dizwiz24

ive had a mild centrifugal super harged car for a few years now.

its entry level hp is way less than what i read many of you have - which makes this a great place to ask this question...

lets say you are driving and a perf car notices you and is challenging you (on a racetrack of course)...

they have a head start and you need to downshift. you need speed quick.

would you think it be a disaster (ie. tire traction and mechanicAlly (stock bottom end piston/crank/valves, internal supercharger gear and belt speed changes) to suddenly downshift at a highway cruise rpm to a gear that would bring you up to 4500 rpm and gun it?

i generally ease into it, for traction and component longetivity reasons. stock bottom end also.

imho doing what i have suggested on our cars would be very risky (suicidal traction wise and mechanically)

these arent 4 banger hondas.

that said, has anyone here downshifted quick like that? (traction control off)

what was your hp level And what happened?

ajrothm

If it's an auto with the 4l60, pull it out of OD manually, then hammer it in 3rd and let it downshift from there... 4l60s can handle a WOT 3-2 downshift but definitely not a 4-2 downshift.. Other then that, it will be fine... (Assuming you have good tires and aren't going to wreck it.)

If it's a manual, you can pretty much do what you want. I used to go from 6th to 3rd and hammer it all the time.. Hell I'd throw it in 2nd at 50 mph and stab it.. All stock LS6 motor/trans, making 600rwhp at that time. I always used drag radials tho.

dizwiz24

just under 600 rwhp is where im at.

mine is a 6 spd.

if im taking a passenger on a hell ride, i love to wind it up to about 4000 rpm in 1st, let it coast for a second, then just slam the gas.

if im on drag radials, and good pavement, the thing is like a slingshot (as we all know).

but i have never tried a highway hard downshift.

ajrothm

Only thing bad about hard downshifts and immediately stomping the gas is its hard on the pot metal synchronizer keys and eventually it will break the 4th gear key, getting it stuck in 4th.

I would take it from 6th to 3rd, let the clutch out completely, then stomp the gas.

95wht6spd

C4 with 3.45 rear, correct?

Forcedvert

Make sure you are in straight line and if car has competitive driving mode I would leave it turned on! And practice with no one around so you don't end up on utube corvette fail video we have seen too many of those!




Im at 550/530ish I do it all the time (built a4)

ajrothm

Here is my 3-2-3 WOT downshift....about 850rwhp at the time.

JT FRC 00

First know or understand the limits of your tires if there not a DR or soft compound tire that helps with traction if not warmed up some prior to doing it. Downshifting from 5-6th to 3rd can be done at highway speeds, just rev it up some to help match the higher RPM'S in the lower gear and then let the clutch out completely right before nailing it. Less stress on the drive components and rearend. Have fun and be safe

CamminC5

And that's why I'm doing an automatic.

PEETYZ

Sounds good AJ!

I personally almost always rev match when down shifting. Saves your breaks too.


OP,

Are you a MN12( Z06) or MN6 ( Base) transmission? In my Z06 on the Highway ( in mexico) 70mph rev match and drop it into 3rd and once the clutch is out let it eat. lol

95wht6spd

I think he has a C4, that's why I asked him about the rear end gear above. If stock, it would be a 3.45 in a Dana44, with a Zf6 trans.

MVP'S ZO6

Gosh that thing sings Alan.

stevieturbo

Sounds like perfectly normal driving to me. Any actual race scenario could be a hell of a lot more abusive than what you suggest would ever be and you'd be doing it multiple times throughout the duration of a race.

Absolutely nothing to worry about at all.

jbsblownc5

Nice highway Pull!!!

ONE BMF

Bad idea maybe at 50 or 60 but at 80 mph on the highway and when Lambo's, Ferrari's or any other fools think they're about to smoke some vette ,, i slam her down into 3rd which puts me right in the center of my powerband and they never now what hit them,,,,i send them home with no doors. No contest,, undefeated record !!

fisher auto

4th to 3rd pull @70 oh hell yea!!!

Smoove

point and shoot.