JDMC5

iTrader: (3)

I'm doing a 4L80 swap in my 99 trans am. I have a 400-430 rwhp HCI ls1, I'm also running a circle d 3000 stall. If I had to guess what it will run it should be about 1.7 60ft 11.7 @ 117. Do I need the 300m input shaft or can I get away with stock? I plan on driving the car daily with track time maybe 1 time a year so I will be running street tires most of the time. Can you guys give a little insight on what's needed what's not and what's a good idea etc thanks

Jake's Performance

iTrader: (2)

Stock input would probably live. The question is, how much is the tow bill home if it breaks?

How much is the time worth to R&R the trans?

How much is the fluid gonna cost?

JDMC5

iTrader: (3)

Ok, I'm gonna go with the upgraded input shaft then.

Mystery Bird

iTrader: (7)

Mine is stock. I'm cutting high 1.4s in the 60.

Briou

iTrader: (1)

I am building a 700fwhp ls3 right now that will have a 4l80e behind it in a full weight 1970 Chevelle...the only upgrades I plan on doing is a rebuild kit with high friction clutch packs and the Transgo HD2 shift kit...I have a buddy with a 850hp turbo 5.3 in a fairmont that cuts 1.3s 60' and the only thing he has done to his 4l80e is the transgo HD2 kit, but only the parts that you do without tearing the case down....

Jake's Performance

iTrader: (2)

I've had stock input shafts live at 1200 RWHP in turbo combos. I've also seen them break behind stock 6.0Ls in 2500HD trucks.

The metallurgy on the stock shafts is very inconsistent and that is why we recommend a billet shaft at 750+ HP applications.

We warranty what we build and prefer to avoid failures. If you are building the trans yourself, you can definitely take that risk.

lsxstudebaker

this thing is gona be mean!

Briou

iTrader: (1)

Jake, do y'all sell the billet shaft on it's own??

Jake's Performance

iTrader: (2)

Yes,
They are $350.

got-a-ls1

iTrader: (12)

jake while were on the topic of input shafts... im running your stage 2 rebuild kit with a tci 300m input shaft and forward hub (you were out of stock of shafts at the time so figured id try the tci, good so far). what do you feel is a safe rpm differential to lock the converter (triple disk) im getting quite a bit of slip and want to lock third gear but i guess i dont know what type of rpm differential is safe to lock at. when i shift into 3rd gear the input speed of the trans is 4000 rpm while the engine rpm is 5700 rpm.

vwdave

iTrader: (3)

Im used to the Dodge 47's costing $750.

Jake's Performance

iTrader: (2)

Yeah the Dodge piece also has the hub. A 4" billet costs more than a 1.25" and requires more time on a machine to cut off the excess.

vwdave

iTrader: (3)

Makes sense.