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Okay, I'm gonna do it, really I am....

I'm on the "VERGE" of getting a 95 WX3, and I'm planning on putting the T-56 in it, instead of the 94 9C1 that I was going to use....

The Cop Car got the 4.10's in it, but.....

Are 4.56's better? Who's got them? Reluctor?

Guess I missed a lot.....All the "STICKY's" went away....

Talk about a GIANT loss of knowledge....

Thanks
Gene
 

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Well, considering I think 4.10's are great for a 28"+ tire, daily driver, with the 4L60E... I'd have to say 4.56's with the T56 would be a no brainer, from a starting gear, and crusing RPM in OD stand point. For the reluctor, get a custom unit for about $100 from Bob Shirley.
 

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Shifting out of first while turning is a pain in the a$$ and I have 4.10's. 6th gear is about the same as the 4l60 was.

If I had to do it all over again, I might even consider 3.73's. Just my 2 cents worth.

Sharkx
 

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I am with Sharkx on this one, many say 4.56's are the way to go, but I am the same, I like shifting don't get me wrong, but I don't like shifting my a$$ off while cruising through a light unless I just let it rev. But that is just us. 4.56's would put your RPM a couple of hundred higher than the 4L60 at 75, but with my 315/35/17's I have cruising at 75 with 4.10's = 2100 RPM or there abouts.


Mike
 

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Here is a simple Excel sheet I use to compare different gear ratios with different transmissions and tire sizes. It will give you what your RPMs will drop to shifting into each gear at redline, the top speed in each gear, and how many RPMs you will be turning in OD at different speeds. It already has the two Camaro T56s and 4L60E in there. You can change any of the values that are in blue. The one most people will need to change is the revs per mile value for their tire size in cell J3. I usually get that value from TireRack or the manufacturer's website. PM me if you find yourself using it and have any questions.

I agree with jayoldschool and put 4.10s in mine because I plan on running shorter tires.
 

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Here is a simple Excel sheet I use to compare different gear ratios with different transmissions and tire sizes. It will give you what your RPMs will drop to shifting into each gear at redline, the top speed in each gear, and how many RPMs you will be turning in OD at different speeds. It already has the two Camaro T56s and 4L60E in there. You can change any of the values that are in blue. The one most people will need to change is the revs per mile value for their tire size in cell J3. I usually get that value from TireRack or the manufacturer's website. PM me if you find yourself using it and have any questions.

I agree with jayoldschool and put 4.10s in mine because I plan on running shorter tires.
Awesome spreadsheet!!! Exactly all the data I have been looking for in one spot. Thanks.
Question, you have the 742 revs/mile as the baseline, is that fora the stock Impala tire - 255/50/17?
 

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I don't mean to sound insulting, but this and other similar discussions revolve around a gearing difference of only 10%.

I ran 3.73, 4.10, and 4.56 with the T56.

With the above experience driving in town, on the road, and at the track: 4.56.

My buk2fifty. YMMV.

Just think long and hard about it - because this decision is not cheap. THEN..... there's finding a decent installer worth his $alt. And most folk DO NOT want to do this twice.
 

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Go 4.56's. If you don't want to shift in the intersection, (which I don't see how you're doing this unless you shift at 3k or something), start in second when you're just driving it mildly down the street. When you want the hard acceleration, then you still have the awesome lower first gear AND 6th gear highway driving is still right in the neighborhood of 3.08's and a 4L60E as far as rpm's go.
3.73's with 2.66 1st gear T-56 are way too high IMO. I had them for almost 2 years.
 

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Thanks for sharing that spreadsheet, jloehlein, that is AWESOME! :)
 

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Go 4.56's. If you don't want to shift in the intersection, (which I don't see how you're doing this unless you shift at 3k or something), start in second when you're just driving it mildly down the street. When you want the hard acceleration, then you still have the awesome lower first gear AND 6th gear highway driving is still right in the neighborhood of 3.08's and a 4L60E as far as rpm's go.
3.73's with 2.66 1st gear T-56 are way too high IMO. I had them for almost 2 years.
^^Damn good advice^^
 

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I don't mean to sound insulting, but this and other similar discussions revolve around a gearing difference of only 10%.

I ran 3.73, 4.10, and 4.56 with the T56.

With the above experience driving in town, on the road, and at the track: 4.56.

My buk2fifty. YMMV.

Just think long and hard about it - because this decision is not cheap. THEN..... there's finding a decent installer worth his . And most folk DO NOT want to do this twice.
Well said Wood on the gear install. If you are ever in Michigan I will show you what I am talking about in my car :) I like the 4.10's in mine, but my tire height is not stock, 25.4, versus 27 or something like that on a 255/50. If the calculations come out right you will see with a 4.10 gear in my car, with the 315/35's, I am right around a 4.23 gear or so. Buh is right though you can start in second that is for sure. And if I had a stock tire height on my car the gears would be perfect.
 

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Here is a simple Excel sheet I use to compare different gear ratios with different transmissions and tire sizes. It will give you what your RPMs will drop to shifting into each gear at redline, the top speed in each gear, and how many RPMs you will be turning in OD at different speeds. It already has the two Camaro T56s and 4L60E in there. You can change any of the values that are in blue. The one most people will need to change is the revs per mile value for their tire size in cell J3. I usually get that value from TireRack or the manufacturer's website. PM me if you find yourself using it and have any questions.

I agree with jayoldschool and put 4.10s in mine because I plan on running shorter tires.


Great reference thanks for that. Stock tire revs are 746 for a 255/50/17. For comparison sake and to prove what I was talking about above, with 746 in the field J3 under the 4.56 RPM's at 80 it reads 2268, if you put my size 315/35/17 which is 785 and look at the 4.10 scale like I have you will note at 80 my RPM's are 2146. Hence why I felt 4.10's were perfect in my eyes and if I wanted to run 3.73's it would be close to the 4.10 scale with a stock tire.


Mike
 
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