What diff ratio

[StuartParticipant Newcastle355 vs caprice View build HERE Member since: November 9, 2015 Posts: 20]

Hey guys just after some advice about diff ratios, I’m in the process of putting a new 355 into my vs caprice, it’s 11-1 comp, crane 288, torque power single plane etc ect. Behind it is a built 4l60e, but what diff ratio? I have the choice of 3.08, 3.45 lsd or 4.11 mini spool as I have these in the shed. The car will mainly be a weekend toy and cope a bit of a hiding at powercruise sand stuff, I can’t see myself running it down the 1/4 very often if at all. So yeah any advice would be appreciated

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[cava454Moderator 93 VR BT1 View build HERE Member since: February 20, 2015 Posts: 2 390]

4.11 with a stall up around the 4800/5200 reign.

Also don’t think that box will last long.

[VRSenator065Participant Adelaide SAVR Senator LSx454 1960 Kombi (project) 1921 Nash Hot Rod (future project) View build HERE Member since: February 17, 2015 Posts: 5 777]

Yea i agree with cav, 4.11 if you stay with the 4L60 as you have the big overdrive of 0.7:1.

[StuartParticipant Newcastle355 vs caprice View build HERE Member since: November 9, 2015 Posts: 20]

Ah yes forgot to mention it’s got a 5000 stall. Na I’m not expecting it to last forever lol

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[VRSenator065Participant Adelaide SAVR Senator LSx454 1960 Kombi (project) 1921 Nash Hot Rod (future project) View build HERE Member since: February 17, 2015 Posts: 5 777]

Just get someone who knows what they are doing to set it up right in the tune.

[StuartParticipant Newcastle355 vs caprice View build HERE Member since: November 9, 2015 Posts: 20]

What do they rev like on the freeway with 4.11s?

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[cava454Moderator 93 VR BT1 View build HERE Member since: February 20, 2015 Posts: 2 390]

<del></del><del></del><del></del><del></del><del></del>that’s what the combo you have built needs mate.

High revs on the fwy is the sacrific we pay.

[[TUFFVQ]Participant Melbourne1991 VQ 304 View build HERE Member since: March 2, 2015 Posts: 171]

My T700 with 4.11’s and a 4000rpm lockup convertor runs below 2500rpm on the freeway.

[VRSenator065Participant Adelaide SAVR Senator LSx454 1960 Kombi (project) 1921 Nash Hot Rod (future project) View build HERE Member since: February 17, 2015 Posts: 5 777]

I reckon if you have a high performance  car and you are concerned with highway cruising your doing it wrong

[StuartParticipant Newcastle355 vs caprice View build HERE Member since: November 9, 2015 Posts: 20]

Sorry guys just curious that’s all

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[VRSenator065Participant Adelaide SAVR Senator LSx454 1960 Kombi (project) 1921 Nash Hot Rod (future project) View build HERE Member since: February 17, 2015 Posts: 5 777]

No need to apologize mate we are just joking around

There was another thread recently along a similar vane, and the general consensus was actually revving faster at freeway speeds doesn’t necessarily use more fuel as the engine is working less hard.

The advantage you have is overdrive in the 4l60 is very very tall at 0.7:1.  So you will be doing only 70% of the revs cruising that someone with a t400 or Glide (like me) are which don’t have an overdrive.  So if I am doing 3,000 at 100 km/h in my car you will only be doing 2,100 rpm.  Thats a hell of a drop which is why you can afford to run 4.11 and not have it revving its head off on the highway.

[Anonymous View build HERE Member since: January 1, 1970 Posts: 0]

I was asking the same question recently and have been convinced that 4.11 is the way forward. Have a play with this http://www.osella.com.au/gear-ratios.htm . Good for working out cruising RPM, speed in gears etc. Sounds like a tough unit you’re building there!

[ImmortalityParticipant 97 HSV Senator 185i 02 VX L67 Calais View build HERE Member since: August 31, 2015 Posts: 535]

4.11’s with a 4L60e and regular size 17’s would see about 2400rpm with a lock up converter.

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