c4 vs. AOD

BurninBurt · 12-30-2000, 09:42 PM

I've got a lightly modified 91 GT with a stock AOD. But I've got a chance to get a c4. The question is...do I want the c4. What are the advantages and disadvantages of these two transmissions?

Five0 · 12-30-2000, 10:02 PM

From what I understand about these transmissions is that the c4 is stronger and lighter but you lose your overdrive, so your rpm's will be higher. The c4 is a good transmission but if you want to stay with a good aod lentech makes one rated to 600 hp for $1995.00. If you don't have that much money get the c4.

------------------
James Cox
nochevy@hotmail.com
1991 Mustang LX
Best 1/8 time on motor 7.686 @90.20mph

Paxtoned_88 · 12-31-2000, 12:01 AM

Quote:

Originally posted by BurninBurt:
I've got a lightly modified 91 GT with a stock AOD. But I've got a chance to get a c4. The question is...do I want the c4. What are the advantages and disadvantages of these two transmissions?

Like the earlier reply you received. Sure you will lose overdrive but you gain ability to shift the automatic c4 manually. Yes the c4 is stronger than the aod and is easier to work on to. If i remember correctly it is also lighter.

Regards,
Paxtoned_88

12-31-2000, 12:25 PM

Hey!! Wallace is right up the road from me. About the c-4, I sometimes wish I had gotten a c-4 instead of throwing all the money at the aod. Ok, you lose od but I've concluded the trade off is well worth it.

------------------
Rick
My 89lx(updated 11/5/2000)
My 97 Cobra

Fox Body · 01-01-2001, 03:33 AM

Hmmm. Kinda surprised with all the complements people are giving the C4. I got one and am very happy with it, but I always wondered how it would be to swap in a beefed up AOD (get that overdrive). Yeah, I have heard that it costs a lot to make an AOD strong compared to a C4, but does it really take much work? Am I right to say that if it weren't for the cost of beefing up an AOD, that most people would just about always prefer it over a C4?

-------------------------------
'79 Mustang Coup
4" Cowl
Weld wheels (15x6;15x8)
Stock 5.8L
C4 w/ shift kit
1.5" MAC full length headers
Holley 750 CFM
Edelbrock intake
2.5" Off road H-pipe
8.8" Rear end w/ 2.73:1 gears (sucks!)
Front: 225/60/15 Rear: 255/60/15 Eagle GT II
Sucky Purolator air filter that's choking my car.

Brian88 · 01-01-2001, 07:44 AM

I may go for the C4, since I do not drive real long distance. I am not worried about gas mileage because it is a mustang.

Rev · 01-01-2001, 02:05 PM

You can have it both ways. Gear Venders has an add on unit for the C-4 that's supposed to be super good. About $2000 though and a drive shaft job on top of that. These units are said to be good to 600 hp (you'd need a built C-4 to handle that). Lots of $$$, but they're supposed to be good. My $.02.

Rev

------------------
'66 Coupe, 306, 300 HP, C-4, 13.97 e.t., 100.3 mph
1/4 mi.

Five0 · 01-01-2001, 02:21 PM

Hey rev how about a little more info on what it is you are talking about.
What does it do and what is it?

------------------
James Cox
nochevy@hotmail.com
1991 Mustang LX
Best 1/8 time on motor 7.686 @90.20mph

Rev · 01-01-2001, 03:57 PM

It's an add on over drive unit that repaces the stock Tail shaft unit. It is longer than stock, so drive shaft work has to be done. I think there's a recent article in Mustangs and Fords on this. It does give either an automatic (tail shaft speed) or a manual push button operated over drive. It's supposed to be hellaciously strong (up to 600 lb/ft). They are expensive, $2000 or more. I bet they have a web site. Anyone know? Check Gear Venders.

Rev

------------------
'66 Coupe, 306, 300 HP, C-4, 13.97 e.t., 100.3 mph
1/4 mi.

