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Old 06-03-2015, 04:49 PM   #81
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Originally Posted by carnut169 View Post
I ordered the Dorman HELP AC Bypass Pulley 34157
Amazon.com: Dorman HELP AC Bypass Pulley 34157: Automotive
Excellent info. Thanks.
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Old 06-03-2015, 04:49 PM   #82
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What are your impressions of the 3.42 and the MV5? For the tracks out here, the MV5 actually seemed like a better choice given the gobs of torque, but bench racing and reality are often at opposite ends of the spectrum.
I just asked that


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And now that you're on the road with it, what is your feeling on the getrag 3.42 ratio? That MV5 6 speed has a really short 1st/2nd and a really long 3rd, does the 3.42 make quick work of 3rd gear or does it drag on a bit?
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I *think* the 3.42 will be a good ratio for the track, but for a street car the 3.2x the V8R used would be better. The ratios used in the AY6 trans are a little odd. 1st is a stump puller. Great for burnouts! 4th to 5th is almost the same but 6th is a good bit taller. We'll see...
6th is basically an overdrive, with a big drop for the 1:1 5th down to 0.75:1. The thing I've tossed between, given a couple of our SoCal tracks that would see a 300hp car over 140mph, is whether it would be better to gear longer so that you don't need 6th at all at those tracks, but be stuck with longer gearing everywhere else, or just go short and accept that you'll need to nudge into 6th on the front straights for WSIR and ACS. You aren't accelerating much up at those speeds anyways, so I've decided it'll be better to go short on the rear ratio.
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Old 06-03-2015, 08:59 PM   #83
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Originally Posted by ThePass View Post
I just asked that






6th is basically an overdrive, with a big drop for the 1:1 5th down to 0.75:1. The thing I've tossed between, given a couple of our SoCal tracks that would see a 300hp car over 140mph, is whether it would be better to gear longer so that you don't need 6th at all at those tracks, but be stuck with longer gearing everywhere else, or just go short and accept that you'll need to nudge into 6th on the front straights for WSIR and ACS. You aren't accelerating much up at those speeds anyways, so I've decided it'll be better to go short on the rear ratio.
Yes, but I don't pay attention.

So if we're considering a 3.46 and a 3.23 rear end and an MV5 transmission, we get the following at 7,200rpm:

3.46 3.23

34 37 1st
65 70 2nd
96 103 3rd
120 129 4th
143 153 5th
170 182 6th

Assuming 205/50-15 tires

So how does this look for your Southern California tracks, such as Streets of Willow, Big Willow, Buttonwillow, Fontucky, Laguna Seca (okay, not SoCal but who doesn't want this on your list)?
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Old 06-03-2015, 09:03 PM   #84
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Originally Posted by cordycord View Post
3.46 3.23

34 37 1st
65 70 2nd
96 103 3rd
120 129 4th
143 153 5th
170 182 6th
I've been talking to Ryan here and there about diff ratios and based on this info I feel like it is a 3.73 diff or bust for a track focused car.
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Old 06-03-2015, 09:07 PM   #85
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I've been talking to Ryan here and there about diff ratios and based on this info I feel like it is a 3.73 diff or bust for a track focused car.
But....torque!!! Carroll Shelby said horsepower sells cars but torque wins races. LFX has what...278ft/lbs torque?! The first thing I wanted to do once I got the turbo on my car was go for longer gears. I'd think the same thing would happen with the LFX.
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Old 06-03-2015, 09:13 PM   #86
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Originally Posted by cordycord View Post
But....torque!!! Carroll Shelby said horsepower sells cars but torque wins races. LFX has what...278ft/lbs torque?! The first thing I wanted to do once I got the turbo on my car was go for longer gears. I'd think the same thing would happen with the LFX.
Won't argue there, the LFX certainly makes some decent torque. Most dyno sheets for the LFX in Camaros are showing around the low to mid 200's for torque at the wheels. For a pure track focused car, I still think the 3.73 will be a faster combination.

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Old 06-04-2015, 04:02 PM   #87
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I've got a whole mess of graphs that I've compiled to play with all the different ratio options. The main rub with the trans from the Camaro is the ratio spacing. Here's the Camaro's 6 speed with 3.42 compared to a Miata 5speed with 4.10 gearing to show just how short that 1st and 2nd are:





For the track, that's a useless 2nd gear, so I believe you're better off gearing for 3-5 use, rather than gearing long and having to dip into 2nd gear ever.

Addressing the real issue though would be to use a different transmission...

-Ryan
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Last edited by ThePass; 06-04-2015 at 04:22 PM.
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Old 12-31-2015, 09:34 PM   #88
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This is a beautiful build.

How streetable is this swap?
Can you retain AC and PS just like LS swaps?
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