Forged & Turbo Daily Driver
Agree, flex fuel super easy on these cars.
If I can make a stock 4l60 live you better be able to make a 6l80 live. I'd go 7875 turbo, small turbo cam, small stall, flex fuel if you have e85 in the area and call it good with a good tuner. It'll drive nice, spool fast, be fun, and potentially get better highway gas mileage. My 383 turbo was pulling 30mpg on the highway.
T56+turbo+cubes+baby cam+3.5 gear in the 9"=70 mph cruising at low RPM and high map=good gas mileage. It was actually on the cover of High Performance Pontiac awhile back with a heading of 30mpg hahahah. If I can make a stock 4l60 live you better be able to make a 6l80 live. I'd go 7875 turbo, small turbo cam, small stall, flex fuel if you have e85 in the area and call it good with a good tuner. It'll drive nice, spool fast, be fun, and potentially get better highway gas mileage. My 383 turbo was pulling 30mpg on the highway.
TECH Junkie
Joined: Jul 2015
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I wouldn't wish a 4L60 on anyone lol. It depends on what you call live as well as your budget. To me it wasn't worth the cost of building a 6L80 so I moved on because both a TH400 and a manual swap are cheaper and more reliable. 6L80 usually works decently until somewhere between high 9's low 10's 600-700hp but still eventually break. I know someone will say tuning is key and I've seen pretty much every tuner from this country 6L80's break built or not. Shop built trans from the likes of Century and Circle-D and home built trans with parts from PATC transmission fail as well. Some will say a 6L90 is stronger but I see 2-3 CTSV's per track day munch a trans, so while I'm sure it's possible to make them live its not worth the hassle to me especially if you want to make well in excess of 800hp.
Family car TR6060, 5.3L on 28" tire you basically idle down the highway at 70 MPH. In the twin turbo vette I routinely get 25+ MPG and if I could stop getting into boost I'm sure I could see 30 but that's no fun.
While I'm not personally a fan of TH400's for a street car, I didn't lose much more then 2MPG switching from a 6L80 to a TH400. That was with 3.45 gear on 28" tire both having a fairly loose converter. TH400 was fine on the highway as well and I had a big cooler on it with a deep pan. Switching from a 6L80 to a TH400 also dropped like a second at the track, the 6L80 first gear is horrible for traction if you make any power.
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Verdad Gallardo TECH Junkie
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While I'm not personally a fan of TH400's for a street car, I didn't lose much more then 2MPG switching from a 6L80 to a TH400. That was with 3.45 gear on 28" tire both having a fairly loose converter. TH400 was fine on the highway as well and I had a big cooler on it with a deep pan. Switching from a 6L80 to a TH400 also dropped like a second at the track, the 6L80 first gear is horrible for traction if you make any power.
I wouldn't wish a 4L60 on anyone lol. It depends on what you call live as well as your budget. To me it wasn't worth the cost of building a 6L80 so I moved on because both a TH400 and a manual swap are cheaper and more reliable. 6L80 usually works decently until somewhere between high 9's low 10's 600-700hp but still eventually break. I know someone will say tuning is key and I've seen pretty much every tuner from this country 6L80's break built or not. Shop built trans from the likes of Century and Circle-D and home built trans with parts from PATC transmission fail as well. Some will say a 6L90 is stronger but I see 2-3 CTSV's per track day munch a trans, so while I'm sure it's possible to make them live its not worth the hassle to me especially if you want to make well in excess of 800hp.
Whats the plans for the car if you're not selling it, save for a rear and run a 9?
TECH Junkie
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I was going to go to the track for a hail mary pass, just to get the single digit slip a couple weeks ago as the weather was perfect, then quit tracking the car. But the track closed early for the season, but I think I'm going to quit tracking it anyway, even without the single digit slip. Anymore, I just cruise around town every now and then, sits in the garage more than anything though. But to answer the question, no 9 inch is in the near future.
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Guy over at JackTuned posted on Facebook about his first 1000 horsepower build, because it made 680whp or something with a TH400, and that TH400 drivetrains typically see ~35% drivetrain loss. When I tried to explain it didn't work that way, he got pretty upset and started quoting people. If that's the case, my little 4.8/TH400 combo is making over 900 at the flywheel on just 11 PSI.
I think with a 3.07 of gear and 28" tall tire, mine is at like 2500 RPM on the highway. That's not too bad until you consider I have no body on the car and sidepipes with a decent sized cam. I still don't mind cruising it on the highway.
I was going to go to the track for a hail mary pass, just to get the single digit slip a couple weeks ago as the weather was perfect, then quit tracking the car. But the track closed early for the season, but I think I'm going to quit tracking it anyway, even without the single digit slip. Anymore, I just cruise around town every now and then, sits in the garage more than anything though. But to answer the question, no 9 inch is in the near future.
Ya if I was stuck driving an auto with a low rev limit I may as well get out and walk... be about as much fun.
TECH Junkie
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Not many people are willing to spend the money to build a 4L60 that will handle decent power and by decent I don't mean running 11's. Throw 800+whp at a 4L60 and it doesn't last long at all.
Ya if I was stuck driving an auto with a low rev limit I may as well get out and walk... be about as much fun.
Ya if I was stuck driving an auto with a low rev limit I may as well get out and walk... be about as much fun.
. Slap in the face to all my heads cam buddies, got me all busted up in tears over here. TECH Junkie
Joined: Jul 2015
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763/891 T56
742/1045 TH400. I'll admit, torque is suspect with the 400, converter probably. I feel that as long as the converter is a solid piece, one that isn't being ran through, it really doesn't affect the power to the ground nearly as much as most think.
742/1045 TH400. I'll admit, torque is suspect with the 400, converter probably. I feel that as long as the converter is a solid piece, one that isn't being ran through, it really doesn't affect the power to the ground nearly as much as most think.