sincityvettman

Hi all, my question to all you big HP / TQ at what point is it necessary to upgrade the rest of the drive trsin? trans, rear end, propshafts, torque tube etc. Im adding a A & A blower systen and expecting 700 RWHP and 650 TQ. currently making 435/409.

sincityvettman

My car is 2003 Z06 with heads / cam/ long tube with high flow catts and Bissani cat back. 90mm Fast intake with LS 2 TB and 44# injectors.

neutron82

the clutch will need to be upgraded no question... as far as the rest it depends how you drive... sticky tires and hard launches at the drag strip and I wouldn't expect it to last very long but if you mainly do roll racing then it can last... I drove around on a stock trans/diff with between 7-800rwhp for about 2 years and it held up fine doing roll racing, I did have aftermarket motor and diff mounts so that probably helped... I ultimately swapped it all out but the stock stuff was still in good shape when it came out... on a side note you might consider selling the fast intake before it cracks

Naturally Vain

What cam do you have?

frodo84

Where are they prone to cracking? What alternative would you suggest?

neutron82

with boost it is a well known issue, the plastic is thin and they are muiltiple pieces so it isn't near as strong as stock... on an n/a setup they are fine though... believe it or not the stock intake is probably the best bet unless you are making real big power and/or spinning very high rpm

zeevette

I swapped out my FAST manifold for the stock LS6 intake when I SC'd; my car. Give up maybe 25 HP and gain 125 with standard pulley. Runs like butter with a blower cam and a good Tom Wong tune.

gimp

In my experience, anything beyond a naturally-aspirated pump-gas setup may need upgrades.

LS6 clutch should be fine to about 450-500 bhp. After that it might not be the happiest.

Trans and diff will start seeing issues with hard launches at lower power levels, at higher power levels it's just a matter of when, not if.

At 700, you're on borrowed time. You can upgrade now or you can upgrade later when things start to misbehave (or leave you stranded).

C5Dobie

I was looking into this as I'm @ similar power level cam/headers & was contemplating A&A kit. My car has just over 40k & is an 03Z. My tuner/builder obviously stated clutch needs to be replaced & would need replacing @ some point regardless @ 440whp as the mileage climbs may as well do it once & be done while its torn open = free labor

The axles/1/2 shafts on C5Z's are supposed to be fairly strong, & the diff is good enough provided you're not running it regularly @ the strip - if you were then beefing up the diff is a recommendation. Running meth injection & adding better rad/cooling is a good idea to improve longevity. I guess adding trans/diff bracing is recommended as well especially if you're not upgrading either of those parts from the start.

Also I think it makes sens to replace the torque tube bushings regardless same as clutch they're a wear item whether the car is modified or not & once its torn open easier to access.

Personally - I'll be adding trans/diff bracing, meth injection/bigger fuel system (in addition to what is offered by A&A), replacing torque tube bushings, adding an ECP rad. I won't be touching the diff or the 1/2 shafts - I already had the axle & case seals replaced along w/ the vent for the diff & I don't launch the car hard nor do I have much interest in 1/4 mile racing - I am more interested in road course racing.

PlanoLeMans

When i went to a twin turbo set up many years ago, we used a t6060 transmission that bolted right in. I believe it was sourced from rpm. They made a t6060 in a t56 case. The first gear was good to 63 mph or so, 5th was good to 204, and other gears spaced accordingly. The lost of mechanical advantage in first, i found, made it easier to launch. I decided to change gearing at the transmission and leave the diff at 3.43. We used a twin disc clutch from McLeod. The diff was harden, again sourced from rpm, with 300m drive shafts.
You can make the stock parts live, except for the clutch, if you are gentle with it. At 700+ whp, you can even pull on the t56 in 6th gear if you are gentle and with short duration. I did and the t56 did fine. I did the clutch immediately and the rest in stages. When you do the mods is dependent upon how you drive or like to drive.