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Topic: I know nothing on gear ratios (Read 5291 times) previous topic - next topic

I know nothing on gear ratios

Reply #15 –
No I was agreeing with you. I went from 2.73 to 3.73 and its night and day difference.  Best mod I made so far. I never ran an overdrive before so I was thinking the 4.11 would be to much, if I had it to do over I would have took the 4.11s. By the way, I'm running an aod.

I know nothing on gear ratios

Reply #16 –
Great Randy that is what i thought. If the aod in fact is .67 in OD then 4.11 would have been a tad better. But nothing wrong with the old TRIED AND TRUE 3.73 Thanks
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

I know nothing on gear ratios

Reply #17 –
I put the 345 out there because there plenty and cheap. Being it's still a stock SD. Jump up Hp then he should start looking for a 8.8. My ? would it be worth putting 373 or 411 in a 7.5 , If you can buy an 8.8 already geared. Iv'e built my 7.5 already so it only took time, can he? also it may be getting harder to find an 8.8 from a tc soon.
Old Grey Cat to this.88 Cat, 5.0 HO, CW mounts, mass air, CI custom cam, afr165's, Tmoss worked cobra intake, BBK shorty's,off road h pipe, magnaflow ex. T-5,spec stage 2 clutch, 8.8 373 TC trac loc, che ajustables with bullits on the rear. 11" brakes up front. +

I know nothing on gear ratios

Reply #18 –
Actually the 7.5 is not that WEAK. They can handle a modded 302 fairly well. The axles are the same as the 8.8 and if the HP is under 350 +or -
they do last if set up correctly. With an auto 350 HP is  not a problem for a 7.5.    Naturally an 8.8 is the best but not always necessary. Thanks
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

I know nothing on gear ratios

Reply #19 –
Quote from: TOM Renzo;362933
Actually the 7.5 is not that WEAK. They can handle a modded 302 fairly well. The axles are the same as the 8.8 and if the HP is under 350 +or -
they do last if set up correctly. With an auto 350 HP is  not a problem for a 7.5.    Naturally an 8.8 is the best but not always necessary. Thanks

I agree about the toughness, Mine held up well, still is in something else now.What I'm getting at right now is how much does he want to spend to set up a 7.5 toward buying an 8.8 that will bolt right up? With the gearing already in place?
Old Grey Cat to this.88 Cat, 5.0 HO, CW mounts, mass air, CI custom cam, afr165's, Tmoss worked cobra intake, BBK shorty's,off road h pipe, magnaflow ex. T-5,spec stage 2 clutch, 8.8 373 TC trac loc, che ajustables with bullits on the rear. 11" brakes up front. +

I know nothing on gear ratios

Reply #20 –
Ok then he needs to find an 87-88 auto to get the 3.73 gears. Then either convert to disc or transfer his drums over. Either way he has a lot of work to do and find an exact axle in the JY. Then he is SET. So let him start looking. Thanks
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

I know nothing on gear ratios

Reply #21 –
I've got a 3.73 rear (8.80 in the garage (No brakes at all), sitting on jack stands.......tripping me every time I walk by it. LOL.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

I know nothing on gear ratios

Reply #22 –
Quote from: vinnietbird;362952
I've got a 3.73 rear (8.80 in the garage (No brakes at all), sitting on jack stands.......tripping me every time I walk by it. LOL.


That's why you shove it in the corner like I did with the 88 XR7 8.8 I just bought:hick:.

I would go with 3.73 gears. I had them with the old standard 5.0 in my car and it really woke it up. I was turning about 2400 rpm at 70 on the highway. Now with the non-lock-up converter I'm running it's more like 2800-2900 rpm at 70....
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

I know nothing on gear ratios

Reply #23 –
What I recall reading on here or on the corral, or wherever, was that 1985 and older Trac-Lok 7.5's used an Auburn carrier which was weak, and of course an open diff 7.5 is garbage too. After that year though, 7.5 trac-loks were a Dana unit and are much stronger.
1987 20th Anniversary Cougar, 302 "5.0" GT-40 heads (F3ZE '93 Cobra) and TMoss Ported H.O. intake, H.O. camshaft
2.5" Duals, no cats, Flowmaster 40s, Richmond 3.73s w/ Trac-Lok, maxed out Baumann shift kit, 3000 RPM Dirty Dog non-lock TC
Aside from the Mustang crinkle headers, still looks like it's only 150 HP...
1988 Black XR7 Trick Flow top end, Tremec 3550
1988 Black XR7 Procharger P600B intercooled, Edelbrock Performer non-RPM heads, GT40 intake AOD, 13 PSI @5000 RPM. 93 octane

I know nothing on gear ratios

Reply #24 –
The Trac Loc is a less aggressive, street-friendly limited slip suitable for daily driven vehicles and mild off-road use. This unit uses clutches and is Rebuildable.

