boldtx

Sorry I have neglected this thread. The alternator issue is an interesting one. A lot is up in the air now about weight. I am still wanting to do different brakes so I can fit the narrower tires and wheels for aero purposes. However, I have decided to go forced induction. Yep the goal is to get a F series procharger and with a smaller shot of nitrous maybe 50. Plan is to get close to that 1000whp number. Really I am just looking to easily hit 200 in the mile and not run such a large nitrous shot. Also might be switching to a 6060 as I have heard that even with a fully built T56 like I have anything over 800whp and 5th and 6th just cant handle that power level. I am letting my mechanic sort this out to see if it will really be an issue. The car should be getting picked up here shortly. Also the motor is coming out as well to for some changes handle the boost. Gonna be a fun build cannot wait.

neverstop

i posted this exact same question with t56 and >900whp at 5th and 6th gears and technically the t56 has narrower gears but there are guys on here who put down 1300whp+ through 5th gear in t56 repeatedly without issue. one guy was power shifting into 5th with 1000whp I believe. had zero problems. "Unreal" on here was putting down 1,100whp and crazy torque through his t56 at the track in 5th gear and like 30k street miles or something. zero issues.

I've been putting 900whp and 860tq (at the wheels) through my t56 for years and it's quiet and shift like butter. zero problems, including a handful of 1/2 mile track days to >170mph with countless pulls. I just use good fluid and overfill mine a touch (tilt the car when filling). my car has crazy torque too and probably making more torque (what really kills a transmission) than you will at 1k whp because i have 427 and some really high flowing heads and mid range cam with smaller blower. so my car is hitting my t56 harder than your setup will likely do.


I think the t56 thing is oversold and a t56 can handl 1000whp without issue as long as you're not driving like a total lunatic on the 4th to 5th shift you'll be fine for years. now the zr1 gearing in the tr6060 is a dramatic improvement so maybe that's worth it but I wouldn't do it for the strength issues.

neverstop

if you're set on going with a blower then I'd say an F194 pulley'd do the max on E85 would be an absolute monster on that motor

stevieturbo

Dont be fooled into thinking 5th gear will handle huge power. 170mph at the 1/2 isnt huge power by any means.

T56 is definitely a strong box, but it has limits, those will be different for all.

2 different T56's, both this year, car would typically run 180+ in the 1/2 ( when it makes it that far lol ) and is heavier and much less aerodynamic than a Vette.

I too had great confidence in the T56 until these happened 2 weeks apart at the end of July this year !
First one bust the slider when trying to go 4-5, and the second box ripped the teeth off 5th gear ( totally stock T56 0.74 ) at around 180mph.


Now both have lasted a very long time, the stock one was always kept as a spare. Now I need a stronger box, and even I'm a little wary of even a Magnum now ! Hence havent decided yet.

boldtx

Hey guys I appreciate the comments on the tranny debate. I have grenaded a T56 before and it was not pretty however it did not have the strengthened 5th and 6th like I do now. I really don't want to go through it again. It happened at 160mph and it made the car bounce off the rev limiter only way to stop it was shut the car off at probably 150mph. Financially it would suck to have to go to a 6060 but it might just have to happen.

neverstop

well the tr6060 is stronger in 5th and the zr1 gearing option is dramatically faster. when I was racing other vettes at the last 1/2 mile vs. my z51 gearing I think the zr1 5th gear is equiv to like 50-70whp

but that being said lot of people have put big power through t56 without issues.

https://www.corvetteforum.com/forums...-6th-gear.html

every 1/2 mile track is different. low 170s at my 1/2 mile track is about what the bmw s1000r bikes were running and takes 850-1,000whp depending on the car and setup. the traction is especially terrible there and a few other reasons why it's one of the slower 1/2 mile events around

stevieturbo

A lot ? and what is big power ?

Even a Magnum, about the only person I could find really making good traps was gnx7 in his RX7. Obviously he has fairly good aero and lightweight on his side vs some other vehicles. That said, he's almost hitting 200mph in 1/2, so really making some good power.

Obviously the shorter 5/6 ratios you use, that will inherently make them stronger due to gear sizes...ie 0.74 and 0.5 are probably the weakest respectively.

Even RSG who offer various builds, and a 9310 gearset for some of their Tranzillas which they proclaim a 1000lbft rating vs 850lbft for a stock magnum gear...when I pushed then about using it hard in 5th gear, was met with the response no those ratings do not cover 5th or 6th.

I've no doubt they probably would hold well, but they did put some doubt in my mind despite the extra cost they wanted for them.

But will a stock T56 run 1000hp or thereabouts ? Many have done it for sure....and quite a lot have broken it with less. It's always your gamble.

boldtx

Can't remember if I mentioned it I have whatever the craziest stage VI or so from rpm. My 5th gear is a .90 and 6th is a .79. Rear end is also built with a 2.92. I have done 170 in the half mile with 800whp. At the end of the day I agree running this much power and more it's also a gamble

neverstop

inspector12 was putting 1,200whp+ through his t56 in 5th gear for many pulls. unreal on here putting down 1,100whp at 1/2 mile in 5th as well. no problems. tr6060 superior but I think for centri and non turbo cars especially it's not required.

stevieturbo

What sort of speeds are they hitting ?

And up until a couple of months ago I'd have said a stronger box may not be required even at 1k....I no longer hold that view ! lol