What gears do I need?

Yep, 4.56's are the new 4.30's lol... but they are not a direct fit like the 4.30's, you have to modify the cross pin or something like that...
 
I'm going to go with 3.73s & a trac loc once I get the funds...
 
I'm going to go with 3.73s & a trac loc once I get the funds...

Seriously don't waste your time and money bro... with gears the amount of money and labor that is required you need to 'go big or go home'
 
I never agree with anyone on this, but anything over 3.73 is rather unnecassary to me. I've run them all, and I hate those super tall gears, and with 4.56 you no more than get going before its shifting. And cruising, you're wasteing gas. Unless your going to the track, ALOT, then 4.10 is absolute top of the spectrum and even those i'm not all that fond of.:cool:

373's are an absolute minimum for a base model Mark 8

when I went from the stock 307 gears to 373's I was actually shocked at how little difference it made to the car.

I did further research and found the 410's would have been a better swap for the 307 car.

With that said, if you have a 327 LSC then you'd be stupid to put 373's in and 410's would be "barely" worth the effort.

on a 327 car the best all around performance is going to come from a 430 gear.

the wide ratio 4r70w is well suited to run very steep gears.


DO NOT FEAR THE GEAR.

IMHO 456 would be just a little steep for my comfort level, NVH is gonna be alot higher.
 
I'm going to go with 3.73s & a trac loc once I get the funds...

410's if your car is a base model.
430's if it's an LSC.

whichever yours is, do this test.

get out on the hiqhway to your cruising MPH.
set your cruise control
then turn off your OD button.

if you have a base model that is going to be very close to your highway cruising RPM if you have 410's

If you have an LSC that's gonna be very close to your highway cruising RPM if you have 430's.

then ask yourself. "is that outside your own comfort level"?
 
being that I have a spare gearvendors unit laying around I was seriously thiniking of going that route with 4.56's....the real issue would become getting the power down.
another question (not wanting to hijack but more sideline)....which driveshaft is gonna be best with the 4.56 seeing as with the GV the shaft is still gonna be spinning like made even tho the motor aint.
 
being that I have a spare gearvendors unit laying around I was seriously thiniking of going that route with 4.56's....the real issue would become getting the power down.
another question (not wanting to hijack but more sideline)....which driveshaft is gonna be best with the 4.56 seeing as with the GV the shaft is still gonna be spinning like made even tho the motor aint.

I don't think you can cut down the two piece shaft. So unless you have a 93 or find a used shaft from one you need to have something made or cut something down.

Either way with the added length of the GV unit you will need a shorter drive shaft which will only help with keeping NVH away.
 
Granted to all will say, this isn't a mustang, I've owned several mustangs with all gear ratios. My absolute favorite for my daily driver was the 2.73's Yes they are horrific for line starts and the strip, but I could go into the 115 range in third gear without thinking twice about it, and my car dogged the :q:q:q:q out of an M3 with plenty of go to spare. 4.11's are soooooo tall, and anything over thats just :q:q:q:qing stupid insane for a daily driver. If high ass gears were that good, then factory stock muscle cars would have come with them. And the old days are gone old timer, we don't need gears like that anymore. Hell a piece of crap minivan can run the quarter in the same time some of the old muscle cars used to nowadays. 3.73 is the all around perfect combo, seeing as most of us aren't using the drag strip weekly, or even monthly most likely.:cool:
 
4.56's I THINK would be an awesome 1/4 gear with a gv unit in front of it....even on juice or with forced induction I cant see the thing ever needing anything beyond 3rd over....and for daily driving just let it run in over constantly....which would be the equiv. of a 3.28 (as in dman close to a stock LSC).

My biggest concern is dealing with the speedo caliberation...but I figure its gonna spend the next 6 months in the garage so I got lots of time to think
 
Speedo calibration is noting... gen 2's there is nothing to do, and Gen 1's you get a Dallas Speedcal.
 
Alright guys i am getting 4:10s on friday so I will let you know how it goes. Now what do I need to correct the speedometer. Is it just a gear in the trans or something else?
 
Granted to all will say, this isn't a mustang, I've owned several mustangs with all gear ratios. My absolute favorite for my daily driver was the 2.73's Yes they are horrific for line starts and the strip, but I could go into the 115 range in third gear without thinking twice about it, and my car dogged the :q:q:q:q out of an M3 with plenty of go to spare. 4.11's are soooooo tall, and anything over thats just :q:q:q:qing stupid insane for a daily driver. If high ass gears were that good, then factory stock muscle cars would have come with them. And the old days are gone old timer, we don't need gears like that anymore. Hell a piece of crap minivan can run the quarter in the same time some of the old muscle cars used to nowadays. 3.73 is the all around perfect combo, seeing as most of us aren't using the drag strip weekly, or even monthly most likely.:cool:
You're compering old muscle cars with huge push-rod engines that had insane low end torque to small modular engine with no low end torque :confused: These cars are pretty heavy ,have pretty much no low end torque ,they need as much gear as possible.

