tires the engine will run 3000rpm at 70mph. Then there are automatic with and without lok-up torque converters and the 700R4 has a .7:1 overdrive. :chevy

69er

I went from 3.08's to 3.55's.
At 70 MPH I'm at around 3100 RPM.
I only put about 2500-3000 miles a year on my '69.
If I drove her more I think I'd go back to the 3.08's.

Gary79

i'm running 3:55 with a 700r4 and it's a nice set-up. i had the rear end rebuilt when i did the tranny change and the mechanic said if the gears were not good to go to a 3:70,but my gears were still good,so i stayed 3:55. before 700r4 i turned close to 4k rpm @70 mph with 255/60x15 tires,so od became a must.

Rhubarb

You just want 3.55's because you know I can smoke your butt :)

I am turning around 3100 at 70MPH. Now that the car has the new cam it is much quieter and I don't mind at all.

I used to think that was a high RPM until I realized most cars are 2500+ at 70 ... but my C5 barely breaks 2K.

Alwyn678

Rhubarb..How is the Car running.??......You ready to go to Calhoun and line them up this Spring...?? I think I am gonna switch the gears while Jerry and i put the Converter in and shift kit this weekend...Come on by the new shop and give us a hand.....Plus I wanna go for a ride in that BAD 74 Roadster!! :cheers: :cheers:

SmokedTires

[Modified by SmokedTires, 11:06 AM 1/8/2002]

SmokedTires

I had 3.55's in my car & was pleased with them. I didn't think highway driving was bad with the 27" tires so I went up to 3.90's for even better acceleration and throttle responce for when I autocross my car. I love the 3.90's but will be installing a TKO O/D this spring so I can drive on the highway again with the 26" tires now on the car.

If your looking for more performance the 3.55's will be a good comprimise(sp?) between acceleration & highway. IMHO anything above a 3.70 ratio should have an O/D to be more practical. :)