DIY Ford 8.8 into V1 Build thread
#201
I went with an Iron housing after seeing this thread back in march.. apparent the front diff mount ears snap off. the weight was a non issue for me. plus its cheaper
makes perfect sense. I have the prothane bushings in the front diff bushings.. Im in for a urathane set for the rear aswell
makes perfect sense. I have the prothane bushings in the front diff bushings.. Im in for a urathane set for the rear aswell
I am not worried about it.
In fact if you read the thread that you posted above, they mention that it is mounted wrong.
Moot point.
I'll knock out the rear bushings in the junk subframe and take measurements for Revshift. I'm sure it would be easy for them to build a set. You will most likely need to remove the whole subframe to install the new bushing, there isn't enough clearance to remove the stock rear diff bolts with the subframe bolted to the car. Guess it's not a big deal if you already have the subframe down to replace the subframe bushings.
Yes, we are doing that, so did CS. I have yet to hear of a failure of this sort when mounted properly.
#203
Anyone else thinking about going with 3.27 gears on the back end?
If you look at the variants of the T-56 that shipped with the CTS-V, the GTO, Viper, Corvette, etc...you'll note that there's a 2.97 wide ratio and a 2.66 close ratio. I have a problem with the way the CTS-V is geared. We have too much gear and too little tire. Unfortunately, because of the weird, bastardized version of the T-56 we have, we can't shift worth a damn, and we can't change our gears without buying a whole new transmission from G-Force for $5000 (I called five T-56/TR6060 specialty shops to confirm).
First: 2.97 (CTS-V and GTO), 2.66 (Corvette and Viper)
Second: 2.07 (CTS-V and GTO), 1.78 (Corvette and Viper)
Third: 1.43 (CTS-V and GTO), 1.30 (Corvette and Viper)
Fourth: 1.00 (CTS-V and GTO), 1.00 (Corvette and Viper)
Fifth: 0.84 (CTS-V and GTO), 0.74 (Corvette and Viper)
Sixth: 0.57 (CTS-V and GTO), 0.50 (Corvette and Viper)
Differential ratio: 3.73 (CTS-V), 3.46 (GTO), 3.42 (Corvette), 3.07 (Viper)
See anything wrong here? We have the worst differential, subframe, transmission, and the least ability to carry wide rubber, and yet we have (by FAR) the shortest gears. Even with a 3.27, we're still carrying about 10% more gear than the stock Corvette. And for those of us who are planning on building 416+ CID LS3s and supercharging them, that gear ratio will really come in handy.
There are also some positive side effects. First, you can buy that $900 DSS aluminum driveshaft that has a critical speed of 150 mph and run it up to 172 mph instead of paying for their $1500, 250 mph carbon fiber model. That's $600 saved. Second, first gear suddenly becomes a little more useful, and you can finally get great fuel economy at some of the more typical cruising speeds (e.g. 45 mph in urban environments and 80 mph on certain highways).
The following is based on a little worksheet I put together that takes the minimum possible speed that you can run the engine in Gear X before it starts lugging and identifies the speed that you can hit at 2000 RPM before you need to shift to conserve fuel. Before you go off and yell at me for saving fuel, note: I either drive like I'm in an autocross event, or I cruise to save fuel. There's no middle ground. This is just an example of the conservative extreme.
================================================
T-56 2.97 wide gear ratio with 3.73 differential
900 RPM = 6 mph
2000 RPM = 14 mph in first
1150 RPM = 12 mph
2000 RPM = 21 mph in second
1225 RPM = 18 mph
2000 RPM = 30 mph in third
1325 RPM = 28 mph
2000 RPM = 43 mph in fourth
1375 RPM = 35 mph
2000 RPM = 51 mph in fifth
1375 RPM = 51 mph
2000 RPM = 68 mph in sixth
DSS Aluminum $900 Driveshaft: 150 mph critical speed (7000 RPM in 4th gear??)
================================================
T-56 2.97 wide gear ratio with 3.27 differential
900 RPM = 7 mph
2000 RPM = 16 mph in first
1150 RPM = 13 mph
2000 RPM = 23 mph in second
1225 RPM = 21 mph
2000 RPM = 34 mph in third
1325 RPM = 32 mph
2000 RPM = 49 mph in fourth
1375 RPM = 40 mph
2000 RPM = 58 mph in fifth
1375 RPM = 59 mph
2000 RPM = 85 mph in sixth
DSS Aluminum $900 Driveshaft: 172 mph critical speed (7000 RPM in 4th gear??)
================================================
Based on hand calculations, and by using various calculators, I think that we have a chance of breaking 10 seconds in the first generation CTS-V with a 416 CID LS3 and TVS2300 making above 700 RWHP (825 crank horsepower), provided that we can keep the transmission and differential from exploding and the wheels on the ground.