Auburn gear High Performance posi for Ford 7.5". The Auburn gear limited slip uses a long-proven cone design to provide traction for performance and off-road applications.

Actually the AUBURN IS STRONGER!!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

I know nothing on gear ratios

Reply #25 –
4.10s here. Had 3.73s with 225/50/16s. I had an extra 8.8, so I rebuilt the posi, added an extra clutch and installed a set of 4.10s. Swapped out the rear and went to 255/50/16s and actually picked up mileage! The reasoning was that I could play with different tire sizes if I went to slicks.
  I'm with TOM on gear. My Comet ran 11.9xs with a 289 ,6.00s a 2.78 liberty top-loader in full race trim. When we put it back to street trim, my street gears are 5.43s and 375/50/15 Pro-Tracs.....and NO OVERDRIVE!  LOL!

  NEVER FEAR THE GEAR!  :mullet:
84 COUGAR/90 HO, 1.7RRs, performer RPM,700DP, equal length shorties, stainless EXH ,T-5,Hurst pro-billet, KC clutch, 8.8/ 4.10s, line-lok, bla ,bla, bla.
71 COMET/289,351w heads, 12.5 TRWs, 750DP, Liberty TL, 9"/6.00s, 11.9x @112 , bla,bla,bla.

Never shoot your mouth off, unless your brain is loaded! ....I may get older, but I'll never grow up!....If you're not laughing, you're not living!  :laughing:
 

I know nothing on gear ratios

Reply #26 –
I have 3.73 with a c4, first gear is a joke and if I had OD it would probably be fine. I had several v8 foxes and pretty much all were 2.73, biggest jump I did on those was 3.27 which actually gave me better mpg. Guessing it helped the motor not lug as much.
88 Turbocoupe: Coast High Performance 331 kit 28oz balance, Comp XE264HR14 cam, 58cc 185 afr heads, 1.7 roller rockers, Mass-Flo EFI (was POS to setup and their techline is a joke at best)
Full 1 5/8 primary equal length headers, 2 1/2 exhaust, Full manual reverse VB c4 and baked off clear coat "BECAUSE RACECAR"

I know nothing on gear ratios

Reply #27 –
Quote from: TOM Renzo;362863
Available ratios on the 8.8 DIFF

2.73  3.08  3.27  3.31  3.55  3.73  3.90  4.11  4.30  4.56  4.88  5.13  5.71  6.14

 
Add 3.15 and 3.31. These are on newer Fords with 8.8 rears.
2003 Marauder 300B
1996-97 Cobra wheel straight but weathered (For Sale)
84 TC manual shifter handle no  (For Sale)

BTW, I had a 1988 T-Bird Sport way back when. I found out that it was totalled shortly after trading it in. It still has the ignition switch recall to date.

Special thanx to EricCoolCats for showing me to this site.:bowdown:

I know nothing on gear ratios

Reply #28 –
3.55s aren't a bad choice if you have a 5-speed but with a AOD 2.40 1st gear automatic, anything less than 3.73s are for sissies... My Lighting pickup has 4.10s from the factory, no way I'd want less gear in it... I recently junked a '93 Aerostar that also had factory 4.10s...

Back before O/D trans were common, 3.25 or 3.50 RAR were the norm on the street(my '64 Galaxie 500 with 390 & three on the tree had 3.50s factory, as does my '69 428 Cobra Jet), even 4.11 & 4.30  without O/D was not uncommon... With a 4.10 & a lockup AOD O/D of .68, the final ratio is 2.79, Hell grandmas '60s/'70s LTD ran 2.75s and no one though of those as having too much gear...

Only possible down side to a deeper gear is you may need to have the drive shaft balanced, as it still spins at the ratio of the rear end...

I know nothing on gear ratios

Reply #29 –
I have a 88 xr7 that i race at the local track, i know from experience that a 4.10 is too much for a stock cars 3.55 is  about right in my opinion, My car gets up and goes from 0-60 takes no time to bury the speedo and the car cuts out at a certain rpm.