Five0 · 01-01-2001, 04:23 PM

Thats pretty cool, I will have to check that out. Thanks rev

------------------
James Cox
nochevy@hotmail.com
1991 Mustang LX
Best 1/8 time on motor 7.686 @90.20mph

pro88 · 01-01-2001, 05:04 PM

C-4 all the way!!! The AOD is nothing but a boat anchor in my opinion. AOD's can't handle the power a C-4 can without dumping a small fortune into it.

BurninBurt · 01-01-2001, 05:42 PM

Thanks for all your info, BUT this is gonna be a daily driven car, not a pro street dragster! I'm not planning on dropping any other engine into my car anytime soon. So unless I go crazy with the mods then I'm not gonna need anything super strong. I was just wondering if the transmission ratio's were about the same, I thought they were but I'm not sure. And didnt the early fox-body mustangs come with c4's? On and I have read about gear vendors, I'd love to get them....If i happen to find a couple thousand lying around the house! Thanks for the help

89LXCarb · 01-01-2001, 07:37 PM

how much will your mileage suffer if you switch from an aod to a c4??
My car gets about 12 mpg now with an aod

------------------
4 cyl converted to 302
comp cams cam, ported GT 40 heads, Edelbrock intake, holley carb
Turbo coupe rear with 373's
4 inch cowl hood
finally done after what seemed like forever!!!!!

FivepointOH · 01-01-2001, 08:49 PM

Personally, i'm going with a lentech. They are good up to 700hp and have overdrive intact with or without lockup. My car is a daily driver and I hope to be making 450-500rwhp once I get it finished...
------------------
92 AOD GT, K&N, ram air, pulleys, 2 ch. flowmasters, 4:10's, shift kit, 1 5/8 mac longtubes and offroad hpipe 14.249 @ 97.34 mph before the headers and hpipe

[This message has been edited by FivepointOH (edited 01-01-2001).]

12-30-2000, 09:42 PM	#1
BurninBurt Registered Member Join Date: Dec 2000 Location: Wallace, NC, USA Posts: 24	c4 vs. AOD I've got a lightly modified 91 GT with a stock AOD. But I've got a chance to get a c4. The question is...do I want the c4. What are the advantages and disadvantages of these two transmissions?

12-30-2000, 10:02 PM	#2
Five0 Registered Member Join Date: Apr 2000 Location: middleburg, fl, usa Posts: 1,134	From what I understand about these transmissions is that the c4 is stronger and lighter but you lose your overdrive, so your rpm's will be higher. The c4 is a good transmission but if you want to stay with a good aod lentech makes one rated to 600 hp for $1995.00. If you don't have that much money get the c4. ------------------ James Cox nochevy@hotmail.com 1991 Mustang LX Best 1/8 time on motor 7.686 @90.20mph

12-31-2000, 12:25 PM	#4
rbatson Guest Posts: n/a	Hey!! Wallace is right up the road from me. About the c-4, I sometimes wish I had gotten a c-4 instead of throwing all the money at the aod. Ok, you lose od but I've concluded the trade off is well worth it. ------------------ Rick My 89lx(updated 11/5/2000) My 97 Cobra

01-01-2001, 03:33 AM	#5
Fox Body Mustang Maniac Join Date: Sep 2000 Location: GA, U.S.A Posts: 2,266	Hmmm. Kinda surprised with all the complements people are giving the C4. I got one and am very happy with it, but I always wondered how it would be to swap in a beefed up AOD (get that overdrive). Yeah, I have heard that it costs a lot to make an AOD strong compared to a C4, but does it really take much work? Am I right to say that if it weren't for the cost of beefing up an AOD, that most people would just about always prefer it over a C4? ------------------------------- '79 Mustang Coup 4" Cowl Weld wheels (15x6;15x8) Stock 5.8L C4 w/ shift kit 1.5" MAC full length headers Holley 750 CFM Edelbrock intake 2.5" Off road H-pipe 8.8" Rear end w/ 2.73:1 gears (sucks!) Front: 225/60/15 Rear: 255/60/15 Eagle GT II Sucky Purolator air filter that's choking my car.

01-01-2001, 07:44 AM	#6
Brian88 Registered Member Join Date: May 2000 Location: Maryland Posts: 110	I may go for the C4, since I do not drive real long distance. I am not worried about gas mileage because it is a mustang.

