Rear end gears & tires spinning!!

Topic: Rear end gears & tires spinning!! (Read 1885 times) previous topic - next topic

Rear end gears & tires spinning!!

April 02, 2005, 11:23:33 PM

hey guys,
just a quick qusetion i have a 87 cougar xr7 witha 7.5 rear with stock 2.73 gears and i going up to a 4.10 with the 2.73 gears when i go to do a burnout the tires will spin for a bout 15-20 feet then just cut off but the rpm are at like 3000 when it just stops spinning and then the car goes. also i runa 15 flat quater mile what do you think i will be running with 4.10 gears.
thanks Jason

Re: Rear end gears & tires spinning!!

Reply #1 – April 03, 2005, 12:01:24 AM

well, if you have an automatic 410s might be okay. how much street driving do you do? id go maybe 373...thats a pretty sugniffigant jump from 273s.

your not going to get 15flats with just a gear change i dont think...what other mods do you have?

Re: Rear end gears & tires spinning!!

Reply #2 – April 03, 2005, 10:14:08 AM

Quote

i have a 87 cougar xr7 with a fms E 303 cam ,speed pro pistons, block bored out 30 over ,mustang headers2 1/4 inch, flowmaster lers, aod with transgo shift kit. i have stock HO intake and throttle body and stock rear end gears.

Those are his current mods that he has run a 15 flat with.
I believe the thread also stated stock heads and near stock or stock compression. Also a 2.2 60 ft.
I'd go 3.55's or 3.73's and port that lower intake to take advantage of the E cam.

Re: Rear end gears & tires spinning!!

Reply #3 – April 03, 2005, 11:53:44 AM

if the suspension is stock maybe its time to think about suspension. the gears will help a ton. might make the tires spin more on the street but will get the car moving much better and keep it in a sweet spot through your 60" your car should accelerate more than pull the engine down. i assume you allready know this and thats why your askin about gears...

back in the day i has a sport. i had rebuilt the AOD in this car with a beauman valve body recallibration kit (stage3, very firm with even regular acceleration, somewhat a mistake)w/WOT overdrive, frictions, steels, servos, PI stallion converter (2800 rpm stall i think it was), turbo coupe rear end with a rebuilt trac loc and 355s, front turbo coupe brakes with mark vii callipers, advanced timing, underdrive pullies, and a flex fan.

the car ran a best of 15.8 from what i remember. it was some time ago. i think you should be where you want to be. souldnt be too far from 14s. my mark viii ran 14.9 with a converter, chip and k&n.

Re: Rear end gears & tires spinning!!

Reply #4 – April 03, 2005, 09:23:56 PM

what size do standard 1987 5.0 t birds have in the rear end 8.8 or the 7.5

Re: Rear end gears & tires spinning!!

Reply #5 – April 03, 2005, 10:43:21 PM

Quote

what size do standard 1987 5.0 t birds have in the rear end 8.8 or the 7.5

7.5" open