Transmissions and DrivetrainNeed help with your trans? Problems with your axle?
Welcome to ThirdGen.org!
Welcome to ThirdGen.org.
You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join the ThirdGen.org community today!
swapped my worn one wheel peel 9bolt 3.27 to a 3.55 ford 8.8. but i kept the stock speedo and gears in the trans when i rebuilt it. i figured it was close enough to not cause a huge incorrect speed gap.
but will the speedo read higher or lower than im actually going now?
This ad is not displayed to registered members. Register your free account today and become a member on ThirdGen!
__________________ Formula 383 HSR 9.3:1
SCAT 9000 cast crank, SCAT 4340 forged rods/ARP rod bolts, SRP forged pistons/JE rings, ported HSR, HSR port matched to felpro1206, 58mm TB, grannelli MAF
30lb SVO injectors, patriot 195cc aluminum heads port matched to felpro 1206
XFI280 comp cam, 230/236, .571/.569
1.6 aluminum full roller rockers
handmade aluminum RAM AIR Headman LTs, true dual 3" with 3" xpipe
700r4, built by me, can handle 700hp, beast sunshell, billet servos, transgo shift kit, yadda yadda
march pullies, smog deleted, AC/heat removed
160 thermostat, 166 on fan switch 8pt CEE roll bar, with swing out door bars, hand made thru floor SFC, Jegster tunnel mount tubular TQ arm, Jegster drive shaft safety loop
UMI LCA relocation brackets, UMI adjustable panhard rod, hand made tubular LCA's,TDS wonderbar, KYB struts and shocks, cut moogs 5664/5665, moog suspension tierods etc
SSBC force 10 front calliper upgrade kit, slotted and drilled rotors, stainless braided lines all over car, rebuilt master, SSBC proportioning valve, rebuilt booster, ford 8.8 11.5" rear disks FORD 8.8, rear disks, 3.55 gears, rebuilt carbon fiber clutch trac lock(posi) with f150 preload spring, 28spline axles, ARP cap studs and moser aluminum support girdle.
SLP 17x8's fronts wrapped in Nitto 555 ZR rubber
rears will be 17x10.5 ford rims with 315's
NO2 150shot comin soonnnn!! or dual rear mounted turbos
Sponsored Links
Registered users do not see this ad. Click here to register for free!
you'll be going slower than what your speedo says. So when it says 60, you should be doing about 55.4, and when it says 30, you should be doing about 27.7 It really does work as percentage. 5 mph off at 60 does not mean 5 mph off at any or all speeds. If you're running an automatic I can help you calculate the correct speedo gears.
hmm well thats good iguess. at least i wont be getting that many 10mph above the speedlimit tickets
yes im running the 700r4, speedo gears are stock with the red one on the tail shaft and the light green one on the speedo. rear gears are 3.55 from the stock 3.27. what speedo gears would i need?
Assuming your driven is 42 tooth, and assuming you're running a 245/50R16 rear tire, or something the same outside diameter of 25.65" or so, you just need a gray 15 tooth drive gear, GM PN 8642620
or dual rear mounted turbos 