If you look at the variants of the T-56 that shipped with the CTS-V, the GTO, Viper, Corvette, etc...you'll note that there's a 2.97 wide ratio and a 2.66 close ratio. I have a problem with the way the CTS-V is geared. We have too much gear and too little tire. Unfortunately, because of the weird, bastardized version of the T-56 we have, we can't shift worth a damn, and we can't change our gears without buying a whole new transmission from G-Force for $5000 (I called five T-56/TR6060 specialty shops to confirm).
First: 2.97 (CTS-V and GTO), 2.66 (Corvette and Viper)
Second: 2.07 (CTS-V and GTO), 1.78 (Corvette and Viper)
Third: 1.43 (CTS-V and GTO), 1.30 (Corvette and Viper)
Fourth: 1.00 (CTS-V and GTO), 1.00 (Corvette and Viper)
Fifth: 0.84 (CTS-V and GTO), 0.74 (Corvette and Viper)
Sixth: 0.57 (CTS-V and GTO), 0.50 (Corvette and Viper)
Differential ratio: 3.73 (CTS-V), 3.46 (GTO), 3.42 (Corvette), 3.07 (Viper)
See anything wrong here? We have the worst differential, subframe, transmission, and the least ability to carry wide rubber, and yet we have (by FAR) the shortest gears. Even with a 3.27, we're still carrying about 10% more gear than the stock Corvette. And for those of us who are planning on building 416+ CID LS3s and supercharging them, that gear ratio will really come in handy.
There are also some positive side effects. First, you can buy that $900 DSS aluminum driveshaft that has a critical speed of 150 mph and run it up to 172 mph instead of paying for their $1500, 250 mph carbon fiber model. That's $600 saved. Second, first gear suddenly becomes a little more useful, and you can finally get great fuel economy at some of the more typical cruising speeds (e.g. 45 mph in urban environments and 80 mph on certain highways).
The following is based on a little worksheet I put together that takes the minimum possible speed that you can run the engine in Gear X before it starts lugging and identifies the speed that you can hit at 2000 RPM before you need to shift to conserve fuel. Before you go off and yell at me for saving fuel, note: I either drive like I'm in an autocross event, or I cruise to save fuel. There's no middle ground. This is just an example of the conservative extreme.
================================================
T-56 2.97 wide gear ratio with 3.73 differential
900 RPM = 6 mph
2000 RPM = 14 mph in first
1150 RPM = 12 mph
2000 RPM = 21 mph in second
1225 RPM = 18 mph
2000 RPM = 30 mph in third
1325 RPM = 28 mph
2000 RPM = 43 mph in fourth
1375 RPM = 35 mph
2000 RPM = 51 mph in fifth
1375 RPM = 51 mph
2000 RPM = 68 mph in sixth
DSS Aluminum $900 Driveshaft: 150 mph critical speed (7000 RPM in 4th gear??)
================================================
T-56 2.97 wide gear ratio with 3.27 differential
900 RPM = 7 mph
2000 RPM = 16 mph in first
1150 RPM = 13 mph
2000 RPM = 23 mph in second
1225 RPM = 21 mph
2000 RPM = 34 mph in third
1325 RPM = 32 mph
2000 RPM = 49 mph in fourth
1375 RPM = 40 mph
2000 RPM = 58 mph in fifth
1375 RPM = 59 mph
2000 RPM = 85 mph in sixth
DSS Aluminum $900 Driveshaft: 172 mph critical speed (7000 RPM in 4th gear??)
================================================
Based on hand calculations, and by using various calculators, I think that we have a chance of breaking 10 seconds in the first generation CTS-V with a 416 CID LS3 and TVS2300 making above 700 RWHP (825 crank horsepower), provided that we can keep the transmission and differential from exploding and the wheels on the ground.
Last edited by FuzzyLog1c; 01-03-2013 at 10:10 PM.
#204
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Fuzzy, My 3.31 gears were just delivered yesterday. My reasoning was a little more "simple" than yours in that I can't build boost in 1st and can't reach full boost in 2nd. It takes third gear to load up the motor enough to reach full boost. On top of the inability to load up the turbos I plan on running the car in the Texas Mile again, at my current power I was able to redline 5th and forced to shift to 6th. I'm nervous putting down big power in 6th and wrecking the transmission.
#205
Fuzzy, My 3.31 gears were just delivered yesterday. My reasoning was a little more "simple" than yours in that I can't build boost in 1st and can't reach full boost in 2nd. It takes third gear to load up the motor enough to reach full boost. On top of the inability to load up the turbos I plan on running the car in the Texas Mile again, at my current power I was able to redline 5th and forced to shift to 6th. I'm nervous putting down big power in 6th and wrecking the transmission.
#206
Fuzzy, Tick Performance also offers a Trans rebuild, and they state it is able to withstand 700RWTQ. It is a bit pricey, but another option. I know there was another shop near me, in South Carolina somewhere that was doing TR6060 retro's out of your T56. Wanna say the price was somewhere in the $2500-$3K mark for that, but that is a new trans, upgraded for extra power. I'll try to find info on that.