01-01-2001, 02:05 PM	#7
Rev Registered Member Join Date: Nov 1998 Location: Houston, Tx. Posts: 3,887	You can have it both ways. Gear Venders has an add on unit for the C-4 that's supposed to be super good. About $2000 though and a drive shaft job on top of that. These units are said to be good to 600 hp (you'd need a built C-4 to handle that). Lots of $$$, but they're supposed to be good. My $.02. Rev ------------------ '66 Coupe, 306, 300 HP, C-4, 13.97 e.t., 100.3 mph 1/4 mi.

01-01-2001, 02:21 PM	#8
Five0 Registered Member Join Date: Apr 2000 Location: middleburg, fl, usa Posts: 1,134	Hey rev how about a little more info on what it is you are talking about. What does it do and what is it? ------------------ James Cox nochevy@hotmail.com 1991 Mustang LX Best 1/8 time on motor 7.686 @90.20mph

01-01-2001, 03:57 PM	#9
Rev Registered Member Join Date: Nov 1998 Location: Houston, Tx. Posts: 3,887	It's an add on over drive unit that repaces the stock Tail shaft unit. It is longer than stock, so drive shaft work has to be done. I think there's a recent article in Mustangs and Fords on this. It does give either an automatic (tail shaft speed) or a manual push button operated over drive. It's supposed to be hellaciously strong (up to 600 lb/ft). They are expensive, $2000 or more. I bet they have a web site. Anyone know? Check Gear Venders. Rev ------------------ '66 Coupe, 306, 300 HP, C-4, 13.97 e.t., 100.3 mph 1/4 mi.

01-01-2001, 04:23 PM	#10
Five0 Registered Member Join Date: Apr 2000 Location: middleburg, fl, usa Posts: 1,134	Thats pretty cool, I will have to check that out. Thanks rev ------------------ James Cox nochevy@hotmail.com 1991 Mustang LX Best 1/8 time on motor 7.686 @90.20mph

01-01-2001, 05:04 PM	#11
pro88 Registered Member Join Date: Dec 2000 Location: roseburg, oregon Posts: 87	C-4 all the way!!! The AOD is nothing but a boat anchor in my opinion. AOD's can't handle the power a C-4 can without dumping a small fortune into it.

01-01-2001, 05:42 PM	#12
BurninBurt Registered Member Join Date: Dec 2000 Location: Wallace, NC, USA Posts: 24	Thanks for all your info, BUT this is gonna be a daily driven car, not a pro street dragster! I'm not planning on dropping any other engine into my car anytime soon. So unless I go crazy with the mods then I'm not gonna need anything super strong. I was just wondering if the transmission ratio's were about the same, I thought they were but I'm not sure. And didnt the early fox-body mustangs come with c4's? On and I have read about gear vendors, I'd love to get them....If i happen to find a couple thousand lying around the house! Thanks for the help

01-01-2001, 07:37 PM	#13
89LXCarb Registered Member Join Date: Jan 2000 Location: Columbus Grove, Ohio, USA Posts: 267	how much will your mileage suffer if you switch from an aod to a c4?? My car gets about 12 mpg now with an aod ------------------ 4 cyl converted to 302 comp cams cam, ported GT 40 heads, Edelbrock intake, holley carb Turbo coupe rear with 373's 4 inch cowl hood finally done after what seemed like forever!!!!!

01-01-2001, 08:49 PM	#14
FivepointOH Registered Member Join Date: Jan 1999 Location: Sugar Land, Tx USA Posts: 478	Personally, i'm going with a lentech. They are good up to 700hp and have overdrive intact with or without lockup. My car is a daily driver and I hope to be making 450-500rwhp once I get it finished... ------------------ 92 AOD GT, K&N, ram air, pulleys, 2 ch. flowmasters, 4:10's, shift kit, 1 5/8 mac longtubes and offroad hpipe 14.249 @ 97.34 mph before the headers and hpipe [This message has been edited by FivepointOH (edited 01-01-2001).]