Like stated before, anything less then 4.10 is just waste of $$ on a Mark VIII.
 
go with 4.30's or 4.56's i have the 3.07's and they suck, 2.73's in my mustang (which as stated above) is nice on the highway, the top end is pretty much endless. however the acceleration isnt really there, i drove a crown vic with 3.27's and with 3.73's and at the track it only made a tenth of a second difference. if you do a lot of highway driving i'd go with 4.30's if gas is a concern go with 4.10's but if you wanna be happy then go with the 4.56's (which i will hopefully have in mine later this summer along with a possible 5 speed swap if i have time)
 
being that I have a spare gearvendors unit laying around I was seriously thiniking of going that route with 4.56's....the real issue would become getting the power down.
another question (not wanting to hijack but more sideline)....which driveshaft is gonna be best with the 4.56 seeing as with the GV the shaft is still gonna be spinning like made even tho the motor aint.
\\

I'm thinking you need to settle for the rpms your car will turn with 4.56's or dont get them. If your going to use a gearvendor overdrive why bother with the gear change at all. After you spend all that money on gears and drive shaft your probably going to lose the advantage of the 4.56's just with power lose turning the extra gear box. Why bother.

Also in the gen 2 car the speedo doesn't need to be corrected but the speed limiter needs to be addressed if you want to go faster than 100 mph. The limiter is run off the trans speed sensor I do believe. The speedcal will work for that.
 
Granted to all will say, this isn't a mustang, I've owned several mustangs with all gear ratios. My absolute favorite for my daily driver was the 2.73's Yes they are horrific for line starts and the strip, but I could go into the 115 range in third gear:

there is a HUGE difference between a 5 speed mustang and a 4r70w mark 8.
that's like comparing apples to orange juice.

in my 5 speed mustang 4.10's made the 4.30 first gear last about 8 feet, just as you described, but it's a whole different ball game without a 3.35 or 4.30 first gear like is found in the SVO mustang.

SO, your 273 geared mousetang ran 115 in THIRD gear...big WHOOP!

I dont guess you realize a stock geared mark 8 will run 105 in SECOND gear...huh?

third gear in a mark 8 moves into the 130-140 MPH range, almost a lightyear ahead of the mustang if you were only considering 3rd gear.

(lol)
 
98 - something is being missed...a gv unit will only add an overdrive ratio to each gear, it is incapable of taking you lower than your existing first....simply adding it to stock would only give me higher top end, but nothing shorter for the launch (with a stock 3.07 with the gv engaged it would act like a 1.79).

As far as parasitic loss, their design is very effecient..from experience I have no reason to doubt their claim of somewhere near 1hp to 400....so on even a blown or juiced mark you are only loosing 2 hp

As far as the speedo, car is a 94..i will be checking out dallas
 
Ok Tim I couldn't understand why the 4'56 be choosen of the 4.10's if the extra overdrive would be needed. One hp seems very low but what do I know. If thats it then its really doesn't effect he power loss. It must be some light weight piece.
 
GV also has a under drive unit that is used by the 4x4 crowd....leave the 3.07's and under drive it.
 
if I do gears on a 98 lsc with 4.10s will I need anything else done? or is it simple as installing gears and start to cruise? I dont want to mess with speed cals, sct tuners etc.. don't care if the speedo is off by a little.
 
well... you're gonna want the 93 driveshaft and then you're pretty much all set.
Since the Speedometer is driven off the front wheel abs sensor you dont have to worry about that.

BUT..you really will want to "mess" with a SCT tuner, because the shift shedule is going to be "compressed" for lack of a better term.

it's going to hit it's MPH based shift points sooner than before, and your probably gonna wind up in 4th gear at some stupid 32-34 mph when driving around town.

when I went to 373's the shift schedule got messed up a bit, I'm pretty sure 410's are only gonna be worse.

I must add, that I drove my car with a tune that was set up for the stock gears for about a year. it "wasn't all that bad".

But the car picked up quite a bit at the dragstrip and got alot "happier" on the street when I made the changes for the gears in the tune.
 
it'll shift out of first and into second too soon
and the same goes for 3rd and 4th

P.S. your step from 327's to 410's is almost the same as my switch from 307's to 373's. I hope you aren't dissapointed in the outcome as I was.

a proper swap from a 327 car, would be to the 430 gear.
 

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