On topic- This thread is starting to make me want to upgrade my Gen 4 Diff. Damn you guys! This bug is hard to get rid of.
On topic- This thread is starting to make me want to upgrade my Gen 4 Diff. Damn you guys! This bug is hard to get rid of.
#207
Pricey but here's an option that may allow more flexibility down the road.....
http://forums.corvetteforum.com/c5-g...ansmisson.html
http://forums.corvetteforum.com/c5-g...ansmisson.html
#208
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I've talked to this guy before:
http://washingtondc.craigslist.org/m...519653410.html
Pretty sure hes on Ls1tech as well. I talked with him on the phone a year or so ago about rebuilding/upgrading a viper t-56 for my mustang. He seemed like a pretty cool guy and had reasonable prices at the time, although from talking to another trans builder, alot of the parts have gone up in price so not sure what it would cost now. Just an option, maybe more so for the guys in MD/DC/VA
Keep up the good work guys!
http://washingtondc.craigslist.org/m...519653410.html
Pretty sure hes on Ls1tech as well. I talked with him on the phone a year or so ago about rebuilding/upgrading a viper t-56 for my mustang. He seemed like a pretty cool guy and had reasonable prices at the time, although from talking to another trans builder, alot of the parts have gone up in price so not sure what it would cost now. Just an option, maybe more so for the guys in MD/DC/VA
Keep up the good work guys!
#209
Pricey but here's an option that may allow more flexibility down the road.....
http://forums.corvetteforum.com/c5-g...ansmisson.html
http://forums.corvetteforum.com/c5-g...ansmisson.html
#210
Fod, they're all selling the same parts. The only thing that differs is their "marketing strategy," as opposed to a rating, because a rating implies a warranty, and there is none on these parts.
Frankly, any continuous-time torque number thrown out there is pretty much baseless, because what usually breaks a transmission is shifting it under load (causing stress transients several times greater than the continuous torque rating). These shops admit that they haven't done qualification testing of their rebuild kits, so what you get is basically a "this guy runs our kit and he makes 700 RWTQ" statement that doesn't account for the driver, his shifting style, or the "grab" characteristics of his clutch (permutations include organic/ceramic/carbon fiber, single/double/triple, and sprung/unsprung friction disc or discs).
Frankly, any continuous-time torque number thrown out there is pretty much baseless, because what usually breaks a transmission is shifting it under load (causing stress transients several times greater than the continuous torque rating). These shops admit that they haven't done qualification testing of their rebuild kits, so what you get is basically a "this guy runs our kit and he makes 700 RWTQ" statement that doesn't account for the driver, his shifting style, or the "grab" characteristics of his clutch (permutations include organic/ceramic/carbon fiber, single/double/triple, and sprung/unsprung friction disc or discs).
Last edited by FuzzyLog1c; 01-04-2013 at 09:10 AM.
#212
Okay, so you, deciding to use the one above, are basing this off of what? Their claims, just like everyone else, are unfounded, right? Are you going with The Gear Box rebuild because it is the cheapest you've found?
#213
Correct. All of these kits include the exact same parts acquired directly from Tremec. Setting up a group buy feels like a scavenger hunt for the cheapest individual parts and the most amenable distributor.
#216
I too have been thinking about going a different gear ratio, but had not put pen to paper yet as I would like to see final drive ratios (1:1) just for ***** and giggles.
I really don't mind these kinds of off-topic discussions as I think they are healthy and promote open discussion that in turn really is on-topic.
As stated before, WHEN this becomes reality, I will start a thread, hopefully have it stickied, that has info and no q&A per say.
But we still have work to do, so keep up the chatter.
#218
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Just ordered axle stubs from DSS, not cheap at $250 each, but they are the only vendor I could find that makes a stub for 31 spline cobra carriers, and a 930 cv joint flange on the outside.
The Porsche 930 CV has been used for ages in the dune buggy scene, and is what most of the performance axle builders use for their "1000hp axles". There is a lot of aftermarket support for the 930, unlike the stock tripod type joint used in cobra axle shafts. If I break a CV I can find stock replacements for $50, or upgraded hardened/chromoly pieces for around $100-$150.
Picture of the stubs I found on the internet for reference, this is from a 8.8 swap into a BMW.
Porsche 930 CV's
The Porsche 930 CV has been used for ages in the dune buggy scene, and is what most of the performance axle builders use for their "1000hp axles". There is a lot of aftermarket support for the 930, unlike the stock tripod type joint used in cobra axle shafts. If I break a CV I can find stock replacements for $50, or upgraded hardened/chromoly pieces for around $100-$150.
Picture of the stubs I found on the internet for reference, this is from a 8.8 swap into a BMW.
Porsche 930 CV's